By the pneumatic valve and pneumatic diaphragm valve structure

the pneumatic valve is closed ( Pneumatic disc) Move along the center line of the pneumatic valve seat of pneumatic valve. According to the mobile form of pneumatic valve, pneumatic valve seat with pneumatic disc change in his itinerary directly proportional relationship. Due to stop pneumatic valve pneumatic open or close the valve stem travel relatively short, and very reliable cutting function, and due to the change of pneumatic seat his trip proportional relationship with the pneumatic valve, is very suitable for the traffic regulation. Therefore, this type of pneumatic valve is very suitable for as a cut or adjust and throttling. Advantages:

(1) in the process of opening and closing, the pneumatic valve with pneumatic valve sealing surface friction than the brake in the pneumatic valve is small, and wear resistance.
(2) the opening are generally only for pneumatic seat/channel, so the pneumatic valve is much smaller than the gate;
3. Usually on the pneumatic valve body and disc only a sealing surface, thus making craft is good, easy to maintenance.
4. Because of its general for asbestos packing with a mixture of graphite and consequently higher heat resistance level. Steam pneumatic valves are commonly used by the pneumatic valve.
drawbacks: (1) due to the flow direction of medium by a pneumatic valve has changed, so the minimum flow resistance by the pneumatic valve is higher than most other types of pneumatic valves; (2) because of a long journey, open the pneumatic ball valve slowly.

pneumatic valve refers to the pneumatic diaphragm valve and pneumatic valve cover is equipped with a flexible membrane or diaphragm, the closing member is connected to the diaphragm of a compression device. Pneumatic valve can Cuo weir shape, also can be straight flow tube wall. Advantages:

(1) operation pathway is separated with the media, not only to ensure the working medium of pure, but also to prevent the pipeline medium impact operating mechanism in the possibility of working parts, pneumatic valve stem place does not need to use any form of single seal, unless in controlling harmful medium for the use of the safety facilities;
(2) because the job is only in contact with the medium and pneumatic diaphragm valve body, both can be used in a variety of different materials, so the pneumatic valve to ideal to control a broad range of working medium, especially suitable for medium with chemical corrosion or suspended particles.
3. Simple structure, only by pneumatic valve, diaphragm and pneumatic valve cover assembly of three parts. The pneumatic valve is easy to be fast disassembly and maintenance, replacement of the diaphragm can be done in the field and in a short period of time. Shortcoming is:

(1) due to the aerodynamic body lining process and manufacturing technics of diaphragm and restrictions, large aerodynamic body lining and larger diaphragm manufacturing process is very difficult, so the diaphragm should not be used for large diameter, commonly used in the pipeline under the DN mm or less.
2. Due to limited by diaphragm material, pneumatic diaphragm valve is suitable for the occasion of low pressure and temperature is not high. Is generally not exceed ℃;
(3) regulating performance is relatively poor, only on a small scale adjustment, In commonly close to/when opening, can be used for flow control) 。
security pneumatic valve refers to the pressure containers, equipment or piping, as the overpressure protection device. When the pressure inside the equipment, containers, or line exceeds allowable values, pneumatic valve automatically opens, then the amount of emissions, in order to prevent the equipment, containers, or line and the pressure continues to rise; When pressure is reduced to the specified value, pneumatic valve should be automatically closed in time, in order to ensure the safety of the equipment, containers, or line running. Pneumatic valve, steam trap in the transmission media such as steam, compressed air, there will be some condensate formation, in order to guarantee the efficiency and safety operation of the unit to should be timely to discharge these useless and harmful medium, to ensure the consumption and use of equipment.
it has the following functions:
(1) can rapidly remove the condensate;
(2) to prevent steam leak;
(3) to exclude air and other no non-condensable gas.