Broderson RT-400-A, Operation And Maintenance Manual

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3-25
CAUTION
For a correct assembly, it is necessary to have a minimum pre-load of 5% of the cable
breaking force. The cable breaking force depends on the diameter and of the cable type,
and it must be indicated on the cable certificate.
6. Slowly rotate the hoist while applying tension on the cable in front of the boom. Wear heavy
leather gloves and wrap rags around the cable to wipe off any dirt from the cable. Keep
hands away from the sheaves and hoist drum while the cable is moving.
7. After two turns of the drum, stop the hoist and push the cable into the drum groove if it has
come out.
8. Slowly rotate the drum until the first layer of cable is on the drum. If any gaps between the
rope appear, back up the hoist and rewind. There must be no gaps in the first layer.
9. After the first layer is on the drum, the hoist may be turned a little faster until the remainder
of the cable is installed.
10. Leave about 40 feet (12 m) of cable on the ground to install the sheave block. The sheave
block must be used for cable preloading to ensure enough rope can be spooled off the hoist
drum. See the
Operation Section
for instructions on reeving and wedge socket attachment.
11. Install the cable retainer pins and cotters in the tip sheave plates.
12. For the cable preloading, set the outriggers and attach a load of about 3000 pounds (1300
kg). EXTEND the boom fully. Position the load at a 10-foot (3m) load radius over the side
of the crane. HOIST UP and LOWER the load three times and check winding of the rope on
the hoist.
13. Attach about 8000 pounds (3600 kg) and repeat. Be sure that the cable winds evenly.
14. Never lift more than the rated load on the Capacity Chart for the parts-of-line and type of
wire rope being used.
15. Lubricate the cable as recommended in the
Wire Rope Lubrication
section. Inspect, main-
tain, and replace the cable in accordance with ASME B30.5, Section 5-2.4.
W A R N I N G
All cut ends on ropes must be welded. Failure to weld cut ends may result in rope failure,
furthermore leading to property damage, injury, or death.