Description

Oblique tees are classified into 15° oblique tees, 30° oblique tees, 45° oblique tees, 60° oblique tees, reducing oblique tees, tapered oblique tees, special-shaped tees, and arbitrary-angle oblique tees. They are tee pipe fittings where the branch pipe forms a certain included angle with the main pipe, manufactured from seamless pipes. At present, two processes are widely used: hydraulic bulging and hot press forming.

a. Hydraulic Bulging
Hydraulic bulging is a forming process that bulges out the branch pipe through axial compensation of metal materials. The process involves injecting liquid into a pipe blank with the same diameter as the tee using a dedicated hydraulic press. Two horizontal side cylinders of the hydraulic press squeeze the pipe blank through synchronous centering movement. The volume of the pipe blank decreases under extrusion, and the pressure of the liquid inside the pipe blank rises as its volume shrinks. When the pressure required for bulging out the tee branch pipe is reached, the metal material flows along the mold cavity under the combined action of the side cylinder and the liquid pressure inside the pipe blank to form the branch pipe.

b. Hot Press Forming
Hot press forming involves flattening a pipe blank larger than the tee diameter down to approximately the tee diameter size, and drilling a hole at the position where the branch pipe will be stretched. The pipe blank is heated, placed into a forming mold, and a punch for stretching the branch pipe is installed inside the pipe blank. Under pressure, the pipe blank is radially compressed; during radial compression, the metal flows toward the branch pipe and forms the branch pipe under the stretching of the punch. The entire forming process is completed through radial compression of the pipe blank and stretching of the branch pipe section. Unlike hydraulically bulged tees, the metal for the branch pipe of hot-pressed tees is compensated by the radial movement of the pipe blank, hence this process is also known as the radial compensation process.

Our company specializes in producing national standard tees, non-standard tees, special-shaped tees, American standard tees, German standard tees, etc., as well as various carbon steel straight seam seamless tees, straight seam tees, and thick-walled tees.

In addition, our factory can design and manufacture various complex and special tee pipe fittings, equal-diameter oblique tees and reducing oblique tees of any angle. Available materials include carbon steel, Q235, No.20 steel, A105, 16Mn and so on.