Pneumatic valve and pneumatic valve advantages and disadvantages compared

Pneumatic valve and pneumatic valve pneumatic valve is an individual, using the body to rotate around the axis of the stem ° to realize the purpose of opening and closing. Pneumatic valve in the line is mainly used for cutting, distribution, and change the flow direction of medium, designed to open V of the pneumatic valve also has a good flow regulating function. Pneumatic valve and pneumatic valve is different, it is the disc type opening and closing a reciprocating swing around ° to open and close and regulating fluid channel of a valve. The characteristics of the pneumatic valve: blocking and secretion: when the valve is in closed condition, upstream and downstream side of the seat to make liquid blocking, body lumen of stagnant objects can be secreted by production equipment. Automatic pressure relief structure: a temporary cavity pressure when adding phenomenon appears disorder, lumen medium can rely on itself thrust to push the seat and automatic pressure release, and ensure the safety of the valve lift. Stem reliable seal: stem selection has poured sealing bottoms type structure, pour sealing force with medium pressure increases with increasing of the seal, so it can ensure the reliable sealing of the valve stem, and when the stem disorder booster, the valve stem will not spit out. Fire prevention structure: according to the working condition and the needs of users, valve can plan for fire protection structure. Anti-static structure: when operating valves, due to the friction between body and seat, to attack the cow and electrostatic charge accumulation in the body, to prevent attacks spark, in the valve set on static equipment, export charge will accumulate in the body. Pneumatic valve in the pipeline is mainly used for cutting speed is quick, distribution, and change the flow direction of medium. Pneumatic valve is a new type of valve, it has the following advantages:, small fluid resistance, the resistance coefficient with section of equal length. , simple structure, small volume, light weight. And reliable closely, valve sealing surface of materials widely used plastic, sealing good, also has been widely used in the vacuum system. , easy to operate, open and close quickly, from open to close as long as the rotating °, is advantageous for the remote control. Pneumatic valve has simple structure, convenient maintenance, and seals are generally activities, remove the replacement is more convenient. , in full open or full close, body and seat sealing surface and the dielectric isolation, medium through, does not cause the valve sealing surface erosion. , wide applicable scope, size from small to several millimeters, big to a few meters, from high vacuum to high pressure can be applied. , because of the pneumatic valve is gas that is used by the power supply is commonly, - , MPa pressure, is relatively safe. Pneumatic valve if air leakage, the relative hydraulic, electric, gas can directly discharge, no pollution to the environment, and has higher security. , relative to manual and turbine rotating valve, pneumatic valve can be large caliber configuration, ( Manual and turbine rotational valve is generally below DN caliber, pneumatic valve can achieve DN caliber. ） Disadvantages are as follows: and its regulation performance relative to the globe valve is less, especially the pneumatic valve; , as major part of the pneumatic valve seat sealing material is teflon, it for almost all of the chemicals are inert. But the physical properties of ptfe, including high expansion coefficient, sensitivity of cold flow and poor heat conductivity, seating requirements of the design must revolve around these features. When sealing material hardening, the reliability of the seal is damaged. And, of ptfe heat resistance level is low, can only be used under the condition of less than ℃. More than this temperature, sealing materials will be aging. If want to long-term use of general advice in ℃; , as major part of the pneumatic valve seat sealing material is teflon, it for almost all of the chemicals are inert. But the physical properties of ptfe, including high expansion coefficient, sensitivity of cold flow and poor heat conductivity, seating requirements of the design must revolve around these features. When sealing material hardening, the reliability of the seal is damaged. And, of ptfe heat resistance level is low, can only be used under the condition of less than ℃. More than this temperature, sealing materials will be aging. If want to long-term use of general advice in ℃; Pneumatic valve: the advantages of convenient, opening and closing rapidly, energy saving, fluid resistance small, can often operate. , brief structure, small volume, light weight. And can transport the mud, and the apertures least accumulated liquid. , low pressure, can complete the outstanding seal. , recuperate good performance. Faults:, pneumatic valve sealing performance relative to the pneumatic valve, pneumatic valve is bad, so used for sealing requirement is not high; And as a result of the limitation of the structure of the pneumatic valve and seal materials, should not be used in high temperature and high pressure in the pipeline system. General working temperature under ℃, PN below; , pneumatic valve, flow regulating range is not big, when open up to % to nearly % above the traffic; Pneumatic valve and pneumatic valve under the condition of certain work, do not allow the use of the contraction of valve. This is in order to reduce pipeline resistance loss on the one hand, on the other hand is to avoid size shrinkage after create obstacles to mechanical cleaning the pipeline.