According to the welding method, it can be divided into arc welded pipes, high -frequency or low -frequency resistance welded pipes, gas welding pipes, furnace welding pipes, and Bondi pipes.
Welding steel pipe: used for oil diamond and machinery and mechanical manufacturing.
Furnace welded pipe: It can be used as a water gas pipe, etc., large -caliber straight seam welded pipes are used for high -pressure oil and gas conveying, etc.; Spiral welded pipes are used for oil and gas transportation, pipe piles, and bridge pier.
Classification according to the shape of the weld can be divided into straight welded pipes and spiral welded pipes
Strailed welded pipes: simple production process, high production efficiency, low cost, and rapid development.
Spiral tube: The intensity is generally higher than that of the straight seam welding pipe. It can use a welded pipe with a large diameter of the narrow gray material. It can also use different welded pipes with different billet production pipe diameters.However, compared with the same length of the same length, the length of the weld is increased by 30 ~ 100%, and the production speed is lower.Therefore, most of the smaller -caliber welded pipes are welded with straight seams, and most of the large -caliber welded pipes are mostly spiral welded.
Spiral seam welding steel pipes are divided into two types: automatic arc welded steel pipe and high -frequency welding steel pipe.
a. The automatic arc welded steel pipe of the spiral seam is divided into two types: Class A and Class B.Class A pipes are generally welded with general carbon steel Q235, Q235F and general low alloy structure steel 16MN. Class B tube uses steel such as Q235, Q235F, Q195, and is used as a low -pressure fluid conveyor tube.
b. The spiral seam high -frequency welding steel pipe spiral seam high -frequency welding steel pipe has no uniform product standards. Generally, ordinary carbon steel Q235 and Q235F are made of steel.
It is divided into general welded pipes, galvanized welded pipes, oxygen -blowing tubes, electric wire sleeves, public welded pipes, roller tubes, deep well pump pipes, automotive pipes, transformer pipes, welding thin wall pipes, welding alien pipes and spiral pipes.
General welded pipes: General welded pipes are used to transport low -pressure flow.Made with Q195A, Q215A, Q235A steel.It can also be made of other soft steels that are easy to weld.Steel pipes should conduct experiments such as water pressure, bending, and flattening, and have certain requirements for the surface quality. Usually the delivery length is 4-10m, and the fixed ruler (or multiple ruler) is often required.The specifications of the welded pipe are expressed in the nominal caliber (millimeter or inch). The nominal caliber is different from the actual. The welded pipe has two types: ordinary steel pipes and thick steel pipes according to the regulations. The steel pipe is divided into two types: threaded and without thread according to the prescribed wall.
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 galvanized and electroplating. The hot -dip galvanized galvanized layer is thick and the cost of electroprilizer is low.
Oxygen-blowing pipe: For steelmaking oxygen blowing pipes, generally use small-caliber welding steel pipes. The specifications are eight from 3/8 inch-2 inches.Made with 08, 10, 15, 20 or Q195-Q235 steel bands.In order to prevent corrosion, some permeation of aluminum treatment is performed.
Circuit sleeve: It is also an ordinary carbon steel steel tube, which is used in concrete and various structural power distribution projects. The commonly used nominal diameter is 13-76mm.The tube wall of the wires is thinner, and most of them are used after coating or galvanized. The cold bending test is required.
Public welded pipe: The specifications are used in the form of seamless pipes, welded steel pipes represented by the outer diameter*wall thickness millimeter, tropical, cold band welding of ordinary carbon steel, high -quality carbon steel or general energy low -alloy steel, or after tropical welding with tropical weldingIt is made by the cold dial method.Public welded pipes are divided into universal energy and thin walls, ordinary use as structural parts, such as transmission shafts, or conveying fluids, and thin walls to produce furniture, lamps, etc., to ensure the strength and bending test of the steel pipe.
Rolling tube: It is used for welding steel pipes of the roller roller, which is 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 and end of the tube, the end surface, and the ellipse degree of the center line. Generally, the hydraulic and compression test is performed.
Transformer tube: It is used to make a transformer cooling pipe and other heat exchangers. It is made of ordinary carbon steel and requires flattening, expansion, bending, and hydraulic testing.Steel pipes are delivered with a fixed ruler or multiple meter, which has certain requirements for the curvature of the steel pipe.
Different pipes: square tubes, rectangular tubes, hat -shaped pipes, air -gum steel doors and windows for welding of steel bands such as ordinary carbon structures and 16MN are mainly used as agricultural institutions, steel window doors, etc.
Welding thin wall tube: mainly used to make furniture, toys, lamps, etc.The thin -wall tube made of stainless steel belt is widely used, high -end furniture, decoration, fence, etc.
Spiral welded pipe: It is to roll the low -carbon carbon structure steel or low -alloy structure steel band according to a certain spiral line (called molding angle) into a pipe blank, and then welded the pipe seam.Bring steel to produce large diameter steel pipes.The spiral tube is mainly used for the transportation pipeline of oil and natural gas. The specifications are represented by the outer diameter*wall thickness.If the spiral pipe has a single -sided welding and double -sided welding, the welded pipe should ensure the hydraulic test, the tensile strength of the weld, and the cold bending performance.
