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Dry docking inspection

- The period when a ships in dry-dock is that time in a ships life thataccess the underwater volume allow a thorough inspection

- It is clearly an opportunity to carry out a detailed inspection of the under

part of the ship

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A surveyor would have to pay particular attention to certain items inessential area

- A good place to start a dry-dock inspection is at the head of the dry-dock,

working down the portside and up the starboard side

Anchor and anchor chain cable

- Anchor head, flukes and shanks should be surface examined for cracks

- If any such defects are found they may be weld-able, otherwise renewal

will probably be necessary

- In such cases welding may be attempted as a temporary measure pending

availability of the new equipment, which may take 3 to 6 months-

Anchor head crown pins and anchor shackle pins should be hammered

tested, hardened up if slack, or renewed if excessively worn or bent

- Swivels if fitted should be closely examined so far as possible in way of

the threaded connection, as many have been lost in service due to

concealed wastage in this area

- If in doubt the swivel should be recommended to be removed

- Consideration should be given to simply eliminating any questionable

swivels, they are normally not essential

- Anchor chain cable should be surface examined, hammer tested and loose

or missing studs replaced by welding at one end of the stud only, at the

end of the stud opposite the link butt weld- The rest of the chain cable should be further examined for excessive wear

and gauges of necessary to ensure continued compliance with the rules

- Verify that the number of shots of anchor fitted port and starboard both

equal to the total length required by classification rule equipment

numerical

Hull plating

- The first few plats in the keel, A and B strakes call for particularattention as they are vulnerable to pounding damage and also to erosion

and corrosion of welded or riveted connections, particularly where

chafed by the anchor chains

- Eroded or corroded butts and seams should be cleaned or back chipped to

sound metal and re-welded

- A minimum reinforcing is desirable on these welds to prevent entrapped

air from the bow wave attacking the weld again

- The re-welded joints should be cleaned of all slag and carefully primed

and coated

- Corrode or slightly leaking rivets may be caulked or ring welded of

condition is not widespread and the rivets are not loose

- The underwater bottom should be sighted frequently as the inspection

progresses towards the stern for hogging, sagging, grounding damage, ordistortion possibly indicative of structural weakness

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- The bottom and side-shell plating in the mid-ship area, particular below

and in line with deckhouse or hatch ends, calls for close examination for

possible presence of transverse deformation between frames

- It is important to look carefully for signs of deformation possibly

attributable to structural weakness, wastage, as differentiated from

ground or striking indents

Bilge keel

- Directly attached bilge keels or bilge keels landing bars should be

examined for fractures or corrosion grooving of the shell plating in way of

any discontinuities of their attachment

- Fractured butt welds in the bilge keel should be chipped to sound metal

and re-welded and any slack riveted renewed

- It is of particular interest to see that fracture in the bilge keel do not

propagates into the hull, and that no notches or hard spots are left

which might lead to cracking of bilge strake

Overboard fitting

- Overboard discharge pipes, their shell reinforcement rings and external

shell plating beneath the outlets should be checked for excessive

corrosion

- This is particularly applicable to evaporator drain, boiler blow down, and

inert gas scrubber discharges

- Sea chests should be examined for fractures particularly in way of the

corners, for aerated water corrosion, and the condition of the strainers

and their securing devices

Dry dock safety

- Daily morning safety meeting with shipyard safety officer, repair

manager, foreman, ships senior officer and in-charge superintendent

- Establish, and adopt a work permit system

- Avoid unnecessary fuel oil and diesel oil tank to tank transfer

- Avoid using fuel oil for pipe pressure testing

- Avoid hot work near fuel sources

- Unless permitted, avoid tanks chemical washing

- Unless permitted, avoid spray painting

- Do not do ballast and de-ballasting while in the dry dock

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Avoid using the ship crane while in dry dock

- Avoid turning the main engine rudder and propeller while in dry dock

- Always keep fire protection equipment and system in a ready to use state

- Ensure all fire protection and warning system are operational

- All emergency exit are clearly marked and clear of obstruction