Fire-proof roll-curtain doors are widely used in fire doors. The development trend of electric roll-curtain doors is from sheet-type fire-proof roll-curtain doors to double-sheet composite and double-track double-curtain inorganic fabric, so as to integrate into stronger fire safety regulations. Major fire-proof doors and windows manufacturers are in the process of continuous scientific research and exploration.
In the early stage, the steel fire-proof rolling shutter door was double-plate type, and its curtain surface was usually made of 0.5-1.5mm thick cold-rolled steel sheet cut and cold-rolled strip curtain. Double-plate steel fire-proof rolling curtain door mask has the advantages of simple structure, high compressive strength, air pressure resistance, anti-theft, good plasticity, easy processing, installation and use, but its fire resistance and heat insulation performance are poor. The poor fire resistance is due to the decrease in strength of steel at high temperatures. For example, the strength of ordinary low carbon steel begins to decrease rapidly when the temperature exceeds 350 C. The strength is about 1/2 of normal temperature at 500 C and 1/3 of normal temperature at 600 C. In addition, the stainless steel sheet will produce plastic deformation with the passage of time under the necessary temperature and in-situ stress. The stainless steel sheet will produce creep at ultra-low temperature, which is significant at high temperature. For example, the creep of high carbon steel is obvious at 300-350 (?) and 400-450 (?) C, which can easily cause deformation and reduce the fire safety characteristics. The poor thermal insulation performance of steel is due to the fact that steel is a good conductor of heat and has a high thermal conductivity. According to combustion theory and thermal principle, combustion, heat transfer and temperature rise are interrelated, interacting and inseparable physical phenomena. Because the fireproof performance of double-plate steel fire-proof roll curtain door curtain is poor, when a fire accident occurs, the maximum heat generated in a moment in the building is transferred from the fire surface to the back surface according to heat conduction, radiation, convective heat and other methods, so that the temperature of the back surface rises sharply. When the back fire temperature rises to the ignition point of some combustibles, the fire resistance of the fire-proof roll curtain will be greatly reduced or even lost.
Composite steel fire-proof roll-curtain doors are widely used in China at present. Compared with double-plate steel fire-proof roll-curtain doors, the improved structure not only preserves the advantages of double-plate steel fire-proof roll-curtain doors, but also significantly improves the fire resistance. In terms of curtain structure, the composite steel fire-proof roll curtain is composed of two thin steel strips and a layer of inorganic fiber insulation material. At present, the inorganic fiber insulation materials used by various manufacturers mainly include rock wool, mineral wool, glass wool or aluminium silicate fibers. Because of the small thermal conductivity of inorganic fibers, the thermal insulation performance of composite steel fire-proof roll curtain is better than that of single-board steel fire-proof roll curtain. However, as can be seen from table 1, the maximum temperature of rock wool, mineral wool and glass wool fibers is lower than 924 C of the international standard temperature curve for one hour. If the thermal insulation of the steel plate is not considered, theoretically, unless there is enough thickness, the three materials can not meet the fire resistance limit of the fire-proof roll curtain (> 3 hours) in the High Regulations. In fact, due to the restriction of composite steel curtain structure, the inorganic fiber layer of composite steel fireproof curtain is not more than 20 mm and is not a continuous layer. This thickness can not guarantee the fireproof limit of fireproof curtain (> 3 hours) and the temperature rise of backfire surface (> 140 C). For aluminium silicate fibers, the single layer thickness (<20mm) can="" not="" meet="" the="" condition="" of="" fire="" resistance="" limit="">3 hours), although the high temperature resistance is above 1200 C. Therefore, although the performance of composite steel fire-proof roll curtain is obviously improved than that of single-plate steel fire-proof roll curtain, it still can not overcome the main defects of single-plate steel fire-proof roll curtain and can not meet the requirements of the new standard of "High Regulations".
At the present stage, the special inorganic double-track fire-proof roll-curtain door with double curtain is light and does not deform when it meets high temperature. It has obvious advantages in fire-resistant grade, noise, thermal radiation, large hole edge and other selected index values. The surface is corrosion-resistant and corrosion-resistant, and its service life is longer. Its unique characteristics overcome the steel fire-proof roll. The drawbacks of curtain doors have been widely used. Extensive application.