Pneumatic diaphragm valve structure characteristics and selection principle

pneumatic diaphragm valve is a kind of special form of truncation pneumatic valve, appear Yu Shiji s. Open-close part it is a piece of diaphragm made with soft materials, in the pneumatic valve body cavity with the pneumatic valve cover cavity and drive components separated, therefore calls the pneumatic diaphragm pneumatic valve. Pneumatic diaphragm valve is the most prominent feature is the lower part of the pneumatic diaphragm valve body cavity and upper chamber separated in pneumatic valve cover, make located above the diaphragm of the pneumatic valve stem, pneumatic valve parts from corrosion medium, such as eliminating the packing seal structure, and won't produce leakage of medium.
are usually divided into pneumatic diaphragm valve: often closed type pneumatic diaphragm valve, often open the pneumatic diaphragm pneumatic valve and reciprocating pneumatic diaphragm valve
often closed the details of the pneumatic diaphragm valve:
often closed pneumatic rubber lining pneumatic diaphragm valve product features: GBJ - Type breath often move GBW - 。 GBJ - 。 Type GBFS - 。 Design and manufacture according to: according to GB structure length: according to GB flange size: GB. Test and inspection according to GB/T often closed pneumatic rubber lining pneumatic diaphragm valve
GBJ often closed pneumatic rubber lining pneumatic diaphragm valve purpose and main performance specification:
. GBJ often closed type pneumatic rubber lining pneumatic diaphragm valve series pneumatic diaphragm valve according to different depending on the wrapping material, suitable for different fluid pipeline under different temperature, opening and closing mechanism as control medium flow.
。 GBJ often closed type pneumatic rubber lining pneumatic diaphragm valve recommended range of various kinds of visual wrapping material.
structural characteristics of pneumatic diaphragm valve:
the most prominent feature is the lower part of the pneumatic diaphragm valve body cavity and upper chamber separated in pneumatic valve cover, make located above the diaphragm of the pneumatic valve stem, pneumatic valve parts from corrosion medium, such as eliminating the packing seal structure, and won't produce leakage of medium.
and made of rubber or plastic soft seal diaphragm, sealing is good. Because the diaphragm for wearing parts, should be replaced periodically depending on the dielectric properties.
and restricted by the diaphragm material, pneumatic diaphragm valve is suitable for the occasion of relatively low pressure and temperature is not high.
can be divided into the form of the structure, pneumatic diaphragm valve: house type, once-through, globe type, straight through, ram and right Angle type six kinds; Form is usually connected with flange connection; According to the drive mode can be divided into manual, electric and pneumatic three, including pneumatic drive is divided into often open, often closed and reciprocating three.
and should not be commonly used for temperature higher degrees and organic solvents and strong oxidizing medium pipeline, unfavorable also used in high pressure pipeline.
pneumatic diaphragm valve selection principle:
pneumatic diaphragm valve clamping type pneumatic valve, it mainly in the line for opening and closing.
pneumatic diaphragm valve has two main advantages: one is the pneumatic valve does not need to separate pneumatic valve stem packing seal structure, the diaphragm in the cutting medium at the same time have played an important role of pneumatic valve stem seal, the other is flexibility strong diaphragm close and reliable, even for dispensers can do good to cut off. Therefore, operating mechanism and media channels completely separated, pneumatic diaphragm pneumatic valve can not only apply to the food industry and medical industry, but also applies to some difficult to transport medium and greater danger of medium.
usually, the conditions of use or in sealed performance is strict, mud medium, wear, light structure, low voltage cutoff ( Small pressure difference into the atmosphere when a small amount of leakage, abrasive medium pneumatic diaphragm valve is used in the recommendation. In two position adjustment, throttling, channel shrinkage, low noise, have spirit point and evaporation phenomena and manipulation of the torque of the occasions to use pneumatic diaphragm valve. Medium at high temperature and high pressure medium, high pressure cut-off ( Differential pressure big, quick opening and closing action, structure under the condition of short day length chose not to use the pneumatic diaphragm valve, except the metal diaphragm pneumatic valve.
the structure characteristics of pneumatic diaphragm valve is a set of thin metal film clip of hemispherical solid in pneumatic valve body, as a barrier between the pneumatic valve stem and fluid. Pneumatic valve closing is through the pneumatic valve rod head and metal film the pneumatic valve plate in pressure pneumatic come up to the seat. Pneumatic valve opening is through an internal spring, when the pneumatic valve stem rises and out of contact with the membrane, pneumatic valve tray is rising. The pneumatic valve is equal to the film's trip schedule and thus the characteristics of the pneumatic valve lift is much smaller than general pneumatic valves. In order to overcome the resistance loss caused by low lift, pneumatic seat and circulation area than the average large pneumatic valve, the purpose is to have a larger flow. Owing to the pneumatic valve pneumatic valve seat is larger, the force is much larger than the usual pneumatic valve, in order to get enough on pneumatic valve plate seal force, because pneumatic valve stem and there is no direct contact between pneumatic valve plate. Pneumatic valve plate won't leave by pneumatic valve stem and pneumatic valve seat, thus this pneumatic valve used in differential pressure flow in one direction, and usually medium is from 'pneumatic seat here. But in use should be avoided a lot of reflux, lest affect pneumatic valve closed. In general, choose metal under high temperature and high pressure pneumatic valve diaphragm is economic and effective the pneumatic valve also can choose the don't want to use the synthetic rubber diaphragm pneumatic valve of low temperature and low pressure situations. Pneumatic valve -
pneumatic diaphragm China pump pneumatic valve network quality manufacturers recommend: