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Gas valves occupy an important position in the gas industry. Ministry of Construction attaches great importance to the normative construction of gas valves, gas valve industry standards CJ3005-1992 "town gas gray iron valve with the general technical requirements," CJ3055-1995 "urban gas valves with the test," CJ3056- -1995 "General Technical Specifications for Ductile Iron and Cast Steel Valves for Gas in Cities and Towns", adopted the industry standard "Household Manual Gas Valves" in June 2002. The formulation and promulgation of these standards have regulated the valve industry, promoted the progress and development of gas valves and promoted the development of gas utilities, provided references for the development, production and use of units; and improved the distinction between gas valves and general valves , To ensure the safety margin gas valve; by the gas colleagues are welcome. First, the RX series of oil-sealed cock In the eighties of last century, China's gas is mainly artificial coal gas; artificial coal gas has more impurities and "gas glue", the original single-decker used conventional water Gate valve is increasingly unable to meet the needs of gas conditions, the prevalence of such valves, "the valve is not strict" and the valve stem biting problem, we developed by reference to Japan's technology developed RX series of gas oil sealing plug valves, to solve Tightness and valve stem biting problem. Second, RZ series of gas with two parallel gate valve With the development of gas and gas plant have set up, need larger or even larger nominal diameter gas valve, RZ series of gas with two parallel gate valve for the formation of artificial gas One by one to solve the problem, the maximum diameter of 1600mm. 1, parallel double gate valve in the opening and closing process can scrape the sealing surface of the "gas glue" to solve the gas impurities attached to the sealing surface affect the valve sealing big problem; 2, equipped with stem protection sleeve, so that Valve stem from the "gas glue" erosion; 3, the lower part of the valve with a sewage hole side cover, you can clean the bottom of the valve cavity trash; 4, full-bore design flow resistance, but also through the pig; , The valve body adopts specially designed "squirrel cage frame stiffener" to reduce the overall weight of the valve and enhance the strength and rigidity of the housing; 6, the RZ series gas valve housing is made of gray cast iron with low price; and the seventh Gate valve with a fully enclosed opening and closing indicator, the operator clearly understand the state valve. Three, RQZ series of ductile iron gas valve with parallel double gate valve As China's natural gas into the town, the author with the Shanghai Gas Corporation, Suzhou City Gas Equipment Valve Manufacturing Co., Ltd. according to the characteristics of natural gas has developed a RQZ ductile iron gas with parallel Double gate valve, the gate valve in addition to retaining the characteristics of the RZ series gate valve, the choice of materials to enhance the wear resistance of the valve, while the pressure level raised to high-pressure B-level. Fourth, compared to the butterfly valve butterfly valve above several light, large caliber, the price is low, some of the early eighties gas company - degrees butterfly valve, after about ten years of use, generally considered ineffective. First, the butterfly valve seal to pay isolation width is too narrow, likely to cause valve flap over or not in the process of closure, affecting the seal; Second, the valve in the middle of the valve cavity, flow resistance, can not pass the cleaner; Third, due to Sealing to pay - part of the rubber or PTFE, easy to damage or fall off in the gas flush, the service life is short. Practice has proved that in addition to special locations, the gas pipeline should not be used butterfly valve, some have been using the butterfly valve gas company is (or consider) the replacement of other valves. Five, flat gate valve Flat gate valve is the gas pipeline in recent years began to use the common valve, the whole flow path when the resistance is small, both sides of the seal by the Teflon or rubber O-ring formed on the gate, the valve In full or fully open can not do without gas in the cavity, not easy to repair the user quickly determine whether the valve is closed, to achieve cavitation without gas is the opening and closing torque will increase rapidly; some manufacturers made reduced diameter, column Such as DN200 diameter, diameter of only 150mm, users should pay special attention. Therefore, this type of flat gate valve suitable for lower pressure level, nominal diameter smaller occasions. Sixth, TRZ series of flexible sealing gas gate valve TRZ series of flexible sealing gas gate valve is different from the flat gate valve of a gas valve. The characteristics of the valve and fixed ball valve seat structure similar to the elastic valve, both sides of the ram seal seat with flexible floating structure, the sealing surface in the process of opening and closing and opening and closing always close together, but also to compensate for the wear and tear to pay the seal , Suitable for high pressure level system; the valve in the fully open, fully closed when the valve cavity can be achieved without gas, even after the dispersion of the remaining gas in the valve cavity, the valve cavity is still no pressure. Seven, RQ series ball valve RQ series fixed ball valve is specifically designed and manufactured for the gas industry, the valve combines the characteristics of various types of ball valves at home and abroad, and then developed based on China's national conditions, for gas long-distance trunk line, urban gas facilities shut-off valve . Advantages are as follows: 1, fire resistance, fire After the tempering seal PTFE material on the seat, the metal seal seat and all sealing parts can form a metal to metal seal structure to prevent the diffusion of gas medium to prevent the disaster continues to expand; , Anti-static, ball valve in the process of opening and closing the formation of static electricity easily ignited gas, the ball valve will be static into the ground to ensure the safety of equipment; 3, limit locking, ball valve is the rotating mechanism, easy to cause 360 ​​degree rotation, Outside the organization can then be locked to prevent operator misuse or unauthorized operation of the operator caused the accident; Fourth, ball valve stem seal design with anti-stem impact device, and the use of special O-ring seal, torque than similar ball valve Small, easy to operate, quick opening and closing. Eight, the regulator with the emergency cut-off valve Pressure regulator emergency cut-off valve is an important gas transmission and distribution system security devices. Emergency shut-off valve is in the upper or side of the globe valve to install emergency trip agencies, but also with the regulator body as a whole, but also with the filter into a whole, its role is in the regulator failure, resulting in over-pressure or After the pressure loss, turn off the gas source to ensure safety. The heavy use of natural gas in cities has raised the pressure level of the pipe network. The failure of the pressure regulators will bring disastrous consequences to the cities. The domestic gas industry is paying more and more attention to this. Domestic selection of the product has not yet formed a certain trend, imported, joint venture, domestic, good and bad points, the selection should be cautious. RAQ series of gas emergency shut-off valve is connected with the filter as a whole, the structure of the new compact, high sensitivity, gate valve can set the overpressure (300mm / H2O) and loss of pressure (180mm / H2O) To ensure user safety. Nine, gas emergency shut-off valve Gas boilers, gas air conditioners, gas equipment in the event of gas leaks or other disasters, the emergency shut-off valve quickly cut off the gas source to prevent the disaster from expanding. At present, the gas emergency shut-off valve in the country has not yet popularized, valve companies with the awareness of environmental protection and safety awareness, as well as gas development, gas emergency shut-off valve will certainly get people's attention. Gas emergency shut-off valve is to protect the safety of nature of the valve, and automatic monitoring equipment with the machine, the implementation of the closing valve command, so the gas emergency shut-off valve is electric valve, according to the available information to reflect this type of valve has two types, one is the electromagnetic Valve, one is the electric valve. As the gas emergency shut-off valve demanding, mainly fast, sealed, small flow resistance, size and other safety specifications, the existing solenoid valve, electric valve has some defects, can not meet all its requirements. Ten, gas check valve Gas storage station compressors often need to configure the check valve to prevent gas back into the compressor. The check valve for water has been eliminated in the gas industry. The main disadvantage of the general gas check valve is that the valve plate vibrates with the reciprocating motion of the compressor, causing a great noise when colliding with the valve body and easily damaging the valve plate. The second is sealing Poor sex. R-type gas check valve to better solve these problems. This series of check valve seal pay 90 degrees other check valve to 75 degrees, the valve plate to the valve seat to form a natural pressure, while the valve plate structure plus adjustable balance hammer to solve the sound problem ; Sealing to pay to use PTFE to improve the sealing performance, eliminate the "back to the gas" phenomenon, R-type gas check valve has been available for more than ten years, the ball valve works well.