Welded steel pipes can be classified into different types and categories according to different classification methods. Welded steel pipes of different properties have different characteristics and properties in use and show different use values in use. Welded steel pipes can be classified into the following categories according to their use: 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, automobile pipes, transformer pipes, electric welded thin-walled pipes, electric welded special-shaped pipes and spiral welded steel pipes. Different welded steel pipes show different use values and functions in use, and the manufacturing process will also be different. The national production standards that need to be followed are also different. The following is a brief introduction to the characteristics and advantages of welded steel pipes of different types and properties:
General welded steel pipes: General welded steel pipes are used to transport low-pressure fluids. Made of Q195A, Q215A, and Q235A steel. It can also be made of other soft steels that are easy to weld. Steel pipes must undergo water pressure, bending, flattening, and other tests, and have certain requirements for surface quality. Usually, the delivery length is 4-10m, and it is often required to be delivered in a fixed length (or multiple lengths). The specifications of welded steel pipes are expressed in nominal diameter (mm or inches). The nominal diameter is different from the actual diameter. Welded steel pipes are divided into ordinary steel pipes and thickened steel pipes according to the designated wall thickness. Steel pipes are divided into threaded and non-threaded according to the form of the pipe ends.
Transformer pipe: used to manufacture transformer heat dissipation pipes and other heat exchangers, made of ordinary carbon steel, requiring flattening, flaring, bending, and hydraulic tests. Steel pipes are delivered in fixed length or multiple lengths, and have certain requirements for the curvature of steel pipes.
Special-shaped steel pipes: square steel pipes, rectangular steel pipes, cap-shaped steel pipes, and steel pipes for hollow rubber steel doors and windows welded from ordinary carbon structural steel and 16Mn steel strips, mainly used as agricultural machinery components, steel windows, doors, etc.
Galvanized steel pipe: To improve the corrosion resistance of steel pipe, ordinary steel pipe (black pipe) is galvanized. Galvanized steel pipe is divided into hot-dip galvanizing and electric galvanizing. Hot-dip galvanizing has a thick galvanizing layer and a low cost of electric galvanizing.
Roller pipe: Used for belt conveyor roller welded steel pipe, 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 must be perpendicular to the center line, and the ovality. Generally, water pressure and flattening tests are carried out.
Oxygen blowing welded steel pipe: Used as oxygen blowing pipe for steelmaking, generally small-diameter welded steel pipe is used, and the specifications are from 3/8 inch to 2 inches. Made of 08, 10, 15, 20, or Q195-Q235 steel strip. For corrosion protection, some are treated with aluminum.
Electric welded thin-walled steel pipe: Mainly used to make furniture, toys, lamps, etc. In recent years, thin-walled steel pipes made of stainless steel strips have been widely used, such as high-end furniture, decorations, fences, etc.
Wire sleeve: It is also an ordinary carbon steel electric welded steel pipe, used in concrete and various structural power distribution projects, with a common nominal diameter ranging from 13-76mm. The wall of the wire sleeve is thinner, and most of them are used after coating or galvanizing, and cold bending tests are required.
Metric welded steel pipe: The specification is in the form of a seamless steel pipe, and the welded steel pipe is expressed by outer diameter * wall thickness in millimeters. It is made by hot strip welding, cold strip welding of ordinary carbon steel, high-quality carbon steel, or ordinary low-alloy steel, or by hot strip welding and then cold drawing. Metric welded steel pipes are divided into ordinary and thin-walled and are generally used as structural parts, such as transmission shafts, or conveying fluids. Thin-walled is used to produce furniture, lamps, etc., and the strength and bending tests of steel pipes must be guaranteed.
Spiral welded steel pipe: It is made by rolling low-carbon carbon structural steel or low-alloy structural steel strips into a tube blank at a certain spiral angle (called forming angle), and then welding the tube seam. It can produce large-diameter steel pipes with narrower strip steel. Spiral welded steel pipes are mainly used for oil and natural gas pipelines, and their specifications are expressed by outer diameter * wall thickness. Spiral welded steel pipes are single-sided welded and double-sided welded. Welded steel pipes should ensure that the water pressure test, tensile strength of the weld, and cold bending performance meet the regulations.
Different types and functions of welded steel pipes have different use ranges and environments, and the methods of use in production and processing will also be different. Therefore, when using welded steel pipes, they should be used according to different situations to ensure the value of welded steel pipes in use.
Post time: Dec-20-2024