COVER 2P2439 - Caterpillar

Introduction
Improvements are now available for accumulator arms on the listed Felling Heads. The steps to complete the improvements are described within this Special Instruction.Do not perform any procedure in this Special Instruction until the information has been read and understood.Reference Material
ReferenceRefer to Special Instruction, REHS1841, "General Welding Procedures" for information on welding.Improvements for the HF201 (S/N: PAM1-119) Felling Heads
Illustration 1 g02237953
(A) Area to be ground for stop assembly installation
Remove the paint from the accumulator arms. Start the removal at the edge of the front plate and continue 152.40 to 177.80 mm (6 to 7 inch) rearward.
Illustration 2 g02237693
(B) 48.3 mm (1.90 inch) (C) 44.8 mm (1.76 inch) (D) 7.9 mm (0.31 inch) (E) Radius of 300 degrees (F) 142.1 mm (5.60 inch) (G) 12.1 mm (0.475 inch) (H) 19.1 mm (0.75 inch) (J) 8 mm (0.315 inch) at 45 degrees
Manufacture the stop assembly.
Illustration 3 g02238263
(K) Stop assembly placed in location
Place stop assembly on to the accumulator arm at the prepared location from Step 1.
Tack weld stop (K) into place.
Illustration 4 g02238274
(K) Stop assembly placed in location (L) 6.35 mm (0.25 inch) fillet weld of 142.1 mm (5.60 inch) in length (M) 6.35 mm (0.25 inch) fillet weld of 44.8 mm (1.76 inch) in length
Secure stop (K) into place with a 6.35 mm (0.25 inch) fillet weld at both weld location (L) and weld location (M) .
Finish this step by cleaning the welded area.
Finish the improvement by painting the reworked area with an approved protective coating of paint.
Repeat Steps 1 through 6 on the other accumulator arm.Improvements for the HF201 (S/N: PAM120-131) and the HF221 (S/N: PAJ1-333) Felling Heads
Illustration 5 g02238774
(A) Accumulator arm in stock configuration (B) Accumulator arm in improved configuration (C) 12 mm (0.470 inch) at 45 degrees
Bevel the tip of accumulator arm (A) to measurement (C) .
Repeat this step on the other accumulator arm.