Double beam crane can produce thermal stress
The welding quality of the butt welds of the steel plate of the double beam crane can completely avoid the problems caused by the welding cause, and the operator can be very safe to operate.
The welding technology of the butt weld of the main beam of the double beam crane is more complicated, and it is easy to appear the defects such as non penetration, inclusion, air hole, hot crack and cold crack, especially the thermal stress produced by the butt weld, which will endanger the micro gap of the edge of the base of the welded joint, such as dispersion inclusion and intergranular structure. Uniform and so on. These micro defects will expand under the effect of welding heat, causing strong thermal stress at the joint of the weld and the base material. When the stress reaches the stress that the material cannot bear, the steel plate and the weld will produce macroscopic cracks or delayed cracks. Therefore, the non-destructive testing of the main beam of the double beam crane is to ensure the quality of the main beam. And one of the important links to use security.
The use of double beam crane must be properly protected, do not use them arbitrarily, this will cause serious consequences.