Why does the chain of hand-pulled gourd break?

　　1. Improper operation, not in accordance with the instructions of the operation method, in the operation of invisible damage, a long time will fracture.

　　2. Overloading, not hoisting according to the load on the label, increases the bearing capacity of the chain and leads to chain fracture.

　　3. Fail to carry out maintenance, fail to grease the chain in time, and rust and crack the chain for a long time.

　　4. The new chain is used together with the old chain, resulting in impact force in the process of operation, and it is easy to break the chain.