The following Xiao Hao explained to you: fire-resistant cable is not flame-retardant cable, the principle difference?
Most people can easily confuse the concept of flame-retardant cables and fire-resistant cables. Although flame-retardant cables have many advantages that are more suitable for chemical companies, such as low-halogen, low-smoke and flame retardant, in general, fire-resistant cables can replace flame-retardant cables. Fire-retardant cables cannot replace fire-resistant cables. The main difference between them is:
The difference between principles
The principle of fire-resistant cable and flame-retardant cable is different. Halogen-containing cable flame retardant principle is based on the flame retardant effect of halogen, halogen-free cable flame retardant principle is to rely on the precipitation of water to lower the temperature to extinguish the fire roasted. Fire-resistant cable is based on the refractory and heat-resistant characteristics of the mica material in the fire-resistant layer to ensure the cable It also works fine in a fire.
Difference between structure and material
The structure and materials of fire-resistant cables are also different from those of flame-retardant cables. The basic structure of the flame-retardant cable is:
(1) Flame retardant material for insulation
(2) The flame retardant material is used for the sheath and outer sheath;
(3) Flame retardant materials are used for wrapping and filling.
The fire-resistant cable is usually an additional fire-resistant layer between the conductor and the insulating layer. Therefore, theoretically, a flame-retardant layer can be added to the structure of the flame-retardant cable to form a flame-retardant and fire-resistant cable. There is no need for this.
Because of the fire-resistant cable's fire-retardant layer, multi-layer mica tape is usually used to directly wrap around the wire. It can withstand long-term combustion, even if the polymer at the flame is burned, it can ensure the normal operation of the line.
Â
Flame-retardant cables, halogen-free cables, fire-resistant cables, clear concepts and advantages and disadvantages
Flame retardant cable is characterized by retarding the spread of flame along the cable so that the fire will not expand. Because of its low cost, it is a large variety of cables used in fire protection cables. Whether it is a single cable or a bundled cable, the cable can control the spread of the flame within a certain range when it is burned. Therefore, it is possible to avoid the major disaster caused by the flame propagation, thereby increasing the fire protection level of the cable line.
Halogen-free and low-smoke flame-retardant cables are characterized by not only good flame-retardant properties, but also halogen-free, low-smoke and halogen-free cable materials, which have low corrosiveness and toxicity when burned, and produce a very small amount of smoke, thus reducing the Damage to people, equipment, and equipment is conducive to timely rescue in the event of fire. Although it has good flame retardancy, corrosion resistance, and low smoke concentration, it is slightly inferior in mechanical and electrical performance to ordinary cables.
Fire-resistant cables are normally operated for a certain period of time in the event of a flame, maintaining the integrity of the line. The flame-retardant cable produces less sour fume when burned, and the fire-retardant flame-retardant performance is greatly improved. Especially when burning, along with the water spray and the mechanical blow, the cable can still maintain the complete operation of the line.
Carbon Steel Flux Core Wire
1. Flux cored Welding wire AWS A5.20 E71T-1 introduction: E71T-1 is a kind of TI type Flux Cored Wire for CO2 welding ,it has high cladding efficiency, good welding technical performance in all-position welding, apply for low carbon steel and 500MPA grade strength steel welding, such as ships, pressure vessels, mechanical equipment and bridges.
2. Application: Metallurgical industry, Bridge building, Building industry, Chemical industry, shipping industry
down-hand welding,vertical up ward welding and overhead position welding
It is suitable for all-position welding with excellent technological performance, stable arc, less splashing and beautiful weld form. the weld metal has good intergranular corrosion resistance and low crack sensitivity.