1. The pneumatic proportional control valve adopts a balanced structure. The pressure difference between the medium behind the valve and the valve has a small unbalanced force on the valve disc. The same type of valve requires a small actuator thrust under the same working conditions, so its valve stem diameter is smaller than the design or selection of a single-seat unbalanced valve.
2 The friction between the valve stem and the packing is relatively small, which reduces the resistance of the valve movement, and the wear of the valve stem and the packing is small, which increases the service life. In addition, the valve stem with a smaller diameter has a small change in thermal expansion and contraction under medium and high temperatures, which avoids the blockage caused by increased friction between the valve stem and the packing or mutual clasping.
3 Since the new sleeve valve is a balanced structure, compared with the unbalanced straight single-seat valve, the configuration of the actuator can be relatively small, but it can overcome the medium pressure difference than the straight single regulating valve. For example, the new sleeve control valve for DN200/DN250 and DN300 can be equipped with a cylinder actuator to adapt to a wide range of working pressure differences. The maximum valve seat diameter allows a working pressure difference that is about twice that of a straight-through single-seat regulating valve with the same configuration. It can also be equipped with a diaphragm actuator and an explosion-proof electric actuator.