Welding tightness detection machine and method using detection machine to detect welding tightness

The invention relates to a welding tightness detection machine. The welding tightness detection machine comprises a work table, a liquid container which is arranged at the lower part of the work table, a workpiece placing tooling, a vertical movement device which is connected with the workpiece placing tooling and drives the workpiece placing tooling to vertically move to enable the workpiece placing tooling to lift together with a workpiece to come into or out of a container, a sealing positioning device which is arranged at the upper part of the workpiece placing tooling, a workpiece rotation device, a pressurizing mechanism which is arranged on the workpiece placing tooling, and a control device which is in communication connection with the vertical movement device, the sealing positioning device and the pressurizing mechanism. The invention further discloses a method using the detection machine to detect welding tightness. Through a first cylinder and a second cylinder, the welding tightness detection machine realizes the whole processes of workpiece clamping and positioning and tightness detection. The whole device has the advantages of simple structure, reliable work and simple process, and is particularly suitable for the tightness detection of a cylinder, a fuel tank, a welding pipe and the like.