AT475 Leaktightness Tester for Piping System Joint is used to test the leaktightness/sealability of elastomeric-sealing-ring-type socket joints that match PVC, polyethylene, polypropylene and other plastic pipes. Experimental data can be stored in the U disk, which can store a large amount of data, and data files can be opened with office software. It is equipped with a hydraulic pipe radial deformation device, digital display size deformation monitoring, and automatic dynamic zeroing. The operator can apply pressure to thick-walled pipes easily and effortlessly. It features an industrial color touch screen, with a test pressure arbitrarily settable between 0-0.08Mpa, programmable pressure control, allowing easy detection of data and providing a rich time-pressure curve. Pipes of different specifications are equipped with corresponding blocks, making the operation more simple and clear. The deflection angle can be arbitrarily deflected in four directions: up, down, left and right. To facilitate the installation of larger diameter samples, the specimen clamping device adopts an upper cover opening structure.