DAMPER GP 4287539 - Caterpillar

Illustration 1. Typical location of cracks.Improved welding methods and other design changes have been made to these excavators at the factory. If weld cracks are a problem on a 215 Excavator, follow these steps to make repairs.
1. Inspect the area around the top ring of the carbody assembly for cracks in the weld joints. See Illustration 1. Cracks can be repaired if they are between 152 mm (6") and 305 mm (12") long. Cut out the cracks and weld them as shown in Illustration 2. If the joints crack again after they have been repaired the first time, a reinforcement ring can be fabricated and installed as shown in the steps that follow.2. Use the disassembly and assembly module as a guide and remove the carbody assembly.3. Weld the cracks as described in Step 1.
Illustration 2. Make repair welds as shown.4. Fabricate a reinforcement ring to the dimensions shown in Illustrations 3 and 4.5. Install the reinforcement ring as shown in Illustration 5.6. After installation of the reinforcement ring check the top ring for distortion. This distortion caused by the weld repair can result in high loading of the swing bearing and short service life of that bearing. Machine the top ring to a flat condition. No more than 1.5 mm (.06") of material is to be removed.7. Assemble the machine and check its operation.
Illustration 3. Dimensions for fabrication of reinforcement ring.
Illustration 4. Views and sections from Illustration 3.
Illustration 5. Weld for reinforcement ring.