Before leaving the factory, hand pulled hoists undergo a very important tensile testing process, which is similar to the breaking tensile test of steel wire ropes. The purpose is to measure whether the rated load and corresponding safety factor of the entire hand pulled hoist are qualified.

Of course, it is good to test only one chain hoist in the same batch of products, because the entire test result is basically that the original chain hoist is scrapped, so it is impossible to test all chain hoists once, as it would be meaningless.

The tensile test of a typical chain hoist involves applying a force of about 4 times the rated load, and then continuously observing the strength curve changes of the chain hoist during this period, which is the lower limit of the breaking force. When the tension is continuously increased on the basis of this tension until the chain hoist is completely scrapped, this belongs to the upper limit of the breaking force of the chain hoist, that is, the ultimate bearing capacity.

Hand pulled hoists observe and record changes in numerical values in this way, in order to determine whether the hoist is qualified at rated load and safety factor. Only after ensuring accuracy can it leave the factory.