The size of the joint of the steel fireproof door is clearly specified: the big sister of the door leaf and the door frame shall not be less than 10mm, and the gap between the door leaf and the door frame shall not exceed 4mm. If the gap of the steel fire door is too large, it is difficult to ensure the sealing, and the fire door without sealing will lose the function of restraining fire and smoke spread.

Ọnụ ụzọ ọkụ ZHTdoors, afọ 31 nke mmepụta ihe na ọnụ ụzọ ọkụ na Windows. The isi UL ọkụ ọnụ ụzọ, EN ọkụ ọnụ ụzọ, BS EN ọkụ ọnụ ụzọ, wdg,..We nwere certification.ZHTdoors support OEM na free design.Our uru: Good quality, factory price, good service.Welcome to consult us.