Hydraulic bulging technology and process of stainless steel tee
The hydraulic bulging process of stainless steel tee requires a large tonnage of equipment. At present, it is mainly used in the manufacture of stainless steel tee with standard wall thickness less than DN400 in China. The hydraulic bulging process of stainless steel tee can be formed at one time, and the production efficiency is high. Hydraulic bulging is a forming process in which branch pipes are expanded by axial compensation of metal materials.
The hydraulic bulging process of the stainless steel tee uses a special hydraulic press to inject liquid into the tube blank with the same diameter as the stainless steel tee, and the tube blank is squeezed by the two horizontal side cylinders of the hydraulic press. After the volume becomes smaller, the liquid in the tube billet will increase in pressure as the tube billet volume becomes smaller. When the pressure required for the expansion of the stainless steel three-way branch tube is reached, the metal material will flow under the dual action of the side cylinder and the liquid pressure in the tube billet. The inner cavity of the mold flows and expands out of the branch pipe. The wall thickness of the main pipe and the shoulder of the stainless steel tee are increased.
The forming of a stainless steel tee joint is to flatten a tube blank larger than the diameter of the tee to the size of the diameter of the stainless steel tee, and open a hole in the stretched branch tube; the tube blank is heated, placed in the forming die, and placed in the tube. The blank is loaded with a punching die for stretching the branch tube; the tube blank is radially compressed under the action of pressure, and the metal flows in the direction of the branch tube during the radial compression process and forms a branch tube under the stretching of the die. The whole process is formed by the radial compression of the tube blank and the stretching process of the branch tube. Different from the hydraulic bulging tee, the metal of the branch pipe of the tee joint is compensated by the radial movement of the tube blank, so it is also called the radial compensation process.
As the tee is pressed after heating, the equipment tonnage required for material forming is reduced. Hot-pressed tee has a wide adaptability to materials, and is suitable for low-carbon steel, alloy steel, and stainless steel; especially for tee with large diameter and thicker wall, this forming process is usually used.