Electric butterfly valve, pneumatic valve, flanged butterfly valve, wafer butterfly

About butterfly butterfly (butterfly valve): Also known as flap valve, butterfly valve. Interpretation: opening and closing parts of the disc around the valve disc and to a valve body axis of rotation. Structure: mainly by the body, stem, disc and seal components. Body cylindrical, short axial length, built-in disc. How it works: the disc driven by the stem, if turned 90 °, will be able to complete a hoist. Change disc deflection angle, you can control the flow of media. Butterfly suitable furnace, gas, natural gas, liquefied petroleum gas, city gas, hot and cold air, chemical metallurgy and power generation and environmental protection, water supply and drainage systems and other projects to transport all kinds of corrosive, non-corrosive fluid medium pipe with for regulating and cutting off the flow medium. 2 Functional use butterfly (English: butterfly valve) is closed parts (valve or disc) to the disc around the valve axis to achieve the opening and closing a valve in the main pipeline from the off and throttling. Butterfly is a disc-shaped opening and closing parts of the disc, in the valve body rotating around its own axis, so as to achieve the purpose of opening and closing or adjusting. Valve fully open to fully closed is usually less than 90 °, butterfly and butterfly stroke itself is not self-locking capability, in order to position the disc to install the worm gear on the stem. Using worm reducer, not only can make the disc has a self-locking capability, so that the disc stopped at any position, but also to improve the operating performance of the valve. Industry-specific characteristics of butterfly valves to high temperature, higher pressure range, the valve nominal diameter large, carbon steel valve body, valve plate seal with a metal ring to replace the rubber ring. Large temperature valve welded steel plate manufacturing, mainly for duct smoke and gas pipelines hot medium. 3 electrically adjustable electric adjustable butterfly valves are electric and electric control valve of a species. Connections are: flanged and wafer type. Industrial automation and control is an important execution units. Electric control valve installation points two analyzes: the installation location, altitude, direction and export must meet the design requirements, pay attention to the direction of flow of the medium should be consistent with the direction of the arrow on the valve body, the connection should be firmly tight. Electric control valve must be visually checked before installation, the valve plate should comply with existing national standards, "Universal Valve logo" GB12220's. For working pressure greater than 1.0MPa and the role played off valves on the main pipe before installing the strength and rigorous performance tests should be carried out. Passing behind the prospective use. Strength test, the test pressure is 1.5 times the nominal duration of not less than 5min, the valve housing, packing should be no leakage as qualified. Electric control valve according to the structure can be divided into bias plate, vertical plate, inclined plate and leveraged. Press the seal can be divided into soft and hard seal sealed two. Soft sealing type commonly used rubber ring seal, seal type commonly used hard metal ring seal. 4 selection rules stem diameter: Bright multi-turn on the valve stem. It can not be assembled into electric valve. Therefore, if the electric valve device allows the maximum stem diameter can not be dispensed through the valve stem. The inner diameter of the hollow output shaft of the electric system must be greater than the next shot the valve stem diameter. The local rotary valves and rotary valves in the dark bar valve stem diameter, although not considered by the problem, but should be plenty to consider when matching stem diameter and keyway size, so after assembly to work properly. Operating torque: Operation moment is to select the most important parameters of the valve electric device. Electric butterfly stroke during exercise by size, torque or axial thrust to control. Due to the operating characteristics of valve actuators and utilization depends on the type of the valve, the valve position device specifications and work on the pipeline or equipment, electric butterfly valve device is programmed to achieve the valve, automation and remote control devices indispensable. Therefore, the correct choice of valve electric device, to prevent the emergence of the phenomenon of overload (operating torque is higher than the control torque) is essential. Typically, the correct choice on the basis of electric butterfly valve device. Electric actuator output torque valve operation should be 1.2-1.5 times the maximum torque. Electric butterfly valve operating thrust: the host structure electric valve actuators in two ways: one is not configured thrust plate. Output torque through the thrust plate stem nut is converted to output thrust. Direct output torque; the other is configured thrust plate. Output shaft rotation number: How many electric valve actuators and valve output shaft rotation number of the nominal diameter, stem pitch, thread the first few related. H is the valve opening height, according to M = HZS calculate the total number of turns (M is an electric device should satisfy .S to stem transmission thread pitch, Z for the first few stem threads. 5 pneumatic valve development history of the last century 30 era, the United States invented the butterfly 1950s into Japan, the 1960s was widely used in Japan, but in China it is a matter of promotion of the 1970s after a small operation torque, small installation space and light weight. In an example DN1000 , butterfly about 2T, while the gate of about 3.5T, and the butterfly is easy with a variety of drive combinations, with good durability and reliability. The disadvantage is that the rubber sealing butterfly valve for throttling, due to improper use will produce cavitation, so rubber seat spalling, damage from happening. For this reason metal 80 years -90 years, but will have the choice of how to properly according to the conditions required relationship butterfly valve opening and flow between essentially linearly proportional to the change. If to control the flow, the flow characteristics of the flow resistance is also closely related with the pipe, as the two valve diameter pipe installation, and other forms of the same whole, and the pipe loss coefficient is different, the difference between the flow valve will be great. If the magnitude of the throttle valve larger state, the valve plate on the back prone to cavitation, it is possible to damage the valve, generally used in the 15 ° outside. When the valve is in the opening, the opening shape of the front end of the body and disc formed in the valve shaft as the center, formed on both sides to complete a different state, the front end of the disc along the flow direction of the moving side, the other side of the counter-current of water moving direction, and therefore, one side of the body and the valve plate is formed like a nozzle-shaped opening, similar to the other side of the throttle hole-shaped opening, fast nozzle orifice side than the side of the flow rate, and the throttle valve below will produce negative side, often have rubber seals off. valve operating torque, due to open and close the valve opening direction different from the value of each different horizontal butterfly, especially large-diameter valves, due to water depth, valve shaft, the torque generated by the water head difference can not be ignored. In addition, the valve inlet side of the device bend to form bias, torque will be increased. valve is intermediate opening, due to the flow of water moments work, organizations need to operate self-locking worm gear butterfly valve industry chain of many Chinese, but non-valve power. Overall see that China has entered the ranks of the world's great powers of the valve, but the product quality to Look away from the valve powerhouse China is still a very long gap between the low production of industry concentration, low-end product development capabilities matched valves, valve industry, the low level of manufacturing technology still exists, import and export trade deficit expanded. really survive in the market valve business is definitely not there so much. But this high-speed shock valve industry will bring tremendous opportunities, the results of operation of the market volatility will make more rational. localization of the road end of the valve abnormality "bumpy." China has become a constraint basic parts manufacturing to high-end development of a short board, the government continued to increase during the second five high-end equipment parts localization efforts. here to select a few key development sectors, "plan" mentioned in Feasibility representative valves import substitution analysis can be seen from the analysis of the various sub-sectors of the inlet valve to replace a big difference feasibility, high-end valve needs to more policy guidance and research support. Valve industry in national economic development, as an important part of the equipment manufacturing industry, play a very important role. Because of China's domestic and international advanced level of the valve manufacturing is still a gap compared to the level, a lot of high-parameter, high temperature and pressure, high level of critical valves former pound has been dependent on imports, such as the European OMAL brand has been the main choice of target domestic industry valve applications . To urge the valve made after the State Council issued the "Opinions on Accelerating the development of the equipment manufacturing industry," according to the state departments of major equipment requires the State to make, has made a series of major deployment, led by the National Development and Reform Commission China Machinery Industry Federation and the China General Machinery Industry Association, together with the deployment of developed valve localization of major equipment programs in related fields, and many times in coordination with the relevant departments, and now localization of the valve in the valve industry in China has formed a consensus. Actively adopt international standards for product design; excellent absorption of foreign design structure (including patents); product testing, performance testing carried out in strict accordance with international standards; absorption of foreign advanced production technology and experience of great importance to research and promote the use of new materials; clarify imports high parameters valves technical parameters and operating conditions, such as speeding up the localization process, and promote valve product updates, the full realization of localization only way valve. With the accelerated pace of the valve industry restructuring, the future of the industry is competitive valve product safety and product quality between brands, products to high-tech, high-parameter, strong corrosion resistance, high-life direction, only through constant technological innovation, developing new products, technological innovation, in order to gradually increase the level of technology products to meet domestic devices supporting the full realization of the valve localization. China valve manufacturing industry in the huge demand environment, will exhibit better prospects. 6 major categories by driving points (1) Electric Butterfly (2) pneumatic valve (3) hydraulic valve (4) manual butterfly form of the structure points: (1) central sealing butterfly valve (2) single eccentric sealing butterfly valve (3) Double eccentric sealing butterfly valve (4) three eccentric sealing butterfly valve sealing surface Material: (1) soft sealing butterfly valve. 1) Sealing of soft materials from non-metallic soft nonmetallic materials. 2) Sealing materials from non-metallic rigid metal soft material. (2) metal seal butterfly. Sealing materials from metal to metal hard rigid material. Form by sealing points: (1) mandatory sealing butterfly valve. 1) elastic sealing butterfly valve. Sealing pressure when the valve is closed by the valve plate squeeze resilient seat, seat or valve plate production. 2) applied torque sealing butterfly valve. Sealing pressure generated by the applied torque to the valve shaft. (2) pressurized sealing butterfly valve. Sealing pressure seal or valve seat by playing board member pressurized components produced. (3) self-sealing valve. Sealing pressure is automatically generated by the media pressure. According to the working pressure points: (1) vacuum valve. Working pressure is lower than standard atmospheric heap butterfly calendar. (2) low-pressure valve. Nominal PN100MPa butterfly. Divided by Operating Temperature: (1) high temperature. t> 450 ° C butterfly. (2) Temperature butterfly. 120 C