Reinforcement Of Boom Heads Caterpillar

Reinforcement Of Boom Heads

Usage:

TELESCOPIC MATERIAL HANDLERSRT50 (4XG);
RT50 SA (8DJ)

Problem:

Under some operating conditions, welds on the boom head may crack in the areas shown in Illustration 1.

Solution:

The cracks can be repaired and the area reinforced using following parts and the attached repair procedure.

PARTS REQUIRED:

1. 1 - 814746 Underside Plate

2. 1 - 814744 Side Plate R.H.

3. 1 - 814738 Side Plate L.H.

4. 2 - 814742 Hook Plate

5. 2 - 814778 Cover Plate

6. 1 - 814741 Cheek Plate R.H.

7. 1 - 814740 Cheek Plate L.H.

8. 1 - 814731 Pipe

9. 1 - 814730 Pipe

10. 1 - 6R8927 Pipe

11. 1 - 6R8926 Pipe

12. 2 - 6R8928 Bracket

^*If required - machines equipped with auxiliary hydraulic services only.

For identification purposes, parts (1 - 7) listed above, are shown in Illustration 8.

REPAIR PROCEDURE:

NOTE: Use AWS E7018 Electrodes, or MIG weld wire AWS ER705-6, or equivalents for all welds in this procedure. Weld details are shown in the illustrations.

1. Remove the attachment carriage and extend the boom approximately two meters (six feet). Support the boom with the head clear of the ground by positioning a suitable support stand or bracing under number one boom section.

2. If the machine is equipped auxiliary hydraulic services, remove the quick release fittings, steel pipes and brackets and plug the open ports of the control valve. Retain all of the hydraulic fittings and hardware. Discard the steel pipes and brackets

3. Remove all paint, oil and dirt from the boom head and inspect for cracks.

4. Vee out and repair any cracks.

5. Mark off and grind out the vertical welds at the rear of the boom head side plates over the length shown in Illustration 1. Prepare the ground edge of the side plates with a 45°, 8 mm (.31 in) wide chamfer.

6. Cut back the underside plate of the boom head and prepare with a 45°, 8 mm (.31 in) wide chamfer shown in Illustration 2.

7. Cut back the underside plate of the the boom section to the dimensions shown in Illustration 3.

8. Weld plate (1) in position as shown in Illustration 4.

9. Position side plates (2) and (3) and weld in position as shown in Illustration 5.

10. Weld hook plates (4), and cover plates (5) to the right and left cheek plates (6) and (7) as shown in Illustration 6.

11. Fully weld cheek plates (6) and (7) in position on the boom head as shown in Illustration 7.

12. Clean and paint as required. 13. Install brackets and steel pipes (8) through (12), as required, with retained hydraulic fittings.

ILLUSTRATION 1