Bearing pipe is a kind of seamless steel pipe by hot-rolled or cold-rolled ( cold drawn ), used for the manufacture of ordinary bearing rings. The outer diameter of pipe is usually  25-180 mm and with wall thickness of 3.5-20 mm. Bearing steel is used to make ball, roller and bearing rings of steel. Bearings work under immense pressure and friction, it requires a high and uniform bearing steel hardness and wear resistance, and a high elastic limit. Bearing steel chemical composition uniformity, non-metallic inclusion content and distribution, the distribution of carbides and other requirements are very stringent requirements of all steel production in one of the most demanding steel grades.

Bearing steel has a high smelting quality requirements, meanwhile, and requires strict control of sulfur, phosphorus, hydrogen content, and non-metallic inclusions and carbides of the number, size and distribution, non-metallic inclusions and carbides as the number, size and distribution service life of the bearing steel great influence, often bearing failure is in large carbide inclusions or micro-cracks generated around the extension to. Inclusions content and oxygen content in steel is closely related to the higher oxygen content, the more the number of inclusions, the shorter life expectancy. And carbide inclusions larger particle size, more uniform distribution, the shorter the service life, and their size , distribution and use of the smelting process and the smelting quality is closely related to, now bearing steel production as well as the main process is the continuous casting EAF + ESR smelting process, as well as a small amount of vacuum induction vacuum arc double vacuum or + repeatedly vacuum consumable and other technology to improve the quality of bearing steel.

Since the bearing should have a long life, high precision, low heat, high speed, high rigidity, low noise, high wear resistance and other characteristics, thus requiring the bearing pipe should have: high hardness, uniform hardness, high elastic limit, high contact fatigue strength, must toughness, hardenability must be in atmospheric corrosion resistance of the lubricant. To achieve these performance requirements, the chemical composition of steel bearings homogeneity, non-metallic inclusion content and type, size and distribution of carbides, decarburization demanding. Overall bearing steel to high-quality, high performance and multi-species direction. Bearing steel according to characteristics and application environments are divided into: high carbon chromium bearing steel, carburizing bearing steel, high temperature bearing steel, stainless steel and special bearing special bearing materials. To meet the high-temperature, high-speed, high load, corrosion, anti-radiation requirements, need to develop a series of special performance of the new bearing steel. In order to reduce the oxygen content of bearing steel, the development of vacuum smelting, electroslag remelting, electron beam remelting bearing steel smelting technology. The large quantities of bearing steel smelting by the arc melting, to develop into all types of early Canadian refining furnace.