Embedded problem of hook of civil air defense door
Ordinary steel bars are not allowed in the welding, flash welding head position to leave. Not to mention this kind of pull bar.To sum up, such an approach is not allowed.
Air door hook pre buried air raid garage can use two round steel inserted under the roof, then after stripping, the bending steel welded together, this approach can not. Must first be processed into U shape, and then once buried in place.
The hook is installed after the explosion door, you also can not, as long as the supervision and explosion-proof door manufacturers agree, but this is generally 22 round steel hook, then bending welding is removal of trouble ah, not processed the pre buried.
Then bending welding, make steel embrittlement, impact ductility, the bend is more
