PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE TORQUE TUBE WELD ON CERTAIN 795F AC OFF-HIGHWAY TRUCKS Caterpillar

PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE TORQUE TUBE WELD ON CERTAIN 795F AC OFF-HIGHWAY TRUCKS

Usage:

TEBE2102-00

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15Oct2014

K030
K042

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Containment - Before/After (Limited distribution)	PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE TORQUE TUBE WELD ON CERTAIN 795F AC OFF-HIGHWAY TRUCKS
7051 0679		PS90422

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NOTE:

Caterpillar’s obligations under this Service Letter are subject to, and shall not apply in contravention of, the laws, rules, regulations, directives, ordinances, orders, or statutes of the United States, or of any other applicable jurisdiction, without recourse or liability with respect to Caterpillar.

NOTE:

This Containment Program can be administered either before or after a failure occurs. In either case the decision whether to apply the Program is made by the dealer and service rep. Obtain the service reps Goodwill Approver Code before completing the repair. EAME dealers should use their standard Industry Group specific goodwill approval codes. The Goodwill Approver Code must be included when submitting the claim.

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NOTE:	When reporting the repair, use "PS90422" as the Part Number and "7777" as the Group Number. If administered before failure, use "56" as Warranty Claim Description and "T" as the SIMS Description Code. If administered after failure, use "96" as Warranty Claim Description Code and use "Z" as the SIMS Description Code.
NOTE:	The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.

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TERMINATION DATE

31Oct2015

PROBLEM

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The weld needs to be reworked where the 312-2178 Torque Tube meets the 279-9647 Plate on certain 795F AC Off-Highway Trucks. The existing weld can crack, putting the torque tube and plate assembly at risk for failure. This failure has been reported as early as 1500 machine hours.

AFFECTED PRODUCT

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Model	Identification Number
795F AC	ERM00180-00181, 185, 187, 209-210

PARTS NEEDED

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No parts needed for this program

ACTION REQUIRED

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Reweld torque tube and plate weld joint on the right and left hand sides of the machine. Refer to the attached Rework Procedure. Both sides of the torque tube must be repaired before returning the machine to service. Reference REHS4441 for additional information regarding general welding procedures and inspections.

When applicable, it is recommended that the 15Jul2013 Service Letter PS43959 be performed sequentially while the machine is down for this program.

NOTE: Do not remove welds from the inside frame and outside frame at the same time. Frame rail misalignment may occur. Remove and repair welds one Program at a time.

Note: Record a description of the location and length of all cracks found. This information must be included in the comments section of the claim. If no cracks were found, report "No cracks found".

Note: Record all non-OEM attachments to the frame in the affected area of the frame. This information must be included in the comments section of the claim.

Note: Removal of the truck body is not allowed in the program.

Note: Upon removal of the weld, inspect the affected area to ensure no cracks are present on the torque tube or plate. Work with your dealer technical communicator to immediately contact the Dealer Solutions Network (DSN) if cracks are found on the torque tube or plate as additional repair procedures will need to be developed.

During repair verify that the entire crack has been removed utilizing both visual (VT) and magnetic particle (MT) inspection as described in the "Crack Removal, Inspection Verification, and Joint Preparation" section of REHS4441 "Procedure for the Inspection, Repair, and Component Replacement on the Frame of the 795F AC Off-Highway Truck".

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Image1

SERVICE CLAIM ALLOWANCES

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Product smu/age whichever comes first	Caterpillar		Dealer Suggested		Customer Suggested
Product smu/age whichever comes first	Parts %	Labor Hrs%	Parts %	Labor Hrs%	Parts %	Labor Hrs%
0-12000 hrs, 0-36 mo	100.0%	100.0%	0.0%	0.0%	0.0%	0.0%

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NOTE: This is a 150.0-hour job
This is a 150-hour job to rework both left and right sides of the torque tube. An allowance of $1,000 for contamination control material and replacement seals can be claimed.

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PARTS DISPOSITION

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Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.

Rework Procedure

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Refer to the Service Manual if/as necessary.

Prepare the machine for maintenance. Refer to SEBU8349 "Prepare the Machine for Maintenance."

Remove components and hardware as needed to access weld. Scribe reference lines before removing fixed hardware to ensure proper reinstallation.

Image1.1.1

Crack is occurring in fillet weld between the stamp plate and tube, primarily on the stamp plate side of the fillet weld (Image 1.2.1).

Remove crack and entire fillet weld (360?) by arc gouging and grinding. Verify the crack is completely removed by PT or MT inspection. Exercise caution to not gouge the tube during this process.

Using PT or MT, inspect the area to ensure no cracks are present on the tube or plate. Work with your dealer technical communicator to immediately contact the Dealer Solutions Network (DSN) if cracks are found on the torque tube or plate as additional repair procedures will need to be developed.

Image1.2.1

Image1.2.2

Illustration (image 1.3.1) of the weld and crack removed. Nominal gap between the tube and the plate is 3.5 mm, but may vary from 0-7 mm.

Image1.3.1

Create a chamfer as shown (image 1.4.1) on the end of the stamped plate with arc gouging and grinding (360?). Clean chamfer with grinding before welding. Exercise caution to not gouge the tube during this process.

Image1.4.1

Weld stamped plate to tube according to weld geometry shown in the illustration (image 1.5.1). Weld from 6 to 12 o?clock clockwise and then counterclockwise. Weld can be broken into segments to reposition. Offset the starts and stops between passes by 50 mm.

Note: Ensure a maximum distance of 2mm from front toe of weld to outside lip of plate.

Image1.5.1

Add weld to existing weld on the outside diameter of the plate until weld size is as shown in illustration (image 1.6.1). Weld from 6 to 12 o?clock clockwise and then counterclockwise. Weld can be broken into segments to reposition. Offset the starts and stops between passes by 50 mm.

Note: Ensure a maximum distance of 2mm from front toe of weld to outside lip of plate.

Inspect all welds according to criteria shown in REHS4441. Repaint reworked areas.