5.3　Chain Block

5.3.1　Prior to use，the following items of chain block shall be inspected:

a）Rotating parts for free movement without any seizure；

b）Chains for intactness and pins for firmness；

c）Brake for proper function.

5.3.2　Electric chain block shall be equipped with overload alarm and overload limit device.

5.3.3　If the brake band lining of an electric chain block experiences an abrasion up to 50% of its original thickness or exceeding the maximum allowable adjustment value for the motor shaft，it shall be replaced with a new one.

5.3.4　When chain block is in service，its chain shall be put in order，and the forces carried by two hooks shall be controlled in the same axis.

5.3.5　Chain block shall be operated in a clean environment to prevent foreign matters from entering the rotating parts.

5.3.6　When hand chain block is released，its load chain shall have at least 3 buckles retainable.

5.3.7　Hand chain block shall not be put into service unless it is checked and confirmed by pulling-in gradually.

5.3.8　The bearing capacity of the hanging point of a hand chain block shall not be less than 1.05 times the rated capacity of such hand chain block.

5.3.9　Where multiple chain blocks are used to lift one workpiece，they shall be operated simultaneously，and the maximum load for each chain block shall not exceed 70% of its rated capacity.