Discuss the environmental protection requirements of PVC wires and cables
Non-environmental cables are strictly prohibited in developed countries, and China also attaches great importance to this field. Relevant laws and regulations of our country explicitly require important buildings to prohibit the use of PVC wires and cables, and halogen-free and low-smoke crosslinked PVC wires and cables must be used to avoid a large amount of thick smoke and chlorine gas during fire, causing casualties. Environmental protection cable will effectively drive the development of cable industry, enhance the competitiveness of cable production enterprises, and make the cable industry more and more stable on the road of sustainable development in green practice and innovation. In recent years, China's cable enterprises have gradually made efforts towards environmental protection cables and low-smoke halogen-free cables, etc. , as far as possible to do not contain heavy metals such as lead, cadmium and mercury, and do not contain brominated flame retardants, no harmful halogen gas, no corrosive gas, less heat generation during combustion, no soil pollution, etc. , environmental protection cables will be more favored by the market, it is easier to obtain high orders in the bidding of power grid companies. The user's requirements for environmentally friendly wires and cables are summarized as follows: 1. The content of lead and heavy metals is required to be low. As we all know, lead and some heavy metals will have adverse effects on human health. In PVC formula, usually need to mix lead, cadmium, barium and other heavy metal compounds additives. However, since the 1990s, some developed countries and large electric companies have successively formulated regulations. In the PVC wires and cables used, the content of eight heavy metals shall not be greater than the regulations. These new regulations not only bring new business opportunities to wire and cable manufacturers, but also bring serious challenges to PVC cable manufacturers. 2. It is a very obvious advantage of PVC wires and cables to require good flame retardant properties of low smoke and low hydrogen oxide. However, when ordinary flame retardant PVC cables are on fire, it will release thick black smoke and a large amount of HCI gas, thus causing 'secondary disasters' after the fire, seriously affecting the evacuation of personnel and the development of fire rescue work. Therefore, while putting forward flame retardant requirements for wires and cables, the requirements of 'low smoke' and 'low hci' will be further put forward in some use occasions. 3. Requirements for low toxicity or non-toxicity for some household appliances that may come into contact with food and blood products, medical and health appliances and cables used on children's electric toys, in addition to requiring lead-free and heavy metal-free, non-toxic (Or low toxicity). This means that all ingredient materials used in PVC formulations should be non-toxic. Cable materials contain a large amount of plasticizers, but non-toxic plasticizers must be selected for the manufacture of non-toxic materials. Therefore, the requirement of this kind of PVC material is higher than that of lead-free and heavy metal-free materials, and the selling price is naturally more expensive. 4. At present, the regulations under trial in the EU restrict the following items to ensure that wires and cables can meet the requirements of environmental protection. For example: 1)Asbestos; 2)Polyphenyls and their ethers, polybromophenol; 3)Polychlorinated biphenyls; 4)Short chain (C10 ~ C13)Chlorinated paraffin. As more and more attention has been paid to environmental problems, many countries have formulated various environmental protection policies, so people are more inclined to use green cables. Low smoke halogen-free flame retardant cable material is one of the most popular environmental protection cables at present. Although the demand for green environmental protection cables in our country's market is growing day by day, compared with developed countries, our country still has a long way to go in terms of relevant policy formulation and mandatory application, china should improve the environmental protection cable standards as soon as possible.