Steering Clutch and Brake Discs and Plates for Scrapers, Pipelayers, Track-Type Tractors, and Loaders {4100, 4255} Caterpillar

Pipelayer

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Track-Type Loader

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Track-Type Skidder

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Track-Type Tractor

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Wheel Tractor-Scraper

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Introduction

© 2018 Caterpillar All Rights Reserved. This guideline is for the use of Cat dealers only. Unauthorized use of this document or the proprietary processes therein without permission may be violation of intellectual property law.

Information contained in this document is considered Caterpillar: Confidential Yellow.

This Reuse and Salvage Guideline contains the necessary information to allow a dealer to establish a parts reusability program. Reuse and salvage information enables Caterpillar dealers and customers to benefit from cost reductions. Every effort has been made to provide the most current information that is known to Caterpillar. Continuing improvement and advancement of product design might have caused changes to your product which are not included in this publication. This Reuse and Salvage Guideline must be used with the latest technical information that is available from Caterpillar.

For technical questions when using this document, work with your Dealer Technical Communicator (TC).

To report suspected errors, inaccuracies, or suggestions regarding the document, submit a form for feedback in the Service Information System (SIS Web) interface.

Canceled Part Numbers and Replaced Part Numbers

This document may include canceled part numbers and replaced part numbers. Use NPR on SIS for information about canceled part numbers and replaced part numbers. NPR will provide the current part numbers for replaced parts.

Important Safety Information

Illustration 1	g02139237

Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools to perform these functions properly. Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. If a tool, a procedure, a work method, or operating technique that is not recommended by Caterpillar is used, ensure that it is safe for you and for other people to use. Ensure that the product will not be damaged or the product will not be made unsafe by the operation, lubrication, maintenance, or the repair procedures that are used.

Show/hide table

Improper operation, lubrication, maintenance or repair of this product can be dangerous and could result in injury or death. Do not operate or perform any lubrication, maintenance or repair on this product, until you have read and understood the operation, lubrication, maintenance and repair information.

Safety precautions and warnings are provided in this manual and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons.

The hazards are identified by the safety alert symbol which is followed by a signal word such as danger, warning, or caution. The “WARNING” safety alert symbol is shown below.

Illustration 2	g00008666

This safety alert symbol means:

Pay attention!

Become alert!

Your safety is involved.

The message that appears under the safety alert symbol explains the hazard.

Operations that may cause product damage are identified by "NOTICE" labels on the product and in this publication.

Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. The safety information in this document and the safety information on the machine are not all inclusive. Determine that the tools, procedures, work methods, and operating techniques are safe. Determine that the operation, lubrication, maintenance, and repair procedures will not damage the machine. Also, determine that the operation, lubrication, maintenance, and repair procedures will not make the machine unsafe.

The information, the specifications, and the illustrations that exist in this guideline are based on information which was available at the time of publication. The specifications, torques, pressures, measurements, adjustments, illustrations, and other items can change at any time. These changes can affect the service that is given to the product. Obtain the complete, most current information before you start any job. Caterpillar dealers can supply the most current information.

Summary

New components are not often necessary for the reconditioning of steering clutches and brakes. The installation of reconditioned components can result in large cost reductions. This document was developed to provide a visual guide for the reusing of steering clutches and brake discs.

Never install a part that is not to be used again by this Guideline. The discs can be used again without reconditioning if none of the following damage exists:

• Scratches

• Discoloration

• Warp

• Dish

Procedures to recondition scratched faces of reaction, or lightly pitted faces of reaction are given in this Guideline. Minimum thicknesses, and specifications for the maximum amount of warp and dish are also given. Do not use any other method of cleaning or reconditioning including the following methods:

• Machining with a lathe

• Clean with grit, glass beads, or shot

• Clean with a pad for reconditioning including 8T-7765 Surface Reconditioning Pad

Any method that changes the finish of the faces of reaction can cause rapid wear of the friction material or excessive slipping of the clutch and/or slipping of the brake.

During reconditioning, correct any conditions that may have caused the original failure.

Glossary

Circumferential - Circular in shape

Discoloration - Change in color

Dish - Bent in the radial direction

Erosion - The condition that includes deterioration or breakage of the friction material on the land edges of friction discs

Flatness - The degree of change between a surface and a single plane

Glazed - The condition that includes the development of a smooth layer on the friction material that is similar in appearance to glass

Groove Pattern - Design of grooves cut into the surface of the friction material

Polished - Having a shiny surface

Radial - on a line from the center to the outside of a circle

Pit - The indentation in a surface formed by rust, erosion, fatigue, foreign material, and so forth.

Warp - Twisted out of shape

Maximum Permissible Wear - The greatest acceptable wear before the part needs replacing. If the part is worn to this dimension, the part cannot be used again.

Use Again Maximum - is the greatest acceptable wear on a part that will be installed again. If wear exceeds the Use Again Maximum, do not reuse the part.

Plates

This section discusses equipment with steering clutches that are cooled by oil and brake discs.

Discolored Reaction Faces and Smeared Reaction Faces

Clutch plates and brake plates will show light or heavy smearing on the reaction faces. Brake plates will have bronze colored streaks when the brake plates are mated to bronze friction discs. These streaks are bronze from the friction material on the disc assemblies. These plates can be used again after reconditioning.

Clutch plates that are lightly smeared with narrow circumferential lines can be used again after reconditioning. When the slippage becomes excessive, friction causes more heat in the clutch plates and disc assemblies. This heat will discolor the clutch plates and the heat will damage the faces of reaction. Heat can also cause the plates and/or discs to warp. Plates can be reused after reconditioning if discoloration is light brown. Do not reuse plates with blue or black discoloration.

Illustration 3	g01597974
This part is in like-new condition. No signs of smearing or discoloration.

USE THIS PART AGAIN.

Illustration 4	g01597995
Light smearing.

USE THIS PART AGAIN.

Use this part again after reconditioning.

Illustration 5	g01598015
Light discoloration.

USE THIS PART AGAIN.

Use this part again after reconditioning.

Illustration 6	g01610274
Heavy smearing and black discoloration.

DO NOT USE THIS PART AGAIN.

Illustration 7	g01610293
Blue or black discoloration.

DO NOT USE THIS PART AGAIN.

Illustration 8	g01610318
Crack originating from the fillet of a tooth with excessive discoloration on a plate.

DO NOT USE THIS PART AGAIN.

Reconditioning Procedure for Plates

Illustration 9	g01610354
Use emery cloth that is 80 grit that is wetted with solvent to remove the glaze from a high spot. Use the cloth in the direction in the illustration.

Remove glaze and grind marks by sanding with wet emery cloth of 80 grit on a block. Sanding should be done in the radial direction. Clean using a brush and solvent after glaze is removed.

Note: This procedure is used for plates that require a surface finish from 0.5 µ meter (19.68 inch) to 1.6 µ meter (62.99 microinch). Refer to Table 2. Abrasive material is not to be used in the circular direction on a plate with a high spot.

The reconditioned surface must be rough enough to wear the corner of a copper coin. Do not use power sanders or an abrasive cleaning pad to remove the glaze from a plate.

Drive Tangs or Teeth

Do not reuse plates with more than 0.8 mm (0.03 inch) wear on either side of all the tangs. Do not reuse plates with more than 0.4 mm (0.02 inch) maximum wear on the spline teeth. If all the teeth or tangs have not worn to that point, the plate can be reused. Uneven wear indicates that all the driving surfaces are not fully sharing the load. However, uneven wear does not indicate a faulty part or a worn out part. If there are shiny spots or dark spots on the disc, check for variation in thickness, a maximum of 0.03 mm (0.001 inch) for bronze and 0.051 mm (0.0020 inch) for paper and graphite.

Illustration 10	g01610393

USE THIS PART AGAIN.

Use this part again if the wear steps on either side of all tangs do not exceed a maximum of 0.8 mm (0.03 inch) or 0.4 mm (0.02 inch) on the spline teeth.

Surface Texture

Surface textures vary as different types of discs are used with different plates. Refer to Table 2.

Note: To test a surface finish for minimum roughness and grinding patterns on plates with a 1.6 µm (62.99 µinch) specification, rub the edge of a copper coin around the circumference of the face of reaction. The surface has the correct pattern and minimum roughness if the coin shows abrasion.

Illustration 11	g01610433

USE THIS PART AGAIN.

Use this part again if there is not excessive warpage or dish, and if the surface texture is correct. The clutch plate shows circumferential marks but no grooves.

Measurement of Warp and Dish

1. Remove any rough edges in the area of the slot for the pin.

2. Put the clutch plate on a flat surface. Such as the face of reaction of a clutch housing, center plate of a transmission, or a surface plate. If dish is obvious, put the plate on the flat surface so the concave side is up.

3. Measure the gap between the clutch plate and the face of inspection at both the outside diameter (OD) and the inside diameter (ID). Take measurements at a minimum of three points around the plate with equal distances between the points.

4. If gap (A) at the outside diameter at any of the points is more than 0.38 mm (0.015 inch), the clutch plate cannot be used again.

5. If gap (B) at the inside diameter at any of the points is more than 0.15 mm (0.006 inch), the clutch plate cannot be used again.

6. If the gaps in step 4 and step 5 are acceptable, subtract the measurement of gap (B) from the measurement of gap (A). If the difference is more than 0.15 mm (0.006 inch), the clutch plate cannot be used again.

Example

The measurement of gap (A) is 0.28 mm (0.011 inch) which is less than the maximum. The measurement of gap (B) is 0.10 mm (0.004 inch) which is less than the maximum. This difference between the measurement of gap (A) and gap (B) is 0.18 mm (0.007 inch) which is more than the maximum. This clutch plate cannot be used again.

Illustration 12	g01610453
Measurements of Gap (A) and Gap (B)

Illustration 13	g01610533
Measurements of Gap (A) and Gap (B)

Plate Specifications

Oil Cooled Bronze Discs

Erosion

Do not use this part again if more than 10% of the total surface area has been affected.

Illustration 14	g01610555

USE THIS PART AGAIN.

Use this part again if less than 10% of the total surface area has been affected.

Illustration 15	g01610595

DO NOT USE THIS PART AGAIN.

Do not use this part again if more than 10% of the total surface area has been affected.

Illustration 16	g01610726

USE THIS PART AGAIN.

Use this part again after reconditioning.

Illustration 17	g01610733
Erosion covers more than 10% of surface.

DO NOT USE THIS PART AGAIN.

Illustration 18	g01610753
Streaks of erosion do not exceed 10% of the total surface area. Refer to"Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs" for additional information.

USE THIS PART AGAIN.

Use this part again after reconditioning.

Illustration 19	g01610793
Erosion does not exceed 10% of the total surface area. Refer to "Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs" for additional information.

USE THIS PART AGAIN.

Use this part again after reconditioning.

Illustration 20	g01610813
Streaks of erosion do not exceed 10% of the total surface area.

USE THIS PART AGAIN.

Illustration 21	g01611314
Approximately 10% of the total surface area has been lost by erosion.

DO NOT USE THIS PART AGAIN.

Illustration 22	g01611377
Streaks of erosion do not exceed 10% of the total surface area. Refer to "Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs" for additional information.

USE THIS PART AGAIN.

Use this part again after reconditioning.

Illustration 23	g01611395
Discoloration of the surface.

USE THIS PART AGAIN.

Use this part again after reconditioning and removing discoloration of the surface. Refer to "Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs"for additional information.

Damage from Foreign Material

Discs that have been damaged by foreign material can be reused if all the foreign material is removed from the face and if no more than 10% of the total surface area has been damaged.

Note: All forms of damages to the face (pitting, erosion, foreign material, etc.) must be considered when the percentage of damaged material is considered.

Illustration 24	g01611453
All the foreign material has been removed from the surface and the affected surface area is less than 10% of the total.

USE THIS PART AGAIN.

Tooth Wear

Do not reuse discs if the teeth have worn more than 25% of the original width. If the teeth have notches, do not use the disc again.

Glazed Surfaces

Use the"Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs" to remove the shiny skin from glazed discs.

Uneven Side-To-Side Wear on the Face

Do not reuse discs with uneven side-to-side wear on the face. One side should not be less than half of the other side.

Illustration 25	g01611475
This illustration shows uneven wear. The relationship between lining (C) and core (D).

Oil Cooled Nonmetallic Discs

Erosion or Outside Forces

Do not reuse discs if the teeth have worn more than 25% of the original width. If the teeth have notches, do not use the disc again.

Illustration 26	g01611481
Light wear.

USE THIS PART AGAIN.

Illustration 27	g01611488
Light wear.

USE THIS PART AGAIN.

Illustration 28	g01611553
Excessive chipping and erosion.

DO NOT USE THIS PART AGAIN.

Illustration 29	g01611575
Cracking at root of spline.

DO NOT USE THIS PART AGAIN.

Dry Metallic Discs

Tooth Wear

Illustration 30	g01611617
Wear on tips of teeth exceeds 25% of the original width.

DO NOT USE THIS PART AGAIN.

Illustration 31	g01611633
The illustration shows notches that are worn into the teeth of a friction disc. (E) Notch (F) Normal Tooth Surface

DO NOT USE THIS PART AGAIN.

Illustration 32	g01611653
The illustration shows wear in the teeth of a friction disc. (G) Shallow Wear (H) Normal Tooth Surface

USE THIS PART AGAIN.

Glazed Faces

Discs with glazed faces can be reused after reconditioning. Refer to "Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs" for additional information.

Uneven Side-To-Side Wear on the Face

Do not reuse discs with uneven side-to-side wear on the face. The friction material on one side should not be less than half the thickness of the other side.

Illustration 33	g01611674
Teeth have not worn more than 25% of the original width. Faces are lightly glazed.

USE THIS PART AGAIN.

Use this part again after reconditioning if specifications match the specifications in Table 3. To remove glazing, refer to "Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs"

Procedure for the Reconditioning of Dry Metallic Discs and Oil Cooled Metallic Discs

During normal operation, disc assemblies may become discolored and glazed. A discolored and glazed disc is the result of elevated temperature and lubricants. Clean disc assemblies thoroughly before reinstalling. Both faces of reaction of the disc assembly must be cleaned with emery cloth. A hand sander with emery cloth of 180 grit must be used to clean the disc assembly. Use the emery cloth in either a clockwise direction or counterclockwise direction to the diameter of the disc assembly.

Note: Do not use a power sander to clean the disc assembly. Do not use the emery cloth in a radial direction. Discs that are not correctly reconditioned will be damaged beyond reusability.

Confirm that the thickness agrees with the specifications in Table 3. After both faces of reaction are cleaned with emery cloth, the disc assembly must be washed in a petroleum-based solvent of a light caustic solution that will not harm the friction material of the disc assembly. If the disc assemblies are not washed, abrasive material can cause rapid wear.

Illustration 34	g01611754

Dry Fiber Discs and Mating Plates

Do not reuse discs that have been in contact with oil. If a disc is worn more than the specifications in Table 3, do not use the disc again. Do not use discs if more than seven teeth have been damaged.

Illustration 35	g01611794
Normal appearance

USE THIS PART AGAIN.

Illustration 36	g01611813
Rust from the plates has been deposited on the face. Only the three teeth that are shown by the arrow are damaged. This disc could be used again if only the condition of the teeth is considered.

DO NOT USE THIS PART AGAIN.

Illustration 37	g01611914
This disc has been soaked in oil.

DO NOT USE THIS PART AGAIN.

Plates

Pitting

Plates mated with the molded clutch discs of fiber that are used in the D3 Tractors and 931 Loaders commonly have some pitting. Refer to Illustrations 38 and 39. Plates mated to bronze or cellulose discs should not be pitted.

Illustration 38	g01611934
Normal pitting for D3, D3B, D3C, 931, 931B and 931C only.

USE THIS PART AGAIN.

Illustration 39	g01611957
Maximum normal pitting for D3, D3B, D3C, 931, 931B and 931C only.

USE THIS PART AGAIN.