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    Three points to pay attention to when purchasing fire doors
    Date: 2019/12/27 Publisher: 草莓IOS在线观看工贸 Hits: 2125
    Steel fire doors and wood fire doors can be divided into three types according to the fire resistance limit: Class A, class B and class C. The fire resistance requirements of the former are 72min, 54min and 36min respectively, and the fire resistance requirements of the latter are 72min, 54min and 36min respectively. Moreover, the wood used to make wood fire doors need to be dried and flame retardant, and its moisture content shall not be greater than 12%.
    In addition, the hardware fittings used for wooden fire doors must be fire hardware fittings, mainly including: Fire hinge, fire bolt, fire door lock, fire sequencer and fire door closer.
    Note 1: check the appearance
    High quality steel fireproof doors shall be firmly welded with uniform distribution of welding points; the external surface shall be painted flat and smooth; product mark, quality inspection mark and quality certification (APPROVAL) mark shall be provided at the specified position. It seems that the unqualified products are not welded firmly and the distribution of welding points is uneven; the spraying is not smooth and smooth; there is no product mark, quality inspection mark and quality certification (APPROVAL) mark at the specified position.
    The qualified wooden fireproof door shall be complete without damage, with clean surface, no planed mark, burr and hammer mark; the corner cutting and seam splicing shall be tight and flat; the product mark, quality inspection mark and quality certification (APPROVAL) mark shall be provided at the specified position. The appearance of unqualified products is incomplete, damaged, the surface is not clean, there are planed marks, burrs and hammer marks; the corner cutting and joint are not tight and flat; there is no product mark, quality inspection mark and quality certification (APPROVAL) mark at the specified position.
    Note 2: right numbers
    The overall dimension of qualified products shall be ≤ the overall dimension in the sample description, the door leaf thickness shall be ≥ the door leaf thickness in the sample description, the door frame side wall width shall be ≥ the door frame side wall width in the sample description, the overall dimension of fireproof glass shall be ≤ the overall dimension of fireproof glass in the sample description, and the thickness of fireproof glass shall be ≥ the fireproof glass thickness in the sample description.
    The boundary dimension of the unqualified products shall be > that in the sample description, the thickness of the door leaf shall be < that in the sample description, the width of the side wall of the door frame shall be < that in the sample description, the boundary dimension of the fireproof glass shall be > that in the sample description, and the thickness of the fireproof glass shall be < that in the sample description.
    Note 3: look at the seal
    The qualified steel fire doors and wooden fire doors shall be provided with fire sealing strips, which shall be straight and free of arching, and shall have the qualified test report issued by the national testing agency; the unqualified products shall not be provided with fire sealing strips, or the sealing strips shall not be straight and free of arching, and shall not have the qualified test report issued by the national testing agency.
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