Welded steel pipes can be classified into different types and types according to different classification methods. Welded steel pipes of different properties have different characteristics and characteristics in use and show different use values in use. Welded steel pipes can be divided into the following categories according to their uses: General welded steel pipes, galvanized welded steel pipes, oxygen-blown welded steel pipes, wire casings, metric welded steel pipes, roller pipes, deep well pump pipes, automotive pipes, transformer pipes, electric welding pipes Thin-walled pipes, electric welded special-shaped pipes and spiral welded steel pipes. Different welded steel pipes have different use values and performances in use, the manufacturing processes will be different, and the national production standards that need to be followed are also different. The following is a brief introduction to the characteristics and advantages of different types and properties of welded steel pipes:
1. General welded steel pipe: General welded steel pipe is used to transport low-pressure fluid. Made of Q195A, Q215A, Q235A steel. It can also be made of other mild steels that are easily weldable. Steel pipes are subject to hydraulic pressure, bending, flattening and other experiments, and have certain requirements for surface quality. The delivery length is usually 4-10m and delivery of fixed length (or multiple lengths) is often required. The specifications of welded steel pipes are expressed in nominal diameter (millimeters or inches). The nominal diameter is different from the actual diameter. Welded steel pipes are divided into two types: ordinary steel pipes and thickened steel pipes according to the specified wall thickness. Steel pipes are divided into threaded and non-threaded ones according to the pipe end form. kind.
2. Transformer tube: used to manufacture transformer heat pipes and other heat exchangers. It is made of ordinary carbon steel and requires flattening, flaring, bending, and hydraulic testing. Steel pipes are delivered in fixed lengths or multiple lengths, and there are certain requirements for the bending of the steel pipes.
3. Special-shaped pipes: square pipes, rectangular pipes, hat-shaped pipes, hollow rubber steel pipes for doors and windows welded from ordinary carbon structural steel and 16Mn and other steel strips. They are mainly used as agricultural machinery components, steel windows and doors, etc.
4. Galvanized steel pipe: To improve the corrosion resistance of steel pipes, ordinary steel pipes (black pipes) are galvanized. Galvanized steel pipes are divided into two types: hot-dip galvanizing and electric steel zinc. Hot-dip galvanizing has a thick zinc layer and electro-galvanizing has a low cost.
5. Idler tube: Electrically welded steel pipe used for belt conveyor idlers, generally made of Q215, Q235A, B steel, and 20 steel, with a diameter of 63.5-219.0mm. There are certain requirements for the curvature of the pipe, the end face to be perpendicular to the central line, and the ovality. Generally, water pressure and flattening tests are carried out.
6. Oxygen-blowing welded steel pipe: used as a pipe for oxygen blowing in steelmaking. Generally, small-diameter welded steel pipes are used, with eight specifications ranging from 3/8 inch to 2 inch. Made of 08, 10, 15, 20, or Q195-Q235 steel strip. To prevent corrosion, some are aluminized.
7. Electrically welded thin-walled tubes: mainly used to make furniture, toys, lamps, etc. In recent years, thin-walled tubes made of stainless steel strips have been widely used in high-end furniture, decorations, fences, etc.
8. Wire casing: It is also an ordinary carbon steel electric welded steel pipe. It is used in concrete and various structural power distribution projects. The commonly used nominal diameter is from 13-76mm. The wire sleeve has a thin wall and is mostly used after being coated or galvanized, requiring a cold bending test.
9. Metric welded steel pipe: The specification is in the form of seamless pipe, and the welded steel pipe is expressed in outer diameter * wall thickness in millimeters. It is welded with tropical or cold zones of ordinary carbon steel, high-quality carbon steel, or general low alloy steel, or with hot strip welding, it is made by cold drawing method. Metric welded steel pipes are divided into general and thin-walled. They are generally used as structural parts, such as drive shafts, or to transport fluids. Thin-walled steel pipes are used to produce furniture, lamps, etc. The strength and bending test of the steel pipe must be ensured.
10. Spiral welded steel pipe: It is made by rolling low-carbon carbon structural steel or low-alloy structural steel strips into a pipe blank according to a certain spiral angle (called forming angle), and then welding the pipe seams. It can be used with Narrower strips to produce larger-diameter steel pipes. Spiral welded steel pipes are mainly used for oil and natural gas transmission pipelines, and their specifications are expressed by outer diameter * wall thickness. Spiral welded steel pipes are either single-sided or double-sided. Welded steel pipes should ensure that the hydraulic pressure test, tensile strength, and cold bending performance of the weld comply with regulations.
Different types and functions of welded steel pipes have different use ranges and environments, and their use methods in production and processing will also be different. Therefore, when using welded steel pipes, they must be used according to different situations to ensure the value of welded steel pipes in use.
Post time: Dec-22-2023