Просмотр исходного текста страницы Участник:Cramagtuter

== KSB Valves Dealers ==

1. Why's the two-seat valve vulnerable to oscillation when working under small opening conditions?

For single-core valves, in the event the medium is flow-open type, they're stable. In the event the medium is flow-closed type, they're unstable. There're two valve cores from the two-seat valve. The bottom core is flow-closed condition while the upper core is flow-open condition. In this case, under small opening conditions, the flow-closed sort of valve core will easily cause oscillation from the valve. This is why two-seat valves can be used as small opening conditions.

2. Why can't double-sealing valves be utilized for sanitary shut-off valves?

Two-seat valve core has the benefit from balanced force double-sealing valve structure, allowing a big pressure difference. And its particular shortcoming is the two sealing surfaces cannot be in good contact as well, creating a large leakage. If it is purposefully and mandatorily utilized in shut-off occasions, the consequence will not good, even if lots of improvements are already made into it. (including double-sealing sleeve valve)

3. Each and every the straight stroke sanitary regulating valve possess a poor anti-blocking performance and rotary stroke regulating valve have a good anti-blocking performance?

The main of straight stroke valve is vertical throttle, though the flow direction from the medium is horizontal. So there has to be a great deal of twists and turns in valve cavity flow channel, making the flow paths from the valve very complex. Therefore, there're plenty of blind zones that offer space for deposition with the medium, which in the long run causes clogging. The throttle direction of rotary stroke valve is horizontal, the medium horizontally flows inside and out, which can easily remove unclean medium. Meanwhile, the flow path is easy, as there are little room for medium deposition, so rotary stroke valve includes a good anti-blocking performance.

4. How come the stem of straight stroke regulating valve thin?

It involves an easy mechanical principle: the greater the sliding friction, the smaller the rolling friction. The stem of straight stroke valve moves up and down. When the stuffing slightly pressed just a little tighter, it will wrap the stem tightly, providing a large hysteresis. As a consequence, the valve stem is designed to be thin and small and the stuffing use PTFE that features a small friction coefficient so that you can lessen the hysteresis. Perhaps the biggest issue that derives from this really is that a thin valve stem is easy to bend along with the stuffing features a short service life. To solve the problem, the simplest way is to use rotary valve stem, a regulating valve exactly like the rotary stroke ones. Its valve stem is 2-3 times thicker compared to the straight stroke valve. And yes it uses graphite stuffing with a long service life. The valve stem stiffness is great, the service life of stuffing is long, the friction torque and hysteresis are instead small.

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

It's because the torque about the rotating shaft manufactured by the force of medium on valve core or valve plate is very small.

6. Why is the service duration of desalination water medium short when using rubber lined butterfly valve and fluorine lined diaphragm valve?

The medium of desalination water contains low concentrations of acid or alkali, which can be pretty corrosive to rubber. The corrosion of rubber is exemplified by expansion, aging and occasional strength. The poor aftereffect of using rubber lined butterfly valve and diaphragm valve is in fact a result of the intolerance of corrosion of rubber. Rear rubber-lined diaphragm valve has enhanced is the fluorine lined diaphragm valve which has a good tolerance of corrosion. However the lining of diaphragm of fluorine lined diaphragm valve can't withstand the up-and-down folding and it is broken, leading to mechanical damage and shorter service lifetime of the valve. The actual best method is with water treatment special ball valves, which can be used for 5 to 8 years.

7. Why must shut-off valves try to use hard sealing?

Sanitary shut-off valves have to have the leakage to be as small as possible. The leakage of soft sealing valve is the lowest, and so the shut-off effect is certainly good. But it's not wear-resistant, not reliable. Judging in the double standard of small leakage and reliable sealing, soft sealing shut-off isn't as good as hard sealing shut-off. Take full-featured ultra-light regulating valve for example, it's sealed and piled with wear-resistant alloy for defense, highly reliable, carries a leakage rate of 10 to 7, that curently have met the demands of shut-off valves.

8. Why can't sleeve valves replace single-seat and double-seat valves?

Sleeve valves, which first appeared within the '60s, were traditionally used in the '70s worldwide. Sleeve valves be the cause of a substantial percentage in petrochemical equipment imported throughout the '80s. During those times, many people thought sleeve valves could replace single-seat and double-seat valves being the second-generation products. Until now, that isn't the situation. Single-seat valves, double-seat valves and sleeve valves are equally used. Like sleeve valves only increase the strategy for throttle, have better stability and maintenance than single-seat valves. However its weight, anti-blocking and leakage indicator are the same as that regarding single-seat and double-seat valves.

9. Why's selection more valuable than computation?

Compare computation with selection, selection is a lot more important and much more complicated. Computation is simply a simple formula. It isn't the formula itself, but alternatively the truth of given parameters that matters. Selection involves a lot of things, being a bit careless can result in improper selection, which not merely ends in the waste of manpower, material, and cash, but the connection between use usually are not good, creating a quantity of problems being used, for example reliability, service life and quality, etc.

10. How come piston actuator increasingly utilized in pneumatic valves?

For pneumatic valves, the piston actuator will make better use of air pressure to make the height and width of the actuator small compared to that relating to the show type. The thrust is larger. The O-ring within the piston is additionally more reliable than that of the video. Overall, it's increasingly used.

Each year KSB manufactures almost a thousand valves. All the various valves on offer catches the interest of numerous applications.
We're Dealer & Exporter of all types of business Valves in India, In Mumbai, Established in 2005.


For details about KSB Valves Suppliers in India net page: [https://www.unitedvalves.in/valves/ksb-valve read here].