First, why the stainless steel valve two-seater valve small opening task simple oscillation for the single core, when the medium is flow open type, valve stability is good, when the medium is flow closed, valve stability is poor.

The two-seater valve has two spool, the bottom spool is the flow closes, on the valve core lies in the flow opens, like that, is opening the task, the flow closes the valve core to cause the valve the vibration, this is the two-seater valve impermissible uses for the small opening degree task the reason is being. Second, why the double seal valve impermissible as a cut-off valve the advantage of the two-seat valve core is the force misalignment structure, the promise of pressure difference, and its general imperfection is two secret book impermissible simultaneous excellent contact, the formation of leaks big.

If it man-made, forcibly used to cut off the site, obviously ineffective, even for it made a lot of improvements (such as double sealed sleeve valve), is not taken. Third, what direct distance control valve plugging function is poor, angle distance valve to prevent plugging function good straight distance valve spool is a vertical diet, and the medium is the degree of flow into the outflow, the valve cavity flow must be circled round, so that the valve flow path becomes equal simple (shape such as inverted "S" type). In that case, there are many dead zones, for the accumulation of the media takes time, and form a blockage.

Angle distance valve Dieting position is the degree of position, medium level flow into, degree outflow, simple to the dirty media away, the simultaneous flow path is easy, medium accumulation of time is also very few, because the angle distance valve blocking function. Four, why the straight distance conditioning valve stem thinner it touches once easy machine principle: sliding conflict is big, bone conflict is small. Straight distance valve stem high and low activity, the aggregate slightly pressed less than half, it will be the stem pack very tight, a large return to the difference. To this end, the valve stem conceived extremely coarse, aggregate and common conflict coefficient small PTFE aggregate, or reduce back to the difference, but the problem is sent to the stem fine, it is easy to bend, aggregate time is short.

The best way to deal with a problem is to use a trip valve stem, that is, the angle distance type of conditioning valve, it's stem than straight distance stem thick 2~3 times, and the selection of long length of the graphite aggregate, stem just a good, aggregate length of time, the conflict of the opposite angular momentum small, back to small. V. Why is the cut-off pressure difference of the angle distance type valve larger?

Angle distance type valve cutting pressure difference is large, is due to the media is the valve core or valve plate on the unity of the rotation axis occurred in the angular momentum is extremely small, so it can accept a larger pressure difference. Six, why remove the brine medium use the rubber lining butterfly valve, lining fluorine barrier valve use short span? The Demineralized water medium contains low depths of acid or alkali, which are more corrosive to rubber. The erosion of rubber is manifested as contraction, aging, low strength, with the use of rubber lining butterfly valve, barrier valve application results are not the essence of the rubber is not resistant to erosion. After the lining of the rubber barrier valve to improve the corrosion-resistant function of the lining fluorine barrier valve, but the diaphragm of the lining fluorine gap valve is not high and low folding and is broken, the formation of mechanical damage, the valve's span of shorter.

Now the best way is to use water to the public ball valve, it can be applied to 5-8 years. Seven, why the cut-off valve should be too selective hard seal shut-off valve request leaks lower the better, soft seal valve leakage is the lowest, cut off the effect of tens of thousands of good, but not wear-resistant, poor reliability. From the leakage volume is small, sealed and reliable double specification, soft seal cut off the hard seal is not good.

such as the full performance of ultra light conditioning valve, sealed and heap wear-resistant alloy cover, high reliability, leakage rate of up to 10~7, can be satisfied with the request to cut off the valve. Eight, why the sleeve valve replacement single, two-seater valve but did not wish 2000 years 60 times published sleeve valve, 70 times is a small amount of international use, 80 era of the introduction of Sinopec installation of the proportion of the sleeve valve larger, at this time, many people think that the sleeve valve can replace single, two-seater valve, change the second generation of goods. By now, not so, single seat valves, two-seater valves, sleeve valves have lost the equivalent of the use. This is due to the sleeve valve but improved dieting, stability and protection better than a single seat valve, but its weight, block and leak target with single, two-seater valve differences, how can it replace single, two-seater valve?

Because, it can only be used alone. Nine, why say the selection than the intention of the main plan and selection analogy, the selection of the main, much simpler. Because the intended but once easy formula is intended, its own is not the accuracy of the formula, but the given process parameters can be accurate.

Type selection touches to more forms, a little careful, will incur the type of error, not only the formation of artificial, material, financial resources, and the use of the effect is not realistic, bring a lot of application problems, such as reliability, life span, operating quality. Ten, why is the pneumatic valve in execution organization application will be more and more about the pneumatic valve, implementation of the Organization can be adequate application of gas pressure, so that the execution of the Organization's more exquisite than the film-type, thrust greater, in the O-ring than the plastic film, so its use will be more and more.