Stainless steel valve ten common problems

1. why stainless steel valve double seat valve small opening task simple oscillation for single core, when the medium is open flow type, the valve stability is good; When the medium is closed flow type, the stability of the valve is poor. The double-seat valve has two valve cores, the lower valve core is closed for flow and the upper valve core is open for flow. In that way, when the valve is in a small opening task, the closed valve core simply causes the valve to vibrate. This is why the double-seat valve cannot be used for small opening tasks.

2. why the double-sealed valve should not be used as a shut-off valve. The advantage of using the valve core of the double-seat valve is that the force is out of balance structure and the pressure difference is large, while its general deficiency is that the two secret book skins make excellent contact with each other, resulting in large leakage. If it is used artificially and compulsively to cut off the place, the obvious effect is not good, even if it has made many improvements (such as double-sealed sleeve valve), it is not acceptable.

3. what kind of straight distance conditioning valve has poor anti-blocking function, and the angle distance valve has good anti-blocking function. The valve core of the straight distance valve is on a vertical diet, while the medium flows in and out to a certain extent. The flow channel in the valve cavity must turn upside down in circles, making the flow path of the valve equal and simple (the shape is like an inverted "S" shape). In that way, there are many dead zones, which take time for the accumulation of the medium, and over time, blocking is formed. The dieting position of the angular distance valve is the degree position. The medium degree flows in and the degree flows out. The non-pickled medium is simply taken away. The simultaneous flow path is easy and the medium accumulation time is very small, because the angular distance valve has good anti-blocking function.

4. why the straight path conditioning valve stem is thinner it touches the once easy machine principle: sliding conflict is big, bone conflict is small. Straight distance valve stem high and low activities, the aggregate slightly compact half, it will be the stem wrapped very tight, a larger return difference. For this reason, the valve stem is assumed to be extremely coarse, and the aggregate is also common with tetrafluoro aggregate with small conflict coefficient, which does not reduce the return difference. However, the problem caused by this is that the valve stem is fine, which is easy to bend and the aggregate life is short. To deal with a certain problem, a better way is to use the valve stem of the traveling valve, that is, the regulating valve of the angular distance type. Its valve stem is 2-3 times thicker than the valve stem of the straight distance, and graphite aggregate with long service life is selected. The valve stem is just good, the aggregate has a long service life, and its conflict momentum moment is opposite and the return difference is small.

Stainless steel valve ten common problems

5. why is the angle of the type of valve cut off pressure difference is larger? Angle of the type of valve cut off pressure difference is larger, is due to the medium is occurring on the spool or valve plate for the rotating shaft of the unity of the moment of momentum is extremely small, therefore, it can accept a larger pressure difference.

6. why the use of desalted water medium rubber lined butterfly valve, fluorine barrier valve service life is short? The desalted water medium contains low depth of acid or alkali, they are more aggressive to rubber. The erosion of rubber is reflected in shrinkage, aging and low strength. The use of rubber-lined butterfly valves and barrier valves is ineffective. Its essence is that rubber is not resistant to erosion. The rear rubber-lined barrier valve is improved to a fluorine-lined barrier valve with good erosion resistance, but the diaphragm of the fluorine-lined barrier valve cannot withstand high and low folding and is broken, resulting in mechanical destruction and shortening the life of the valve. Is now a better way is to use water from the public ball valve, it can be used to 5 to 8 years.

7. why the cut-off valve should be excessive selection of hard seal cut-off valve request leakage as low as possible, soft seal valve leakage is low, cut off the effect of tens of millions of good, but not wear-resistant, reliable poor. Judging from the double norms with small leakage and strong sealing, soft seal cutting is not as good as hard seal cutting. Such as full performance ultra-light conditioning valve, sealed and stacked with wear-resistant alloy cover, high reliability, leakage rate of 10~7, once can be satisfied with the request of the shut-off valve.

8. why the sleeve valve took over the single and double seat valves but did not get what he wanted. The sleeve valve published in the 20th century and the 60th century was being used in a small amount at home and abroad. The sleeve valve introduced in the 80th century accounted for a large proportion in Sinopec's installation. At this time, many people thought that the sleeve valve could replace the single and double seat valves and change the second generation of goods. Up to now, this is not the case, single seat valve, double seat valve, sleeve valve have lost the same use. This is due to the sleeve valve but improved diet, stability and protection is better than the single seat valve, but its component, anti-blocking and leakage target and single, double seat valve differences, how can it replace the single, double seat valve? Because, it can only be used alone.

Why do 9. say that the selection is more important than the intention

Compared with the selection, the selection is much more important and simpler. Because of the intended but once easy formula, it does not lie in the accuracy of the formula itself, but in the accuracy of the given process parameters. There are many forms involved in selection. A little care will lead to selection errors, which will not only lead to the waste of labor, material resources and resources, but also bring about many application problems, such as reliability, life span, operation quality, etc.

10. why more and more executive organizations are being used in pneumatic valves. As far as pneumatic valves are concerned, the executive organizations can fully apply the air source pressure to make the executive organizations more exquisite and thrust than the plastic film type. The O-ring in the pneumatic valves is also stronger than the plastic film, so its use will be more and more.