Prospects and current status of China's natural gas industry
With China's rapid economic growth in the long-term energy needs, the people on the quality of life and ecological environment of rising demands. West-Sichuan-East Gas Transmission, as well as the introduction of Russian natural gas, natural gas project of the century shows that a high-quality, clean and environmentally friendly features such as an important energy source, is ever by my Government attaches great importance to. China Gas in the West-East and the Sichuan Gas to East to send along the 10 provinces have set up 46 franchises owned natural gas joint venture investment more than 50 natural gas pipeline network project, and this figure will be with China Gas The rapid expansion of the market continuously increasing.
West-East Gas Project smooth implementation of the enhanced level of China's natural gas pipeline network construction, in order to form a national natural gas pipeline network laid the foundation. To West-East Gas Project as a starting point, the level of China's natural gas pipeline construction to the international advanced level gradually move closer toward the long-distance, large-caliber, high-pressure and highly automated network management direction for the rapid development of China's natural gas industry has laid a solid material foundation.
West-projects have been built and opened one of China's east-west artery of energy, for developing the western region and accelerate the development of central and western regions, Xinjiang and along the benefit of the masses of all ethnic groups, for promoting industrial restructuring and energy structure optimization, the protection of national energy security, will play a major role. West-west Xinjiang round of the South, passing through 10 provinces, autonomous regions and municipalities, total length of about 4,000 kilometers, designed annual gas transmission capacity 12 billion cubic meters. Transmission projects are under way by 170 billion cubic meters. Middle and lower reaches will be built Liu Chuang-tzu, Jintan two large underground gas storage. Pipeline Project through the Gobi desert, the Loess Plateau, the Taihang Mountains, crossing the Yellow River, Huaihe River, Yangtze River, is currently China's largest diameter, wall thick, pressure rating the highest, the most difficult technical pipeline project to create a number of domestic gas pipelines leading record, but also created the history of the world's high-speed pipeline construction. West-East Gas Project marks the completion and operation of the overall level of China's natural gas pipeline construction on a new level, laying the foundation for China's natural gas pipe network.
It is understood that China's West-East Gas Project construction will be an opportunity to co-ordinate the east central and western China, at sea and onshore natural gas resources, and actively implement the "going global" strategy, the introduction of foreign natural gas resources, to further improve China's natural gas pipeline network development plan, to speed up trunk pipelines, gas storage, booster stations and related extension of the building, covering the whole country to build two vertical and five horizontal backbone gas pipeline network, and gradually form a natural gas and gas south to the north, close to foreign supply, gas supply, air-sea landing pattern of the final round of the south to form a Shanghai Changqing Route to Beijing-based natural gas and Shaanxi-Beijing line and the second Shaanxi-Beijing, as well as Sichuan, Chongqing, Tianjin and Hebei Lu Jin, Yangtze River Delta, Northwest, Hunan and Hubei region Lord's regional natural gas pipeline network and ultimately a national natural gas resources, diversification of supply networks and market scale.
Characteristics of natural gas pipeline valves
With the gas pipeline industry, gas pipeline increasing amount of the valve, gas pipeline valves and normal valves are different. Specifically include the following:
(1), material
Because of pipeline transportation of natural gas desulfurization ago contains a lot of hydrogen sulfide (which is a highly toxic and corrosive gas, it is the reaction of iron sulfide and iron can be exfoliated was wearing corrosion mechanical equipment). Process even after the desulfurization of natural gas, there are still remnants of hydrogen sulphide. Therefore, selection must be selected pipeline valve corrosion resistance to sulfur material.
(2), leakage
Most natural gas pipe network built on the city's edge, unlike the general operation and management of factories, workers often have to operate, maintenance and inspection. Average city in the natural gas pipeline are hundreds of kilometers or more, only regular patrols, inspection, and sometimes complicated pipeline through the region, media leaks could result in serious fire incidents. In particular, away from the city closer to the pipeline, to prevent the leakage of the valve is particularly important.
Leakage of natural gas valve very strict, often buried and more important body of the valve have adopted all-welded structure. In order to ensure the pipeline of the valve sealing performance require Sealing excellent corrosion resistance, wear resistance, self-lubrication and flexibility. In recent years, the development of polymer materials for the pipeline valve seal material selection provides a broad selection Heaven and Earth, such as Teflon, nylon, acrylonitrile-butadiene rubber (NBR), a special synthetic rubber (VITON) and so on.
(3), applications
Pipeline, once operational, are not allowed to stop within a few years running, the longer run is good, unlike most chemical plants or refineries, there are overhaul period. Pipeline transportation of natural gas facing the city's large number of users, and some residents, businesses, factories, especially on natural gas as raw material of business users, not allowed to have a moment interrupted. Series in the pipeline on the pipeline valve failure, lead to disastrous consequences. Therefore, the main pipeline valve seals and other wearing parts such as seat parts will require long life. The general life of the main trunk pipeline valves require more than 30 years.
(4), drive unit
As the high pressure transmission pipeline, diameter large, fast switching time, pipeline valves need to adopt high-torque drive. Such as electric or pneumatic devices, gas - liquid interaction or electric - hydraulic interlocks. Drives also need explosion-proof requirements, requirements EExdIIBT4, protection grade IP68. A result of management control officers generally in the station or central control room, thus requiring the event of pipeline rupture and other major incidents, pipeline valve can automatically cut off. Pipeline valve operating force required is small, the temperature outside changes have an impact, they can achieve accurate operation. Especially in emergency shut-off valve must be able to long period of full-state, if necessary, quickly locking pipe. Meanwhile, the required valve opening and closing the location and opening position indicator accurate, easy to understand and meet the appropriate switching speed.
本文转自：China Industry News
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