Strength calculation of load bearing safety of 300T crane hook blocks set:
According to the acceptance analysis of the loading status of the hook according to the plane elastic curve theory, the dangerous sections of the hook are mainly in three parts: horizontal section a-a, vertical section b-b and the root of the thread of the hook handle c-c.
The hook state near the dangerous section is the key point of safety inspection.
(1) c-c section of the tail of the hook handle
Stress concentration in the root of the thread will also be subject to corrosion and easy to break in the defect.
(2) vertical b-b profile of the hook body:
Although the force is not as big as a-a cross section, it is the part of heavy wear of the sling. As the cross section area decreases, the carrying capacity gradually decreases.
In operation, attention should be paid to the Angle between the branches of the sling to control the fastener.
(3) hook body level A - A section
The effect of lifting load on a-a section is eccentric tension, so the section is subjected to the combined stress of bending and stretching.
The stress on the inner side of the cross section is large tensile stress, while the outer side of the cross section is large compressive stress.