Seamless pipe manufacturing process
Seamless pipe is the strongest of all pipe types because it has a homogeneous structure over the entire length of the pipe.
Seamless pipe can be manufactured with very accurate dimensions and schedules. However, there are restrictions on the fabrication of large diameter pipes. Seamless pipe is widely used in the manufacture of pipe fittings such as elbows, bends, and tees.
Details of various manufacturing processes.
Mandrel Mill Process
In the Mandrel Mill pipe manufacturing process, the steel billet is heated to high temperature in the rotary furnace. A cylindrical hollow, which is also known as mother hollow, is produced with the help of a rotary piercer and set of roller arrangement that keeps the piercer at the center of the billet.
The outside diameter of the piercer is approximately that of the inside diameter of the finished pipe. With the help, secondary roller arrangement outside diameter and thickness are achieved.
Mannesmann Plug Mill Pipe Manufacturing Process
Mannesmann was a German engineer who has invented this pipe manufacturing process. The only difference between the Plug mill process and the Mandrel mill process is that in the mandrel method inside diameter is achieved in a single pass whereas in Mannesmann multi-stage reduction is possible.
Forged seamless pipe manufacturing process
In the forged pipeline manufacturing process, a heated billet is placed in a forging die with a diameter slightly larger than the finished pipe. Cylindrical forgings are made using a forging hammer hydraulic press with matching inside diameters.
Once the forging is complete, the pipe is machined to its final size. The forged pipe manufacturing process is used to make large diameter seamless pipe that cannot be made by conventional methods. Forged pipe is commonly used for steam manifolds.
In extruded pipe manufacturing, a heated billet is placed inside a die. A hydraulic cylinder pushes the billet tow