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        How to identify the quality of steel fire doors

        2019-10-28 2255

        We can identify the poor quality of steel doors when we buy them. As a low-cost and convenient fireproof partition, steel fireproof glass door has played a very important role in preventing the spread of fire and smoke and ensuring the dispersion of personnel. In the field of construction engineering and application, the following quality problems often occur:

        I. The fire resistance integrity of steel fireproof glass door is poor. Some enterprises take the road of low-cost and defective products in daily production. The products are shoddy or the quality control in the device link is not strict, resulting in serious overspending of various gap widths such as door leaf, mouth seam, frame leaf seam, door leaf and ground seam, which can not meet the technical requirements of the standard rules due to fire leakage during inspection. In the actual project, some steel fire doors are not equipped with door closers, sequencers and sealing strips, which seriously affects the fire and smoke separation function of steel fire-proof glass doors and should be found in time.

        防火玻璃門

        II. Some steel fireproof glass doors use inappropriate sealing materials to hinder the opening and closing of the door leaf. The design gap between the door frame and the door leaf is too small, and the quality of the door closer is too poor, resulting in too large opening force and reaction force, which will affect the opening and closing of the fireproof door. During inspection, the problem can be found only by on-site operation and opening and closing the fire door several times.

        III. poor thermal insulation of door leaf. The filling material of steel fireproof glass door is generally aluminum silicate fiber or rock wool. The fire resistance of aluminum silicate fiber is significantly better than rock wool, but the price is higher. In the field of application, attention should be paid to the phenomenon that many manufacturers use cheap rock wool to replace the aluminum silicate fiber actually used in type inspection. If the glass area is too large, it is generally difficult for the door leaf as a whole to meet the requirements of fire integrity and heat insulation. When checking, you can actually measure the glass area and thickness, whether it is fireproof glass, etc.

        The good or bad quality of steel fireproof glass door directly affects the improper treatment of the gap between thermal insulation materials, resulting in poor thermal insulation of the door leaf.

        Fire door http://m.wan-xin.net/


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