Application of Cable Trench Plugging Device in Metro Cable

　　 The subway is a convenient means of urban public transportation with a large passenger flow and little impact on the climate. A complete subway network has been built in major cities in the world, and subway construction in major cities in China is also in the ascendant. It is foreseeable that, in the near future, the subway will become an irreplaceable part of the public transportation system of major cities in China. However, we must clearly realize that since most subway lines are located in relatively closed underground spaces and densely populated places, it is difficult to escape and rescue in the event of a disaster. Among all possible disasters, fires are frequent and harmful. Once a fire occurs in an underground station, it will be filled with smoke and spread rapidly along the tunnel, causing serious disasters. Therefore, the cable trench blocking device is very important for subway applications.

　　 The main cause of subway fires is usually electricity. A large number of cables and wires are densely distributed in the subway, and they are often in a long-term high-load continuous operation state, which will cause overload and heat; the humid environment of the subway will aggravate the corrosion of cables and wire joints; the cable trench blocking device, and the frequent vibration of subway vehicles , It will also cause the cable and wire joints to become loose; all these will cause the cable and wire to short circuit and fire. Therefore, in addition to strengthening the subway's fire monitoring, alarm and fire extinguishing system, it is also very important and necessary to choose flame-retardant cables and wires, and to strengthen the cable trench blocking devices in the subway electromechanical system.

　　The particularity and material selection of the plugging device for subway cable trench:

　　 The subway project is very different from other public buildings, so it has its particularity in terms of subway fire protection and sealing.

　　 1. Due to the airtightness of the subway, the selected cable trench sealing device material must have the characteristics of low smoke and low toxicity. Traditional leak-stopping materials commonly used in the market, such as fire-resistant mud, contain a large amount of chlorinated paraffin, and many flame-retardant products also contain halogen elements. Although they can play a flame-retardant effect, they will produce a lot of irritating smoke poisons at high temperatures, which can suffocate people and cause secondary harm.

　　2. Due to the frequent vibrations caused by subway vehicles passing by, some fireproof sealing materials such as fireproof bags will be damaged, collapsed and fall off, resulting in lax sealing and losing the fireproof effect. Cable trench blocking device

　　3. Due to the long-term operation of electrical appliances and the enclosed environment, the local temperature of the electromechanical control room will be higher, which will easily lead to the softening and rheology of fireproof mud or some fireproof sealants. Loss of fire prevention effect. Cable trench blocking device

　　4. Because the subway is located in an underground environment with relatively high relative humidity, some inorganic blocking materials, such as mineral wool and fireproof coating panels based on it, are easy to absorb moisture and decompose by weathering.

　　 5. Since all fire blocking materials are concealed projects, once they are put into use, it is difficult to repair and maintain. Therefore, the fire blocking materials are required to have stable performance, high structural strength and long service life. However, traditional products such as mineral wool, fireproof bags and fireproof mud cannot meet these requirements. Cable trench blocking device

　　 6. A large number of cables pass through a subway tunnel similar to a cable tunnel. According to relevant national regulations, fire compartments should be set every 100 or 200 meters, especially at cable joints. However, because traditional materials are difficult to solve in terms of technical performance and construction technology, the absence of a cable trench blocking device for fire protection will leave hidden dangers of cable spreading and burning.

　　 In summary, the subway is a special project, and its cable trench plugging device should be taken seriously like an active fire protection system to ensure subway safety.