1. Human-driven lifting mechanism for hoisting hook, with 1.5 times times rated load as test load test.
2. Power-driven hoisting mechanism used in the lifting hook, twice times the rated load as a test load tests.
3. After unloading the hook to test the load, there should be no obvious defects and deformation, the increase in the opening degree should not exceed 0.25% of the original size.
4. The inspection of the hook, should be in the low stress area of the hook printing mark, including the rated weight, plant or factory name, inspection signs, production numbers and so on.