A steel bottle type of test pressure loading machine in model of ZL-1/22.5-III is a third decade of improved test pressure device. Compared with early products, its main character is taking a pneumatic clamping device and a pneumatic facility for returning water to restored position (if the user want to use a manual way for claming, it can be order to make). Overcoming the every kind of the abuses in electronic way for returning water to restored position, our products have the higher equipment reliability and a more convenience for operation. In an old way, the returning water angle and the restored position are controlled by a journey switch. Due to the inertia moment will be changed as the loading change after the motor stop, the returning water angle and the restored position are very difficult to determine and the reliability of the journey switch is low, so it is very easy to take place an accident. However the determining the returning water angle and the restored position in a pneumatic device is determined by the stroke of the cylinder, so the  returning water angle is stable and the restored position is reliable. In addition, the toppling speed of the steel bottle can be adjusted in no class by the anechoic throttle on the manual controlled valves of returning water and restoring position, which is easy and reliable.