On the pressure vessel safety what are the requirements for the installation of the pneumatic valve

security pneumatic valve installation shall meet the following requirements:
( ） Pneumatic valve should be installed vertically in the pressure vessel safety level above the gas phase of an empty net, or installed in the connection pipe gas phase pressure vessels tips. Test it
( ） Pressure vessels and safety pneumatic valve hole is the connection between the pipe and pipe fittings, the cross-sectional area shall not be less than safe import area of pneumatic valve.
　　（ ） Pressure vessels and safety between the pneumatic valve should not be installed by the pneumatic valve. For the installation is extremely flammable, toxic, highly, moderate harm or viscous medium pressure vessel, to facilitate safe pneumatic valve replacement, cleaning, can be in pressure vessels and safety between loaded by the pneumatic valve, pneumatic valve by pneumatic valve structure and size of the size should not interfere with the normal discharge of security pneumatic valve. Pressure vessel during normal operation, by the pneumatic valve must be kept fully open, and seal. All use this stop pneumatic valve should be operating records.
　　（ ） Security pneumatic valve installed position, should facilitate the daily inspection, maintenance and repair, and should consider the security can be heard the sound of the pneumatic valve opens. Pneumatic valve installed in the outdoor open-air safety, want to have reliable preventing measures of pneumatic valve water freezing in winter.
　　（ ） Medium to extreme and highly harm or containers of flammable and explosive medium, safety of pneumatic valve outlet shall be led to safety, and properly handle. If two or more security pneumatic valve when sharing a discharge tube, discharge pipe of the cross-sectional area shall not be less than the sum of all security pneumatic valve outlet cross-sectional area, but the oxygen or combustible gases and can react each other of the two gases can't share a discharge tube.