Hydraulic test device for large-diameter thick-wall pipe joint

The utility model provides a hydraulic test device for a large-diameter thick-wall pipe joint. During forging of the large-diameter thick-wall pipe joint, a pipe joint lug boss is forged on the internal diameter of the pipe joint, a seal plate is welded on the lug boss, a clearance between the lug boss and the seal plate is subjected to seal welding, and as the lug boss and the pipe joint are integrated, a stronger acting force can be born, and the seal plate is prevented from dashing off due to overlarge pressure. At the moment, the welding seam only plays a sealing role, the weld bead height is far smaller than that of a traditional hydraulic test device, and the welding cost is greatly lowered. Then a hydraulic test is performed. After the hydraulic test is completed, the lug boss is cut off, and the inner wall of the pipe joint at the lug boss is machined to the designed dimension, so that the hydraulic test can be safely completed, materials are saved, the forging cost of the pipe joint and the welding c