... Double/Single acting 3. Small torque Pneumatic control valve regulating butterfly valve ♦ Pneumatic control valve regulating butterfly valve, the valve disc and seal ring adopt unique midline ... , oil liquid, air, gas, natural gas andwater vapor, and other media to cut-off or adjust flow control. 1) On-off ... 't Hesitate to mail me or leave a message here for me, I will contact you as soon as possible, ...