316L Stainless Steel Industrial Welded Pipe ClassificationCategorized by Use
The categories include general welding pipes, galvanized welding pipes, oxygen blowing welding pipes, wire sleeve pipes, metric welding pipes, roller tubes, deep well pump pipes, automotive pipes, transformer pipes, welding thin-walled pipes, welding non-standard pipes, scaffolding pipes, and spiral welding pipes.
General Welded Pipes: General welded pipes are used for conveying low-pressure fluids. Made from Q195A, Q215A steel, they can also be manufactured from other soft steels that are easy to weld. The pipes must undergo hydraulic tests, bending, flattening, and other experiments, with specific requirements for surface quality. The standard delivery length is typically 4-10 meters, often requiring fixed-length (or multiple-length) delivery. The specifications of the welded pipes are indicated by the nominal diameter (mm or inches), which may differ from the actual diameter. Welded pipes are available in two types according to the specified wall thickness: standard and thickened, and are also divided into threaded and unthreaded ends.
Galvanized Steel Pipe: To enhance the corrosion resistance of steel pipes, galvanizing is applied to ordinary steel pipes (black pipes). Galvanized steel pipes are categorized into two types: hot-dipped galvanized and electro-galvanized. Hot-dipped galvanized pipes have thicker zinc coatings, while electro-galvanized pipes are more cost-effective.
Oxygen Blowing Welded Pipe: Used for steelmaking oxygen blowing, typically made from small-diameter welded steel pipes, available in eight sizes ranging from 3/8 inch to 2 inches. Manufactured from steel strips of grades 08, 10, 15, 20, or Q195-Q235. Some are treated with aluminum alloying to prevent corrosion.
Conduit Pipes: Also known as ordinary carbon steel welded pipes, these are used in concrete and various structural electrical distribution projects, with nominal diameters commonly ranging from 13-76mm. The conduit pipe walls are relatively thin, usually coated or galvanized before use, and require cold bending tests.Metric Welded Pipe: Welded steel pipes used as seamless tubes, indicated by outer diameter * wall thickness in millimeters, are produced by hot or cold rolling welding of ordinary carbon steel, high-quality carbon steel, or general low-alloy steel. They can be hot-rolled and then cold drawn. Metric welded pipes are categorized into general-purpose and thin-walled types. They are commonly used as structural components, such as drive shafts, or for conveying fluids. Thin-walled pipes are used in the production of furniture, lighting fixtures, etc., ensuring pipe strength and bend tests.
Roller Tube: Welded steel tubes for belt conveyors, commonly made of Q215, Q235 A, B steel, and 20 steel, with diameters ranging from 63.5 to 219.0mm. The tubes must meet certain requirements for bend, end face perpendicular to the centerline, and ellipticity. They are typically tested for hydrostatic pressure and flattening.
Transformer Tubes: Used for manufacturing transformer cooling tubes and other heat exchangers, these tubes are made from plain carbon steel and require processes such as flattening, expanding, bending, and hydrostatic testing. The steel tubes are delivered in fixed or multiple lengths, with specific requirements for the degree of bending.
Special-shaped tubes: Square tubes, rectangular tubes, cap-shaped tubes, and steel pipes for hollow steel windows and doors, welded from common carbon structural steel and 16Mn steel strips, mainly used as agricultural machinery components and steel windows and doors.
Welded Thin-Walled Tubes: Primarily used in the manufacturing of furniture, toys, lighting fixtures, etc. In recent years, thin-walled tubes made of stainless steel strips have seen widespread applications in furniture, decoration, and fencing, among others.
Heliarc Welded Pipes: These pipes are manufactured by rolling low-carbon carbon structural steel or low-alloy structural steel strips into a tube blank at a specific helical angle, known as the forming angle, and then welding the tube seam. They can produce large-diameter steel pipes using narrower strips. Heliarc welded pipes are primarily used for oil and natural gas transmission pipelines, and their specifications are indicated by the outer diameter multiplied by the wall thickness. There are single-sided and double-sided welded pipes, and the pipes must ensure that the water pressure test, tensile strength of the weld seam, and cold bending properties meet the specified requirements.
Categorized by Production Methods
(1) By process type - Arc Welded Pipes, Resistance Welded Pipes (High Frequency, Low Frequency), Gas Welded Pipes, Furnace Welded Pipes.
(2) By welding seam type—Straight Seam Welded Pipe, Spiral Welded Pipe.
Categorized by cross-sectional shape
(1) Simple Seamless Steel Tubes - Round, Square, Elliptical, Triangular, Hexagonal, Diamond, Octagonal, Semi-Circular, and Others.
Complex Section Steel Tubes - Unequal Hexagonal Steel Tubes, Five-Petal Plum Steel Tubes, Double Bulge Steel Tubes, Double Concave Steel Tubes, Walnut Steel Tubes, Conical Steel Tubes, Wavy Steel Tubes, Case Steel Tubes, others.
By Wall Thickness Classification
Wall thickness steel tubes, thick-walled steel tubes.
Categorized by end shape
Circular welded pipes and non-circular (square, flat, etc.) welded pipes.