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PART III

OUTSIDE MACHINIST TRAININGINSTALLATIONS, MAINTENANCE, REPAIRS

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PART III

Running a Tight Line

PURPOSE OF A TIGHT LINE

A tight line is used to locate the center line of the line shaft. The line shaft is connected to thepropeller at the stern and ends in the engine room, an over­all distance of about 70 feet. Thisline shaft, see Fig. 218, is made up of four lengths, coupled together to form one continuouslength and supported by bearings which are held securely on foundations placed at suitableintervals. The foundations for the bearings must be secured to the tank top of the doublebottom. See Ship Terms and Locations, Part I.

Fig. 218­­Line Shaft

STERN FRAME

The stern frame is a steel casting which has been welded to the stern plates of the hull, thusbecoming a solid part of the ship. See Fig. 219. The opening "a" is cast in the stern frame,and it is through this opening or "eye" that the line shaft turns and thus turns the propeller.

The eye must be bored out, and the center ofthe bored hole must be exactly in line with thecenter line of the keel and the correct heightabove the tank top, mentioned in the firstparagraph of this instruction sheet. Check onthis height with the leader.

POSITION OF LINE SHAFT

In the engine room, the center of the line maybe 3' 1­1/4" above the engine bed. This variesaccording to the type of ship.

Fig. 219­Stern Frame in Place

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Fig. 220 ­ Line Shaft Assembly

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The center of the line shaft may be 3'­8­1/4" above the thrust bearing foundation. This alsovaries. Enough stock has been left in the stern frame eye to allow for boring out. The enginefoundation has been installed in the correct relationship with the center line of the ship. Thereis a center line marked off on the bulkheads and deck plates of the ship. The stern frame hasbeen lined up with this center line and welded in place.

CENTER OF LINE SHAFT

All that now remains to be done is to establish a center line above the deck plates and in linewith the ship center line. This is the purpose of a tight line. From this tight line,measurements are taken to locate the spring bearing, the thrust bearing, the supports for thepropulsion motor, the circle for the holes in the three bulkheads (see note) aft of thepropulsion motor, the stuffing box and the line shaft in the engine­room watertight bulkhead,and the circle for the bored hole in the eye of the stern tube. See Fig. 220.

NOTE: Some ships have more or less than three bulkheads at this location,depending on the type of ship. The operation of boring, however, remains the same

Fig. 222­Target Stand Assembly

in principle.

TIGHT LINE

The tight line used on this job is a piano wire, .018 of an inch in diameter. The same size ofwire and the same tension are employed each time a "tight line" is run. On oil tankers, thelength of the line is about 70 feet from one end support to the other. On other types of shipsthis distance will vary. Figure 221 shows these two supports: A "horse" on the outer face ofthe "eye" and a "line target" at the other end of the line, in the engine room. See "a" and "d".

Fig. 221­­Target Stands Set to Center Line of the Ship

SETTING THE TARGET STANDS OR SUPPORTS

The target is a centering device, or metal bar, which is bolted across the two columns of anangle iron support that may be bolted or tack welded to the deck plates or tank top. See Fig.222. In order to

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set the target in the correct position, a chalk line is stretched from the engine room to theouter face of the eye at the stern, and by means of a plumb bob and line the chalk line islocated exactly above the center line of the ship. See Fig. 221.

NOTE: The center line of the ship was located by theshipfitters all along the tank top and on bulkheads withcenter punch marks as the ship was being built. The outsidemachinist follows all such center lines when laying out hiswork.

Figure 221 is a view looking down on the entire line shaftlocation as in the top view, Fig. 220. A "horse" 'a" is placedacross the stern­frame eye. A target stand (See Fig. 222) isset in position as at "d". The chalk line "g" is adjusted untilits position is directly over the ship center line which wascenter punched on the deck by the shipfitters. A plumb boband line are used to determine the correct position of thechalk line.

The distance from "a" to "d" is about 70 feet, and a targetstand is set up, as at "e", every ten feet. The chalk line givesthe location for the center of the target stand and the heightof the target stand crossbar. When all the targets have beenplaced, the crossbars are adjusted so that they just abouttouch the chalk line on the under side. When doing this, make sure the chalk line is stretchedTIGHTLY.

NOTE: All target stands are not of exactly the same construction, but they all servethe same purpose. When the tight line has been run and the necessary pointslocated from the line, the target stands are stored away for the next job. Alwaysstore the target stands carefully, together with all bolts, nuts, and crossbars, so thatno time may be lost in looking for this equipment the next time it is to be used.

PLACING THE TIGHT LINE

The chalk line is now removed entirely. It has served its purpose. The support "a" is relocatedfor holding the tight line. See Fig. 223. Two brackets, "k", are tack welded in placetemporarily. These brackets support two stools "l". "a" is now supported by the stools. Thestools and the bar are bolted to the brackets and may be adjusted to bring the tight line into

Fig. 224­­Tension Weight and Reel

alignment with the ship center line.

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Fig. 223­­Cross Bars Centered to Hold Tight Line

The reel and supporting bracket, "h", arebolted to the target crossbar in the engineroom. See Fig. 224. Check the reel to see thatit is well oiled and running free. Check thestop screws on the reel to make sure that thereel is locked in all positions before locatingany tram marks. The tight line is unwoundcarefully and carried back through the severalopenings in the engine­room bulkhead: thestern­tube bulkhead, the bulkheads betweenthe stern frame and the stern­tube bulkhead,and finally through the eye of the stern framewhere the end of the tight line is securelyfastened to the crossbar "a". Figure 224 showsthat the reel is notched in four or more places.The weight "j" is hung from one of thesenotches.

TENSION ADJUSTMENT

The piano wire used as a tight line is .018 ofan inch in diameter. When this size of wire issupported at two Fig. 224­­Tension Weight and Reel places, 70 feet apart, and stretched witha certain tension, the "sag" of the wire will form a long, gentle curve. This curve is alwaysthe same if the wire is supported, as above, and tightened the same amount each time.

A 27­3/4 pound weight is used to keep the wire in tension when the over­all distance is 70feet. See "j", Fig. 224. The amount of sag has been figured very carefully. It is definitelyknown that a tight line always sags a certain fixed amount, according to the size and length ofthe line. See illustration, Fig. 225.

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Fig. 225­­Showing the Sag in a Tight Line

SAG BLOCKS

Inasmuch as it is definitely known how much a tight line sags in ten feet, it is only necessaryto raise the wire that much to make the line level. Figure 225 gives the correct amount atevery ten feet. Figure 222 shows two small pins in the target or crossbar which is bolted tothe target stand. These pins are there to hold the sag blocks in place and to guide the tight linealong the center of the target stands. Figure 226 is an illustration of a sag block located inplace over the two pins in the crossbar. Sag blocks of the same thickness as mentioned inconnection with Fig. 225 are used as long as the distance between tight­line supports remains70 feet. If this distance changes, sag blocks of a different thickness must be used.

Fig. 226­Sag Block Pins

Fig. 227­­Tram Marks on Stern Frame Eye

ADJUSTING THE CROSSBAR

With the tight line in tension, the end supports are carefullyadjusted to bring the wire directly over the ship center lineas was done with the chalk line. This adjustment must beexact. A plumb bob and line are used as before. The heightof the tight line at the engine­room­target end must beaccording to the blueprint. This height is usually 5' 2" fromthe engine room tank top to the under side of the tight line.Check and recheck the height of the line to provide for achock thickness of 1­1/2" under all of the bases of the unitsbeing installed. Check with the leader.

The crossbars must now be raised and adjusted until a light shows the bar barely touching thewire. Tighten the crossbar bolts and check with the leader. When all the crossbars have beenadjusted, place the sag blocks on the pins and recheck at every point to make sure theadjustment is correct for height and center location. Remember the tight line is the center ofthe line shaft. Measure carefully, tighten all adjusting bolts, and check with the leader.

LOCATING MACHINING POINTS

Before any machining, such as boring and facing, can be permitted, the tight line must beremoved. Certain measurements have to be taken from the tight line, and markings made.Figure 227 shows the outer

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face of the stern­frame eye. The center of thetight line is plainly marked. Four center punchmarks must be made as shown at points "c".

The distance of the center punch marks from thecenter of the tight line should be about one­halfinch greater than the radius of the bore in thestern­frame eye. The reason for this is that afterthe eye is bored a check may be made from these"register" or tram marks and the accuracy of thework thus assured. A cold chisel is used to marka small square around the tram marks so thatthey may be easily located.

Similar measurements and center punch marksare made at every opening through which theline shaft will pass. It should be quite clear that ifthe tight line is run correctly and if the trammarks are located accurately, the finished job will be satisfactory. The slightest error meansserious trouble later.

When taking a measurement from a tight line to a tram mark, "snap" the line to make sure itis on center. Unless this is done there is danger that the line may be slightly to one side.Check this repeatedly.

NOTE CAREFULLY:

When measuring from a tight line with the tight line itself as a center to a point 10"from that center, be sure to subtract half the diameter of the tight line from the 10".

The diameter of the tight line is .018".The radius of the circle is 10".The measurement from the side of the tight line to one edge of the diameter of thecircle would be 10­.009, or 9.991 inches.

For any measurements from a tight line set the micrometers to allow for half the diameter ofthe tight line.

QUESTIONS

1. How much does a tight line 70 feet long and .018" in diameter sag in the center if

unsupported?

2. If the tight line is not located directly over the ship center line, how will this affect thealignment of the line shaft?

3. State the precaution which should be taken when locating tram marks with a center punch.

4. How does the mechanic make certain that the tight line is "on center" when takingmeasurements?

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5. What device is used to hold the tight line at the proper tension?

6. What is the correct distance from one target support to the next?

7. Why is a chalk line run before setting the target supports?

8. Explain the reason for burning a hole larger than the stern tube in some bulkheads.

9. How does the diameter of the tight line affect a measurement taken from the center of thetight line to the circumference of any circle scribed about the tight line as the center?

* Removing A Tight Line

INFORMATION

The piano wire used for locating the shaft center line is comparatively expensive, and theslightest abuse can render it useless for further service. The time required to prepare anotherline would have to be added to its cost in case a second tight line had to be used. If a tightline is kinked, it is of no further use as a tight line.

MATERIALS

Tight line ready for removal

PROCEDURE

1. Unfasten the after end of the tight line from the adjustable bracket.

2. Have one helper hold loose end of line and carry it toward the reel which winds up the lineat the other end.

3. Have a second helper apply oil to the line with a rag.

4. Turn the reel crank, and wind the line on the reel neatly until all the wire is wound.

5. Secure the loose end by inserting it under two or three strands of line and then pulling it uptight.

6. Wrap an oiled rag around the line on the reel and place the reel of line in the reel box.

7. When you have finished with the line and the reel, see that they are returned to the toolroom.

QUESTIONS

1. Why must care be used in removing the tight line from the shaft center line location?

2. Three men are used in removing the line. What does each man do?

3. What precaution is taken before placing the reel of line in the box?

* Adapted from "Outside Machinist", Alabama State Department of Education.

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Setting A Portable Boring Bar

Fig. 228­­Stern Frame

INFORMATION

The illustration at the right, Fig. 228, shows a heavy steel casting, the stern frame, which iswelded solid with the stern plates of a ship's hull. The hole in the hub is the stern­tubehousing and is called the "eye" by shipyard mechanics.

The lower portion "a" is called the SKFG. The surface"b" is called the outer face of the eye and "c" is called theinner face of the eye. The stern­tube housing must bebored out to a certain size to fit the stern tube. Seeappendix for definition of stern tube.

Figure 220 shows a longitudinal cross section of a ship'shull in the bottom view. Note carefully the locations ofthe bulkheads, bearings, stools, and couplings. The stoolswhich support the shaft bearings are welded to the tanktop before the tight line has been run. When theconstruction is complete, the center line of the line shaftmust occupy the same position as the tight line occupiedbefore it was removed.

While the tight line was in position, tram marks were accurately located on the outer face ofthe eye (Fig. 227) and around the rough hole in the stern­tube bulkhead (Fib. 220). Trammarks were located on the engine­room watertight bulkhead and on the two bulkheadsimmediately forward of the stern frame.

The diameter of the portable boring bar is 5" to 14". A heavy bar is always used on largework. Always use as heavy a bar as possible to avoid spring. See Fig. 229. The diameter ofthe eye will easily accommodate the boring bar. Other holes in the bulkheads have beenburned out small enough for finish­machining and at the right location with the center line.

The eye in the stern frame is to be bored 30".

The hole in the first bulkhead forward of the eye is to be bored 31".

The hole in the second bulkhead forward of the eye is to be burned out 32­3/4" to allow thestern tube to pass freely, but it is not bored. If there are other bulkheads at this location, theblueprint will show which ones are to be bored and which are to be burned.

The hole in the engine­room bulkhead is bored 32­3/4" less about .003 of one inch. The .003of an inch is to allow for a press fit when pulling in the stern tube.

Study Fig. 229 carefully. The fittings on the main boring bar may all be removed, leaving abare bar. The entire assembly may be moved backward or forward and secured in any desiredlocation.

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Fig. 229­­A Portable Boring Bar Assembly

Four stools, Fig. 229, swivel on the yokes and have several bolt holes to allow the yokes tobe secured to a support as conditions require.

The yoke on the end opposite to the hand­feed wheel may be removed and the bar slippedinto the after end through the hole in the stern­frame eye if the ship has twin propellers. Otherparts of the portable boring bar have to be removed while preparing to set the bar in a tightplace where one propeller is used. In this case it is lowered into the after peak and runthrough the eye from the inside.

The boring bar is slung in a chain fall and passed through the eye where a second chain fall isready to receive it. The bar is located by raising or lowering the chain fall; it is bracedsidewise as near to the center of the layout as possible by rough measuring. The yokes areadjusted to a convenient position, and supports to which the boring­bar yokes may besecurely bolted are welded to the deck plates and bulkhead. See Fig. 230. These supports aresometimes called "spiders".

After the boring bar is secured to the spiders it may be adjusted to a location exactly centralwith the tram marks which were located from the tight line.

As the main bar of the boring bar assembly is straight and true, any measurements that maybe taken from the outside diameter of the bar will

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Fig. 230­­Boring Bar Supports, Inside and Outside

be just as accurate as if taken from the actual center of the bar. Fig. 233 shows the boring barbody lined up in the center of the four tram marks which were put on the outside face of theeye while the tight line was still in place. Hermaphrodites may be used to check the distanceall around the boring bar until it is exactly in the center. The same procedure is followed atthe other end of the bar where it projects through the stern­tube bulkhead. After the bar hasbeen securely bolted in position, the job is checked again to make sure of the alignment.

Figure 232 shows one of the bulkheads with a hole burned through. The four tram marks aremeasured from the tight line, and the boring bar is lined up with these tram marks.Measurements are taken from the tram marks as shown in Fig. 233, to the side of the boringbar as indicated by the reversed arrows. ­­­­> DISTANCE X <­­­­­ The distance "x" betweenthe arrow points is the same all around the boring bar. This measuring must be done verycarefully.

Figure 231 shows a boring bar set vertically. The men are boring the top gudgeon on thestern post. Note the strong backs at the upper and lower sides of the gudgeon. Thestrongbacks are secured to the vertical channels welded to the rounding surface of thegudgeon.

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Figure 230 shows a support welded to the "skeg" of the stern frame and bolted to thereduction­gear housing. This is done to hold the boring­bar assembly perfectly rigid while theboring is being done.

The job of setting up a portable boring barmay be summed up as follows:

PROCEDURE (Applicable in most cases)

1. Clear away all obstructions, tools, andloose materials which might interfere withthe handling of the boring bar.

2. Locate chain falls and planking atconvenient points for quick and safehandling of the boring bar.

3. Strip the boring bar of the yokes, toolholder, reduction­gear drive, air motor, andhand­feed.

4. Lower the boring bar into the engineroom. Wrap with bagging to prevent injuryto the finished surface of the bar.

Fig. 231­­Portable Boring Bar Set Vertical

for Boring Rudder Gudgeon

Fig. 232

5. Secure the boring bar in the chain fallpreviously located in the after peak, andbalance the bar so that it may be swungforward. Planking is placed to help slidethe bar out through the eye in the sternframe. Protect the bar with bagging, ifnecessary.

6. Support the outer end of the boring barwith planking and chain fall.

7. Reassemble the yokes and otheraccessories, and get ready to raise the barinto boring position.

8. Estimate where additional spiders andsupports should be secured to supportboring bar.

9. Have flat or angle supports cut, andwelded into position.

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10. Bolt boring­bar spiders to supports, and line up the boring bar.

NOTE: Measure from outside diameter of boring­barmain body to the tram marks previously Placed on thestern­frame eye and bulkheads. Use a steel scale andhermaphrodites. Keep the hermaphrodite scribing legto a sharp point. Re careful to hold the tool at rightangles to the center line of the boring bar. Themeasurements must be perfect if the stern tube is to bein correct alignment. Check with the leader.

11. install the tool holder, adjust the air motor,connect the air lines, and recheck all fastenings tomake sure the bar will remain in correct alignment.The boring bar should now be ready for boring the eyein the stern frame.

QUESTIONS

1. A heavy boring bar should always be used wherethere is sufficient room to set it up. Why is a heavy boring bar more desirable than a lightone?

2. What is the principal problem involved in setting a portable boring bar?

3. At what points are measurements taken to bring the boring bar central with the diameter tobe bored?

4. Explain the reason for removing the fittingsfrom the boring bar before setting through thestern­frame eye.

5. Point out the principal precautions to be takenwhen getting ready to set the boring bar throughthe stern­frame eye.

Fig. 233

6. What is the purpose of the swivels and yokes oneach end of a boring bar?

7. Explain the usual method of providing suitableplaces to which parts of the boring bar may be

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bolted to hold the boring bar in position while the boring job is being done.

8. State at how many points supports for the boring bar are welded temporarily; explain thepurpose of each support.

9. What would be the probable result if a boring bar slipped a little during the boringoperation?

10. What is the correct procedure after the boring bar appears to be set central with the eyediameter?

Boring A Stern Frame

ACCURACY OF A BORING JOB

There must be no errors in the boring of a stern frame. The stern frame casting is "welded in"with the hull plates of the ship, after which operation all the pieces become one unit. To ruina stern frame means a loss of time and materials that is difficult to estimate. Boring a sternframe is a man­sized job which the mechanic must approach with the fixed idea that everymove must be carefully and thoroughly planned. Mistakes are absolutely barred.

THE BORING JOB

Full instructions have been given for running a tight line. Full instructions have been givenfor setting a portable boring bar. The instructions given here are to be followed after theboring bar is in place, ready to bore the stern­frame eye and the bulkheads, which wereshown in Fig. 220.

Fig. 234­­Portable Poring Par Set Horizontal for Boring a Stern Frame Eye

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PROCEDURE

1. Adjust the tool holder and tool bit to the correct location. Turn the bar slowly to find wherethe high spots are on the inside of the eye. See Fig. 234.

2. Feed the tool into the full depth of the eye to make sure that there is plenty of clearanceand that there are no high spots to foul the tool and throw the "set­up" out of line.

3. When everything seems to be clear, check with the leader.

4. Set the tool to take a 3/16" cut, and feed slowly to get the "feel" of the tool. A faster feedmay be used if it is evident that the tool will "hold up" and that there is no "spring" in the "setup." (A cutting speed of 30 to 60 feet per minute is safe in most cases. Check with the leaderon this point.)

5. Continue to take roughing cuts until the inside diameter of the eye "cleans up".

6. Check with the leader at this point. Check all spiders, yokes, and stools frequently to makesure there is nothing slipping.

NOTE: As soon as the hole is cleaned up, a check can be made withhermaphrodites from the circumference of the bore to the tram marks. This servesas a double check on the accuracy of the work.

Fig. 235­­Checking the Diameter of a

Stern Frame Bore

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7. If the work is approved up to this point, continue boring the diameter until within 1/8" ofthe correct diameter.

8. Bore the bulkheads up to this point as outlined above.

NOTE: At this point the stern tube should be brought out to the job and carefullymeasured. As the diameter of the bore in the eye must be slightly smaller than thestern tube diameter, a very close measurement must be taken.

A very slight change in temperature affects metal in that all metals are sensitive toheat and cold. A stern tube that measured 30" in diameter in a warm machine shopwould very likely measure .005 less when taken to the ship ways to be installed.

The cold air in the winter months would shrink the metal, and it would be toosmall for the bored hole in the stern frame unless the measurements were takenwhen both stern frame and stern tube were the same temperature. This is the reasonfor bringing the stern tube to the ship ways to be measured before the finish cut istaken in the bore.

When measuring the stern tube to get the size and the diameter to bore, proceed asfollows:

Fig. 236

(a) With a pair of outside calipers, carefully measure the diameter of the stern tube.

(b) Lay the outside calipers on a level surface and set inside micrometers to thepoints of the calipers.

NOTE:

Special inside micrometers are used for this job. Thereis an offset in the micrometer which will clear theboring bar. See Figs. 235 and 236.

MEASURING THE INSIDE DIAMETER OF THESTERN­FRAME EYE.

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(c) When the setting has been accurately determined, reduce the size .008 to allow for a pressfit. This must be done very carefully.

(d) Now proceed with the finish cut for about 1/8" and check with the micrometer. If the sizeis correct, proceed. If too large, back off and try again. DO NOT CUT IN LENGTHWISEFOR MORE THAN 1/8" BEFORE TRYING FOR SIZE. See Fig. 235.

Fig. 237­­Finish Cut in a Stern Frame

(e) When the bore checks correctly with the mikes, proceed with the finish cut. Watch thetool carefully as the boring proceeds. If the tool begins to burn, STOP. Check with the leaderif in doubt as to how to proceed. See Fig. 237.

If the finished hole is bored tapering, the stern tube will likely seize when being "pulled in";so every precaution must be used to have a straight hole.

NOTE: When finished with boring, do not move the boring bar until the diameter of the holehas been checked and approved by the leader or inspector.

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QUESTIONS

1. When adjusting the tool holder to begin taking a cut, what precaution should be taken toprevent the tool's "fouling" the work?

2. How heavy should the tool be set in for the first cut in a stern­frame eye?

3. At what speed is it considered safe to start a roughing cut?

4. What is understood by the phrase "clean up the inside diameter" of a boring job?

5. Explain the usual causes for the boring bar's getting out of line during a boring operation.

6. How is the rough bore checked for accuracy with the center location before proceedingwith the job?

7. How much stock is left for a finish cut in a rough­bored "eye"?

8. State the usual allowance for a press fit between the "eye" and the stern­tube diameter.

9. Explain how the measurement is taken for the finished diameter of the bore in the "eye".

"Pulling in" A Stern Tube

PURPOSE OF A STERN TUBE

The stern tube is the shell for the lignum vitae, tail­shaft bearing. The stern tube varies from8 to 20 feet in length. The outside diameter is stepped, that is, the end that fits in the stern­frame eye is smaller than the end that fits in the stern­tube bulkhead.

CORRECT FIT FOR A STERN TUBE

When the stern­frame eye and the stern­tube bulkhead are bored to the finished size, the sterntube should "pull in" under pressure, because the stern tube is turned .008 of an inch largerthan the stern­frame eye at the stern end (see point "a" Fig. 238), and .003 larger than thestern­tube bulkhead at the bulkhead end (See point "b", Fig. 239). Figure 239 illustrates atube partially pulled into place.

USING THE CHAIN FALLS

When the bored holes in the stern­frame eye, stern­frame bulkhead, and the interveningbulkheads have been brought to size to allow for a pressed fit as outlined in the lastparagraph, the' stern tube is lowered into the engine room. Chain falls are placed in positionto take the stern tube off of the crane. Sometimes as many as 8 or 10 chain falls are used tocarry the stern tube as it is worked back to its place from one chain fall to another. The sterntube must be protected with bagging to prevent scoring the finished surface while the tube isbeing handled by the chain falls.

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Fig. 240

Fig. 238­­Stern Tube in Place

PREPARING TO "PULL IN" THE STERN TUBE

Figure 239 shows the stern tube partly drawn in through the stern­frame eye and the stern­tube bulkhead at "a" and "b". A heavy bolt is shown at "c". The bolt extends from the outsideof the bulkhead end of the stern tube, through a strong back "d", and all the way through thestern tube and the strong back "e". A hydraulic ram "f" is secured to the outside of the strongback "e". The ram draws the stern tube into place.

Two cradles, Fig. 240, are used under the pull bolt to keep it exactly central in the stern­tubebore. The cradles and made an easy fit for the stern­tube bore and the pull bolt. One cradle isplaced at the stern­frame end, and the other is placed at the stern­tube, bulkhead end. See "x"and "y", Fig. 239.

"PULLING IN" THE STERN TUBE

The hydraulic ram works against the washer and nut at "g" and has an effective draw of about10 inches. When the ram has reached the 10" limit, another washer (10") "h" is placedbetween the strongback and the first washer under "g" and another 10" section of tube isdrawn in. This is repeated until the stern tube is completely drawn into place, making ametal­to­metal joint at the stern­tube shoulder and forward end of eye. See Fig. 238.

Fig. 239­­"Pulling In" a Stern Tube

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A pressure of not less than 3500 pounds registered on the gauge isstandard for a correct fit. This pressure may run as high as 6000pounds, but it must not be less than 3500 pounds. A pressure gaugeis connected to a hydraulic pump which acts on the ram. The gaugeshould be watched constantly for variations which will indicate toomuch or too little pressure.

The lock nut, Fig. 241, has in the circumference, several machinednotches into which the spanner wrench fits when the nut is beinginstalled or removed. When the lock nut has finally been "snugged home", a hole is drilled inthe face of the stern­frame eye and tapped out for a lock stud. The location of this hole bringsthe lock stud at the bottom of one of the notches. After the lock stud has been secured inplace, tack weld it fast. See "a" Fig. 241.

When the stern tube comes to the job, it is packed withsawdust to keep the lignum vitae bearing blocks fromdrying out and cracking. Never remove the sawdust untilready to null the stern tube into place. While the operationof pulling in a stern tube is proceeding, the job isinspected and criticized by the American Bureau ofInsurance, or the Lloyd Insurance Company, and the agentof the shipowner. This is done to make certain that the jobwill conform to all underwriter requirements.

Fig. 241­­Lock Nut

The operation of pulling in a stern tube may be summedup as follows:

TOOLS ANDEQUIPMENT

1. Hydraulic pump2. Hydraulic ram3. Strongback assemblies4. Pull bolt5. Saddles for pull bolt6. Washers for pull bolt7. Stern­tube nut wrench8. Drill for lock stud9. Air drill10. 30­pound sledge11. Chain falls12. Melting ladle13. Pouring ladle14. Heating torch

MATERIAL

Planking for skids andplatformWhite lead and oilLock studTight metal

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Fig. 242­­Inspecting the Progress of the Stern Tube Through the Eye

Fig. 243

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PROCEDURE

1. Lower the stern tube into the engine room.

2. Receive the stern tube in one or more chain falls, and swing to the next chain fall, passingthe tube aft.

3. Enter the tube in the bulkhead hole, and pass it through to the stern­frame eye.

4. Apply white lead and oil to the tube, bulkhead, and eye surfaces.

5. Install the pull bolt, and adjust strongbacks and hydraulic ram.

6. Pump pressure until the pull bolt takes hold.

7. Now examine all equipment and fastenings to make certain the tube is entering "fair".

8. Pull the tube in as outlined in the text of this instruction sheet.

9. When the tube is in place, check with the inspector for his approval.

10. If approved, remove strongbacks, hydraulic ram, and pull­bolt; clear the platform forinstalling the lock nut.

11. Drill through the stern­tube flange for studs, and tap holes to suit.

12. Install studs with grommets and nuts on the after side of stern­tube bulkhead. See Part II,Making a Watertight Joint, Fig. 145 for application of stud and grommet.

13. Place a metal band around the flange of the stern tube in readiness for pouring tightmetal.

14. Build up a clay mud seal all around the ring to prevent the tight metal's escaping when itis poured into the joint.

15. Build up (on top of the metal band) a clay mud cup into which the tight metal may bepoured.

NOTE: While the metal band is being placed and the mud seal is being installed,the tight metal should be made ready. The tight metal is melted in a ladle over aheating torch. The metal is considered to be hot enough to pour if a pine stick takesfire when inserted in the melting metal. This test indicates approximately atemperature of 535° to 550° F.

16. Pour the tight metal into the cup previously prepared. Pour fairly fast to insure a goodjoint and avoid air pockets.

NOTE: In cold weather the bulkhead and the stern­tube flange should be preheatedto prevent chilling the metal as it is poured.

17. Remove the band and calk the tight metal with a rough calking tool. This procedure willtighten up the joint and make certain there are no gas or air pockets.

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NOTE: In the event that a gas pocket or an air pocket is discovered, the metal mayhave to be melted out and repoured. This is almost sure to be necessary if thepocket is found on the bottom side of the joint.

18. Install washers and nuts on the studs, and draw up tight. See Fig. 243.

19. Fill up the after peak with water from a shore­line hose to make the necessary test forleakage around the joints between the stern­tube flange and bulkhead and the stern tube andstern­frame eye.

QUESTIONS

1. Why is a forced fit necessary between a stern­tube diameter and the stern­frame eye?

2. How much difference in diameter should there be between the bore in the stern­frame eyeand the after end of the stern tube?

3. Explain how a stern tube is carried back into position after 'it is lowered into the hull.

4. What protection should be given a stern tube during the operation mentioned in step 3?

5. What is the purpose of the two cradles which are placed under the pull bolt in the sterntube?

6. State the reason for pulling in the stern tube with a pressure of 3500 lbs. registering on thegauge.

7. When is the sawdust removed from the inside of the stern tube? Why is it not removedsooner?

8. When is the stern­tube job inspected and by whom?

9. What is meant by the word "fair"?

10. Why is a small space left between the stern­tube bulkhead and the stern­tube forwardflange? ("c" Fig. 238)

11. Explain in as few words as possible how and why tight metal is poured at the forward endof the stern tube.

12. How are the stern­tube joints tested for leakage after the installation is complete?

Installing A Propulsion Motor

PROPULSION MOTOR DRIVE

The propulsion motor is keyed to one end of the line shaft, and the propeller is keyed to theother. When the propulsion motor turns, the propeller turns at the same speed and so movesthe ship through the water. The propulsion motor (See Fig. 244) is electrically operated, verymuch like any other electric motor except that it is installed on the forward end of the lineshaft; the line shaft thus becomes the axle upon which the rotor turns. The foundation isinstalled according to the location given on the blueprint. Figure 244 shows the motor

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housing and the line shaft housing. The motor is inside the large housing. Note handleswhich are used to grasp the housing sections when opening or closing the housing assembly.

Unless the installation of the propulsion motor iscorrect in the smallest detail it will not be passedby the inspector. The propulsion motor islowered into the ship by ship riggers, set hack asfar off on the foundation as possible to giveclearance for installing the rotor, and after therotor is installed the entire stator unit is shifted tothe correct position on the foundation.

PRECAUTION

Every precaution should be taken when installingthe stator to make sure that there is no damagecaused to either the rotor or the stator. It isadvisable to place shims around the inside of thestator to serve as guides when sliding the rotorinto place.

Fig. 244­Propulsion Motor and Line Shaft

INSTALLING THE MOTOR

At the time the final installation is made, the lineshaft has already been installed. See Fig. 220.The propulsion motor must be set directly withthe line shaft for the line shaft cannot be moved.This calls for extremely careful measuring. Therotor shaft is set in line with the line shaft. As thepropulsion motor weighs sixteen tons or more,the entire job must be done carefully.

When the motor is set in position and approvedby the inspector or the leader, the job of fittingchocks is begun. When the chocks are fitted, thecorners are drilled and reamed for fitted bolts;the bolts are installed and drawn down tightly;and then the rotor shaft is revolved and"indicated" to make sure it is in perfectalignment with the line shaft.

A piece of insulation approximately .125" thickis placed between the top side of the chock andthe pedestals of the propulsion motor on theforward bearing. After the chocks are fitted andare found to be satisfactory, they are removedand an amount equal to the thickness of

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the insulation is machined off of the top of each chock. This job must be done very carefullyor the alignment of the other chocks will be thrown off.

The fitted bolts through the forward bearing are insulated at the point where the bolts passthrough the pedestal and the upper side of the chock. These points are insulated to prevent aground on the forward bearing. See Fig. 245 and 246.

If an arcing condition should be set up, the shaft and the babbit bearing in the propulsionmotor would be scored and both would have to be replaced. Such an arcing condition mustbe made impossible by proper insulation.

TOOLS

1. Drills of the correct size2. Corner drilling machine3. Reamers for couplings (taper and straight)4. Reamers for hold­down bolts5. Open wrench set6. Scrapers7. 6" scale8. Thickness gauge (.002"­.060")9. 24" inside calipers Or Special telescopic gauge

MATERIALS

Shim stock

10. Taper gauge (0"­.390")11. Center punch12. Machinist's hammer13. 10­lb. maul14. 20­1b. maul15. Necessary taps16. Jacking screws17. Diesel side jacks

GENERAL PROCEDURE

1. Find the correct location of the rotor unit onthe foundation from the blueprint. Level theunit on chocks or wedges, or both, preparatoryto bolting down.

2. Align the couplings on the rotor shaft and theline shaft.

Fig. 245­­Line Shaft Bearing and Pedestal

3. Check with the leader.

4. Fit chocks as previously instructed (See PartI) under the bearing pedestal of the rotor.

5. When the chocks are correctly fitted, checkwith the leader.

6. If the work up to this point is approved,proceed to drill and ream the corner holes forfitted bolts.

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Fig. 246­­Typical Insulated Stud Installation

7. Install fitted bolts and draw the nuts down tightly. Be sure to install the insulated boltscorrectly.

8. Check the alignment of the rotor shaft with the line shaft to make sure there has been noerror.

9. Using jacks or wedges, line the stator up with the rotor and check the spacing between therotor and the stator with a 12" tapered wedge gauge. See Fig. 247.

NOTE: The propulsion motor is set "up and down" to align with the line shaft .005of an inch above the center. This is to allow for wear as the motor "settles" in thebearings. The fore­and­aft location is found on the blueprint.

10. When the rotor and stator appear to be in perfect alignment all around, check with theleader. If the alignment is correct, fit the chocks under the stator base.

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Fig. 247­­The Stator is Jacked Up True With the Rotor

11. Drill, ream, and install fitted bolts on the four corners. Pull the nuts up tightly. Use everyprecaution to insure the nuts being pulled up to the limit.

Fig. 248­­Typical Turbo­­Generator Unit

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12. Re­check the spacing between the rotor and the stator.

13. Call the leader, and have the job inspected up to this point. Figure 248 shows a turbo­generator and exciter set. Several of these units are installed in the engine room or adjacent tothe engine room, and they generate power which is used to drive the propulsion motor andnumerous other electric motors throughout the ship. The ship lighting system also drawscurrent from the turbo­generators.

QUESTIONS

1. When a propulsion motor is being installed, why is the rotor aligned before the stator?

2. Explain the procedure of aligning the stator with the rotor.

3. How often is the spacing checked between the rotor and the stator?

4. Why is the stator aligned with the rotor in such a way that the center line of the rotor is.005 of an inch above the center of the stator?

5. Describe a diesel side jack.

Installing Fan And Motor For Air Cooler

FAN REDUCES TEMPERATURE

The temperature in the vicinity of the propulsion motor normally varies from 150 to 180

degrees Fahrenheit. As the propulsion motor is installed in the engine room, it is subject tohigh temperatures caused by heat radiated from the steam lines and absorbed by thesurrounding atmosphere. in winter these temperatures are reduced somewhat by coolerweather; but in summer, and in southern climates especially, the temperature around thepropulsion motor must be reduced or the motor will run so hot that it may burn the bearings.

An air cooler is installed in a convenient place; a fan and motor are connected to the aircooler by a "circulating duct"; and the air around the motor is drawn through the air coolercontinuously, bringing the temperature down to about 115° Fahrenheit. See Fig. 249.

CORRECT INSTALLATION

The importance of correct installation of the air­cooler fan cannot be stressed too much.When the ship is in service, there is an extremely heavy load on the propulsion motor. If forany reason the fan and motor should stop working, the temperature would likely go so highthat the motor windings would be in danger of burning out. If this should happen while theship is at sea, the results may be easily imagined.

FAN AND MOTOR UNIT

The fan­and­motor units are usually mounted on a base as one unit. Sometimes the fan­and­motor units come separate. In either case the work involved in making the installation ismuch the same.

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Fig. 249­­Westinghouse Air Cooler Unit

Figure 249 shows two pipe lines through which sea water is circulated for the purpose ofcooling the air that is blown through the air­cooler unit installed above the propulsion motorhousing. The air duct from the fan to the cooler unit is at the left. The fan and motor (notshown in the photograph) are mounted below and close to the propulsion­motor housing.

The shipfitters build the foundations; and when the unit is ready for installation, the shipriggers place it. The location on the foundation is laid out from the blueprint by the outsidemachinist. The fan may be anywhere from 38" to 52" in outside diameter. The revolutionsper minute may be about 1175 for large motors and about 1400 for small motors. The smallerfans operate at higher speeds. The foundation is installed on the engine­room tank top just aftof the main condenser.

Figure 250 shows a General Electric fan and motor. The motor is indicated at "a", the blowerat "b", the intake duct at "c", and the discharge duct at "d".

Figure 251 is a photograph of a General Electric Air Cooler. The blower discharge (hot air) isshown at "a"; the cooler tank (to reduce temperature) is indicated at "b".

PROCEDURE

1. From the blueprint, locate the correct position of the unit on the foundation.

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Fig. 250­­General Electric Motor and Fan

2. Level the unit on wedges preparatory to bolting down.

3. Drill the corner holes for fitting bolts through the foundation.

NOTE: Usually the unit is bolted down on metal chocks, but sometimes a woodcushion of suitable thickness is used to reduce vibration. (In this case metal chocksare not used.)

4. Fit corner chocks; drill, ream, and install fitted bolts; and draw down.

5. Fit the remainder of the chocks.

6. Have an inspector check the job for accuracy.

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Fig. 251­­General Electric Discharge Duct and Cooler Tank

Installing A Steam Boiler

DESCRIPTION OF A STEAM BOILER

Tankers and certain types of cargo ships are usually equipped with the boiler which isdescribed here. The boiler is built in the shipyard by the boiler­makers. When completelyfinished, the boiler is set on the ship by the riggers and bolted down by the outsidemachinists.

The boiler is known as a Babcock and Wilcox, oil­fired, tubular­header type. This unitweighs approximately forty­six tons when completed. Fig. 252.

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Fig. 252­­Babcock and Wilcox Oil Fired boiler

THE FOUNDATION

A foundation is constructed in the boiler room. The boiler room in a tanker is located in theafter end. The boiler room in a cargo ship is located amidships. The shipfitters build thefoundation, which is of heavy construction. It is finished off with two steel channels that

support the boiler, back and front. The foundation seat is a channel about 14" wide and 18"high. See Fig. 253.

The channel is welded securely to the foundation plate, and the boiler is bolted down to thechannels. The channels are called "stools".

Six 1­1/4" bolts are placed through each of the four bottom corners of the boiler frame andthe foundation stools.

LAYING OUT THE BOLT HOLES IN THE STOOLS

The locations of the bolt holes in the stools are taken from the blueprint. Before laying outthe holes in the stools, however, boiler­makers check the base of­the boiler to make sure theholes in the base match with the hole locations on the blueprint. If there is any discrepancy,the layout is corrected to agree with the boiler base. Figure 254 is a ton view of a foundationstool on the port side of the ship. A similar foundation is on the starboard side right next tothe port foundation. Two boilers are installed with about 3 feet between the adjacent walls.

When the machinist lays out the boiler locations, he takes all measurements from the shipcenter line, the boiler center line, and the foundation center line.

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Fig. 253­­Boiler Foundation Setting

SETTING THE BOILER

The boiler is picked up by the shipriggers and set on the foundation under the supervision ofthe outside boiler­maker leader. This is not done until after the holes are drilled in thefoundation stools­ A layer of seal tight cement about 1/8" thick is spread on the surface of thefoundation stools with a trowel. When the boiler is set on the stools, the cement forms acushion for the boiler and seals any uneven places on the surface. The cement hardensquickly, and thus a solid, durable joint is formed between the foundation and the boiler base.

Figure 252 shows various valves, gauges, and controls which are installed by mechanicsespecially trained for this purpose.

PRECAUTIONS

Certain precautions must be observed when installing any of the gauges, valves, and otherparts mentioned above.

(a) Examine the fittings closely to find if right­hand or left­hand threads are cut on theconnections.

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(b) Be very careful in handling brass fittings not to damage the fine threads.

(c) Use a wrench of the correct size on all fittings, and see that the wrench fits closely. (Somewrenches may be "sprung" although they are stamped the correct size.)

(c) Follow the directions given by the manufacturer or the ship­building company'sblueprints.

Fig. 254­­Plan View of Steam Boiler Foundation

Many of these accessories appear to be simple in form and do not seem to require any specialknowledge to install. This is far from true. Each particular piece of equipment requirescorrect handling and careful treatment.

As an example of the importance of working carefully and correctly, consider the work ofinstalling a Bailey feed­water regulator. The purpose of the regulator is to control the amountof water fed to the boiler so that it will not run dry and cause burning of the tubes. Theregulator also prevents an excess of feed water which causes "wet" steam and damagesturbine fins or cracks a cylinder head.

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* Bailey Feed Water Regulator InstructionsPrincipal of Operation ­­ See Fig. 255

The Bailey Thermo­Hydraulic Feed Water Regulator depends for its operation upon the factthat the volume of a given weight of low pressure steam is far greater than the volume of thewater from which that steam was made. The water which operates the regulator is sealed in aclosed system formed by the annular space between the inner and outer generator tubes, theconnecting copper tubing, and the metal bellows of the regulating valve.

When the regulator is placed in operation, heat from steam in the upper portion of the innergenerator tube causes the surrounding water to flash into steam. This forces water out of theannular space in the generator through the connecting tubing into the metal bellows whichexpands and opens the regulating valve.

If the boiler water level tends to rise, cold water from water storage leg J rises up into theinner generator tube. This cold water plus radiation secured from the fin surface of the outertube causes steam in the annular space to condense, thereby reducing the pressure in theclosed system and allowing the spring to close the regulating valve.

In normal operation, the regulation valve adjusts its position to correspond with the rate ofsteaming as reflected by slight changes in water level and a continuous feed is delivered tothe boiler.

How to Fill Generator When Valve is Above Generator

1. Jack valve open by means of handjack K.

2. Disconnect tubing, R from metal bellows D.

3. Remove Guard H from bellows D, and place bellows in large bucket full of water.

4. Compress bellows many times with open end up until all the air is removed and bellows isfilled solid with water.

5. Insert end of tubing ft in bucket of water along with bellows.

6. Remove generator plug G, and draw on opening until water syphons from bucket outthrough generator.

7. Allow water to run until all air is carried out of line, and then insert plug G.

8. With bellows under water, place Guard H over bellows and connect end of tubing R tobellows. Make sure that end of tubing R and bellows are completely submerged during thisoperation so that no air gets into the system.

9. Replace guard H, and bellows on valve.

10. Release handjack K so that valve spring is free to close valve.

11. Remove generator plug G, and permit excess water to run out.

12. Replace plug G and make sure that connections at both ends of copper tubing, as well asplug G, are made up tight.

* Through the courtesy of Bailey Meter Company, Cleveland, Ohio.

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Fig. 255­­Principle of Operation of Bailey Feed Water Regulator

13. Open valves F and F, and blow down generator by opening valve P.

14. After generator has had time to cool off, regulator is ready for service.

How to Fill Generator When Valve is Below Generator

15. if practical, remove bellows and tubing to an elevation higher than the generator, andfollow same procedure, as when valve is above the generator. If not, jack valve open, removetubing R, and proceed as follows:

16. Remove bellows from valve, and insert in bucket full of water.

17. Compress bellows many times with open end up until all the air is removed and bellows

is filled with water.

18. Place end of copper tubing Q in another bucket of water, and draw on end of coppertubing R until syphon is started.

19. Place end of tubing R in bucket with bellows, and allow water to flow until all air hasbeen washed out of tubing.

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20. Stop flow of water by holding finger over end of tubing Q, and at the same time placeguard H over bellows and connect end of tubing R to bellows. Make sure that end of tubingand bellows are completely submerged during this operation so that no air gets into system.

21. Replace Guard H and bellows on valve.

22. Connect end of tubing Q to generator.

23. Remove plug G from generator, and fill generator with water until it overflows at plug.

24. Release handjack K, and allow excess water to run out.

25. Replace plug G and make sure that connections at both ends of tubing, as well as plug G,are made up tight.

Fig. 256

26. Open valves F and F, and blow down generator by opening valve P.

27. After generator has had time to cool off, regulator is ready for service.

28. Generator should be blown down periodically; once in 24 hours is good practice. Alsogenerator should be blown down whenever regulator is placed in service after the boiler hasbeen out of service.

29.Spring tension on regulating valve has been adjusted at factory so that valve begins toopen when a pressure of 35 pounds per square inch is applied to the metal bellows. Thisadjustment should not be changed.

30. Do riot make up packing nut tight enough to jam valve stem. Make up only finger­tight.

31. Make sure there is no excessive friction or rubbing of regulating valve parts. A mixture ofgraphite and oil applied to guides and valve stem is helpful.

32. The water level carried by regulator is determined by location of generator. As will benoted from a curve, the relation between water level and valve travel varies with changes in

Fig. 257­Section through BaileyFeed Water Regulator Valve

the

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boiler pressure. It may be necessary, therefore, to lowerthe level of generator with respect to normal boilerwater level for higher pressure, and to raise it for lowerpresses. Under average conditions, generator filling plugis located 1 to 1­1/2 inches above normal water level.When deciding on a generator location, it is well toestimate the gauge glass level which will result whenthe valve is in a closed position. This may be done byfollowing boiler pressure line to the left­hand edge ofcurve, and by reading the distance in inches betweenthis intersection and the proposed line of normal gaugeglass level which will be somewhere below the level ofthe generator filling plug.

33. If regulating valve closes completely at too low awater level, this indicates that too little water is in thesystem and that the system should be refilled.

34. If regulating valve does not close completely untilwater level gets too high, there is too much water insystem and a small amount should be allowed to drainout.

35. Water level carried by regulator under normal loadconditions is determined largely by excess of feed­waterpressure. Increasing feed­water pressure raises waterlevel, and decreasing feed­water pressure lowers waterlevel. Best results will be obtained if the excess pressure shown on the valve data sheet ismaintained.

36. If regulator carries a gradually lower and lower water level, this indicates a leak insystem. If leak is not apparent, put a teaspoonful of borax in water and refill. After regulatorhas run for several hours, a grayish mark will appear at point of leakage.

37. Never paint generator or radiator J.

38. Regulator should operate indefinitely without adding water to generator.

39. When it is necessary to add water, close valves F and E and open valve P. After generatorhas cooled, remove plug G and

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Fig. 258 ­­ Section through Bailey Feed Water Valve Body showing construction of Tight

Seating Inner Valve.

add water to overflowing. Make sure the valve is in closed position when this is done.

40. If there is air in system, completely refill in accordance with previous instructions.(Paragraphs 1 to 14 or Paragraphs 15 to 27.)

Installing Winches

DESCRIPTION OF WINCHES

A winch is a mechanically operated device which, by means of a special arrangement ofgearing and drums, pulls a rope, a cable, or a chain at various speeds. (Fig. 259.) These ropes,cables, or chains may be attached to the ship's cargo booms, docking hawsers, or anchors.

The winch mechanism is usually steam­operated.

The operator usually controls the winch by means of throttle and brake mechanisms. Thecontrols are shown clearly in subsequent illustrations.

The drums, or capstans, which are fastened to the drive­shaft extensions are correctly slopedto fit the ropes, or cables, that may be wrapped around the drums. See Fig. 259. The smalldrum "t", Fig. 259, is grooved to receive a wire cable. This drum and the drum on the portside are sometimes used for emergency steering. When the power is applied to the winch, therope or cable winds up, and a pull will be exerted upon whatever is fastened to the other endof the rope. The object on the other end of the rope will have a tendency to move toward thewinch.

210

Fig. 259­­Starboard Side of After Deck Winch

CLASSIFICATION OF WINCHES

Winches are classified according to their use or location. An anchor winch (Fig. 260), used toraise the anchor, is located within a reasonable distance of the anchor. A stern mooringwinch, located at the stern, is used to take on mooring lines. Deck cargo winches are locatedamidships and on forward decks. As the name implies, cargo winches are used to load andunload cargoes.

Winches are often used for purposes other than those for which they were originallyintended; for example, a cargo winch located amidships might conveniently be used as amooring winch, fore, aft, or outboard. This use is made possible by means of blocks androllers over which the rope or cable applies its pull in a change of direction.

A WINCH SETTING

Some winches are set on special foundations; others can be set on the foundation or skid justas built by the manufacturer. All setting up and securing of a winch on the foundation mustbe done in a manner that will not warp or bind the working parts of the mechanism. For thisreason the locations for the bearing brackets must all be laid out carefully to the center lines,as shown on the blueprint. A typical bearing bracket is shown in Fig. 261.

The bolt holes for the bracket feet are easily drilled from the outside of the bracket, straightdown through the channel filler or base. See "a", Fig. 261. All bracket feet are not the samein this respect.

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Fig. 260­­Typical Anchor Winch on Forward Deck

An example of another type of bearing bracket is shown in Fig. 262. Notice that in this casethe bolt hole is located under the sloping flange of the bearing bracket at "b". The bolt holesfor the feet cannot be drilled through while the bearing bracket is in position.

SETTING AN ANCHOR WINCH

The location for an anchor winch is laid off by theshipfitters. Flat bar is correctly placed and welded to thedeck so as to form a band around the winch foundationarea. Flat bar is also correctly placed and welded to thedeck around the chain locker bell mouths. See Fig. 264.

The ship carpenters build a wooden foundation inside of

Fig. 261­­Bearing Bracket

Fig. 262­­Bearing Bracketwith Inside Bolt Holes

Fig. 263­­Bolt Holes Laid Out

the band area upon which the winch is to be bolted down.

The setting of an afterdeck winch differs in some respectsfrom the setting of an anchor winch and will be explainedfully under the heading, "Setting a Deck Winch".

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TOOLS AND EQUIPMENT

1. Number 4 corner air­drilling machine

2. Drillsa. 1 full­lengthb. 1 half­lengthc. 1 12" extension (the sizes of the drills depend on theholes in the base of the winch)

3. Shipfitter's taper reamer (bolt­hole size)

4. Chalk line

5. Center punch

6. Full set of wrenches

7. 1 3/4­lb. hammer

8. 6' tape

9. 50' tape

10. Pocket knife

MATERIALS

2 round steel bars 18" long (These bars mustfit the hole in the winch base easily, butsnugly.

Red leadTarred feltTack GrommetsStuds WashersNuts

Fig. 264­­Layout for Chainlocker Bell Mouths

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The job of setting an anchor winch may be outlined as follows:

PROCEDURE

1. Find the center between the two chain­locker bell­mouths in the deck.

2. Snap a chalk line "a­a" fore and aft on the wood foundation, parallel with the center line ofthe ship, and passing through the center between the chain­locker bell­mouths in the deck.See Fig. 264. Distance "W­W" is the same length.

3. Snap a second center line "b­b" at right angles to center line through port to starboardcenters of the chain locker openings.

4. Locate a fore­and­aft center line on the base of the winch. Measure from port to starboardon the base of the winch, find the center of the base, and center punch mark the, edge of thebase. Do this fore and aft.

NOTE: There are openings in the winch base, port and starboard, through whichthe anchor chains fall so that they may be stowed in the chain lockers below decks.These openings must line up with the chain­locker openings in the deck. Theoutboard edges of the winch base must he marked with a center punch so that thecenters of the openings in the base can be set exactly over the line which was ­snapped on the foundation in step 3.

5. Measure the distance from the forward edge of the winch base to the center of the chainopening in the base.

6. Lay off this distance on the outboard edges of the winch base and mark with center punch.

NOTE: These center line marks on the winch base must correspond with the chalkline which was snapped on the wood foundation.

7. Have the winch set by the riggers.

NOTE: The ship riggers set the winch on this foundation under the supervision ofthe outside­machinist leader.

8. After the winch has been set by the riggers, go below into the chain locker and inspect thealignment of the winch­chain holes with the chain­locker openings. The centers whenchecked are equal fore and aft and port and starboard. Adjust the winch if necessary.

9. When the winch has been adjusted to the proper location on the foundation, have thecarpenters inspect the wood foundation.

NOTE: At this point the ship carpenter checks the fit between the base of thewinch and the wood foundation for high spots.

10. Drill all bolt holes, using the holes in the base of the winch as a guide. The holes aredrilled through the wood foundation and through the steel deck. Check carefully whendrilling to make sure that there are no electric cables immediately beneath the holes. Consultthe leader if there are obstructions.

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Fig. 265­­Cutting the Tarred Felt Around the Bolt Holes

11. Mark through all holes that cannot be drilled through the base of the winch.

NOTE: Some parts of the base are heavier than others. Where the thickness doesnot exceed four or five inches, the hole locations may be marked with a pencil.Where the thickness runs perhaps as much as ten inches, a drill is inserted throughthe hole in the base and the hole is "spotted". All the holes should have beendrilled or spotted at this point.

12. The riggers lift the winch off the foundation, and the holes that could not be drilledbefore are drilled now, using the "spotted" points to start the drill.

NOTE: The carpenter trims off the high spots of the wood at this time to insure agood fit between the wood foundation and the winch base.

13. After all the holes are drilled, paint and soak the wood with red lead.

14. Cover the wood foundation surface with tarred felt, and tack it down securely withnumber ten tacks. Special attention is given to tacking the corner of each sheet of tarred felt.(These tarred felt sheets come in rectangular pieces 2' x 4' x 1/8" thick.)

15. Cut holes through the felt to match the bolt holes bored in the foundation.

NOTE: Find the location of each hole with the fingers, and cut through the feltwith a sharp knife. Follow the side of the hole in the wood foundation, and trim thefelt fully as large as the hole. See Fig. 265.

16. Have two round steel bars at hand. (See materials)

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17. Soak the entire felt surface with red lead.

18. Have the riggers lift the winch and swing it over the foundation. Lower to within threeinches of the painted surface.

19. Insert each one of the steel bars in opposite corners of the winch base through an "openhole".

NOTE: "Open hole" means a hole that is so located that the bar may be easilyremoved after the winch is set on the foundation.

20. Swing the winch until the hole through which the steel bars are inserted correspond withmatching holes in the foundation, and enter the bars in the foundation holes.

21. Lower the winch. The steel bars guide the winch to the correct setting.

22. Remove the steel bars.

23. Number each hole in the base of the winch.

NOTE: Start numbering the holes at the port side forward; proceed aft and allaround the winch base to the starting point.

24. Measure the length of the bolts required for each numbered hole, and list the sizes on aconvenient scratch pad.

NOTE: Measure each hole from the top of the base to the underside of the deck.To this dimension add sufficient length to allow for a nut and a half­nut on the topof the base; allow for a grommet, washer, and nut below deck. (For example: a bolt1­1/2" in diameter requires 2­1/2" on top and 1­3/4" below. If the "metal to metal"length measures 8", then the total length of the bolt will be 8" 2­1/2" 1­3/4" 12­1/4".) The leader, however, usually checks for the bolt length. There must be 1/2"more thread on the respective bolt ends than is required for the thickness of thenuts.

25. Order studs from the machine shop. These studs are made of special steel.

26. Go below deck, and with the corner air­drilling machine ream all the bolt holes in orderto take care of misalignment and clear the holes of slivers.

27. Install all the studs beginning at the inboard holes. Tighten each stud reasonably tight.Check with the leader.

28. Have the entire job inspected.

SETTING AN AFTERDECK WINCH

An afterdeck winch is located on the poop deck aft of the galley. The outside machinist boltsthe foundation angles to the base of the deck winch according to the blueprint. Shipfitters layout the location for the winch and then set it. The shipfitters tack weld to the deck and thenbrace the angles which the outside machinist bolted to the winch base. The winch is thenlifted from the angles, and the foundation is completed by the shipfitters; brackets and strutsare welded in place to stiffen and make the foundation solid.

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When the shipfitters have completed the foundation, the outside machinist levels off thesurface of the winch base. The painters are then notified to apply a coat of suitable protectivepaint. The foundation is now ready for the setting of the winch.

CAPSTAN SHAFTS

This type of winch is equipped with capstan shafts that extend some distance beyond thewinch. Port and starboard couplings connect the capstan shaft to the main driving shaft.These shafts may extend for as much as 4 feet and are supported port and starboard by one ormore bearing pedestals. The bearing pedestals (called bearing brackets) are set to carry thecapstan shaft in correct alignment with the main driving shaft. Suitable foundations areplaced under the feet of the bearing pedestal, and they are welded to the deck. Bearingbrackets are bolted to these foundations with fitted chocks between foundations and pedestalfeet. See Figs. 252, 266 and 271.

Fig. 266­­After Deck Winch Showing Controls

Figure 266 shows the starboard side of an afterdeck winch. The foot pedal "a" controls thebrake. The hand lever "b" controls the motive power. The foundations are formed in theblacksmith shop. A flat plate approximately 1/2" thick, and of the correct size, is heated andbent to the channel shape shown in Fig. 263. The flat top of the foundation is then planed offlevel and true in the machine shop. It is on this machined surface that the locations for the

bracket feet are laid out. In Fig. 263 are shown center lines which indicate the center of thefoundation lengthwise and crosswise, and the centers of the bolt holes.

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TOOLS AND EQUIPMENT

1. Portable grinder2. 8" outside calipers3. 8" inside calipers4. Full set of wrenches5. Drills (diameter of the drill depends on the diameter of the boltholes in the winch base and brackets)6. Shipfitter's taper reamer (bolt­hole size)7. Center punch8. 1­3/4 lb. hammer9. 6' tape10. 50' tape11. 14" second­cut flat file12. No. 4 corner air­drilling machine13. 14" square bastard file14. Thickness gauge15. C­clamps16. Scriber17. Dividers18. Oilstone19. Spoon­bearing scraper20. Hermaphrodites

MATERIAL

Garlock packingChalkBoltsNutsWashersPiece of 1­1/16" roundstock 6" long

The job of setting an afterdeck winch may be outlined as follows:

PROCEDURE

1. Procure from the shipfitter the side angles upon which the winch is to be set.

2. Block up the winch about one foot high all around.

3. Chalk one leg of each side angle for the entire length and clamp the chalked side to thewinch base in a fore­and­aft position, one angle to port and one angle to starboard; place thelegs of the angles inboard with the edges of the angles extending beyond the winch baseabout 1/2". See Fig. 267. The ends of the angles project beyond the winch base about 1­1/2"fore and aft. Divide the distance so that the angles project the same amount fore and aft, evenif the distance is more or less than 1­1/2".

Fig. 267­­Winch Base Blocked Up for Placing Side Angles

Fig. 268­­Marking Bolt

Hole Centers

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4. Scribe through the holes in the winch base, and mark the locations of these holes on theangles.

NOTE: Scribing the hole locations must be done very carefully because there is noroom to use a reamer to line up the holes after they are drilled.

5. Mark the angles on one end, and place a similar mark on the winch base above the angles(make the mark with the center punch). This will enable the mechanic to replace the angles inthe correct location.

6. Remove the angles, and make four similar punch marks, spaced equally around thecircumference of each bolt hold circle. See Fig. 268.

7. With the dividers, find the center of the scribed circle. SeeFig. 82 "Removing Broken Studs and Bolts", Part I, for methodof procedure.

8. Center punch the center at the intersection of the divider lines.

9. Drill a 3/8" pilot hole through all centers. See Part I,"Reaming Through Holes", Fig. 64, for pilot­hole procedure.

10. Select a drill of the same diameter as the hole in the winchbase, and drill through the pilot hole.

11. Measure for the bolt lengths, and allow for a nut, plus 1/2"beyond the actual thickness of winch base and angle.

12. Check for the proper angle location (See step 5), and bolt the angles to the winch base.

NOTE: The shipfitters have laid out the location of the winch on the poop deck.

13. Have the ship riggers lift and place the winch on the previously laid out location on thedeck.

14. Have the shipfitter level the winch and weld the angle edge to the deck. The outsidemachinist leader checks the job for correct installation at this point.

15. Remove the bolts, and lift the winch off the foundation so that the foundation may befinished by the shipfitters.

NOTE: The shipfitter welds gussets, angles, and cross plates in position to stiffenthe foundation.

16. Grind off the top of the foundation all welding burrs which might interfere with the levelfit between the Winch base and the foundation top.

17. Notify the painter, and have the foundation painted with anti­rust solution.

18. Set the winch back on the foundation. Bolt securely, and lock all bolts with half­inchnuts.

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19. Remove the fitted bolts from the main drive shaft of the winch, and clean the bearingsurface. Check for and remove any rough spots with the oilstone.

NOTE: To avoid losing the fitted bolts, wire them together and wire the bundle tothe winch.

20. Check the number which is stamped on the main shaft coupling, and find the matchingnumber on the capstan shaft coupling.

Fig. 269­­Blocking of the Capstan

Fig. 270­­Spigot Coupling Support

21. Have the riggers block up the capstan. Whenthis operation is complete, line up the capstan asclose as possible with the main drive shaft. Thecapstan should be blocked with two wooden wedgesto prevent it from shifting.

NOTE: The inboard end of the capstan shaft is heldtemporarily by the spigot coupling. One bolt isplaced loosely through the coupling to preventslipping. See Fig. 270.

22. Layout center lines on the top of the channelfoundation as shown in Fig. 263.

23. Locate the center of the bearing bracket on theedge of the base, fore and aft, port and starboard.Center punch these centers. See "x" and "y". Fill.271.

24. Place the bearing­bracket center on the channelfoundation center. Center the bracket on the channelfoundation fore and aft, port and starboard, to matchthe center­punch mark and the center lines.

NOTE: Chalk the machined surface of the channelfoundation so that the "lay out" lines will stand outclearly.

25. Scribe through the holes in the bearing bracket.Mark the foundations and the base of the bearingbracket so that the locations will not be lost.

26. Center punch the circumferences of the holes asin step 6, and locate center as in step 7.

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Fig. 271­­Marking the Rearing Bracket Centers

27. Center punch mark at the intersections of the divider lines.

28. Drill 3/8" pilot holes through the centers.

29. Select a drill of the same size as the diameter of the hole in the bearing­bracket base, anddrill pilot holes through.

30. Clean up the machined bearing surface on the capstan shafts, and stone any rough spots.

31. Remove the cap from the bearing bracket, and clean any rough surfaces carefully.

32. Apply grease to the shaft­bearing surfaces.

33. Slide the bottom half of the bearing bracket on the shaft, and block up temporarily.

Fig. 272­­Placing Garlock

Packing

Fig. 273­­Coupling Face Allowance

34. Place a piece of garlock packing at the top side of the shaft on the bearing surface. Thispacking should be the width of the bearing and about 1/3 of the shaft circumference inlength.

35. Replace the base cap on the bearing bracket over thegarlock packing.

36. Bump the bearing bracket out to the capstan hub toclear the shaft of the hub about .030 of an inch.

37. Tighten the bearing cap on the garlock packing so asto draw the bottom half of the bearing bracket tight to theshaft. See Fig. 272.

38. Check the coupling between the main drive shaft andthe capstan shaft. The bottom of the coupling should belined up at the bottom .003 "open", and about .015between the faces of the couplings. See Fig. 273.

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39. Check the marks on the foundation with the marks on the bearing bracket, and slide thecorrect foundation under the bracket. If the foundation is too high to set, have it rough­burned off until it will slide under easily.

40. Bolt the foundation to the bottom of the bracket with temporary bolts. Draw the bolts uptight.

41. Chalk the foundation about. 1" above the deck on both sides for the entire length.

42. Re­check the coupling for clearance as shownin Fig. 273.

43. Measure with the square, and level thefoundation with the deck fore and aft.

44. Set the "morphs" to 1", and scribe on thechalked surfaces parallel lines on both sides of thefoundation.

45. Remove the bolts, and remove the foundation.

46. Center punch mark the foundation along thescribed lines on both sides 1­1/2" apart.

47. Have the foundation burned off to these center­punched lines.

48. Knock off the slag and rough sides of the burned edges with a hammer.

49. Slide the foundation back to the former position under the bracket, but on the deck,leaving a 1" space between the top of the foundation and the bottom of the bracket.

50. Insert two pieces of round stock, easy bolt­hole size, through the bolt holes in theopposite corners of the bracket base and the holes in the foundation. This operation will serveto line up the foundation holes with the bracket holes.

51. With fox wedges, raise one side of the foundation until it is 1­1/16" higher than the otherside, thus forming a wedge­shaped space between the foundation and the bracket base.

52. Re­check the coupling for clearance as in Fig. 273.

53. Have the welders tack all four corners of the foundation to the deck.

54. Re­check the wedge­shaped space as in step 51 to make sure that the foundation is 1/16"higher on one side than it is on the other side.

55. If correct, weld the foundation to the deck inside and outside for the entire length.

50. Place heel wedges between the foundation and the bearing bracket, two forward and twoaft. The bracket is now supported on the heel wedges.

57. Remove blocking from under the capstan.

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58. Use a piece of scrap metal to make a strongback to lay across the bracket edge. Drillholes for the bolts. Place two bolts long enough to pass through the strongback and reach tothe deck. Weld the bottom end of the bolts to the deck. Place nuts and draw down tight. SeeFig. 271.

59. Weld a piece of flat bar to the deck aft of bearing bracket about 2". A hole is drilledthrough the plate bar for a bolt. The bolt is used as a backing screw to prevent the bracket'sdrifting aft. See Fig. 274.

Fig. 274­­Using a Flatbar Stop and an Adjusting Screw

60. Check all adjustments for alignment; readjust if necessary.

61. Take chock sizes and order chocks.

62. Fit chocks.

63. Scribe holes in chocks, and have them drilled.

64. Place chocks, install the bolts, and draw down tightly. Lock with the half­nuts.

65. Remove the heel wedges.

NOTE: Repeat on the opposite side of the winch all of the steps hereinenumerated. Both sides are worked together.

66. Re­check coupling. See Fig. 273. If the alignment is the same as it was before, have theinspector approve the job. If the coupling is out of alignment, the chocks will have to berefitted.

67. Drill and install 1/2" dowels on opposite corners of the bearing brackets. See Fig. 275.

NOTE: The dowels are turned .502 of an inch in diameter and threaded for 3/4 ofan inch on one end. The thread is for the purpose of removing the dowel ifnecessary. The dowel must be long enough below the thread to pass through thebracket and the foundation. The threaded end of the dowel must be undercut toform a shoulder, and the end must be slightly rounded as in Fig. 275 at "b".

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Run a nut on the threaded end of the dowel flush with the shoulder before starting to drivethe dowel into place. This nut will prevent mushrooming the end of the dowel under thehammer when the dowel is driven into place.

Drill the dowel holes with a 31/64" drill. After drilling, ream through with a 1/2" handreamer. The dowel should drive in with medium force.

68. Remove the bearing­bracket cap, and take out thegarlock packing.

69. Clean out the bearing cap. Clean up the shaft.

70. Grease the shaft, replace the bearing cap, andtighten down.

Fig. 275­­Drive Fit Dowel

71. Check with the feelers and allow .012 of an inchclearance between shaft and bearing. If more than.012, remove a shim. If less than .012, add a shim.

72. Clean up feed bolts and coupling.

73. Drive fitted bolts through coupling, and draw allnuts down snugly.

74. Drill and dowel the base of the deck winch on thefoundation.

75. Grease the entire mechanism, and prepare it foroperation.

Installing A Steering Gear and Telemotor ForPilot House Indication

GENERAL DESCRIPTION OF MAIN STEERING GEAR

The main steering gear controls the position of the ship's rudder. A ship's rudder weighs asmuch as 24 tons and steering the ship by hand as is done in a small pleasure boat is notpossible.

A mechanically operated device which is known as a steering gear is installed in the afterpeak on a deck called the steering­gear flat. Certain motors, pumps, and other mechanismsare installed on the steering­gear flat which control the operations of the steering gear.Control wheels are installed in the wheelhouse and on top of the wheelhouse. Thewheelhouse is located on the navigating bridge deck.

Other control wheels are located on the steering­gear flat forward of the main steering gear.The control wheels actuate the steering mechanisms by means of hydraulic power which istransmitted from control wheel to steering gear through a pipe line connecting thewheelhouse with the steering­gear room. Hence, the entire installation is known as the ship'ssteering gear. The port side of the forward end of the steering­gear engine is shown in Fig.276.

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Fig. 276­­Port Side of Steering Gear in Steering Gear Room

ALIGNING STEERING GEAR MECHANISMS

The entire steering­gear mechanism is lined up with the center line of the rudder stock.Hence, the rudder must be placed and the rudder stock installed before the work of installingthe steering gear may begin.

Figure 277 shows the rudder (a), the rudder stock (b), the rudder trunk (c), the carrier bearing(d), the bearing disk (e), the carrier and brake drum (f), the tiller (g), and the keeper ring (h),installed in position. All of these parts must line up with the rudder stock center line fore and

aft, port and starboard.

The procedure for the installation of these parts up to the point where the installation of thesteering gear commences is as follows:

1. Weld the rudder trunk (c) in position as shown.

2. The rudder is placed and the gudgeon pins installed as shown in Fig. 277 at "z".

3. The rudder is raised and a steel block 2" thick is inserted between the upper gudgeon eyeand the rudder to hold the rudder in this raised Position. See Fig. 277 at "x".

4. Install the rudder stock (b).

5. Install the carrier bearing (d).

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NOTE: The carrier bearing is bolted to the rudder trunk.

6. Install the bearing disk (e).

7. Install the carrier and brake drum (f), and have the brake hand in position on the brakedrum to be connected to the brake lever later.

NOTE: The two halves of the carrier and brake drum are not tightened snugly untilthe rudder is lowered into working position.

8. Install the tiller (g).

9. Install the keeper ring (h).

10. Lift the rudder enough to remove the 2" block which was placed to raise the rudder inStep 3.

11. Lower the rudder into position so that the rudder carrier takes the entire weight of therudder assembly.

12. Tighten the bolts through the two halves of the rudder carrier and brake­drum casting,securing the carrier to the rudder stock.

13. Swing the rudder to port and starboard and check it against the rudder stops for thecorrect angle with the ship center line. If the angle is not correct, add to or take away fromthe rudder stops.

14. Bring the rudder to amidship position and secure with chain falls from the tiller to theshell of the ship. 15. Install the packing and the split packing glands shown at "j", Fig. 277.

INSTALLING MAIN STEERING­GEAR RAMS AND CYLINDERS

The foundations for the main steering­gear ram and cylinders are "A" "A" "A", Fig. 279.Figure 281 shows this unit extending athwartships. Note the two heavy bolts, "B" "B" whichact as a support for the follow­up gear bearing and pinion. These bolts are shown at "B", Fig.280 and at "B", Fig. 282. The bolts tie the port and starboard rams and cylinders together andensure their correct alignment.

The foundation tops, Fig. 279, "A", "A", "A", are rough­leveled off with a portable grinderand finish­ground with a portable surface grinder. The surfaces of the foundation tops areground level and smooth for a distance of approximately 10" from the edge, fore and aft.This 10" level plane surface slopes from nothing to the outside about 1/64 of an inch, but notmore than 1/32 of an inch. A long straight edge is used to check the amount of slope. See Fig.287.

This procedure is carried out on all the foundation tops shown in Fig. 279, "B"­"B", "C"­"C","D", "E", "F", and "G".

The shipriggers pick up the main unit and lower it to the foundation "A" "A". The unit is thenleveled and brought to the correct position fore and aft, port and starboard. The job is nowready to have the chocks fitted and the bolts installed through the base. This main ram andcylinder unit must be in place before proceeding to install any of the other parts of thesteering gear.

226

Fig. 277­­Rudder Stock Tiller and Steering Gear

227

Fig. 278­­Cast Steel Rudder Trunk

228

Fig. 279­­Foundation Plan for Main Steering­Gear Rams and Cylinders

229

Fig. 280­­Plan View of Steering Gear Installed on Steering Gear Flat

230

Fig. 281­­Main steering­Gear Ram and Telemotor

16. inspect the position of the ram in the cylinders, and make any necessary adjustment tobring the pivot hole in the ram to the fore­and­aft center line of the ship.

17. Weld angle clips at convenient places to clear the corner chock positions at points shownat "a", Fig. 286. Complete the welding of angle clips to both main ram foundations.

NOTE: Angle clips are welded to the foundations in this manner so that heavysetscrews may be used through the clips to adjust the unit fore and aft, port andstarboard. The clips must be drilled and tapped for 3/4" bolts.

18. Drill holes for 3/4" jacking screws through the base of the unit as shown in Fig. 289 at"b" according to the dimensions given. See Fig. 277.

19. By means of the jacking screws through the unit base and the set screws through theangle clips, adjust the position of the main ram and cylinder until the athwartship center lineof the ram is at right angles to the vertical center line of the rudder stock and at right anglesto the fore­and­aft ship center line. See Fig. 277, 90° angles. (See Fig. 280).

NOTE: Figure 290 at "g"­"g" tiller jaws, shows a dimension "n". The distancefrom the top side of these tiller jaws to the center is the same. The center of thesteering­gear main cylinder must be at a point 1/4" below this

231

Fig. 282­­Front View of Steering­­Gear Looking Aft

center, which is between the top and bottom of the tiller jaws. See Fig. 277 at "g", Fig. 282,and Fig. 290 at "g".

20. Begin at the inboard, forward corners of the port foundation ("d", Fig. 286, Chock #1),and measure for chock sizes. Fill out a chock sheet for each chock.

NOTE: The position of each chock is numbered 1, 2, 3, 4, etc. Number each chockand its position with white paint. Mark the position of the chock on the base of theunit. Chock #2 is the next one to port. Follow in this direction (to port), and gocompletely around the foundation' to the inboard and aft corner. Go across to theStarboard and aft corner of the starboard foundation, continue from the inboard,after corner, and go completely around the foundation to the inboard, forwardcorners. See Fig. 286 for location of the chocks. There is a chock for every bolthole. See Fig. 276.

21. Send the chock sheets to the shop, and order the chocks machined according todimensions given on the sheets.

22. When the chocks are returned to the job, begin fitting the correct chocks as follows:

232

Fig. 283­­Hele­Shaw Hand­­Steering Pump

233

Fig. 284­­Plan and Elevation of Telemotor Copper Piping

See explanation of numbers on page 245

234

Fig. 285­­Differential Follow­Up Control.

235

Fit #1 chock 1st. (See Step #5)Fit #7 chock 2nd.Fit #8 chock 3rd.Fit #14 chock 4th.

(These chocks are on the port foundation.)

Fit #15 chock 5th.Fit #21 chock 6th.Fit #22 chock 7th.Fit #28 chock 8th.

(These chocks are on the starboard foundation.)

Fig. 286­­Port Foundation for Main Steering Ram

NOTE: Corner chocks are fitted first as outlined above because they will thenserve as a reference when fitting intermediate chocks. Example: when numbers 2,3, 4, 5, and 6, are being fitted the base of the unit could easily he raised and the job

Fig. 289­­Adjusting Screw Through Base

thrown out of line. As each chock is fitted, the corner chocks are checked with athickness gauge to make sure they are tight. The corner chocks should be checkedfrequently while the other intermediate chocks are being fitted.

23. Fit the intermediate chocks.

Fig. 287­­Checking Foundation Top with a Straightedge

236

Fig. 288­­Jacking Screws Tack Welded to Foundation Top

24. Scribe through the holes in the unit base on all eight corners, and mark the position of theholes which are to be drilled in the corner chocks.

25. Remove the corner' chocks, and center punchmark the circumference of each hole. Find thecenter of the holes with the dividers; center punchmark the centers; and send the chocks to themachine shop for drilling. Give the machine shopthe size of holes required.

26. When the chocks are returned, place them inposition and drill the holes through the foundation,using the hole in the unit base for a guide. See Fig.61.

BILL OF MATERIALS

A partial bill of materials which goes into the fabrication and assembly of a steering engine isgiven below. To identify the type and grade of material; compare the key­number on theFigures 284, 297, 299, with the bill of materials.

For example: The number 12 in the circle in Fig. 297 is found in the column at the left in thebill of materials. Reading across from

Fig. 290­­Tiller Jaw Center 1/4" Above Ram Center

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Fig. 291­­Pump and Motor Unit Foundation

the number, we find 3/4" standard 900 Ell, brass. In the small circles on Fig. 297 will befound the number 12. Each number 12 on the Figure means that the materials given opposite12 in the bill of material are to be used at that point.

Follow this same procedure with all the other numbers in the circles in these three figures.

In Fig. 277 the letter "s" is found in one of the circles. This material is 1" square packing.

NOTE: When because of limited working spaceit is impossible to drill a full­sized hole in thefoundation, the workman places a bushing inthe hole in the unit base and drills a pilot holewith a small drill. It is then possible to getunder the foundation with a large drill and adrilling machine and drill the hole to the fullsize from below.

27. When the corner holes are drilled, reamthem to size as shown on the blueprint.

28. Order 28 fitted bolts to fit the reamed holes.Give the machine shop the sizes of the bolts.

29. When the fitted bolts are ready, install them on all eight corners first and draw up snugly.

NOTE: The corner bolts are fitted first to prevent any possible misalignment of theunit.

30. Scribe through the unit base holes, and mark the hole locations on all the intermediatechocks. Locate the centers as in step 10.

31. Send the chocks to the machine shop to be drilled. Give the shop the size of the hole.

32. When the chocks are returned, install them in the correct location and ream as in step 12.

Fig. 292­­Telemotor Foundation

238

33. Install the remainder of the fitted bolts, and pull them up snugly.

34. Install port and starboard motor and pump units "k" (See Fig. 280, Fig. 281, Fig 282)according to the blueprint.

NOTE: Follow­up gear "L" must be installed and lined up at the same time themotor and pump units are installed. This is done to insure the correct alignment onall three units. These units are lined up with jacking screws for height and positionas was done when lining up the main cylinder and ram units. See Fig. 289.

35. Fit, the chocks and install the fitted bolts as was done with the main cylinder and ramunits. See Fig. 291 for location of bolt holes.

INSTALLING THE TELEMOTOR

Figure 284 at "p", shows two small lugs connected by a pin. The pin must he a slip fitthrough both lugs, and it must slide easily. The forward lug is connected with the follow­upgear and the after lug is part of the telemeter leg which is connected o the telemotor.

The foundation for the telemotor is shown at "e", Fig. 279. The telemotor is shown at "t",Fig. 277, and at "t", Fig. 280. The telemotor must be installed on the foundation and alignedwith the follow­up gear. Figure 285 shows the follow­up gear and the pin at "c". See Fig. 292

Fig. 294­­Emergency Hand­SteeringCylinder and Ram Foundation

for location of bolt holes in the foundation.

Fig. 293­­Telemotor Rack Foundation

PROCEED

36. Install the telemeter rack and align with the follow­up gear. See fig 279 at "d" forlocation.

37. Chock the telemotor and bolt down. See Fig. 293 for location of bolt holes.

35. Install the telemeter and align it with the telemeter rack.

39. Chock the telemeter and bolt down.

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NOTE: Check frequently to insure the sliding fit of pin "p". Figures 277 and 284.

40. Install the follow­up gear universal control rod "U", shown in Figs. 277 and 280.

NOTE: Figure 292 shows two chocks at "h­h" which do not have bolts. Thesechocks act as a support under the telemotor, midway between the end chocks, andare tack welded as shown at "w­w". Care must be taken to have the welders tackthese chocks to the foundation.

EMERGENCY, HAND­STEERING MECHANISM

Figures 277, 280, and 284 show the emergency, hand­steering cylinder and ram. Figure 279"R" shows the foundation for these parts.

41. Install the emergency, hand­steering cylinder and ram units, and align the center line ofthe unit in the same manner as was done in step 4 in aligning the main ram and cylinder. SeeFig. 294 for location of bolt holes.

42. Chock the unit, and bolt down.

BRAKE­LEVER UNIT

In step 7 the brake band was installed to be connectedto the brake lever later on. The brake­lever unit isnow to be installed. Figure 279 at "f" shows thefoundation for the brake­lever unit. Figure 280 at "v"shows the brake­band connection with the brake­lever. Figure 280 also shows the brake­leveradjusting screw at "w". The adjusting­screw unitmust be installed at the same time as the brake leverin order to secure a correct alignment. Figure 303shows

Fig. 296­

Screw Foundation

Fig. 297­­Hand­Steering Pump Foundation

Fig. 295­­Brake Foundation

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the brake, the brake lever, and the brake­adjusting screw assembled on the foundations, inFigs. 295 and 296.

INSTALLING THE BRAKE LEVER AND SCREW

The brake lever and the brake­lever adjusting­screw units are nowinstalled and aligned with the brake band which was previously placedin position on the brake drum. The brake edges must line up with theflanges on the brake drum and not "cross" the plane of the brake­drumflanges. When the alignment is correct, the bottom edge of the brakeshould clear the bottom flange of the Crake drum about 1/16 of an inch.The base of each of these units is adjusted to the correct height withjacking screws. When the alignment is correct, the chocks are fitted,drilled, reamed, and bolted down according to standard procedure.

HAND PUMP AND FILLING TANK

Figure 298 shows a hand pump and a filling tank both of which are parts of the telemotorsystem. The liquid for the hydraulic mechanism is poured into the tank, and the pump is usedto circulate the liquid and distribute it throughout the telemotor lines. The foundation for thepump is two 3" angles welded to the deck after the pump has been bolted to the angles. Anangle foundation for the tank is welded to the deck, and the tank is strapped down securely.

HELE­SHAW HAND­STEERING PUMP

Figure 280 at "y" shows a hand steering pumpwhich is used for emergency steering when theelectric power fails on the main unit. Turningthe hand wheel operates the pump which in turnoperates the emergency rams "R­R", Fig. 280.

The unit is bolted to the foundation, withoutchocks. A shim may be used to compensateunevenness in the foundation.

The holes in the foundation are located from thebase of the unit which is already drilled whenreceived. See Fig. 297 for the locations of theholes in the foundation. The unit is lined up withthe bulkhead.

STEERING­GEAR CONTROL

Figure 299 shows the steering­gear control inthe wheelhouse and on the wheelhouse top. Figure 300 is a cross­section view of the base ofthe steering­gear column in the wheelhouse. Figure 301 is a cross­section view of the base ofthe steering­gear column on the wheelhouse top. Bosses are welded to the deck as at "a".Studs are screwed into the

241

Fig. 298­­Plan and Elevation of Telemotor System in Steering Gear Room

See explanation of numbers on Page 245

242

Fig. 300­­Telemotor Column Base

in the Wheel House

Fig. 299­­Elevation of Telemotor Piping System Connected with the Wheel­House Controls

See explanation of numbers on Page 245

243

bosses, and teak­wood blocks about 3" thick areplaced as shown. The forward telemotor is installedshown in Fig. 300 and bolted down. The steering­column shaft is connected to the telemotor by meansof a clutch. either steering wheel can be used tooperate the telemotor and so control the steeringgear. The forward, telemotor­unit filling tank isinstalled as shown in 299.

The installation is now ready for piping. Thecoppersmiths connect the piping from the forwardtelemotor on the bridge to the after telemotor. Thecoppersmiths also install the piping between thefilling, tank and the telemotor.

The installation is now ready for trial operation.

Figure 302 is part of a steam­operated steering gearshowing telemotor­to­throttle­valve control andtrick­wheel control.

Fig. 301­­Telemotor Column Baseon the Wheel House Top

Fig. 302­­Steam Operated Steering­­Gear

244

Fig. 303­­Brake Lever Unit

See explanation of numbers on Page 245

245

EXPLANATION OF NUMBERS ON FIGURE 284

No.1 1" Fig. (600#) ­ F.S. Male End Slip on Type 241­585­52 17 Fig. (600#) ­ F.S. Female End Slip on Type 214­585­53 1" Tubing Seamless Steel Ex. R.Y. IPS4 1" Welding Tee ­ Seamless Steel Ex. H.Y. Pipe Thkss.5 1" By Pass Valve F.S. 21­1­958­5

EXPLANATION OF NUMBERS ON FIGURES 298 and 299

No.6 Coupling C.R.S.7 Telemotor Pipe S.D. Copper8 3/4" Std. Union Brass9 3/4" Std. Scr. Globe Valve Brass10 3/4" Pipe Brass11 3/4" x 3/4" x 3/4" Std. Tee Brass12 3/4" Std. 90° Ell Brass13 1/2" cock Brass

14 1/2" Nipple Brass15 Male Connector 5/8" tube size16 Union Nut 5/8" tube size17 5/8" O.D. Tubing S.D. Copper18 Bracket Comp. "G"19 Coupling Brass20 Shaft, 1­7/16" diam. Brass21 Union Elbow 5/8" tube size22 Stuffing Box Complete23 Flat Bar Steel24 Blocking Teakwood

EXPLANATION OF NUMBERS ON FIGURE 303

No.26 Brake Lever ­ C.S. 175­958 51/1 ­ Annealed27 Bracket Steel Complete28 Bearing C.I. 5­930 92/329 Nut Comp. "G" 37­383­55130 Spindle F.St. A.R.S. Grade 4231 Brake­Band EHD F.St. A.B.S. Grade ,4232 Brake Band Steel Flat bar­7/8 x 1­3/4 x 14'­0" long.33 Bracket St.Pl 5" x 4" x 1/2" each

246

Installing A Propeller And Tail Shaft

THE PROPELLER

The propeller, Fig. 304, is usually a bronze casting weighing approximately seventeen tons.The propeller casting is balanced, and the hole in the hub for the tail shaft is bored in themachine shop. A template is used when boring the propeller, the use of which should insure aperfect fit between the tail shaft and the propeller bore.

Fig. 304­­Typical Bronze Propeller

THE TAIL SHAFT IS PLACED FIRST

The tail shaft, Fig. 305, is lowered into the engine room by the ship riggers and passedthrough the stern until flush with the eye. The propeller hub and tail shaft must be free of dirtand grit when placed together.

Fig. 306­­Key and Keyway Aligned to Fit.

Fig. 307­­Lock Nut on Tail Shaft

Fig. 308­Locking Device

Fig. 305­­Tail Shaft Fitted with Bronze Sleeve

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PLACING THE PROPELLER IN POSITION

The propeller is lowered into place by the shipriggers. Pads have been welded at suitablelocations on the ship shell to port and to starboard.As the crane man lowers the propeller to place,chair falls, hung from the pads, receive it and it isswung into place aft of the stern­frame eye and inline with the tail shaft. Roll the tail shaft until thekey in the taper is fair with the keyway in the hub.See Fig.306. The tail shaft is now pushed out andinto the hole in the propeller hub. The lock nut isnext installed and run onto within three inches ofthe after end of the hub. See Fig. 307.

FORCING THE PROPELLER ON THE TAILSHAFT

Theapprovedtypes ofwedgesand boxesare theninstalledbetween the lock nut and propeller hub for thepurpose of forcing the propeller on to the taper of thetail shaft.

A turn of red lead is inserted into the space (about3/4" deep) between the tail­shaft shoulder and theeye diameter. See Fig. 307.

INSTALLINGA PROPELLER AND TAIL SHAFT

The nut is then run up against the after end of the hubby means of a heavy, special spanner wrench. A heavychain fall is anchored to the skeg and hooked on to theouter end of the spanner wrench. With a steady strainon the chain fall and with repeated blows of a 30­lb.sledge on the outer end of the spanner, the machinistsnugs home the lock nut against the after end of thesternframe eye. Check with the leader for his approval.

248

SECURING THE LOCK NUT

The chain fall, spanner wrench, and other equipment arenow removed and returned to the tool rooms. A speciallocking device is installed to prevent the propeller lock nutfrom loosening. See Fig. 308. A hole just large enough totake the pin "a" (Fig. 308) is drilled into the after end of thepropeller hub. The hole is located in a convenient notch inthe lock nut. See Fig. 309. Holes are drilled and tapped in

Fig. 309­­Tail Shaft Lock Nut

the lock nut to fit the holes in the locking device, Fig. 309.The pin shown in Fig. 308 is inserted in the drilled hole inthe propeller hub, and cap screws are used to fasten thedevice securely in the lock­nut notch.

Figs. 310 and 311­­Fairwater Installed Over Propeller Lock Nut

SEALING THE LOCK NUT

A fairwater is installed over the after end of the propeller hub for the purpose of sealing thelock nut and protecting it from seawater. See Fig. 311. After the fairwater is installed, it isfilled with tallow through the hole provided (b), and a pipe plug is screwed in securely. SeeFig. 311. A similar hole is provided in the propeller hub through which tallow is poured toseal the tail shaft against corrosion should possible leaks occur. See Fig. 310 at "c".

249

After the fairwater is bolted to the propeller hub, the counter­bored, bolthead openings, Fig.311 "d", are sealed over with cement which prevents the loss of the bolts and also protectsthe boltheads from corrosion by salt water.

The job of installing the propeller and tail shaft may be outlined as follows:

PROCEDURE

1. Lower the tail shaft into the engine room.

2. Pass the tail shaft aft until the outer end of the threaded portion is flush with the stern­tubelock nut.

3. Lower the propeller into place on chain falls, fair with the stern­tube bore.

4. Roll the tail shaft until the key in the taper is fair with the keyway in the propeller.

5. Push the tail shaft through the stern tube, and engage the tapered bore in the propeller hub.

6. Install the lock nut, and run it on to within 3" of the after end of the hub.

7. Draw the propeller hub on to the tail­shaft taper by means of wedges and boxes.

8. Insert a turn of red lead between the tail­shaft shoulder and after face of the propeller.

9. Turn the nut home by using the special spanner wrench, chain fall, and 30­1b. sledge.

10. Remove the chain falls and other equipment, and return them to the tool room.

Fig. 312­­Docking Plug Assembly

11. Install the lock nut and lock key.

12. Install the fairwater.

13. Fill the fairwater recess and the propeller­hub recess with tallow. Insert pipe plugs andmake tight.

14. Cement fairwater bolthead openings.

250

Launching a Tanker

GENERAL INFORMATION

The outside machinist has several important jobs to perform before a ship can be launched.Docking plugs must be screwed in place; the ship's rudder must be securely locked in acentral, fore­and­aft position and the propeller must be firmly held so that it cannot turn whenthe ship slides into the water. In the bottom of a tanker there are forty­seven docking plugs.See Fig. 312.

Metal flanges are threaded to fit the plugs shown inFig. 312. The flanges are welded in openings in theship's bottom.

PURPOSE OF DOCKING PLUGS

The openings are located in the bottom so thatevery tank in the ship may be drained through them.A docking plug is screwed into the threaded hole inthe flange before the ship is launched.

While the ship is on the ways and before thedocking plugs area finally screwed in place, lengthsof pipe equipped with valves, are temporarilyscrewed in place and the valves are closed. Thetanks are filled with water to test them for leaks.When the tanks have been tested and approved thevalves in the pipe lengths are opened and the wateris drained. The docking Plug is then screwed inplace by means of a wrench which fits the squarehole in the plug. See Fig. 312. When a ship isplaced in drydock the docking plugs are removed toallow all the water or other liquid in the tanks andbilge to drain. Oil tankers are washed out with livesteam and the accumulation of water and oil isdrained out through the docking plug openings.

LOCKING THE RUDDER

When the ship slides down the ways, See Fig. 313, there are several thousand tons of, deadweight to control after the ship is in the water. The rudder must be securely locked so that itcan not be slammed around by the water pressure as the ship leaves the ways. There are twoways by means of which this is accomplished:

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1. SECURING RUDDER WHEN THE RUDDER STOCK IS INSTALLED

The riggers install cables at the stern of the ship. The cables are fastened from the rudder,port and starboard, to pads which are welded to the ship shell, port and starboard. The cablesare drawn up taut and made fast.

Fig. 314­­Chain Falls Attached

Tiller Jaws

Fig. 313­­The Ship Sliding Down the Ways

On the inside of the ship, Fig. 314, chain falls are fastened to the tiller jaws; one chain fall toport and one chain fall to starboard. The other end of each chain fall is fastened to the ship'sframe, port and starboard. The braces take the strain as the pull of the chain falls is exerted onthe tiller jaws. With the braces in place the chain falls are pulled up tight and locked, thusadding extra force inside the ship to assist the force of the cables installed outside of the shipby the riggers.

252

2. SECURING RUDDER WHEN THE RUDDERSTOCK IS NOT INSTALLED

Rudder stops are provided at the stern to prevent therudder from swinging more than 37 1/2 degrees toeither port or starboard. See Fig. 315.

When the rudder is in a central fore and aft positionthere is a space about 7 inches wide between therudder stops and the rudder bumpers. The riggersinstall cables at the stern of the ship as before. Withthe rudder held exactly fore and aft, R" to 1" thickplates about 7" wide are temporarily welded in thespace left between the rudder stops and the rudderbumpers. See Fig. 315. Whichever method is used,the work is supervised and Checked by the outsidemachinist.

HOLDING THE PROPELLER STATIONARY

The rush of water against the propeller as theship slides down the ways is sufficient to startthe propeller revolving. This must never beallowed to happen. Means must be provided tohold the propeller shaft and thus hold thepropeller. Fig. 316 shows a pair of heavy bars ofsteel which fit around the coupling flanges ofthe line shaft in the shaft alley. It will be notedthat the semi­circular cut­out in the center ofeach bar is for the purpose of allowing the barsto reach around the line shaft far enough for thebolts in the coupling flanges to pass through thebars.

Fig. 315­­Steel Plates are Welded to

Rudder and Rudder Stops

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Fig. 316­­Heavy Bars and Struts to Keep the Line Shaft From Turning

After the bars are bolted in place the lower ends of the bars are temporarily welded to thedeck and the upper ends are braced by struts welded to the port and starboard sides of theship shell.

When the ship is about ready for launching the docking plugs are all screwed in andinspected under the supervision of the outside machinist. Leaving a plug out or neglecting toscrew a plug in would be equivalent to drilling holes in the ship's bottom. Every docking plugmust be snugged home securely to prevent any possible leakage.

QUESTIONS

1. What is the purpose of a docking plug?

2. How is a docking plug flange installed in a ship?

3. Where are docking plugs located?

4. Why are docking plugs inspected carefully before the ship is launched?

5. Why must the ship's rudder be securely blocked in place before the ship is launched?

6. Describe the blocking operation as it is carried through when the rudder is installed.

7. Describe the blocking operation as it is carried through when the rudder stock is notinstalled.

8. Why must the ship's propeller be prevented from turning when the ship is launched?

9. Describe the method employed to lock the propeller in position while the ship is beinglaunched.

10. Make a list of the accidents and happenings that might take place if any of the duties ofthe outside machinist, as outlined in this lesson, were left undone.

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