Pressure testing machine for testing gas pressure of valves used on gas pipeline

A pressure testing machine for testing gas pressure of valves used on a gas pipeline comprises an operation platform, a top-pressing type test bench, a clamping jaw type test bench, and an air pressure supply device and an oil pressure driving device which are matched with the top-pressing type test bench and the clamping jaw type test bench respectively, the air pressure supply device and the oil pressure driving device are controlled by the operation platform, the clamping jaw type test bench comprises a clamping jaw test bench, an active clamping jaw mounted on the clamping test bench, two driven clamping jaws which act synchronously with the active clamping jaw, a push-and-pull oil cylinder located inside the clamping jaw test bench and used for pushing the active lamping jaw to move horizontally and three clamping oil cylinders used for driving corresponding active and driven clamping jaws to perform clamping action on the valves, and the push-and-pull oil cylinder and the three clamping oil cylinders ar