First, considerable potential for natural gas development, large demand for olefin valves Natural gas is a very promising high quality clean energy. Natural gas almost no smoke and sulfur dioxide emissions in the combustion process, carbon dioxide thanks to the amount is also much smaller than the burning of coal oil. With the emphasis on the environment and the sustainable development of ecology in our country's urban areas and the improvement of people's living standards, it is estimated that the proportion of natural gas in China's urban gas will increase from the current 33% to 66% by 2010. There are three gas-bearing areas in Sichuan, Shaanxi-Gansu-Ningxia and Xinjiang in China. In addition, there are good oil and gas displays in the western South China Sea, the Yinggehai Basin and the East China Sea. Coupled with the introduction of Russian natural gas in the future, the import of liquefied natural gas in the Yangtze River and Pearl River Delta regions, the supply of natural gas in our country will be guaranteed. The construction and planning of "West-East Gas Pipeline" and "Russian Gas Supply" will enable the cities and towns along the pipeline to be gasified. Among them, the demand for gas pipeline valves is very large, and as a valve manufacturer, there is a lot of work to be done. The "West-East Gas Pipeline Project" is to transport natural gas east of Lunar in Tarim. The pipeline is exported from the first battle of South Rotterdam in Korla. It passes through Baihe Town, where eight provinces of Xinjiang, Gansu, Ningxia, Shaanxi, Shanxi, Henan, Anhui and Jiangsu end to Shanghai. Pipeline full-length 4200Km, pipe 1016mm, gas pressure 10MPa, is expected by the end of 2004 across the board. In addition to the demand of Sichuan Province, the Sichuan-Chongqing natural gas in Sichuan Basin is not completely transported by the East East from Zhongxian via Hubei to Wuhan City, then Xinyang and Tarim Natural Gas to the east of Henan Province converge to the east of Shanghai with a total length of 811km and is planned to be completed in 2003 . The Changqing gas field in Shaanxi, Gansu and Ningxia has completed construction to the surrounding area of ​​the gas field by the end of 1998 and has now completed four natural gas transmission pipelines: 1, Jing-service military personnel to Xi'an, Baoji and Tongchuan; 2, Jingbian to Ningxia and Yinchuan; 3 , Jingbian to Beijing's long-distance pipeline, plans to extend eastward from Beijing to Shandong; 4, Jingbian to Yulin, Qingyu County. The "Russian Gas Supply South" will be carried out in line with the feasibility study agreement signed by China, Russia and the ROK on November 2, 2000 and plans to be completed in 2007 in Beijing, Tianjin and Hebei in the three northeastern provinces and the Bohai Rim region Province, Shandong Province and other provinces and cities. Introduction to Gas Supply System - Gas Transmission System and Gas Distribution System Natural gas is generally supplied to users through pipelines. At present, natural gas pipelines in many countries are criss-crossing with perfect facilities and construction activities of trans-national gas pipelines are exceptionally active. As mentioned earlier, the construction of gas pipelines in our country has two kinds of flexible supply modes, such as LNG transportation and compressed natural gas vehicles. The supply of natural gas in cities and towns generally takes pipeline from the gas pipeline to the gate station and has the functions of metering, pressure regulation and odor addition (some of them are stored), and the pipeline and gas distribution system with different pressure levels in the urban area Generally, the low-pressure or medium-pressure class B gas supplied by the medium-pressure dry pipe to the user's pressure regulating station (box) is used for civil or boiler room and industrial users. The design pressure of urban gas pipelines is divided into seven levels: High-pressure gas pipelines A 2.5 Secondary high pressure gas pipeline A 0.8 Medium pressure gas pipeline A 0.2 Low pressure gas pipeline P <0.01MPa This article describes only the gas distribution system, gas design pressure 0.4MPa, selection of the valve pressure up to 1.6MPa. Third, the gas distribution system with the valve requirements Valve installation location and use of places: gas pipeline pressure in the underground valve room, the front of the pressure regulator device in the low-pressure or medium pressure B-level entrance of each user set the main valve, points Section of the valve, each household and then burning the total or cooker pipe upload control valve, the total pressure regulator, the gauge should be installed before and after the valve. Gas distribution system generally use manual valves, commonly used ball valves, butterfly valves, gate valves, oil seal plug valves. Medium voltage A cast iron valve below the use of more in recent years, began to use vinyl chloride vinyl chloride valve, because buried in the need to build valve room, has been widely used. Indoor pipe generally made of cast iron plug or copper ball valve, ball valve. Gas professional requirements of the valve is relatively high, to have tightness without leakage, no internal leakage, reasonable structure, safe operation, convenient, and a defensive fire performance, in case of fire does not leak for some time. China's indoor pipeline valve product quality is good, close to the technical level of similar foreign products. However, to adapt to different indoor needs, with the new pipe valve varieties to be broadened. Gas pipe valve compared with similar products, the main difference is greater than the valve material, processing technology, product performance and so on. Gas pipe network valves should be based on the type of gas and pressure level selection of ball valves, butterfly valves, plug valves and special gate valves. Liquefied petroleum gas system should use oil-specific valve. In order to reduce the gas regulator box (station), measuring the size between the selection of high quality butterfly valve (three eccentric, zero friction, zero leakage, metal seal). More Keywords Search: Valve