- Agricultural Tractor
- Armored Face Conveyor
- Articulated Truck
- Asphalt Paver
- Backhoe Loader
- Beamed Stageloader
- Cold Planer
- Compact Track Loader
- Compact Wheel Loader
- Continuous Haulage
- Continuous Miner
- Earthmoving Compactor
- Electric Rope Shovel
- Face Haulage
- Feeder Breaker
- Forest Products
- Hydraulic Shovel
- Integrated Toolcarrier
- Landfill Compactor
- Load Haul Dump
- Expanded Mining
- Material Handler
- Mini Hydraulic Excavator
- Motor Grader
- Multi Terrain Loader
- Off-Highway Truck/Tractor
- Paving Compactor
- Pneumatic Compactor
- CW12 (S/N: RHJ1-UP)
- CW34 (S/N: 3G41-UP)
- Pumper All
- Utility Mounted
- Road Reclaimer/Soil Stabilizer
- Roof Bolter
- Roof Support Carrier
- Roof Support
- Rotary Drill
- Skid Steer Loader
- Soil Compactor
- Track Drills
- Track Feller Buncher
- Track-Type Loader
- Track-Type Skidder
- Track-Type Tractor
- Underground Articulated Truck
- Unit Rig Mining Truck
- Vibratory Soil Compactor
- Wheel Dozer
- Wheel Feller Buncher
- Wheel Loader
- Wheel Skidder
- Wheel Tractor-Scraper
- Wheeled Excavator
|Revision||Summary of Changes in SEBF8728|
|19||Added "Nut Inspection" and "Washer Inspection" Sections. Updated definitions and added Illustration 3.
Updated Tables 2 and 3, Illustrations 1 and 2. Updated effectivity and boilerplate information.
|18||Added more prefixes for NPI.|
|17||Added new serial number prefixes for New Product Introduction (NPI).
Updated copyright date to 2018.
Removed Repair Process Engineering old point of contacts.
Added Repair Process Engineering new point of contact.
NENG2500 , "Dealer Service Tool Catalog", canceled replaced by , PERJ1017 , "Dealer Service Tools Catalog".
|16||Reworded Torque Turned fastener section.|
|15||Removed irrelevant image.|
© 2019 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).
This guideline covers fasteners that are used in transmissions, drivelines, and differentials. Most of the fasteners are common bolts. Since special bolts are used in some assemblies, the requirements for these bolts are also covered. Both the common special types of fasteners are used in any application. Most of the common bolts are reusable. Common bolts will provide equal services as new bolts. Reused bolts will provide equal service requirements as newer bolts. However, single use or common bolts that are indicated in this guide should not be reused.
When replacement parts are required for this product Caterpillar recommends using Caterpillar replacement parts or parts with equivalent specifications including, but not limited to, physical dimensions, type, strength and material.
Failure to heed this warning can lead to premature failures, product damage, personal injury or death.
|Media Number||Publication Type & Title|
|—||Applicable Disassembly and Assembly (D&A) Manuals|
|—||Applicable Operation and Maintenance (OMM) Manuals|
"Dealer Service Tools Catalog"
|SEBF8301||Reuse and Salvage Guidelines
"Inspection and Reuse of Critical Fasteners Used in All Engines"
|SEBF9066||Applied Failure Analysis
"Guideline for Examining Failed Parts"
Service Advisories, Service Letters, and Technical Service Bulletins
The most recent Service Advisories, Service Letters, and Technical Service Bulletins that are related to this component should be reviewed before beginning work. Often Service Advisories, Service Letters, and Technical Service Bulletins contain upgrades in repair procedures, parts, and safety information which pertain to the application or system using this component that is being repaired.
Tooling and Equipment
Note: The Tooling and Equipment in Table 3 is not an all inclusive list of Tooling required to perform every task within this document. Tooling needs may vary for the scope of work to be performed for each specific rebuild.
|— (1)||Personal Protective Equipment (PPE)||Personal Protection|
|Gauge Kit||Thread Yielding Checks|
|Thread Yielding Checks|
|Seal Pick||General Cleaning|
| Seal Pick
|—||Bright Incandescent Light||Visual Surface
|Magnifying Glass||Visual Surface
| Microscope (40-Power)
|—||Loctite 243||Bolted Joints - Extreme Flexing Applications|
|(1)||Refer to PERJ1017Special Publication, "Dealer Service Tools Catalog" for Personal Protective Equipment (PPE) part numbers suitable by geographic location and local safety standards.|
|(2)||Part of kit |
Clean bolts before conducting an inspection. Cleaning and inspecting ensure that no damage is hidden by grease or dirt. Use a wash tank or a coarse brush with a mild petroleum-based solvent. If bolts are bent or damaged, cleaning is not needed, and therefore, DO NOT USE BOLTS AGAIN.
Ensure that the solvent does not have any water contamination. Also, never use a chlorinated solvent. Surface pitting can be caused by either water or chlorine. Pits can cause areas of highly concentrated stress. These areas are called stress risers. Stress risers are more likely to result in failure of the bolt.
Mismatched or incorrect fasteners can result in damage or malfunction, or personal injury.
Take care to avoid mixing metric dimensioned fasteners and inch dimensioned fasteners.
REFER TO OMM MANUALS DEALER PUBS FOR SPECIFIC INSTRUCTIONS ON A PER JOINT BASIS.
Note: To improve the overall corrosion life and appearance of the machine, paint external fasteners after installation.
Bolted joints are typically designed to last the life of the machine or assembly. Bolts should be replaced at rebuild of the machine. Some joints carry much higher loads than others and will have a life limited to a portion of the machine or assembly life.
General Bolt Reusability
- If the bolted joint experienced a failure, DO NOT USE BOLTS AGAIN.
- NEVER reuse bolts from a joint where other bolts failed.
- Bolts should have lubricant applied prior to reassembly. NOTE: Refer to applicable Disassembly and Assembly manuals for per application instruction.
(B) Washer Face
(E) Thread Root
(F) Underhead Fillet Radius
The highest stress areas of a bolt.|
(F) Underhead Fillet Radius
(G) First thread root after the bolt shank.
(H) First engaged thread in mating part (the nut or tapped hole) when installed.
Note: A magnifying glass is useful in close inspection of surface irregularities.
Refer to Illustration 1 for the nomenclature of the bolt and areas that need thorough inspection. Examine closely the high stress areas within Illustration 2.
- Corrosion can damage bolts and cause pits which are stress risers. Stress risers will lower fatigue life of the bolt. Corrosion on the bolt shank is not acceptable. Mild corrosion on the head or end of the bolt is acceptable.
- Fretting Wear is caused by rubbing of two surfaces together under high pressure. This can create pitting or wear lines that are stress risers. Visible fretting wear on the bolt shank is not acceptable if felt by dragging a fingernail across.
- Fatigue damage occurs over time with high machine hours. The bolt has accumulated cyclic damage and cracks may have started. Fatigue usually occurs at the first engaged thread or the underhead fillet radius. Unfortunately, fatigue damage is generally not observable by a basic visual inspection. When significant hours are on the machine, the bolt should be replaced and not reused. Fatigue is greatly accelerated if a bolted joint failed or was found loose. Replace bolts even if no damage is apparent if the joint failed or was found loose.
- Damage (dings, dents), sharp notches, and cracks are not acceptable. Small dings and dents generally do not impact performance.
- If there is a concern for the amount of corrosion, wear, or damage, then DO NOT USE BOLTS AGAIN.
Example of checking for yielded threads. Illustration indicates excessive yield where threads of used bolt (1) will no longer nest with the treads of a new bolt (2) of the same part number.|
If threads of two bolts of same pitch and diameter do not mesh therefore exhibiting excessive yielding, then DO NOT USE AGAIN.
(1) Used Bolt
(2) New Bolt
Inspect bolt in Illustration 3. If there is yielding in the threads, or there are significant hours are on the machine, then DO NOT USE BOLTS AGAIN.
- Check the full LENGTH of bolt thread for damage (nicks, cracks, corrosion, or stripped).
- Check for excessive thread wear or thread galling. If threads have excessive wear or galling, then DO NOT USE BOLTS AGAIN.
- Check for excessive thread yield by ensuring that a nut will run up the full length of thread OR check for excessive bolt yield by overlapping threads of two similar parts end to end and ensure that the threads nest together. If bolts are found with excessive thread damage or yielding, then DO NOT USE BOLTS AGAIN.
- Inspect thread roots near first engaged thread. If any evidence of a crack is found in the thread root, DO NOT REUSE BOLT AGAIN.
- Inspect thread tips for dings, small dings (less than ½ the thread height are acceptable and will realign during assembly. Large dings on threads will damage the mating thread, DO NOT USE BOLT AGAIN.
Check shank for corrosion, pitting, cracks, wear, deformation, and straightness.
- Corrosion creates pits and stress risers which lower fatigue strength.
- Check for straightness by rolling bolt on smooth table with head off edge.
- Vertical lines from forging may be present on shank, but Open cracks are not acceptable.
- If significant fretting wear is present on shank or thread tips (indicates joint was moving), then DO NOT USE BOLT AGAIN.
Check the underhead fillet radius for nicks. The radius shall be smooth an even around the full diameter of the bolt. If a circular nick is present in the fillet radius, then DO NOT USE BOLT AGAIN.
Bolts should be used with a washer with enough internal clearance not to interfere with the fillet radius. If a washer is not used, the hole the bolt head surface mates to should have an internal chamfer to accommodate the fillet radius. A circular nick, scratch, or crack in the fillet radius will act as a stress riser reducing the fatigue life of the bolt. If a circular nick, scratch, or crack is present in the fillet radius, then DO NOT USE BOLT AGAIN.
Ground Body Bolts
Look for fretting wear on shank. If a significant wear step is present (can be felt with fingernail drag), then DO NOT USE BOLT AGAIN.
Adhesive Lock Bolts
Used in applications where the bolted joint undergoes extreme flexing. Replace with new bolts. If new bolts with preapplied adhesive cannot be procured clean the bolts and apply Loctite 243 to all the threads that will be engaged and also to the internal threads. Obtain new replacement bolts at first opportunity.
Note: The presence of oil or lubricant may prevent the adhesive from working. Clean and degrease the internal threads before reinstallation (the lock patch or Loctite will provide needed lubrication).
Torque and Turn Required Bolts
CAN BE and COMMONLY ARE REUSED
- Track bolts are all torque-turn and are reused at ½ track life at bushing turn.
- To build an engine it takes 2-4 reuses of the connecting rod (con-rod) bolts (tighten bolts in con-rod for machining, disassemble, assemble con-rod to crank with bearings, tighten to set bearings, untighten, and then final tighten).
Inspect bolt as per Illustration 3.
- If yielding found in threads, then DO NOT USE BOLT AGAIN.
- If there are significant hours on the machine, then DO NOT USE BOLT AGAIN.
Nylon Patch Lock Bolts
Used in applications with severe vibration. The bolts will have a nylon patch spray melted onto the threads. The nylon will resist the bolt free-turning out of the threads. These bolts may be reused as long as the patch provides more than hand force (without socket or wrench) resistance. These are typically reuseable 5+ times.
- Inspect nut body for any obvious issues. If issues like a crack are found, then DO NOT REUSE NUT AGAIN.
- Inspect the nut bearing face. If burrs, nicks, corrosion, or galling is present, then DO NOT REUSE NUT AGAIN.
- Inspect internal threads. If thread damage like stripped or galling is evident, then DO NOT REUSE NUT AGAIN.
- Inspect washer for any obvious issues. If the washer is bent or cracked, then DO NOT REUSE WASHER AGAIN.
- Inspect the washer bearing faces. If burrs, nicks, corrosion, or galling is present, then DO NOT REUSE WASHER AGAIN.
Visual Surface Inspection (VT)
Example of Visual Surface Inspection (VT) Tooling|
(A) Flashlight (or adequate light source)
(B) Magnifying Glass
(C) Tape Measure (or other measuring device)
(D) Inspection Mirror
Refer to Tooling and Equipment Table 3 for part numbers.
Components and welds that are to be tested using PT, MPT, or UT shall first be subject to a Visual Surface Inspection (VT). VT is often the most cost-effective inspection method and requires little equipment as seen in Illustration 4. Personnel performing VT shall either be trained to a company standard or have sufficient experience and knowledge regarding the components being inspected. Personnel performing VT shall take routine eye exams.
|Visual Surface Inspection (VT) Standards|
|Visual Surface Inspection (VT)||EN-ISO 5817
|EN-ISO 5817 - Level B
AWS D1.1 - Table 6.1