1. Seamless steel pipe is made of steel ingot or solid tube blank which is perforated and then hot rolled, cold rolled or cold drawn. Seamless steel pipe has a hollow cross section and is widely used as a pipeline for conveying fluid. Compared with solid steel such as round steel, steel pipe is lighter under the same bending and torsion strength. It is an economical section steel, which is widely used to manufacture structural parts and mechanical parts, such as steel scaffolding of oil drilling rig.
Second, the characteristics of seamless steel pipe:
1. The thicker the wall thickness of the product, the more economical and practical it is. The thinner the wall thickness, the higher the processing cost.
2. The technology of this product determines its limited performance. Generally, the precision of seamless steel pipe is low: uneven wall thickness, low brightness inside and outside the pipe, high cost of length, and difficult removal of internal and external pits and black spots;
3. Its detection and shaping must be done off-line. Therefore, it shows its advantages in high pressure, high strength and mechanical structure materials.
Extended data:
Application of seamless steel pipe;
1, bearing steel tube (Yb/Z 12-77): It is mainly used for manufacturing rolling bearing rings.
2. Cold-drawn precision welded pipe: mainly used for bicycle pipes.
3. Hydraulic prop pipe: mainly used for manufacturing hydraulic prop, lifting prop and inner cylinder of hydraulic cylinder for coal mine.
4. Seamless Carbon Steel Pipe for Ships (GB/T 5312—1999):1and 2 are mainly used for pressure pipes of ships.
5. Cold-rolled Seamless Special-shaped Steel Pipe (GB/T 3094-1999): It is mainly used for manufacturing general structural parts.
6. Seamless Steel Pipe for Conveying Fluid (GB/T8 163— 1999): It is mainly used for conveying pipelines. For example: central air conditioning, cold storage, gas, fire engineering, etc.
7. Seamless Steel Pipe with Precise Inner Diameter for Hydraulic and Pneumatic Cylinder (GB/T87 13— 1988): It is mainly used to manufacture fittings with high internal and external surface roughness and accurate internal and external dimensions, such as hydraulic and pneumatic cylinders. For example: jack, shock absorber, motor housing, cylinder, injection molding machine, etc.
8. Seamless Steel Pipe for Structure (GB/T8 162— 1999): It is mainly used for general structures and mechanical structures.
9. Seamless Steel Pipe for Medium and Low Pressure Boilers (GB 3087- 1999): It is mainly suitable for superheated steam pipes and boiling water pipes with pressure heating.
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