Under the maximum pressure of the valve, if the maximum temperature does not exceed the temperature limit of the polymer material+one of the seals can use polymer. It is hoped that the throttling capacity of low leakage can be obtained in the metal metal sealed pneumatic ball valve. The spherical surface of foreign high-temperature pneumatic ball valves is chrome plated. The metal sealing element is 316 stainless steel with Stellite alloy surfacing. The valve diameter is less than l4 inch, and the combined value of temperature and pressure is between ANSI150 and 300 (depending on the valve diameter).

Distinguish the Teflon compensator plane from the non-metallic flexible compensator
The axial outward pressure corrugated compensator is usually used when the gas pipeline passes through the structural expansion joint of the roof (or podium roof). The device position shall generally meet the following conditions:
(1) The compensator plane shall be on the same plane as the straight pipe section.
(2) The center of the compensator shall be on the same vertical line with the center line of the expansion joint.
(3) A fixed support shall be set on both sides of the square compensator. The support position and mode shall be selected by the design.
One end of the compensator should be close to the fixed pipe support. If it is too long, the guide frame should be set according to the setting request of the first guide frame. The maximum spacing of other guide frames can be calculated as follows: LGmax - maximum guide spacing (m); E - Elastic modulus of pipeline data (N/cm2); Inertia moment of i-tp pipe section (cm4); KX compensator axial stiffness (N/mm), X0 compensation amount positioning displacement (mm). When the compensator is compressed and deformed, the symbol "+" corresponds to "-" when it is stretched. When the pipe wall thickness of PTFE compensator is designed according to the standard wall thickness, LGmax can be selected according to the relevant specifications.