Pilot operated safety structure characteristics and working principle of the pneumatic valve

the guide type safety pneumatic valve is a safety protection with pneumatic valve, under the action of the open-close part affected by external forces in a normally closed state, when the equipment or piping within the medium pressure increases, more than a specified value automatically when open, through a discharge medium system to prevent the pipeline or equipment within the medium pressure in excess of the prescribed value. Pilot operated safety pneumatic valve is widely used in natural gas, liquefied petroleum gas (LPG) pressure vessels and chemical equipment and industrial pipes, fire explosion proof, antistatic, reliable sealing, opening and closing fast and large displacement of outstanding advantages.
the guide type safety pneumatic valve working principle and structural characteristics of parsing
the guide type safety pneumatic valve structure
the guide type safety pneumatic valve by the main pneumatic valve, pneumatic valve, discharge valve, connector and ducts, etc. Under normal conditions, the system of the medium pressure role both in the bottom of main pneumatic disc, and ACTS on the top of the main pneumatic disc.
because of the air chamber above the main pneumatic disc area below the area in the medium, medium under the action of pressure difference, the main pneumatic valve in the closed state. As the pipeline medium pressure rising, the sealing of seal pressure with will also rise, this type safety pneumatic valve and spring load directly opposite, namely the medium pressure, the higher the more reliable. When the pipeline medium pressure abnormalities, meet or exceed the setting pressure, pneumatic valve guide ( Figure on the pneumatic disc quickly open, above the main pneumatic disc through the guide of the pneumatic valve exhaust gas indoor medium joint discharge rapidly, in the main pneumatic disc under medium pressure under the action of strong, instantaneous open, the medium from the main exports of pneumatic valve quickly a large number of discharge, medium in the pipeline pressure returned to normal work, ensure the security of the system.
when the pipeline medium pressure to the system set the safety of the pneumatic valve setting pressure about %, guide on the pneumatic valve pneumatic valve closed, pipeline interface and through pneumatic valve guide into the main pneumatic valve at the top of the chamber. Under the action of pressure difference, the main pneumatic valve closed, guarantee the normal work of the system.
the guide type safety working principle of the pneumatic valve
guided under pneumatic valve by pneumatic valve, pneumatic valve, plunger, deflated joints, pneumatic valve, pneumatic valve spring and discharge, etc.
under normal conditions, guide on the pneumatic valve pneumatic valve closed, guide under the pneumatic valve pneumatic valve is fully open. Through the pipeline medium pneumatic disc into the main pneumatic disc at the top of the indoor gas, to close the valve flap of the pneumatic. When the pipeline medium pressure is unusual, meet or exceed the whole concentration set, guide under the pneumatic valve pneumatic valve in the closed, under the action of medium pressure to cut off the pipeline medium into the pneumatic valve at the top of the main channel, at the same time guide on the pneumatic valve pneumatic valve plunger, jacking, namely guide pneumatic valve open, above the main pneumatic disc through the vent gas of indoor medium joint discharge quickly. Below main pneumatic disc medium pressure under the action of strong, instantaneous open, the pipeline medium from the main exports of pneumatic valve quickly a large number of discharge, the pipeline medium pressure returned to normal work, ensure the safety of the system. When the pipeline pressure drop to system set by the setting pressure about %, guide on the pneumatic valve pneumatic disc in the spring under the action of closing, at the same time guide pneumatic valve pneumatic disc are open plunger, pipeline medium through the pneumatic disc into the pneumatic valve at the top of the chamber, in main pneumatic disc close under the action of pressure difference, ensure the normal operation of the system.
when detect pipeline medium pressure, pneumatic valve failure guide failed to open, can be manually make the discharge of the channel on the pneumatic valve pneumatic valve, release of indoor gas above the main pneumatic disc medium, make the main pneumatic disc opens, abnormal pressure release of the pipeline medium, ensure the safety of the system.
the guide type safety pneumatic valve installation requirements
( l） Evaporation is greater than the rating. T/h boiler, installed at least two pilot operated safety pneumatic valve: less than or equal to the rated evaporation. T/h boiler, at least with a pneumatic valve safety. Split the economizer exit, steam superheater outlet must be installed pilot operated safety pneumatic valve.
( ） Pilot operated safety pneumatic valve should be installed vertically in the pot, the top of the header. In the security between pneumatic valve and the drum or header, shall not be equipped with access steam outlet pipe and the pneumatic valve.
( ） Pilot operated safety pneumatic valve to prevent heavy hammer to mobile devices and on its own limitation lever deviant guide frame, spring loaded safety pneumatic valve to have raise a hand and prevent twisted casually adjusting screw of the device.
( ） For the steam pressure is less than or equal to the rated. MPa boiler, pilot operated safety pneumatic valve throat diameter should not less than the mm: for steam pressure is greater than the rating. MPa boiler, safety pneumatic valve throat diameter should not less than the mm.
( ） Pilot operated safety pneumatic valve and connecting pipe of boiler, its cross-sectional area should not be less than the safety of pneumatic valve import cross-sectional area. If several security pneumatic valve installed on a common attached directly to the drum on the spool, spool access cross-sectional area should not step in pneumatic valve exhaust all security area. Times.
( ） Pilot operated safety exhaust pipe of pneumatic valve should be installed commonly exhaust steam pipe should be road safety, and have enough area, ensure the exhaust steam flow. Security pneumatic valve at the bottom of the exhaust pipe should be put on AIRS have received safety drain pipe, on the exhaust pipe and drain pipe, are not allowed to furnish the pneumatic valve.