Simple structure,small volume and light weight,low cost,pneumatic butterfly valve of the notable features in-stalled in the upper passage,pneumatic valve through the two position three way solenoid valve control easy to operate,can also regulate the flow of medium.Small fluid resistance.Large diameter pneumatic butterfly valve fully open when the effective flow area is large,open and close rapidly and the disc is rotated 90 degrees to complete the opening and closing,the shaft on both sides of the disc medium force is nearly equal,the direction of torque generated instead of pneumatic butterfly valve and the opening and closing torque is small,can achieve a good seal under low pressure pneumatic butterfly valve sealing material nitrile rubber,fluorine rubber,edible rubber,PTFE is good sealing performance,no matter at low temperature,both with excellent sealing performance.