A steel pipe with no joints on the outer surface made of a single piece of metal is called a seamless steel pipe
. According to the production method, the seamless pipe is divided into a hot rolled pipe, a cold rolled pipe, a cold drawn pipe, an extruded pipe, a top pipe, and the like. According to the shape of the section, the seamless steel tube is divided into two types: a circular shape and a special shape. The shaped tube has a plurality of complicated shapes such as a square shape, an elliptical shape, a triangular shape, a hexagonal shape, a melon shape, a star shape, and a winged tube. The maximum diameter is 650mm and the minimum diameter is 0.3mm. Depending on the application, there are thick-walled tubes and thin-walled tubes. Seamless steel pipes are mainly used as petroleum geological drilling pipes, cracking pipes for petrochemicals, boiler tubes, bearing tubes, and high-precision structural steel tubes for automobiles, tractors, and aviation.
Classification: Jointless steel pipes along the perimeter of their cross section. According to different production methods, it is divided into hot-rolled pipe, cold-rolled pipe, cold-drawn pipe, extruded pipe, and top pipe, etc., each with its own process regulations. The material is ordinary and high-quality carbon structural steel (Q215-A Q275-A and 1050 steel) low alloy steel (09MnV16Mn, etc.) alloy steel, stainless acid-resistant steel. Divided into general use for water, gas pipelines and structural parts, mechanical parts) and dedicated for boilers, geological exploration, bearings, acid resistance, etc.
Uses: Seamless steel pipe is widely used.
1. The general-purpose seamless steel pipe is rolled from ordinary carbon structural steel, low-alloy structural steel or alloy structural steel, and has the largest output, and is mainly used as a pipe or structural component for conveying fluid.
2. According to the use of three types of supply: according to chemical composition and mechanical properties; b according to mechanical properties; according to water pressure test supply. Steel pipes supplied in accordance with class ab are also subjected to hydrostatic tests if they are used to accept liquid pressure.
3. Special-purpose seamless pipes include boiler seamless pipes, chemical power, geological seamless steel pipes and petroleum seamless pipes.
Seamless steel tubes have a hollow section and are used as a large number of pipes for conveying fluids, such as pipes for transporting oil, natural gas, gas, water and certain solid materials, as well as spiral submerged arc welded pipes
. Compared with solid steel such as round steel, the steel pipe has the same bending and torsional strength, and is light in weight, and is an economical section.
Widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automotive drive shafts, bicycle frames and steel scaffolding used in construction, etc. The use of steel pipes to manufacture ring parts can improve data utilization, simplify manufacturing processes, save data and processing. In working hours, steel pipes have been widely used for manufacturing.