CONTROL GP-ENG RATINGS ELEK 1433261 - Caterpillar

Illustration 2 g02416540
SERVICING position
While the machine is in the SERVICNG position, remove the bucket from the stick. Refer to the applicable Disassembly and Assembly manual for your machine for the correct removal procedure.
Remove the stick from the boom. Refer to the applicable Disassembly and Assembly manual for your machine for the correct removal procedure.
The work can be done with the boom on the machine or with the boom off the machine. Refer to the applicable Disassembly and Assembly manual for your machine for the correct removal procedure.
Remove all the hoses and hardware from the boom.Preparing for Welding
Remove the paint, rust, dirt, and scale with a wire brush or by buffing or grinding. Shot blasting all the work areas will also remove the foreign material.
Remove any oil or grease that is on the boom with a Caterpillar approved solvent.
Cover all the finished bores and threads. Finished bores and threads must be protected from all of the following items: foreign material, welding, gouging, and paint spatters. Do not remove the covers until the boom is painted.
Illustration 3 g02470583
Steel strip diagramRefer to Table 1 for the specifications of the steel strip.
Table 1
Steel Strip Dimensions    
L     520 mm (20.5inch)    
W     (38 mm)(1.5inch)    
T     (14 mm)(0.6inch)    Note: The steel strip should be fabricated by the dealer.
Illustration 4 g02470639
Steel strip positioning (1) Steel strip (2) Tack weldNote: Make sure that the steel strip is securely tacked to theboom nose before starting the repair procedure.Weld Procedure:
Illustration 5 g02470678
Weld gouging (3) Old weld (4) After gouging
Use an air carbon arc torch or a grinder to gouge out the crack on the U-shape plate completely. Refer to Illustration 5.
Use the dye penetrant to inspect the gouged area in order to ensure that the crack has been removed completely.
Illustration 6 g02470696
Bevel diagram
Use a grinder to form a 25 (+5/-2°) degree bevel on the U-shape plate. Refer to Illustration 6.
Illustration 7 g02470736
Section view of the weld
Weld along the crack in the U-shape plate to ensure the root weld penetration. Refer to Illustration 7.Note: The ambient temperature must be a minimum of 16° C (61° F) to perform the repair.
Illustration 8 g02470740
Grind the weld
Grind the weld until the top face is smooth with U- shape plate. Remove the crosshatched section of the weld. Refer to Illustration 8.Painting and Coating the Boom
Relieve the stress in all the welds by needle peening. A wire brush or a grinder can also be used to clean the welded area.
Use a Caterpillar authorized paint product to paint the welds and reinforcement plates.
Cover all the bores, threaded holes, and cylinder rods before painting.
Remove all the protective covers from the bores and threads once the paint has dried.
The bores must be free of paint and grease prior to assembly of the bearings.Apply the required amount of lubricant to the bores, bearings, and threads. Refer to the Operation and Maintenance Manual and the Service Manual for lubrication instructions and quantities.Installation of the Boom, the Stick, and the Bucket
Prepare the machine and parts for reassembly. The weight of the