We recently overhauled a Grove RT 9130E boom at Chirano Gold Mine in Ghana.
Grove recommends that the retract cables are renewed every 7 years, and we also took this opportunity to replace all the wear pads / slides inside the boom.
When it comes to Grove Power Booms we refer to “The 7 Year Itch” as every seven years these critical parts must be replaced.
From the Grove Service Manual: Wire Rope Replacement (All Wire Rope)
No precise rules can be given for determination of the exact time for replacement of wire rope. Continued use or replacement of wire rope depends largely upon the good judgement of an appointed and qualified person who evaluates the remaining strength in a used rope after allowance for any deterioration disclosed by inspection.
Wire rope MUST be taken out of service when any of the follwing exist:
1. In running ropes, six randomly distributed broken wires in one lay or three broken wires in one strand in one lay.
2. Wear of one-third the original diameter of outside individual wires. Kinking, crushing, bird caging, or any other damage resulting in distortion of the rope
3. Evidence of any heat damage from any cause.
4. Reductions from nominal diameter of more than:
- 1/64 inch for diameters up to and including 5/16 inch.
- 1/32 inch for diameters 3/8 and 1/2 inch inclusive.
- 3/64 inch for diameters 9/16 to 3/4 inch inclusive.
- 1/16 inch for diameters 7/8 to 1 1/8 inches inclusive.
- 3/32 inch for diameters 1/14 to 1 1/2 inches inclusive.
5. In standing ropes, more than two broken wires in one lay in sections beyond end connections or more than one broken wire at an end connection.
6. Grove recommends that for cable extended booms, a single damaged wire rope assembly shall require replacement of the entire set of extension cables.
7. Grove recommends for cable extended booms, that boom extension cables be replaced every seven (7) years.