Bearing steel tube production of the following types of bearing steel (marked with "rolling" G) : chromium bearing steel such as GCr6, GCr9 (SiMn), GCrl5 (SiMn); Chrome-free bearing steel such as GSiMnV (Re), GSiMnMoV (Re), GMnMoV (Re); Carburized bearing steel such as G20CrMo, G20Cr2Mn2Mo; High carbon chromium stainless bearing steel such as 9Cr18 (Mo) etc.
High demand for quality of bearing steel smelting, sulfur, phosphorus, and hydrogen content must be strictly controlled, and the number of non-metallic inclusions and carbide, size and distribution, because the number of non-metallic inclusions and carbide, size and distribution had a great influence on the service life of bearing steel, bearing failure is often around the large inclusions or carbide produced by micro crack propagation.
The content of inclusions is closely related to the oxygen content in steel. The higher the oxygen content, the more inclusions and the shorter the life span. Inclusions and carbide particle size and distribution is uneven, the greater the shorter service life also, and their size, distribution and use of smelting smelting process and is closely related to the quality, now the production of bearing steel is the main process of continuous casting and smelting electric furnace + esr process of smelting, and a small amount of the use of vacuum induction + vacuum consumable double process such as vacuum consumable or + many times to improve the quality of bearing steel.
Generally, if the diameter is less than 20mm, the goods shall be packed and delivered. If the diameter is larger than 20mm, the goods can be delivered naked. Specific pack requirement, inspect the contract requirement that both sides signs and decide, be like, hexagon pack, length is poor, exit should add outer packing commonly.
Cold drawn steel should be coated with anti-rust oil, some domestic manufacturers need goods, can not prevent rust, otherwise its processing into a ring when doing in addition to oil treatment. Before leaving the factory, the goods shall be accompanied with quality guarantee certificate, indicating steel number, furnace number, weight, specification, chemical composition, inspection standard and inspection result, etc.