ASME B16.9 Seamless TP316 Straught Cross Pipe Branch Connection Fittings

Stainless steel crosses are divided into equal diameters and reducing diameters. The ends of the equal diameter crosses are all the same size; the main pipes of the reducing crosses have the same size, but the branch pipes are smaller than the main pipe. Stainless steel cross is a kind of pipe fittings used at pipeline branches. For the use of seamless pipes to manufacture crosses, the currently commonly used processes include hydraulic bulging and hot pressing.

1. Hydraulic bulging" Four-way hydraulic bulging is a forming process in which branch pipes are expanded by the axial compensation of metal materials. The process is to use a special hydraulic press to inject liquid into the tube blank with the same diameter as the four-way tube. The two horizontal side cylinders of the hydraulic press synchronize the centering movement to extrude the tube blank. The volume of the tube blank becomes smaller after being squeezed. The pressure of the liquid increases as the volume of the tube becomes smaller. When the pressure required for the expansion of the four-way branch tube is reached, the metal material flows along the inner cavity of the mold under the dual action of the side cylinder and the liquid pressure in the tube to expand the branch tube. The hydraulic bulging process of the four-way can be formed at one time, and the production efficiency is high; the wall thickness of the main pipe and the shoulder of the four-way are increased. Due to the large tonnage of equipment required for the hydraulic bulging process of seamless crosses, it is currently mainly used in the manufacture of standard wall thickness crosses less than DN400 in China. The applicable forming materials are low-carbon steel, low-alloy steel, and stainless steel with relatively low cold work hardening tendency, including some non-ferrous metal materials, such as copper, aluminum, and titanium.

2. Hot press forming Four-way hot press forming is to flatten a tube blank larger than the diameter of the four-way to the size of the four-way diameter, and open a hole in the stretched branch tube; the tube blank is heated and placed in the forming mold , And insert a punching die for stretching the branch pipe into the tube blank; 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 four-way, the metal of the hot-pressed four-way branch is compensated by the radial movement of the tube blank, so it is also called the radial compensation process. Because the cross is pressed after heating, the tonnage of equipment required for material forming is reduced. Hot-pressed crosses have wide adaptability to materials, and are suitable for low-carbon steel, alloy steel, and stainless steel materials; especially for crosses with large diameters and thicker walls, this forming process is usually used.

product description