Classification and use of
seamless steel pipe
The
seamless steel pipe is made by perforating the whole round steel, and the steel pipe without weld seam on the surface is called seamless steel pipe. According to the production method,
seamless steel pipes can be divided into hot-rolled seamless steel pipes, cold-rolled seamless steel pipes, cold-drawn
seamless steel pipes, extruded seamless steel pipes, and pipe jacking. According to the cross-sectional shape, seamless steel tubes are divided into two types: round and special-shaped, and special-shaped tubes have various complex shapes such as square, oval, triangular, hexagonal, melon-shaped, star-shaped, and finned tubes. The maximum diameter is up to 900mm and the minimum diameter is 4mm. According to different uses, there are thick-walled seamless steel pipes and thin-walled seamless steel pipes. Seamless steel pipes are mainly used as petroleum geological drilling pipes, cracking pipes for petrochemical industry, boiler pipes, bearing pipes, and high-precision structural steel pipes for automobiles, tractors, and aviation.
Classification
A steel pipe that is seamless along the perimeter of its cross-section. According to different production methods, it is divided into hot-rolled pipe, cold-rolled pipe, cold-drawn pipe, extruded pipe, pipe jacking, etc., all of which have their own process regulations.
The materials include ordinary and high-quality carbon structural steel (Q215-A~Q275-A and No. 10~50 steel), low alloy steel (09MnV, 16Mn, etc.), alloy steel, stainless acid-resistant steel, etc.
According to the purpose, it is divided into two categories: general purpose (for water, gas pipelines and structural parts, mechanical parts) and special purpose (for boilers, geological exploration, bearings, acid resistance, etc.).
Seamless steel pipes are widely used.
General purpose seamless steel tubes are rolled from ordinary carbon structural steels, low alloy structural steels or alloy structural steels with the highest yield, and are mainly used as pipes or structural parts for conveying fluids.
According to different purposes, there are three types of supply:
a. Supply according to chemical composition and mechanical properties;
b. Supply according to mechanical properties;
c. Supply according to hydraulic test. Steel pipes supplied by Types a and b, if used to withstand liquid pressure, are also subject to hydrostatic testing.
Special-purpose seamless pipes include seamless pipes for boilers, seamless pipes for chemical power, seamless steel pipes for geological use, and seamless pipes for petroleum.
seamless steel pipes have a hollow cross-section and are widely used as pipes for transporting fluids, such as pipes for transporting oil, natural gas, gas, water, and certain solid materials. Compared with solid steel such as round steel, the steel pipe is lighter in weight when the bending and torsional strength is the same, and it is an economical section steel.
Widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile drive shafts, bicycle frames, and steel scaffolds used in construction, etc. Steel pipes are used to make ring parts, which can improve material utilization, simplify manufacturing processes, and save materials and processing Man-hours have been widely used to manufacture steel pipes.
