Spiral Seamless Welded Pipe

Classified by purpose
It is divided into general welded pipe, galvanized welded pipe, oxygen-blowing welded pipe, wire casing, metric welded pipe, roller pipe, deep well pump pipe, automobile pipe, transformer pipe, electric welded thin-walled pipe, electric welded special-shaped pipe, scaffolding pipe and spiral welded pipe .

General welded pipe: General welded pipe is used to transport low-pressure fluid. Made of Q195A, Q215A, Q235A steel. It can also be made of other mild steel that is easy to weld. Steel pipes need to be subjected to water pressure, bending, flattening and other experiments, and there are certain requirements on the surface quality. Usually the delivery length is 4-10m, and the fixed-length (or double-length) delivery is often required. The specifications of welded pipes are expressed by the nominal diameter (mm or inches). The nominal diameter of welded pipes is different from the actual ones. According to the specified wall thickness, the welded pipes are available in ordinary steel pipes and thickened steel pipes. The steel pipes are divided into two types with thread and without thread according to the tube end form.

Galvanized steel pipe: In order to improve the corrosion resistance of the steel pipe, the general steel pipe (black pipe) is galvanized. Galvanized steel pipes are divided into two types: hot-dip galvanizing and electro-galvanizing. The hot-dip galvanizing layer is thick and the cost of electro-galvanizing is low.

Oxygen-blowing welded pipe: Used as a steel-making oxygen-blowing pipe, generally small-diameter welded steel pipes are used, with eight specifications ranging from 3/8 inch to 2 inch. It is made of 08, 10, 15, 20 or Q195-Q235 steel belt. In order to prevent corrosion, some are aluminized.

Wire casing: Ordinary carbon steel electric welded steel pipe, used in concrete and various structural power distribution projects, the commonly used nominal diameter is from 13-76mm. The wall of the wire sleeve is thin, and most of it is used after coating or galvanizing, and a cold bend test is required.

Metric welded pipe: The specification is used as a seamless pipe form, and the welded steel pipe expressed by outer diameter * wall thickness mm, using ordinary carbon steel, high-quality carbon steel or general energy low alloy steel for hot strip, cold strip welding, or hot strip welding Then it is made by cold dialing method. Metric welded pipes are divided into general energy and thin-walled, and are commonly used as structural parts, such as transmission shafts or conveying fluids. Thin-walled pipes are used to produce furniture, lamps, etc., and the strength and bending test of the steel pipe must be ensured.

Roller tube: Electric welded steel pipe for the roller of belt conveyor, generally made of Q215, Q235A, B steel and 20 steel, with a diameter of 63.5-219.0mm. There are certain requirements for the tube bending, end face to be perpendicular to the center line, and ellipticity. Generally, water pressure and flattening tests are carried out.

Transformer tube: It is used to manufacture transformer radiator tubes and other heat exchangers. It is made of ordinary carbon steel and requires flattening, flaring, bending, and hydraulic tests. Steel pipes are delivered in fixed-length or double-length, and there are certain requirements for the bending of the steel pipe.

Special-shaped pipes: square pipes, rectangular pipes, hat-shaped pipes, hollow rubber steel doors and windows welded by ordinary carbon structure steel and 16Mn steel strips, mainly used for agricultural machinery parts, steel windows and doors, etc.

Welded thin-walled pipe: mainly used for making furniture, toys, lamps, etc. In recent years, thin-walled tubes made of stainless steel belts are widely used, such as high-end furniture, decorations, and fences.

Spiral welded pipe: It is made by rolling low-carbon carbon structural steel or low-alloy structural steel strip into a tube blank at a certain spiral angle (called forming angle), and then welding the tube seam together. It can be made with a narrower Strip steel produces large diameter steel pipes. 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 can be welded on one side and on both sides. The welded pipe shall be guaranteed to meet the requirements in terms of hydraulic test, tensile strength and cold bending performance of the weld.