PRODUCT SUPPORT PROGRAM FOR REWORKING THE 284-3194 BOOM ON CERTAIN 424 II BACKHOE LOADERS Caterpillar

PRODUCT SUPPORT PROGRAM FOR REWORKING THE 284-3194 BOOM ON CERTAIN 424 II BACKHOE LOADERS

Usage:

TEBE1092-00

Show/hide table

26Mar2014

D-156

Show/hide table

*After Failure Only*	PRODUCT SUPPORT PROGRAM FOR REWORKING THE 2843194/">284-3194 BOOM ON CERTAIN 424 II BACKHOE LOADERS
6501		PS52637

Show/hide table

NOTE:

This Program can only be administered after a failure occurs. The decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS52637" as the Part Number and "7755" as the Group Number. Use "96" as the Warranty Claim Description Code and use "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

TERMINATION DATE

31Mar2016

PROBLEM

Show/hide table

The existing 2843194/">284-3194 Boom may develop a crack, in certain extreme work applications, on certain 424 II Backhoe Loaders. If the existing boom cracks, welding rework needs to be carried out for the observed failure mode.

AFFECTED PRODUCT

Show/hide table

Model	Identification Number
424 II	JRC03421, 3433-3435, 3439-3483, 3486-3546, 3548, 3551-3628, 3651-5990, 5997-6352, 6354, 6356-6481, 6483-6486, 6488-6682, 6685-7010

PARTS NEEDED

Show/hide table

Qty	Part Number	Description
1	2843194	BOOM AS
1	2988573	FILM-CAT
1	2988574	FILM-CAT
In order to allow equitable parts availability to all participating dealers, please limit your initial parts order to not exceed 2% of dealership population. This is an initial order recommendation only, and the ultimate responsibility for ordering the total number of parts needed to satisfy the program lies with the dealer.

ACTION REQUIRED

Show/hide table

Welding rework is to be carried out based on the given Rework Procedure if the boom cracked at the following areas. Refer the Images located in the Rework Procedure.

1. Boom foot end
2. Toe crack on boom top and bottom weld
3. Bottom nose end
4. Curvature area

In case the field repair fails below 5000 hrs / 2.0 years from date of machine commissioning (which ever is earlier), contact the CIPL Service representative for fresh boom (09 change level) replacement.

Note: Apply new 298-8573 (left hand) and 298-8574 (right hand) Cat Films after new boom replacement for both sides.

Show/hide table

SERVICE CLAIM ALLOWANCES

Show/hide table

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%
0-3000 hrs, 0-12 mo	100.0%	100.0%	0.0%	0.0%	0.0%	0.0%
3001-5000 hrs, 13-24 mo	100.0%	100.0%	0.0%	0.0%	0.0%	0.0%

Show/hide table

NOTE: This is a 8.0-hour job
Note: Labor hours applicable for weld rework.

Show/hide table

PARTS DISPOSITION

Show/hide table

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

Rework Procedure

Show/hide table

GENERAL GUIDELINES APPLICABLE FOR ALL FAILURE MODES

TOOLS REQUIRED:

1. Angle Cutter with 6" Wheel
2. Hand Drilling M/C
3. 4 or 5mm Drill Bit
4. Center Punch
5. Hammer
6. Measuring Tap or Scale
7. Welding Set
8. Welding Shield and Goggle
9. Welding Apron
10. Dp Test Kit

CONSUMABLES REQUIRED FOR REWORK:

E 7018 Electrode ?Advani/ESAB or any other reputed brand - as required.

WELDER QUALIFICATION / SAFETY:

a) All welders must be qualified for Groove / fillet welding in 1G / 1F and 3G/3F positions as outlined in the current ANSI/AWS standards.

b) The welding operator must also have used the welding process during the last six months or be re-certified for this purpose before welding.

c) Personal protection should be provided. Weld fumes and gases can be dangerous to health. Ultraviolet rays from the weld arc can injure eyes and burn skin.

ELECTRODE / CHARACTERISTICS:

The Manual Metal Arc Welding (MMAW) process shall be used with E7018 welding electrode. The weld deposited by these electrodes will have the following minimum mechanical properties:

TENSILE STRENGTH - 480 MPa
YIELD STRENGTH - 400 Mpa
ELONGATION - 22%

These are low hydrogen electrodes and must be stored in an oven at 120 degrees Celsius when not in use.

ELECTRODE DIAMETER AND CURRENT SETTINGS FOR WELDING:

DIAMETER LENGTH CURRENT IN AMPS
2.5mm 350mm 60 - 80

INSPECTION:

The weld shall be free from cracks, porosity, undercut, and incomplete fusion.

DYE PENETRANT TEST:

Dye penetrant testing is a non-destructive testing method for detecting discontinuities open to the surface such as cracks, seams, laps, surface weld flaws, etc.

MATERIALS REQUIRED: Spray Type

CLEANER: This removes dirt before dye application and dissolves the penetrant making it possible to wipe the surface clean.

PENETRANT: This solution is highly visible, and will seep into openings at the surface of a part by means of capillary action.

DEVELOPER: This provides a blotting action, bringing the penetrant out of the discontinuities and providing a contrasting background to increase the visibility of the penetrant indications.

PROCEDURE FOR DYE PENETRANT (DP) TESTING:

a) Remove any loose scale and dirt by wiping. Remove oils and coatings using solvents, or grinding.

b) Wipe the area to inspect with a solvent dampened cloth to remove remaining dirt and allow the area to dry.

c) Apply penetrant by spraying to the entire area to be examined.

d) Allow 10 to 15 minutes for penetrant to soak.

f) After the penetrant has been allowed to dwell, remove most of the excess penetrant with clean, dry wipes. The last traces of penetrant should be removed with the cleaner solvent dampened cloth or wipe. Allow the area to dry thoroughly.

g) Apply an even, thin layer of developer over the area being inspected. A few very thin layers are a better application method than one thicker layer. Allow the developer to dry completely for 10 ? 15 minutes before inspecting for surface discontinuities.

h) The developer will act to draw entrapped penetrant out of the discontinuity. A red stain on the developer indicates a possible surface discontinuity.

i) Clean the area of application of the developer with solvent cleaner.

j) If any line indicating with penetrant, mark the area as crack for rework

PROCEDURE FOR FAILURE MODE 1: FOOT END CRACK

1. Park the machine at convenient location on level ground. Keep the rear Backhoe structure at extended position and keep the Hoe Bucket at rest on the ground.

2. If the boom rework is done with M/C level (optional), remove battery earth connection.

3. Complete a visual check for any vertical crack presence on the boom assembly, on the side plate. Refer to Image1.2.1 and 1.2.2.

4. Grind the crack area smooth in side plate in order to remove paint for DP test.

5. Conduct DP Test to check the extent of crack. Refer the DP test guidelines.

Image1.2.1

Image1.2.2

6. Grind to a depth of 6mm and width of 6mm in order to remove the weld crack. Refer to Image1.3.1.

Image1.3.1

7. Carry out the DP test to ensure the defect is removed. Clean the area with cleaner in order to remove the DP particles whenever the welding is carried out after DP test.

8. Carry out the weld rework in the vertical position (3G position) and ensure that a 45-degree angle is maintained to sidewall fusion. Provide stiffener at open end in order to avoid weld distortion and to ensure the bore inline.

Refer to Image1.4.2.

Image1.4.2

9. Conduct DP Test to ensure a defect free weld after root run.

10. After ensuring a defect free weld in the DP test, complete the welding with a 2nd pass.

11. Grind the welded area smooth and conduct DP Test to ensure a defect free weld.

12. Paint the reworked area and connect the battery earth, if disconnected.

13. Reassemble the boom and reconnect all hydraulic lines that were disconnected.

Refer to Image1.5.1.

Image1.5.1

PROCEDURE FOR FAILURE MODE 2: TOE CRACK ON BOOM TOP AND BOTTOM WELD

1. Complete a visual check for any crack presence on the boom assembly side, near the stick mounting.

2. If the M/C level rework is done, boom removal is not required. Clean the area where the crack is found.

3. Grind the crack area smooth to remove paint for DP test.

Refer to Image1.6.1.

Image1.6.1

4. Conduct DP Test to check the extent of the crack.

5. Mark a point 5mm above the crack initiation point and drill a 4mm diameter hole as shown.

Refer to Image1.7.1 and 1.7.2.

Image1.7.1

Image1.7.2

6. Make chamfer (6mm x 45 Degrees) for welding. Ensure that the crack line is removed by grinding in side and the plate bottom smooth. Ensure the root gap is maintained between 0 to 2mm.

7. Carry out the weld rework in vertical position (3G) and ensure good root fusion.
8. Conduct DP Test to ensure a defect free weld after root run.

9. After ensuring a defect free weld in DP, complete the welding with a 2nd pass.

Refer to Image1.8.1 and 1.8.2.

Image1.8.1

Image1.8.2

10. Grind the welded area smooth and conduct DP Test to ensure a defect free weld.

11. Paint the reworked area and connect the battery earth, if disconnected.

12. After rework, reassemble the boom and connect all hydraulic lines that were disconnected.

Refer to Image1.9.1.

Image1.9.1

PROCEDURE FOR FAILURE MODE 3: BOTTOM NOSE END CRACK

1. Park the machine at convenient location on level ground. Keep the rear Backhoe structure at extended position and keep the Hoe Bucket at rest on the ground.

2. If the boom rework is done with M/C level (optional), remove battery earth connection.

3. Perform visual check for bottom nose end crack.

Refer to Image1.10.1.

Image1.10.1

4. Conduct DP Test to check the extent of crack. Refer the DP test guidelines.

5. Remove the weld thoroughly by grinding.

6. Complete root weld and fill the gap.

7. Ensure the welding holder angle is 45-degrees to ensure the side wall fusion.

8. Grind the weld, if required, and conduct DP Test to ensure a defect free weld.

9. Paint the reworked area and connect the battery earth, if disconnected.

10. After rework, reassemble the boom and connect all hydraulic lines that were disconnected.

FOR FAILURE MODE 4: CURVATURE CRACK

1. Park the machine at convenient location on level ground. Keep the rear Backhoe structure at extended position and keep the Hoe Bucket at rest on the ground.

2. If boom rework is done with M/C level (optional), remove the battery earth connection.

3. Use the DP Test guidelines and confirm the crack. Grind the cracked area and complete the welding rework. Grind the weld, if required, and conduct DP Test to ensure a defect free weld. Paint the reworked area and connect the battery earth, if disconnected.

4. After rework, reassemble the boom and connect all hydraulic lines that were disconnected.

Refer to Image1.12.1.