The characteristics of the classification of steel pipes

Posted by chase Liu on November 30th, 2022

Galvanized steel pipe: In order to improve the corrosion resistance of the steel pipe, the general black steel seamless pipe is galvanized. There are two types of galvanized steel pipes: hot-dip galvanizing and electric steel zinc. The hot-dip galvanizing layer is thicker and the cost of electric galvanizing is low.

Oxygen blowing welded pipe: It is used for steelmaking and oxygen blowing pipe. Generally, small diameter welded steel tube is used. There are eight kinds of steel pipe dimensions ranging from 3/8 inch to 2 inch. Made of 08.10.15.20 or Q195-Q235 steel strip. In order to prevent corrosion, some are aluminized.

Wire casing: It is also an ordinary carbon steel electric welded steel pipe, which is used in concrete and various structural power distribution projects. The commonly used nominal diameter is from 13-76mm. The wall of the wire casing is relatively thin, and it is mostly used after coating or galvanizing, and a cold bending test is required.

Metric welded pipe: the specification is in the form of seamless pipe, and the welded steel tube is expressed in mm of outer diameter * wall thickness. It is welded with hot or cold strips of ordinary carbon steel, high-quality carbon steel or ordinary low-alloy steel, or welded with hot spots and then cold drawn. Metric welded pipes are divided into ordinary energy and thin-walled pipes, which are generally used as structural parts, such as drive shafts, or conveying fluids, and thin-walled pipes are used to produce furniture and lamps, etc., to ensure the strength and bending test of steel pipes.

Roller tube: used for belt conveyor roller electric 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 bending degree of the pipe, the end surface should be perpendicular to the center line, and the ellipticity, and the water pressure and flattening tests are generally carried out.

Transformer tubes: used to manufacture transformer cooling tubes 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 there are certain requirements for the bending degree of steel pipes.

Special-shaped pipes: square pipes, rectangular pipes, hat-shaped pipes, steel pipes for hollow plastic steel doors and windows, which are welded by ordinary carbon-bonded structural steel and 16Mn steel strips, mainly used as agricultural machinery components, steel windows and doors, etc.

Welded thin-walled tube: 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, decoration, fences, etc.

Spiral welded pipe: It is made by rolling low-carbon carbon structural steel or low-alloy structural steel strip into a tube blank according to a certain helical angle (called forming angle), and then welding the pipe seam. It can produce large-diameter steel pipes from narrower strips. Spiral welded pipes are mainly used for oil and natural gas pipelines, and their specifications are expressed by outer diameter * wall thickness. Spiral welded pipes are single-sided welded and double-sided welded. The welded pipes should ensure that the hydraulic test, the tensile strength of the weld and the cold bending performance must meet the regulations.