How to use wire rope safely

As an important working part and common pick-up tool of hoisting machinery, steel wire rope is widely used in hoisting operation.

1. The steel wire rope shall be used according to the technical data of the factory. When there is no technical data, the single wire breaking force test shall be carried out.

2. The steel wire rope shall be selected according to its mechanical properties and equipped with a certain safety factor. The diameter of steel wire rope and matching pulley shall not be less than that shown in Table 1.

3. The steel wire rope shall be soaked with oil regularly.

4. When fixing the steel wire rope head with rope clamp, the rope clamp plate shall be located on the main stress side of the steel wire rope and shall not be set cross; The spacing of rope clamps shall not be less than 6 times the diameter of steel wire rope, and the number of rope clamps shall meet the requirements of Table 2.

5. The insertion length of the insertion rope or sleeve shall not be less than 15 times the diameter of the steel wire rope, and shall not be less than 300mm. The rope sleeve just installed shall be sampled and tested with 125% of the allowable load.

6. The steel wire rope passing through the pulley and drum shall not have joints. The ratio of the groove bottom or thin waist diameter of the pulley drum to the diameter of the steel wire rope shall meet the following requirements: when the hoist is driven, the mechanical transmission of the pulley shall not be less than 11 and the manual transmission shall not be less than 10.

7. Uncoil with correct method before using new steel wire rope. Put the steel wire rope drum on the rotating shaft, and then pull one end of the steel wire rope to make the drum rotate slowly and straighten all rope loops. The steel wire rope drum shall not be stacked vertically on the ground, and then the steel wire rope shall be stretched horizontally, so that the twisting force of the steel wire rope can not be fully released, which will break and twist the steel wire rope and cause serious damage. When in use, the crane pulley will wind and rotate, making it unable to work normally.

8. The steel wire rope shall be stored in a well ventilated and non humid room, and shall be placed on a shelf or hung.

9. The steel wire rope shall not contact with the welding wire or other wires, otherwise it is easy to burn the steel wire rope and cause danger.

10. The lifting and luffing mechanism of the crane shall not use braided and extended steel wire rope.

11. The steel wire rope shall be scrapped under any of the following circumstances.

(1) The number of broken wires of steel wire rope at one pitch Table 3.

(2) The steel wire rope is worn or corroded to more than 40% of the original diameter, or the steel wire rope is severely annealed or burned by local arc.

(3) The rope core is damaged or the rope strand is squeezed.

(4) Cage deformity, severe distortion or bending.

(5) The steel wire rope is flat and deformed, and the surface burr is serious.

(6) The number of broken wires of steel wire rope is small, but the number of broken wires increases rapidly.

12. The scrapped steel wire rope shall be cut off and placed in the designated place, and shall not be thrown away at will, so as to avoid accidents caused by misuse.

13. The steel wire rope in operation shall not rub with other objects. Friction may cause damage, breakage or overloading of the wire rope.

14. When the steel wire rope is connected by splicing method, the number of insertion of steel wire rope with diameter less than 15mm shall not be less than 4 per share; The diameter of steel wire rope less than 15-28mm shall not be less than 5; The diameter of steel wire rope less than 28-60mm shall not be less than 6. The strength of the steel wire rope used to fix the rope end by the braiding method is 75% - 90% of the strength of the steel wire rope itself. It is important to consider the impact of this connection.

15. In order to ensure the safe use of steel wire rope, safety technical inspection must be carried out for steel wire rope. The tests are divided into the following three types.

(1) Daily inspection. Observe all visible parts of the steel wire rope every working day and find damage and deformation.

(2) Check regularly. Steel wire ropes used in special environments such as high temperature, corrosion and toxicity shall be inspected at least twice a week; The steel wire rope used by ordinary lifting machinery shall be inspected at least once a week; For long-term working wire rope, it shall be inspected at least once a month.

(3) Special inspection. In case of major natural disasters or accidents, as well as cranes that have been out of service for more than two months, they can continue to be used only after passing the special inspection.