Top 10 Problems When Using Regulating Valves


1. What’s the two-seat valve likely to oscillation when functioning under small opening conditions?

For single-core valves, when the medium is flow-open kind, they are stable. After the medium is flow-closed kind, they are unstable. You will find two valve cores from the two-seat valve. The lower core is in flow-closed state while the upper heart is at flow-open condition. In cases like this, under small opening conditions, the flow-closed type of valve core will readily induce oscillation of the valve. This is why two-seat valves may be used for small opening conditions.

2. Why can not double-sealing valves be utilized as sanitary shut-off valves?

Two-seat valve core has the benefit of balanced force double-sealing valve arrangement, allowing a huge pressure difference. When it’s intentionally and mandatorily used in shut-off events, the result won’t be great, even if a lot of improvements have been created on it.

3. Why does the straight stroke sanitary regulating valve possess a poor anti-blocking functionality and rotary stroke regulating valve possess a fantastic anti-blocking performance?

The core of straight stroke valve is perpendicular throttle, but the flow direction of this medium is horizontal. Therefore there must be plenty of twists and turns in valve cavity flow channel, which makes the flow paths of the valve quite intricate. Thus, there’re a whole lot of blind zones which provide space for deposition of this mild, which in the long term causes clogging. The throttle management of inkjet stroke valve is horizontal, the medium flows in and out, which may easily remove unclean medium. The flow path is straightforward, and there is little room for moderate deposition, therefore rotary stroke valve includes a fantastic anti-blocking performance.

4. Why is the stem of straight stroke regulating valve thin?

It involves a simple mechanical principle: the bigger the sliding friction, the smaller the rolling friction. The stem of stroke valve moves up and down. If the stuffing slightly pressed a little tighter, it would wrap up the stem closely, resulting in a large hysteresis. To this end, the valve stem was made to be lean and small and the stuffing use PTFE which has a little friction coefficient to be able to reduce the hysteresis. But the problem that derives from this is a thin valve stem is easy to bend along with the stuffing has a short service life. To solve the issue, the best way is to use rotary valve stem, a controlling valve like the rotary stroke types. Its valve stem is 2 to 3 times thicker than that of the right stroke valve. And it uses graphite stuffing that has a long service life. The valve stem stiffness is good, the service life of stuffing is lengthy, the friction torque and hysteresis are instead small.

5. Why does the rotary stroke valve have a relatively large shut-off pressure gap?

It’s because the torque on the rotating shaft produced by the power of medium on valve core or valve plate is quite small.


The medium of desalination water includes low concentrations of acid or alkali, which can be pretty corrosive to rubber. The corrosion of rubberized is exemplified by expansion, aging and reduced strength. The inadequate effect of using rubber lined butterfly valve and diaphragm valve is actually caused by the intolerance of corrosion of rubber. Back rubber-lined diaphragm valve is enhanced to be the fluorine lined diaphragm valve which has a fantastic tolerance of corrosion. However, the lining of diaphragm of fluorine lined diaphragm valve can not defy the up-and-down folding and can be broken, resulting in mechanical damage and shorter service life of this valve. Now the very best method is to utilize water therapy special ball valves, which may be utilized for 5 to 8 years.

7. Why should shut-off valves try to use hard cleaning?

Sanitary closed valves require the leakage to be as low as you can. The leakage of soft sealing valve would be the cheapest, therefore the shut-off effect is certainly good. But it’s not wear-resistant, not dependable. Judging from the double standard of small leakage and reliable sealing, soft sealing shut-off is not as good as hard sealing shut-off.


Sleeve valves, that first emerged in the ’60s, were widely used in the ’70s worldwide. Sleeve valves account for a large percentage in petrochemical gear stolen during the ’80s. At that moment, many people believed wing valves could substitute single-seat and double-seat valves to become the second-generation products. Until today, that is not the situation. Single-seat valves, double-seat discs and sleeve valves are equally employed. That’s because sleeve valves only improve the way of throttle, have better stability and upkeep than single-seat valves.

9. Why is choice more important than computation?

Compare computation with choice, selection is much more important and more complex. Computation is only a very simple formula. Selection Industrial Diaphragm Valve involves a lot of things, being a bit careless will lead to improper selection, which not just results from the waste of labour, material, and cash, but the effects of use are not great, causing a number of problems in usage, such as reliability, service life and quality, etc..

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