A pipe production process in which a heated solid ingot is rolled into a hollow pipe body with no seams around the perimeter. The hot rolling method can be used to produce carbon steel, alloy pipes, high alloy steel and some non-ferrous metal seamless pipes, with an outer diameter ranging from 16 to 1600mm and a wall thickness of 2 to 200mm.
A pipe production process in which a heated solid ingot is rolled into a hollow pipe body with no seams around the perimeter. The hot rolling method can be used to produce carbon steel, alloy pipes, high alloy steel and some non-ferrous metal
seamless pipes, with an outer diameter ranging from 16 to 1600mm and a wall thickness of 2 to 200mm.
In addition to round cross-section pipes, there are also various special-shaped cross-section pipes and variable-section pipes. In addition to being used as finished pipes, hot-rolled seamless pipes can also be used as pipe materials for cold-drawn and cold-rolled pipes (see cold-rolled and cold-drawn pipes). Seamless pipes produced by hot rolling account for 80% to 90% of seamless pipe production.
The technological process of modern hot-rolled pipes is:
The tube blanks used for hot-rolled pipes include ingots, continuous cast billets, rolled billets, forged billets and hollow cast billets. The basic process of hot-rolled pipes is: (1) Pierce the ingot or billet into a hollow thick-walled capillary tube on a punching machine. The methods of piercing the tube blank are divided into two-roll cross-rolling piercing, pressure piercing, push-rolling piercing, three-roller cross-rolling piercing, etc. (2) Thin the capillary tube on the stretching machine and extend it into a raw tube with a wall thickness close to that of the finished tube. The methods of capillary tube extension or capillary tube rolling include: automatic tube rolling machine, continuous tube rolling machine, three-roller and two-roller cross-rolling (see pipe material rolling extension), periodic tube rolling machine, Pipe jacking machine. (3) Raw pipes are finely rolled into finished pipes on the finishing mill. Finish rolling of raw pipes includes pipe leveling and pipe sizing for the purpose of improving quality, as well as pipe diameter reduction and pipe thermal expansion for the purpose of expanding product specifications.
The units for producing hot-rolled seamless pipes can vary depending on the production methods and equipment used in the three basic processes of piercing, stretching and finishing rolling. Different units are named after the rolling mill that extends the capillary tube into raw tube. For example, if there is an automatic pipe rolling machine, it is called an automatic pipe rolling unit, if there is a continuous pipe rolling machine, it is called a continuous pipe rolling unit, and if the raw tube is rolled on a three-roller (or two-roller) cross-rolling stretcher, it is called a three-roller (or two-roller) unit. The pipe rolling unit is called a periodic pipe rolling unit that uses a periodic pipe rolling machine to roll pipes, and a CPE pipe jacking machine that uses a CPE pipe jacking machine to jack the pipes is called a CPE pipe jacking unit.
