The spiral tube is divided into two types: hot rolling and cold rolling (dial) spiral tubes. Hot-rolled spiral pipes are divided into general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, geological steel pipes and other steel pipes.
Cold-rolled (dial) spiral pipe is divided into general steel pipe, low and medium pressure boiler steel pipe, high pressure boiler steel pipe, alloy steel pipe, stainless steel pipe, petroleum cracking pipe, other steel pipes, and also includes carbon thin-walled steel pipe, alloy thin-walled steel pipe, Rust thin-walled steel pipe, special-shaped steel pipe. The outer diameter of hot-rolled seamless pipe is generally larger than 32mm, the wall thickness is 2.5-75mm, the diameter of cold-rolled spiral pipe can be 6mm, the wall thickness can be 0.25mm, the outer diameter of thin-walled pipe can be 5mm, the wall thickness is less than 0.25mm, cold Rolling is more accurate than hot rolling.
Generally used spiral submerged arc welded steel pipe: it is made of 10, 20, 30, 35, 45 and other high-quality carbon steel such as 16Mn, 5MnV and other low-alloy structural steel or 40Cr, 30CrMnSi, 45Mn2, 40MnB and other alloy steel hot-rolled or cold-rolled. of. Seamless pipes made of low carbon steel such as 10 and 20 are mainly used for fluid conveying pipes. 45, 40Cr and other medium carbon steel seamless steel pipe is used to manufacture mechanical parts, such as the force parts of automobiles and tractors. Generally, the spiral tube is required to ensure the strength and flattening test. The hot rolled steel pipe is delivered in a hot rolled state or a heat treated state; the cold rolling is delivered in a heat treated state.
Spiral tubes for low and medium pressure boilers: used in the manufacture of various low and medium pressure boilers, superheated steam pipes, boiling water pipes, water wall pipes and superheated steam pipes for locomotive boilers, large smoke pipes, small smoke pipes and arch brick pipes. Hot-rolled or cold-rolled (dial) spiral tubes of high-quality carbon structural steel. It is mainly made of steel No. 10 and No. 20. In addition to ensuring chemical composition and mechanical properties, it is required to carry out hydraulic test, crimping, flaring and flattening. Hot rolling is delivered in a hot rolled state, and cold rolled (dial) is delivered in a heat treated state.