Since the late 1970s, with the development of economy and the frequent occurrence of electrical fire accidents, attention has been paid to the development and use of flame retardant cables. Many wire and cable users have put forward new requirements for the flame retardant properties of products.

Rubber and plastic polymers are the main materials for the manufacture of wire and cable insulation and sheathing, and most of them are easy to burn and delay burning. With the continuous increase in the amount of wire and cable and the frequent occurrence of electrical fire accidents, the flame retardant problem of wire and cable materials has gradually attracted the attention of all countries in the world. As early as the 1970s, flame-retardant cables have been developed at home and abroad, but these flame-retardant cables are almost all halogen-containing. Although they have a certain flame-retardant effect, when a fire occurs, the burning wires and cables still produce toxic gases. and smog, which not only affects the smooth progress of disaster relief work, but also causes a "second disaster" to life and property. As many industrial sectors, subways, high-rise buildings and other municipal and civil facilities have higher and higher requirements for safety and reliability, it is urgent to develop a new generation of low-smoke halogen-free flame-retardant cables.

                                                        

Advantages of Soft Grade Low Smoke Halogen Free Flame Retardant Polyolefin Sheath Materials
Low-smoke halogen-free flame-retardant cables are also known as "clean cables" abroad. It is different from Pva cables and ordinary flame-retardant cables for the purpose of preventing flame retardation. It uses polyolefin resin without chlorine, fluorine and other halides as the cable material. New flame retardant cable with low toxicity. SHRD-H-01 is based on polyolefin, contains special halogen-free flame retardant and smoke suppressant, and is processed by precise mixing with special formula. Its flame retardant system has excellent flame retardancy, no halogen acid gas is released during combustion, very little toxic and corrosive gas is released, and the generated smoke concentration is extremely low. And the delivery speed is fast and the surface is smooth.

Characteristics and application of soft-grade low-smoke halogen-free flame retardant polyolefin sheath material
This product not only has excellent low-smoke halogen-free flame retardant properties, but also has good extrusion processing performance, fast extrusion speed and smooth surface. It can be extruded on an ordinary PVC extruder. As long as the cooling device is normal, the extrusion processing speed can be accelerated. This product is suitable for occasions with high flame retardancy and low secondary hazards, and is suitable for low-smoke halogen-free flame-retardant sheaths of flexible optical cables and flexible data cables.

Extrusion production process
If the aluminum-plastic conforms to the moisture-proof failure of the inner bag, it must be dried before use, and the blasting method should be used. The drying temperature is 65 °C and the drying time is at least 2 hours. It can be extruded by L/D18-25 extruder. When the screw compression is relatively low, the output is larger. Each zone of the extruder must have a cooling control system, and the melt temperature should not exceed 170 °C. Since the difference between the actual temperature of the melt and the indicated value of the temperature control table varies with the type of extruder, each user should select a suitable temperature according to the specific conditions of the extruder used.

                      

Cable Requirements
1. Hard to have the same practical performance as the current general flame retardant cable;
2. The structure of the cable is different from that of the general cable, that is, a flame retardant isolation tape or a special polyolefin material should be used.