In many places of key projects, such as fire control, monitoring, alarm, and so on, low smoke and halogen free wire and cable will be used.
In fact, the environmental cable does not refer to the low smoke and halogen free wire and cable, but the cable made according to the standard of the Japanese FN cable!!!
With the promotion and spread of the concept of green environment in the world, the concept of environmental protection is gradually infiltrating into all walks of life. With the gradual use of environmentally friendly products and the popularity of the people, the wire and cable industry has begun to attach importance to the development and popularization of environmental cables.
China also attaches great importance to this field, and the relevant laws and regulations require that non environmental cables are strictly prohibited in the construction of major projects.
The concept of environmental cable
The concept of environment-friendly cables has been confused. 10 years ago, low smoke and halogen free cables began to be applied. Japanese call it "clean cable", "green cable", "pollution-free cable", "environment-friendly cable", and "green ecological cable" (ECO). In fact, the concept of low smoke halogen free cable is only based on PVC cable, which is confined to "smoke" and "halogen", while "halogen" is only limited to HCl gas, and halogen compound HF (hydrogen fluoride) gas generated by fluoroplastics is more toxic. It is not comprehensive and inappropriate to simply say low smoke non halogen cables as environmentally friendly cables. The key of environmental protection cable is whether it can meet the environment requirements such as air, water, soil and so on. In addition to the toxicity of tobacco and halogen, there are heavy metals and other harmful substances, as well as the reclaim and treatment requirements. Therefore, when the cable product is named as environmental cable, it should be taken into consideration from the aspects of smoke, halogen, heavy metal and recovery.
Basic performance of environmental cable
Flame-retardant and no halogen. Reducing the amount of halogen-containing, in fact, is to reduce the original flame retardancy of PVC, and to maintain a certain flame retardancy, it is necessary to add flame retardant. The content of chlorine in PVC resin is about 57%, and the content of chlorine is 25 - 35%, even in the PVC material containing the coordination agent. When PVC is burned with bromine - based flame retardants, the dehydrogenation reaction occurs and HCl is generated. HCl is a very corrosive acidic substance. It not only stimulates human respiratory tract mucosa, but also suffocates people just like CO. At the same time, it also pollute the surrounding instruments and metal utensils, pollute the atmospheric environment, cause acid rain, and form two disasters. At the same time, the aliphatic, aromatic and chlorinated hydrocarbons containing halogen are produced under the condition of incomplete combustion, which contains the carcinogen dioxin. Phosphorous flame retardants not only produce acid corrosive substances and smoke and dust when burning, but also cause the eutrophication of water resources after the combustion residues enter the water system, resulting in a large number of algae and fish and so on. Therefore, it is an important issue how to balance the flame retardancy and not contain halogen, so that it fully meets the requirements of environmental protection.
No heavy metals. It is to restrict the use of some heavy metals, such as the lead salt can not be used in the cable sheath. The exudates of the cable sheath penetrate into the soil and are absorbed by the crops. People will be poisoned after eating. Heavy metals such as lead, cadmium, six valent chromium will pollute the soil, and polybrominated biphenyls and polybrominated diphenyl ethers will produce dioxins, which will pollute the atmosphere. In the IEC60502 standard, the harmful substances which are forbidden to be used have been clearly defined. The heavy metal lead, cadmium and chromium in the PVC cable material are mainly in the flame retardant, stabilizer, plasticizer, pigment, filler and lubricant. Stabilizers, plasticizers and pigments are the main hazards to human health and the environment. If these additives are used in other plastic materials, it can also cause serious environmental pollution.
So, what are the features of the environmental cable?
1, high flame retardancy
The environmental protection cable can completely guarantee its high requirement for fire protection. When the fire happens, the environmental protection cable can not only burn easily, but also prevent the spread of fire and the expansion of the disaster.
2, halogen free
The green jacket insulation layer, and a special oxygen barrier layer material, not only the environmental protection cable has good electrical properties, mechanical properties, and ensure that the product does not contain halogen, solves its combustion to form a "two pollution", to avoid the traditional PVC cause AI wire burning when the "Er evil the British" material.
3, low toxin
The environmental protection cable's insulation and sheath contain no heavy metals such as lead and cadmium, which will pollute the soil and water sources when the environmental cables are used or disposed. And after a severe toxicity test, the mice were safe and sound under the prescribed experimental conditions.
4. No corrosion gas is produced
The new special coating material and has no pollution to the environment, so that environmental protection HCL cable and other toxic gases can not be generated in the production, use and process of combustion, emissions of acid gas, the personnel and equipment damage, more environmental protection feature.
5. High transmittance
The smoke produced by the environmental protection cable is very thin, which is beneficial to the evacuation and fire fighting. Generally speaking, the transmittance of environmental cable products is more than 40%, which is far higher than the standard of less than 20% of the traditional type of flame retardant cable cable transmission.
6, high protection of ultraviolet or water
This performance can make environmental cables less easy to be weathered in use, to a certain extent, to slow down the aging of environmental cables and prolong their service life.
In general, environmental cable is a big trend. In recent years, the sales share of environmental cable products