There is no spring in the double acting cylinder, and there is no air to turn on and off (or add air from the air circuit to turn on and off). The valve position remains unchanged in case of failure. There is a spring in the single acting cylinder. There must be a choice of air on or air off. This is for safety.

In terms of function, both single acting and double acting cylinders can meet the requirements of fault opening, fault closing and fault holding. The selection of single acting and double acting depends on your site requirements. The single acting actuator is larger and heavier than the double acting actuator, so the required installation space is larger. However, the operation accuracy of single acting cylinder is higher than that of double acting cylinder, and the insurance degree of fault location is also higher. On the market, the single acting cylinder is twice as expensive as the double acting cylinder.

Single (double) action pneumatic valve (ball valve) body channel and connecting pipe diameter equal and into a diameter, the medium can almost no loss of flow. The products are usually used in the occasions with strict sealing requirements. In addition to controlling gas, liquid and steam media, they are also suitable for controlling sewage and media containing fibrous impurities. They are widely used in petroleum, chemical industry, metallurgy, light industry, paper making, power station, refrigeration and other fields.