Air insulation valve spool to the use of oriented structure, the valve structure is compact, S was streamlined, the channel, so that the pressure drop loss, flow, and wide tuning range, high accuracy flow characteristics, in line with the IEC534 standard. Jacket insulation pneumatic control valves are suitable for the occasion in need of insulation. When the crystallization temperature of the process medium below the ambient temperature or fluid temperature decreases, causing the viscosity increase or fluid solidification, when additional steam insulation folder magnetic devices, the process required to carry in the body and bonnet. Air insulation leakage of the valve in line with ANSI B16.104 standard. Jacket insulation pneumatic control valve is equipped with multi-spring diaphragm actuators, its compact structure, large output force. Products in line with GB/T4213-92