A. Hydroreforming
Three-way hydraulic bulging is to expand the forming process of branch pipe through axial compensation of metal materials. Its process is to inject liquid into the tube blank with the same diameter as the tee with a special hydraulic press, and the tube blank is extruded by two horizontal side cylinders of the hydraulic press. After extrusion, the volume of tube blank becomes smaller, and the pressure in tube blank increases with the decrease of tube blank volume. When the pressure required to expand the tee branch pipe is reached, the metal material flows along the inner cavity of the die under the dual action of the liquid pressure in the side cylinder and the tube blank, so that the branch pipe expands.
B. hot pressing forming
Hot-pressing forming of tee is to flatten the pipe blank larger than the diameter of tee to the size of the diameter of tee, and open holes in the stretched part of branch pipe; Heating the tube blank, putting the tube blank into a forming mold, and filling the tube blank with the mold to stretch the branch pipe; Under the action of pressure, the tube blank is compressed radially. In the process of radial compression, the metal flows in the direction of the branch pipe, and the branch pipe is formed under the tension of the die. The whole process is formed by radial compression of tube blank and stretching of branch tube. Different from the hydraulic bulging tee, the branch metal of the hot-pressing tee is compensated by the radial movement of the tube blank, so it is also called radial compensation process.