Introduction to Practical Knowledge of Pipes (Part 2)

Seamless steel tube

Seamless Steel Pipe is long steel with a hollow cross-section and no joints around it. The steel pipe has a hollow cross-section, and is widely used as a pipeline for transporting fluids, such as a pipeline for transporting oil, natural gas, coal gas, water, and certain solid materials.

Compared with solid steel such as round steel, steel pipe is lighter in weight when the flexural and torsional strength is the same. It is economic cross-section steel and is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile transmission shafts, and bicycles. Frame and steel scaffold used in construction. The use of steel pipes to manufacture ring-shaped parts can improve the material utilization rate, simplify the manufacturing process, save materials and processing hours, such as rolling bearing rings, jack sleeves, etc. At present, steel pipes have been widely used for manufacturing. Steel pipes are also indispensable materials for various conventional weapons, and the barrels and barrels are all made of steel pipes.

Steel pipes can be divided into round pipes and shaped pipes according to different cross-sectional shapes. Since the circle area is the largest under the condition of equal circumference, more fluid can be transported with a round tube. In addition, when the circular cross-section is subjected to internal or external radial pressure, the force is relatively uniform. Therefore, most steel tubes are round tubes. However, the round tube also has certain limitations. For example, under the condition of flat bending, the round tube is not as strong as the square and rectangular tube. Some agricultural machinery skeletons and steel-wood furniture are commonly used. According to different uses, special-shaped steel pipes with other cross-sectional shapes are required.

1. The seamless steel pipe for structure (GB/T 8162-2008) is a seamless steel pipe for general structure and mechanical structure.

2. Seamless steel pipe for fluid transportation (GB/T 8163-2008) is a general seamless steel pipe for transporting fluids such as water, oil, and gas.

3. Seamless steel tubes for low and medium pressure boilers (GB 3087-2008) are used to manufacture superheated steam pipes, boiling water pipes for various structures of low and medium pressure boilers, superheated steam pipes, large smoke pipes, small smoke pipes and arches for locomotive boilers Hot-rolled and cold-drawn (rolled) seamless steel tubes of high-quality carbon structural steel for brick pipes.

4. Seamless steel tubes for high-pressure boilers (GB 5310-2008) are high-quality carbon steel, alloy steel, and stainless heat-resistant steel seamless tubes for the heating surface of the water tube boilers with high pressure and above pressure.

5. High-pressure seamless steel pipe for fertilizer equipment (GB 6479-2013) is a high-quality carbon structural steel and alloy steel seamless steel pipe suitable for chemical equipment and pipelines with a working temperature of -40~400℃ and working pressure of 10~30Ma. .

6. Seamless steel pipe for petroleum cracking (GB 9948-2013) is a seamless steel pipe suitable for furnace pipes, heat exchangers and pressure pipes in petroleum refineries.

Seamless Steel Pipe

7. Seamless steel pipe for geological drilling (GB/T 9808-2008) is a steel pipe used for core drilling in the geological department. It can be divided into the drill pipe, drill collar, core pipe, casing, and precipitation pipe according to the purpose.

8. Geological core drilling tools (GB/T 16950-2014) stipulate seamless steel tubes for geological core drilling tools.

9. Petroleum drilling pipe (YB 528-65) is a Tubing Seamless Steel Pipe that is thickened inside or outside the ends of petroleum drilling. There are two types of steel pipes: wire and non-wire. The wired pipe is connected by a joint, and the wire pipe is connected to the tool joint by butt welding.

10. Carbon steel and carbon-manganese steel seamless steel tubes for ships (GB/T 5312-2009) are carbon steel and carbon-manganese steel used for manufacturing Class I pressure-resistant piping systems, Class II pressure-resistant piping systems, boilers, and superheaters. Seam steel pipe. The working temperature of the carbon steel seamless steel pipe wall does not exceed 450℃, and the working temperature of alloy steel seamless steel pipe walls exceeds 450℃.

11. Seamless steel tubes for automobile half-shaft bushings (GB 3088-82) are high-quality carbon structural steel and alloy structural steel hot-rolled seamless steel tubes for manufacturing automobile half-shaft bushings and drive axle housing axle tubes.

12. High-pressure seamless steel pipe for diesel engines (GB/T 3093-2002) is a cold-drawn seamless steel pipe for manufacturing high-pressure pipes of diesel engine injection systems.

13. Precision inner diameter seamless steel tubes for hydraulic and pneumatic cylinders (GB 8713-88) are cold-drawn or cold-rolled precision seamless steel tubes with precise inner diameters for the manufacture of hydraulic and pneumatic cylinders.

14. Cold drew or cold rolled precision seamless steel pipe (GB/T 3639-2009) is a cold drawn or cold rolled precision seamless steel pipe with high dimensional accuracy and good surface finish for mechanical structures and hydraulic equipment. The use of precision seamless steel tubes to manufacture mechanical structures or hydraulic equipment, etc., can greatly save mechanical processing man-hours, improve material utilization, and at the same time help to improve product quality.

15. Stainless steel seamless steel pipe for structure (GB/T 14975-2012) is a stainless steel hot-rolled widely used in the chemical industry, petroleum, light textile, medical, food, machinery, and other industries, corrosion-resistant pipes and structural parts and parts (Extruded, expanded) and cold drawn (rolled) seamless steel tubes.

16. Stainless steel seamless steel pipe for fluid transportation (GB/T 14976-2012) is a hot-rolled (extruded, expanded) and cold drawn (rolled) seamless steel pipe made of stainless steel for fluid transportation.

17. Special-shaped seamless steel tubes are the general term for seamless steel tubes with cross-sectional shapes other than round tubes. According to the different shapes and sizes of steel tube cross-section, it can be divided into equal-thickness and irregular-shaped seamless steel pipe (code-named D), unequal-walled and shaped seamless steel pipe (code-named BD), and variable-diameter irregular-shaped seamless steel pipe (code-named BJ). Special-shaped seamless steel tubes are widely used in various structural parts, tools, and mechanical parts. Compared with round tubes, shaped tubes generally have larger moments of inertia and section modulus, and have greater bending and torsion resistance, which can greatly reduce the weight of the structure and save steel.