Pneumatic valves often meet ten big problem

, why to cut off the pneumatic valve should try to choose hard seal?
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, leakage rate da , have been able to meet the requirements of cut off the pneumatic valve.
, why double seal pneumatic valve cannot be used as a cut-off 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 pneumatic valve, double sealing sleeve is not desirable.
why two-seater pneumatic valve, small open degree of easy oscillation when work?
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.
what straight travel, held in regulating pneumatic valve performance is poor, held in quarter-turn pneumatic valve performance is good?
straight travel pneumatic valve pneumatic throttle valve core is vertical, while the medium is horizontal, pneumatic valve cavity flow is bound to turn down turn, make pneumatic valve flow becomes quite complex ( Appearance is like '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.
why straight travel, regulating pneumatic valve pneumatic valve stem is fine?
straight stroke regulating pneumatic valve 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.
and 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 produced by the resultant force on the rotating shaft torque is very small, so it can bear large pressure difference.
why pneumatic valve sleeve, instead of a single, two-seat pneumatic valve but I did not get it?
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.
why, desalted water medium using 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 poor, its essence 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.
why, in the pneumatic piston actuator used in 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.
, why do you say type selection is more important than the calculation?
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.