The development of rolling technology of seamless tube

1.Ehrhardt tube rolling process
Erhard invented the hydraulic punching process in 1891 to produce punched cup billets, and in 1899 completed the method of pushing punched billets through a series of rings of tapering diameter with a mandrel to produce seamless steel tubes . Also known as the pipe jacking process. Today, the extra-large diameter seamless pipe is still produced by the pipe jacking method, and the maximum diameter can reach 1066mm.

2.Automatic tube rolling process
After Stiefel obtained the patent of the disc piercing machine in 1895, the first automatic pipe rolling mill was put into operation in the United States in 1903. In 1905, the automatic pipe rolling line with the uniform machine was born. The automatic tube rolling mill is also called the Stiefel tube rolling mill. After that, the automatic pipe rolling mill once became the main unit for the production of seamless steel pipes.

3.Diesel tube rolling process and Accu Roll tube rolling process
Sam Diescher first conceived the idea of introducing the rotating guide plate into the two-high skew rolling mill instead of the original guide plate for extending the tube, and in 1932 the first Diescher tube mill was born. Half a century later, the American AS company first introduced the tapered roll into the skew rolling mill and obtained a patent

4.Three-roll tube rolling process
This is a three-roll cross-rolling process, in which the capillary is rolled and extended between the mandrel and three rolls. The three-roll mill is also known as the Assel mill.

5.Hot extrusion tube process
Long before the Mannesmann Brothers invented the cross-rolled piercing, there were patents for the production of seamless steel tubes using the process of hot extrusion of aluminum. But it was only after the successful adoption of glass lubricants in the 1950s that the hot extrusion process of steel pipes gained real application and rapid development. The modern hot extruded steel pipe process is mainly used for the production of high-alloy hard-to-deform pipes and special-shaped pipes.

6.Continuous tube rolling process
As early as 1891, the Kellogg steel pipe factory in the United States has obtained a patent for a continuous rolling mill. However, for a number of technical reasons, this process has not been a real success. It was not until the 1950s that this process achieved great development, and gradually became the leading rolling mill for the production of seamless steel pipes with its high capacity, high efficiency and high quality.

7.Cold drawn (rolled) tube process
The cold drawing process has been used for the secondary processing of welded pipes long before the hot-rolled seamless steel pipe production method was adopted. The cold rolling process was patented by the American Tabl Reduing Company in 1931. It adopts a deformation process similar to that of a periodic tube rolling mill (reciprocating motion of the stand, multi-pass deformation), so it is also called a cold pilger tube rolling mill.

8.Thermal expansion process
The thermal expansion process is the main method for the production of large-diameter seamless steel tubes. The maximum diameter of the roller expansion pipe expansion can reach 1500mm, which is suitable for large-scale production; while the push type pipe expansion equipment is simple, the investment is low, and the output is low, and it is only suitable for small batch production.

Author
Chase Liu