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Doc. ID / Version: XXXXXX / A

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DOC. TYPE: Standard Operating Procedure

Program:

TEST

Project:

Materials Handling

Glass Block Handling for Processing

DOCUMENT CHANGE & HISTORY RECORD

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UpdateStatus Version Comment

Paul F. Geer 3-Aug-2008 CO A Initial release.

Applicable Documents

Ref. Title Doc. Id[1.1]

[1.2]

Tooling Required

Description Part Number

ONE 6 – INCH VACUUM CUP

TWO 3 X 6 – INCH VACUUM HAND GRIPS

ONE 35 LB WEIGHT BALANCER

LIFTING CHAINS

For change control: Reviewers: Approved by: For info:Paul F. Geer

Author: Paul F. GeersalklPages Incl. cover : 12

© LOGOS 2008. All rights reserved.Reproduction in whole or in part is prohibited without the prior written consent of LOGOS.

Standard Operating Procedure Doc ID / Version: XXXXXX / A

TABLE OF CONTENTS

1 GENERAL..............................................................................................................................3

1.1 PURPOSE.......................................................................................................................3

1.2 SCOPE............................................................................................................................3

2 RESPONSIBILITIES...............................................................................................................4

2.1 TECHNICIAN...................................................................................................................4

2.2 MANAGEMENT...............................................................................................................4

3 PROCESS DEFINITION.........................................................................................................5

3.1 EQUIPMENT....................................................................................................................5

3.2 PROCESS OVERVIEW...................................................................................................7

4 HANDLING LARGE BLOCKS FOR LAP PROCESSING.....................................................8

4.1 SETUP PROCESS..........................................................................................................8

4.2 REMOVAL PROCESS...................................................................................................10

Appendix A procedure checklist..........................................................................................13

LIST OF FIGURESFigure 3.1 Articulated Jib Crane: Example..............................................................................................5Figure 3.2 Jib Crane Setup for a Continuous Polisher Workstation........................................................6Figure 3.3 Six – Inch Vacuum Cup.........................................................................................................6Figure 3.4 3 X 6 – Inch Vacuum Hand – Grip.........................................................................................7Figure 4.1 The Weight Balancer and 6” Vacuum Cup Assembly............................................................8Figure 4.2 6” Vacuum Cup Attached to Work piece................................................................................9Figure 4.3 Hand Grips Attached to Workpiece......................................................................................10Figure 4.4 Arrangement for Lifting the Carrier Ring..............................................................................11

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1 GENERAL

1.1 PURPOSE

1.1.1 The Continuous Polishing Department frequently processes workpieces of more than 30 lbs in weight. Such workpieces create difficulties in meeting tight production schedules, because of the physical limitations of those involved with moving and processing materials. Without special tooling, serious injuries may result through dropping materials from mishandling. The department resolves this problem through equipping workstations with articulated jib cranes, in which weight balancers are attached to the hoists for load reduction.

1.1.2 When a trained technician sets up a jib crane for handling, he or she first attaches the workpiece to the weight balancer suspended from the hoist, and then attaches gripping tools on the workpiece’s surface for maneuvering the load (see Chapter 3). In applying this arrangement, the balancer’s upward pull deminishes the workpiece’s effective weight by 80%.

1.1.3 The jib cranes accomplish the following results for the technician in Continuous Polishing:

1) They facilitate ease of movement and positioning at department workstations.

2) They enhance safety, and prevent injuries caused by handling excessive weight.

3) They protect materials from damage or total loss due to accidents.

4) They help to preserve quality of end products fabricated from the materials.

1.1.4 This document outlines the most effective means, and tools necessary, for consistently obtaining the above results in handling.

1.2 SCOPE

1.2.1 The procedure discussed below shall mainly apply to materials having a rectangular form, e.g., blocks having six (6) flat faces. The blocks should have at least two mutually parallel blanched or ground faces, as is typical of many flat optics processed in the department.

1.2.2 The TEST Glass Blocks, which weigh approximately 40 pounds apiece, are the primary examples of optics included within this document’s scope.

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2 RESPONSIBILITIES

2.1 TECHNICIAN

2.1.1 This procedure requires that technicians observe the following precautions:

1) They must ensure that the environment does not disturb the vacuum cups shown in Figure 3.3, in the next chapter. In particular, they must not allow anything to disturb plungers or release tabs, as this can break the suction.

2) They must also ensure the vacuum cups are clean prior to use; any contaminants on the rubber pads can also disrupt suction, since the pads directly contact the materials being handled. Further, whenever cleaning is necessary, they are to use WATER ONLY; the use of other cleaning solvents, such as Methanol, can degrade and weaken the rubber.

3) Besides making sure vacuum cups are clean, technicians must also ensure optical surfaces of materials are free of contaminants. A dirty surface can interfere with the contact of the vacuum cup, disrupting the suction.

4) A vacuum cup is not to be used if the rubber pad appears damaged or worn, or if the cup otherwise fails to hold onto surfaces after attachment.

5) When operating a jib crane, technicians must NEVER attempt lifting materials exceeding the crane’s load capacity. Most cranes in Continuous Polishing are capable of lifting up to 240 lbs maximum.

WARNING: Not following the above precautions significantly increases the risk of optics detaching from the vacuum cups.

2.1.2 Whenever a problem arises with the jib crane, or the associated equipment, the technician is responsible for notifying the supervisor or responsible engineer. The technician is not to perform any handling operations with defective equipment, until qualified specialists complete the necessary repairs.

2.1.3 The technician must fill a checklist, to certify that he or she has completed the required steps of the procedure. The form for this checklist can be found in Appendix A of this document.

2.2 MANAGEMENT

2.2.1 The area supervisor or manager must ensure all equipment at CP workstations is in working order, and is safe for use. This includes ensuring the availability of spare parts for cranes, vacuum cups, etc., through regular contact with suppliers.

2.2.2 The management must ensure that technicians carefully observe all work instructions as stated in this document. He or she must regularly review checklists submitted for processing jobs, to ensure the procedure has been completed as instructed herein.

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3 PROCESS DEFINITION

3.1 EQUIPMENT

3.1.1 Continuous Polishing operates jib cranes similar to those manufactured by the American Industrial Manipulator Company (a.k.a. AIMCO). Figure 3.1 provides a photographic view of one example.

Figure 3.1 Articulated Jib Crane: Example

3.1.2 In a typical crane a weight balancer, which is essentially a drum containing a recoiling hook line, is mounted to a hoist at the end of a swiveling arm assembly with two rotating members. The arm assembly, in turn, carries the attached balancer in rotation about the top of a pedestal. The crane is generally placed next to a CP machine, to enable the hook line to raise materials from, and lower materials onto, the lapping plate of the CP.

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3.1.3 In Figure 3.2, an illustration shows the basic layout of a CP workstation, which includes a drawing of a crane for lifting and moving heavy flat optics, such as the TEST Glass Blocks. The elements illustrated are somewhat approximate in scale.

1

2

5

4

3

7

6 8

CP WORKSTATION COMPONENTS (AS NUMBERED ABOVE)

1. CRANE PEDESTAL 6. BLANCHARD / GRINDING MACHINE2. SWIVELING ARM ASSEMBLY 7. CARRIER RING3. HOIST 8. TRANSPORTER CART4. WEIGHT BALANCER 9. STYROFOAM CUSHION5. VACUUM CUP 10. BLOCK (WORKPIECE)

Figure 3.2 Jib Crane Setup for a Continuous Polisher Workstation

3.1.4 Component No. 5, the vacuum cup, is the critical element needed for attaching handled material to the jib crane. Figure 3.3 provides a diagram of a 6-inch vacuum cup, a tool commonly used with workstation cranes:

PLUNGER

RELEASE TABS

VACUUM PAD

FLIP HANDLE

Figure 3.3 Six – Inch Vacuum Cup

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3.1.5 Two other vacuum cups (not shown in Figure 3.2) are used for the physical maneuvering of material between the CP machine (No. 6) and the transporter cart (No. 8). These cups function as hand-grips, and are directly mounted onto the material, after the above 6-inch vacuum cup. Figure 3.4 provides a diagram.

PLUNGER

RELEASE TABS

VACUUM PAD

HANDLE

Figure 3.4 3 X 6 – Inch Vacuum Hand – Grip

3.2 PROCESS OVERVIEW

3.2.1 Chapter 4 describes the method of handling flat optics with the above equipment. This description covers both the setup and removal processes.

3.2.2 In the CP Department, each jib crane used is generally capable of extending across the lapping plate’s diameter. This enables technicians to raise or lower materials at any point on the plate’s surface, as needed. However, for safety, the technician mostly performs the material handling as close as possible to his or her standing position, near the workstation.

3.2.3 In the usual application of a crane, the technician transfers a heavy work piece from a transporter cart to the lapping plate of a CP machine, for setup. After processing, the technician uses the crane to return the work piece to the Styrofoam cushion, on the cart. After the work piece is covered with a Plexiglas shield, the cart is then moved to another production area.

3.2.4 The setup and removal procedures both use the same tooling discussed in Section 3.1.

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4 HANDLING LARGE BLOCKS FOR LAP PROCESSING

4.1 SETUP PROCESS

4.1.1 Attach the 35 lb weight balancer to the hoist, and then attach the 6-inch vacuum cup to the balancer, by inserting the flip handle into the hook. Figure 4.1 provides an illustration. Make sure the hook latches of the hoist and weight balancer are properly secured.

Figure 4.5 The Weight Balancer and 6” Vacuum Cup Assembly

4.1.2 Wheel the transporter cart, and the block, to a position near the CP machine. The block should be on a Styrofoam cushion and enclosed under a Plexiglas cover. Remove the Plexiglas cover to expose the block.

4.1.3 Clean the top surface of the block, to provide a dust – free surface for attaching the vacuum cup. Clean with tissue paper (optical grade) moistened with a solvent that will not degrade the glass. The vacuum pad of the cup also may be wiped with tissue and water, as needed.

WARNING: AS INDICATED IN SECTION 2.1, EITHER A DIRTY VACUUM CUP OR A DIRTY OPTICAL SURFACE CREATES A POTENTIAL FOR DROPPING.

4.1.4 Attach the 6-inch vacuum cup to the block’s top surface. Pressing the plunger creates suction for holding the cup to the block. (The plunger is essentially a small pump.) Place the cup so it is centered on the surface, as shown in Figure 4.2. Note: Pulling down the hook line of the balancer requires effort because of the recoil.

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WARNING: MAKE SURE THE VACUUM CUP REMAINS COMPLETELY ATTACHED TO THE SURFACE. DO NOT USE THE CUP IF IT FAILS TO MAINTAIN SUCTION. See Section 2.1.

Figure 4.6 6” Vacuum Cup Attached to Work piece

4.1.5 Attach two hand grips to the block’s top surface, operating the plungers as when attaching the 6” cup. (The hand grips have a 3 X 6-inch oval pad.) Position the hand grips next to the block’s shorter edges. The grips should also be parallel to the edges, with the 6-inch vacuum cup between them, as in Figure 4.3.

WARNING: MAKE SURE THE GRIPS REMAIN COMPLETELY ATTACHED TO THE SURFACE. DO NOT USE THEM IF THEY FAIL TO MAINTAIN SUCTION. See Section 2.1.

Figure 4.7 Hand Grips Attached to Work piece

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4.1.6 Stop the lapping plate’s rotation, by toggling the appropriate switch on the CP control panel. The loading process must be done while the lapping plate is motionless.

4.1.7 Using the hand grips, and relying on the load lessening effect of the weight balancer, lift the block from the transporter cart and then lower it into the carrier ring, on the CP lapping plate.

4.1.8 When the block is safely in position, remove the 6-inch vacuum cup and two hand grips from the top surface. To loosen each of these from the surface, pull one of the release tabs on the vacuum pad to break the suction. (Pulling a tab enables air to get inside the pad.)

4.1.9 Unhook the 6-inch vacuum cup from the weight balancer, and move the jib crane’s extension arm clear of the CP machine. Then unhook the weight balancer from the hoist.

Note: THE BLOCK IS NOW READY FOR PROCESSING WITH THE CP.

4.1.10 Place on the block the load required for an effective polish. Use weights that are safe for direct contact with the glass. After loading the block, switch on the CP through operating the CP’s power control, to launch processing.

4.2 REMOVAL PROCESS

4.2.1 Stop the rotation of the polishing lap: switch off the CP through operating the machine’s power control. Remove the weights used for loading the block.

4.2.2 Prepare to raise the carrier ring off the lap, for removing the block: attach one end of the lifting chains to the hoist; and then connect the chains’ remaining ends to the carrier ring, by hooking them to the three (3) eyelets on the top edge. See Figure 4.4.

Figure 4.8 Arrangement for Lifting the Carrier Ring

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WARNING: STEPS 4.2.3 AND 4.2.4 REQUIRE TWO TECHNICIANS TO COMPLETE.

4.2.3 Get into position for raising the carrier ring.

Technician No. 1. Stand in position for hoisting the carrier ring off the lap.

Technician No. 2. Stand next to the carrier ring holding the block. Be ready to guide the ring when Technician No. 1 starts the hoist.

4.2.4 Raise the carrier ring approximately 12 inches.

Technician No. 1. Pull down the hoist chain to raise the carrier ring. Do this until the carrier ring is at the desired height.

Technician No. 2. While Technician No. 1 raises the ring, hold the ring to prevent it from hitting the block. If allowed to swing too freely, the ring might contact the block and cause damage.

4.2.5 Slide the block on the lapping plate’s surface, until partially over the plate’s edge. For safety, do not have the block extend by more than ½ its length beyond the edge. Position the block so its longer edges aim towards the center of the plate.

WARNING: BEFORE LOWERING THE CARRIER RING, MAKE SURE THE BLOCK IS CLEAR OF THE RING’S LOCATION ON THE LAPPING PLATE. If this precaution is not carefully observed, the ring will have a greater risk of contacting the block, resulting in damage to the ring and/or the block.

4.2.6 After positioning the block according to Step 4.2.5, lower the carrier ring back onto the lapping plate, at its normal location for processing operations. Unhook the lifting chains from the ring and the hoist.

4.2.7 Attach the 35 lb weight balancer to the hoist. Then attach the 6-inch vacuum cup to the balancer, inserting the cup’s flip handle into the hook. (Refer to Figure 4.1.)

4.2.8 Clean the top surface of the block, to provide a dust – free surface for attaching the vacuum cup. Wipe the vacuum pad of the 6-inch cup, if needed. Observe the WARNING of Step 4.1.3.

4.2.9 Attach the 6-inch vacuum cup to the block’s top surface, pressing the plunger to create suction. (See Figure 4.2 for positioning on the surface.) Observe the WARNING of Step 4.1.4.

4.2.10 Attach two hand grips to the block’s top surface, operating the plunger of each to create the suction. (See Figure 4.3 for positioning on the surface.) Observe the WARNING of Step 4.1.5.

4.2.11 Using the hand grips, lift the block off the lapping plate and transfer it to the Styrofoam pad, on the transporter cart. Make sure the block is properly seated in the pad’s indentation.

4.2.12 After safely removing the block from the CP, remove the 6-inch vacuum cup and two hand grips from the block’s top surface. Pull on the release tabs for loosening.

4.2.13 Place the Plexiglas cover over the block, to safeguard the block against dust.

4.2.14 Switch on the CP through operating the appropriate power control, to continue processing the remaining materials on the lapping plate.

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APPENDIX A PROCEDURE CHECKLIST

LOADING BLOCK INTO CONTINUOUS POLISHER

DO EACH STEP BELOW BEFORE POLISHING. Check corresponding box to show completion:

1. Two technicians available for operation.

2. 6-inch vacuum cup and 35 lb weight balancer attached to hoist.

3. Surface of block cleaned.

4. 6-inch vacuum cup attached to center of block surface.

5. Two oval vacuum cups attached close to block short side.

6. CP stopped.

7. Block moved into CP lap carrier, directed with oval vacuum handles.

8. Vacuum cups and weight balancer removed from block.

9. Weight placed on block.

10. CP restarted for processing.

11. 6-inch vacuum cup and weight balancer removed from hoist.

Name: Date:

REMOVING BLOCK FROM CONTINUOUS POLISHER

DO EACH STEP BELOW AFTER POLISHING. Check corresponding box to show completion:

1. CP stopped.

2. Weight on block surface removed.

3. Lifting chains hooked to polishing ring and hoist.

4. Technician No. 1 in position for lifting polishing ring.

5. Technician No. 2 in position for guiding polishing ring.

6. Polishing ring lifted approx. 12 inches while guided by Technician No. 2.

7. Block moved to edge of polishing lap, for access.

8. Polishing ring lowered to operating position.

9. Lifting chains removed.

10. 6-inch vacuum cup attached to 35 lb weight balancer, on hoist.

11. Surface of block cleaned.

12. 6-inch vacuum cup attached to center of block surface.

13. Two oval vacuum cups attached close to block short side.

14. Block lifted from CP lap carrier and into cart, directed with oval vacuum handles.

15. CP restarted for processing.

Name: Date:

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