Page 37 - Safety and health in construction

Lifting appliances and gear

(a) a rigid member should be used to maintain the correct distance between the wheels;

(b) they should be equipped with struts to prevent them from dropping if a wheel
breaks or the derrick is derailed.

5.3.6. The length of a derrick jib should not be altered without consulting the
manufacturer.

5.3.7. The jib of a scotch derrick crane should not be erected within the
backstays of the crane.

Guy derricks

5.3.8. The restraint of the guy ropes should be ensured by fitting stirrups or
anchor plates in concrete foundations.

5.3.9. The mast of guy derricks should be supported by six top guys spaced
approximately equally.

5.3.10. The spread of the guys of a guy derrick crane from the mast should be not
more than 45 from the horizontal.

5.3.11. Guy ropes of derricks should be equipped with a stretching screw or
turnbuckle or other device to regulate the tension.

5.3.12. Gudgeon pins, sheave pins and foot bearings should be lubricated
frequently.

5.3.13. When a derrick is not in use, the boom should be anchored to prevent it
from swinging.

5.4. Gin poles

5.4.1. Gin poles should:
(a) be straight;

(b) consist of steel or other suitable metal or straight-grained timber free from knots;
(c) be adequately guyed and anchored;
(d) be vertical or raked slightly towards the load;

(e) be of adequate strength for the loads that they will be required to move.

5.4.2. Gin poles should not be spliced and if a gin pole is composed of different
elements, they should be assembled in conformity with their intrinsic material strength.

5.4.3. Gin poles should be adequately fastened at their feet to prevent
displacement in operation.

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