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Knowledge Of Square Tubes

Jan. 16, 2020

Square steel pipe is a hollow strip of steel. It is used as a large amount of pipelines for transporting fluids, such as petroleum, natural gas, water, gas, and steam. In addition, when the bending and torsional strength are the same, Lighter, it is also widely used in manufacturing mechanical parts and engineering structures. It is also often used in the production of various conventional weapons, barrels, and shells. Square steel pipe manufacturer share for you

Classification of square pipes: steel pipes are divided into seamless steel pipes and welded steel pipes (slotted pipes)

Square Steel Pipe

Square Steel Pipe

Product features and uses of square tube:

1. Product description of square tube: Square tube is a kind of hollow square light-section thin-walled steel tube, also known as steel refrigerated curved section. It uses Q235 hot-rolled or cold-rolled strip or coil as the base material, cold-bending and forming, and then high-frequency welding made of square cross-section shape size. In addition to the wall thickness of the hot-rolled extra-thick wall square tube, the corner dimensions and edge flatness have reached or even exceeded the level of cold-formed square tubes for resistance welding.

2. Use of square tubes: construction, machinery manufacturing, steel construction projects, shipbuilding, solar power generation support, steel structure engineering, power engineering, power plants, agricultural and chemical machinery, glass curtain walls, automobile chassis, airports, etc.

5 Overview of welded square pipe

Production method:

① Generally, the temperature of boiler tubes is below 450 ° C. Domestic tubes are mainly made of hot-rolled or cold-drawn tubes of No. 10 and No. 20 carbon steel.

② High-pressure boiler tubes are often in high temperature and high pressure conditions when used. The tubes will oxidize and corrode under the action of high-temperature flue gas and water vapor. Steel pipes are required to have high durability, high resistance to oxidation and corrosion, and good structural stability.

2. Uses:

①General boiler tubes are mainly used to manufacture water-cooled wall tubes, boiling water tubes, superheated steam tubes, superheated steam tubes for locomotive boilers, large and small smoke pipes, and arch brick pipes.

② High-pressure boiler tubes are mainly used to manufacture superheater tubes, reheater tubes, air ducts, and main steam tubes for high-pressure and ultra-high-pressure boilers.

3. Type:

Boiler tube is divided into general boiler tube and high pressure boiler tube according to the high temperature performance. No matter whether it is a general boiler tube or a high-pressure boiler tube, it can be divided into various steel tubes according to different requirements.

4. Specifications and appearance quality:

(1) GB3087-82 "Seamless Steel Pipe for Low and Medium Pressure Boilers". There are 43 kinds of specifications of steel pipes for boilers with various structures, with outer diameters ranging from 10 to 426 mm. A total of 29 kinds of wall thickness 1.5 ~ 26mm. However, the outer diameter and wall thickness of superheated steam pipes, large smoke pipes, small smoke pipes and arch brick pipes for locomotive boilers are otherwise specified.

(2) GB5310-95 "Seamless Steel Tubes for High Pressure Boilers" The outer diameter of the hot-rolled tubes is 22 to 530mm and the wall thickness is 20 to 70mm. The cold-drawn (cold-rolled) tube has an outer diameter of 10 to 108 mm and a wall thickness of 2.0 to 13.0 mm.

(3) The provisions of GB3087-82 "Seamless Steel Pipe for Low and Medium Pressure Boilers" and GB5310-95 "Seamless Steel Pipe for High Pressure Boilers". Appearance quality: No cracks, folds, creases, scars, delaminations or hairlines are allowed on the inner and outer surfaces of the steel pipe. These defects should be completely removed. Depth Q345B I-beam depth [1] shall not exceed the negative deviation of the nominal wall thickness, and the actual wall thickness at the clearing place shall not be less than the minimum allowable wall thickness.