The seamless steel pipe is formed by perforating a steel ingot or a solid tube blank, and then hot rolled, cold rolled or cold drawn. The specifications of the seamless pipe are expressed by the outer diameter X wall thickness and millimeter number. Seamless steel tubes are divided into two types: hot rolled and cold rolled (dial) seamless steel tubes.
Seamless steel tubes have hollow sections and are used in large quantities as pipes for transporting fluids, such as pipes for transporting petroleum, natural gas, gas, water and certain solid materials. Compared with solid steel such as round steel, the steel pipe has a lighter weight when it has the same bending and torsional strength, and is an economical section steel.
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 material utilization, simplify manufacturing processes, save materials and processing. In working hours, steel pipes have been widely used for manufacturing.
The following examples illustrate the use of several seamless steel pipes:
1. Seamless steel pipe for structure: seamless steel pipe for general structure and mechanical structure.
2. Seamless steel pipe for fluid transportation: it is used to transport general seamless steel pipes in fluids such as water, oil and gas.
3. Seamless steel tubes for low and medium pressure boilers: used for the manufacture of superheated steam pipes, boiling water pipes and locomotive boiler superheated steam pipes, large smoke pipes and small smoke pipes for various structures.
4. Seamless steel pipe for high-pressure boiler: high-quality carbon steel, alloy steel and stainless steel heat-resistant steel seamless pipe for heating surface of water tube boiler for high pressure and above.
5. High-pressure seamless steel pipe for fertilizer equipment: It is suitable for high-quality carbon structural steel and alloy steel seamless steel pipe for chemical equipment and pipeline with working temperature of 40~400°C and working pressure of 10-30Ma.
6. Seamless steel pipe for petroleum cracking: suitable for furnace tubes, heat exchangers and pipeline seamless steel pipes in petroleum refineries.
7. Steel pipe for geological drilling: Steel pipes used for core drilling by the geological department can be divided into drill pipe, drill collar, core pipe, casing and sedimentation pipe according to the application.
8. Seamless steel pipe for diamond core drilling: seamless steel pipe for drill pipe, core rod and casing used for diamond core drilling.