The ten common problems occurring in the use of pneumatic valve

one, why two-seater small open of the pneumatic valve is working easy oscillation
for single core, when the medium is away, pneumatic valve stability is good; When the medium is flow closed type, poor stability of pneumatic valve. Two-seater pneumatic valve has two pneumatic valve core, the pneumatic valve core in the flow close, pneumatic valve core in the flow, in this way, when you are working in a small open degree, the flow of the closed type pneumatic valve core is easy to cause the vibration of the pneumatic valve, which is two-seater pneumatic valve can not be used in small open degree of work.
2, why can't a double seal pneumatic valve used as cut off the pneumatic valve
two-seater pneumatic valve pneumatic valve core has the advantage of force balance structure, allow the pressure difference is big, but its disadvantage is that the two seal face not good contact at the same time, cause leakage. If it is used to cut off at artificially, mandatory, obviously the result is bad, even as it made many improvements ( Such as double seal sleeve pneumatic valve) It is not desirable.
3, pneumatic valve stem what straight stroke control performance is poor, held in quarter-turn pneumatic valve performance is good
straight travel pneumatic valve pneumatic throttle valve core is vertical, and medium level, pneumatic valve cavity flow is bound to turn down turn, make pneumatic valve flow becomes quite complex ( Shapes such as 'S' type) 。 In this way, there is a lot of dead zone, provide the space for medium of precipitation, in the long term, causing congestion. Quarter-turn pneumatic valve throttle direction is horizontal, flow into the medium level, level, easy to take unclean medium, flow simple at the same time, the precipitation of medium space is very few, so held in quarter-turn pneumatic valve performance is good.
4, why the straight stroke regulating pneumatic valve pneumatic valve stem is fine
it involves a simple mechanical principle: large sliding friction and rolling friction is small. Straight travel pneumatic valve pneumatic valve rod moves up and down, packing a little pressure, it will be tightly wrapped pneumatic valve stem, produce bigger return difference. Therefore, pneumatic valve stem design very tiny, packing and commonly used small friction coefficient of ptfe packing, in order to reduce the return difference, but the problem is sent pneumatic valve stem thin, easy to bend, packing and short service life. Travel the best way to solve this problem, is to use pneumatic valve pneumatic valve stem, namely quarter-turn class regulating pneumatic valve, its pneumatic valve stem ~ times thicker than straight travel pneumatic valve stem, and select long-life graphite packing, pneumatic valve stem good stiffness, packing long life, instead of the friction torque is small, poor little back.
5, why quarter-turn pneumatic valve to cut off the pressure difference is bigger?
quarter-turn kind of pneumatic valve to cut off the pressure difference is bigger, because the medium on the pneumatic valve core or pneumatic valve plate of resultant force on the rotating shaft torque is very small, so it can bear large pressure difference.
6, why desalting water use line with rubber butterfly pneumatic valve, short service life of lining fluorine pneumatic diaphragm valve?
desalted water medium containing low concentration of acid or alkali, they have larger corrosion in rubber. Rubber corrosion performance for expansion, aging, low intensity, with rubber lining the pneumatic butterfly valve, pneumatic diaphragm valve use effect is the essence of which is the rubber is not caused by corrosion. After the rubber lining pneumatic diaphragm valve to improve the corrosion resistance of good lining fluorine pneumatic diaphragm valve, but lining fluorine pneumatic valve diaphragm and diaphragm are folded up and down and were broken broken, mechanical damage, the service life of pneumatic valve. Now is the best way to deal with water special pneumatic ball valve, it can be used to ~ years.
7, why to cut off the pneumatic valve should choose hard seal
as far as possible to cut off the pneumatic valve for leakage is lower, the better, soft seal leakage of pneumatic valve is the lowest, to cut off the effect of course good, but not wear-resisting, poor reliability. From small leakage and sealing and reliable double standards, soft seal cutting is not as good as hard seal cut off. As a fully functional ultra light regulating pneumatic valve, sealing and pile has wear-resisting alloy protection, high reliability, the leakage rate of ~ and have been able to meet the requirements of cut off the pneumatic valve.
eight, why pneumatic valve instead of a single, two-seat pneumatic valve sleeve but I did not get it
century s of pneumatic valve sleeve, s at home and abroad, a large number of use, s introduced in petrochemical plant of pneumatic valve sleeve ratio is larger, at that time, many people think, sleeve pneumatic valve, pneumatic valve can replace single, two-seat became the second generation product. By now, is not the case, single-seat pneumatic valve, two-seater pneumatic valve, pneumatic valve sleeve are equal. This is because the sleeve pneumatic valve is improved form of throttle, stability, and safeguard in single-seat pneumatic valve, but it weight, prevent leakage and indicators are consistent with single, two-seat pneumatic valve, it can replace single, two-seat pneumatic valve? So, can only be used together.
9, why do you say selection is more important than computing
calculation and selection of comparison, selection is much more important and more complex. Because computing is just a simple formula, its itself is not the accuracy of the formula, but in a given by process parameters are accurate. Selection involves the content is more, a little careless, will lead to improper selection, not only a waste of manpower, material resources, financial resources, and use effect is not ideal, bring some use problems, such as reliability, quality of life, running, etc.
ten, why piston actuator used in pneumatic pneumatic valve will be more and more
for pneumatic valves, pneumatic piston actuator can make full use of air pressure, make the size of the actuator is smaller than the film type, thrust is bigger, the piston o-rings, than film is reliable, so it will be more and more.