I. General Purpose Seamless Steel Pipe
Seamless steel tube is a kind of long steel with a hollow cross-section and no welded seam around. It is perforated from the whole round steel, widely used in the transportation of fluids (such as oil, natural gas, water, etc.) and the manufacture of structural components, mechanical parts.
II. Classification of Seamless Steel Tubes
Seamless steel tubes are mainly classified according to production methods and applications:
A: Classification according to production methods:
Hot Rolled Seamless Steel Tubes: Produced by high temperature rolling process, suitable for general purposes.
Cold rolled/cold drawn seamless steel pipe: produced by cold working process, with higher dimensional accuracy and surface quality.
Extruded seamless steel pipe: suitable for the production of high-strength alloy steel pipe.
B: Classified by use:
Seamless steel pipe for structure (GB/T8162): used for general structure and mechanical structure.
Seamless steel pipe for fluid transportation (GB/T8163): used for transportation of liquids and gases.
Seamless steel pipe for boiler (GB3087, GB5310): used for manufacturing boiler pipes.
Seamless steel pipe for geological drilling (YB235): used for geological drilling.
Seamless steel pipe for petroleum cracking (GB9948): used in petroleum refining equipment.
III. Seamless steel pipe manufacturing process
Seamless steel pipe manufacturing process mainly includes the following steps:
A: raw material preparation: choose suitable billets, such as carbon steel, alloy steel or stainless steel.
B: heating and piercing: the billet is heated to a high temperature and then passed through the piercing machine to form a hollow billet.
C: Rolling:
Hot Rolling: The billet is rolled and shaped through a rolling mill at a high temperature.
Cold Rolling/Cold Drawing: Further processing by cold rolling or cold drawing at room temperature to improve dimensional accuracy and surface quality.
Heat treatment: Improve the mechanical properties of steel pipe by annealing, normalizing or quenching.
Finishing and inspection: including straightening, hydraulic test, flaw detection, etc., to ensure product quality.
IV. Application of seamless steel pipe
Seamless steel pipe is widely used in many fields because of its high strength and corrosion resistance:
A: Oil and gas: used for oil and gas transportation pipelines.
B: Construction and infrastructure: for building structures, underground pipelines.
C: Machinery manufacturing: used for manufacturing automobile drive shafts, mechanical parts.
D: Chemical industry: used for pipelines conveying corrosive media.
E: electric power industry: used for boiler piping, heat pipe.
V. Seamless steel pipe future trends
Seamless steel pipe industry will show the following future development trends:
technological innovation and product upgrading: research and development of high-performance materials and new processes to meet high-end market demand.
Environmental protection and sustainable development: driven by environmental protection policies, the industry will pay more attention to energy saving and emission reduction.
Industry Chain Integration: Enhance the overall competitiveness of the industry through the cooperation of upstream and downstream enterprises.
Internationalization expansion: With the changes in global market demand, the export of seamless steel pipes will continue to grow.