2008/07/07 Caterpillar

Excavator:

345B LSeries II (S/N: CCC1-UP; FEE1-UP)

345B (S/N: 7KS1-UP)

345C (S/N: MTE1-UP)

345C L (S/N: FPC1-UP; SPC1-UP; GPH1-UP; GCL1-UP; LYS1-UP)

The variation in the manufacturing process of the 6.90 m (7.55 yd) reach boom for Excavators has been reduced. The reduced variations improve the overall quality of the booms. Four critical areas of production have been identified.

The effectivity of the improvements are listed in Table 1. Refer to Illustration 1 in order to see the location of the improvements that are for a typical boom for a 345 Excavator.

The following is a summary of the actions that have been performed:

• The welds are no longer welded by an operator for the internal baffle plates. The welds are now completed by automated welding. An improved inspection process of the welds for the baffle plates is performed.

• Tighter tolerances for the gaps in the weld joints have been established for the manufacturing process. New gauges are used for the verification of the width of the gaps in the welded joints. The gaps are inspected for conformance. The gaps in the welded joints that do not conform are repaired.

• The welding process uses two run off tabs for the top and bottom cross welds. The welding process uses two run off tabs to ensure the beginning and the end of the welds conform to weld specifications.

• The quality of the welds are validated by an ultrasonic flaw detection unit.

Illustration 1	g01592453
Locations of improvement on a typical 345 Excavator boom (A) Butt welds on the upper plates of the boom (B) Fillet welds for the baffle plates in the boom (C) Butt welds for the side plates of the boom