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:

TEBE0332-02

Show/hide table

12Sep2013

(Revised 01May2014)

U-422

A-290

D-352

O-354

Show/hide table

*Priority*	PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE TORQUE TUBE WELD ON CERTAIN 795F AC OFF-HIGHWAY TRUCKS
7051		PI32229

Show/hide table

NOTE:

This Program must be administered as soon as possible. When reporting the repair, use "PI32229" as the Part Number and "7751" as the Group Number, "56" as the Warranty Claim Description Code and "T" as the SIMS Description code. Exception: If the repair is done after failure, use "PI32229" as the Part Number, "7751" as the Group Number, "96" as the Warranty Claim Description Code, and "Z" as the SIMS Description Code.

Show/hide table

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.

Show/hide table


NOTE:	This Revised Service Letter replaces the 12Sep2013 (Revised 19Nov2013) Service Letter. Changes have been made to the Action Required and Service Claim Allowances.

Show/hide table

COMPLETION DATE	TERMINATION DATE
31Mar2014	30Sep2014

PROBLEM

Show/hide table

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

Show/hide table

Model	Identification Number
795F AC	ERM00151-00284

PARTS NEEDED

Show/hide table

No parts needed for this program

ACTION REQUIRED

Show/hide table

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. 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".

Show/hide table

Image1

OWNER NOTIFICATION

Show/hide table

Owners in the following countries will receive the attached Owner Notification:
US
Canada

SERVICE CLAIM ALLOWANCES

Show/hide table

Caterpillar		Dealer Suggested		Customer Suggested
Parts %	Labor Hrs%	Parts %	Labor Hrs%	Parts %	Labor Hrs%
100%	100%	0%	0%	0%	0%

Show/hide table

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.

Show/hide table

PARTS DISPOSITION

Show/hide table

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

MAKE EVERY EFFORT TO COMPLETE THIS PROGRAM AS SOON AS POSSIBLE.

Show/hide table

EXAMPLE COPY OF OWNER NOTIFICATION

XYZ Corporation
3240 Arrow Drive
Anywhere, YZ 99999

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

MODELS INVOLVED - 795F AC Off-Highway Trucks

Dear Cat Product Owner:

The torque tube needs to be rewelded on the products listed below. The existing welds on the torque tube can crack, putting the torque tube and adjoining plate assembly at risk for failure. You will not be charged for the service performed.

Contact your local Cat dealer immediately to schedule this service. The dealer will advise you of the time required to complete this service.

If you are no longer the owner of this product(s), please contact your local Cat dealer so that our records can be updated. Please refer the dealer to their Service Letter dated 12Sep2013 when scheduling this service.

We regret the inconvenience this may cause you, but urge you to have this service performed as soon as possible to prevent unscheduled downtime.

Caterpillar Inc.

Identification #(s)

Attached to 12Sep2013 Service Letter

Rework Procedure

Show/hide table

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. 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.