Square tube is a hollow square section of light thin-walled steel pipe, also known as steel refrigeration bending profile. It is Q235 hot-rolled or cold-rolled strip or coil for the base material by cold bending process forming and then high-frequency welding made of square cross-sectional shape size of the steel. Hot-rolled extra thick wall square tube in addition to wall thickness thickening outside the case, its corner dimensions and edge straightness are up to or even exceed the level of resistance welding cold forming square tube. Comprehensive mechanical properties are good, weldability, cold and hot processing properties and corrosion resistance are good, with good low temperature toughness.
Performance of square tube
1. Plasticity: plasticity refers to the ability of a metal material to produce plastic deformation (permanent deformation) under load without damage.
2. Hardness: Hardness is a measure of the degree of hardness and softness of metal materials pointer. The most commonly used method for determining hardness in production is the indentation hardness method, which uses a certain geometry of the indenter to press into the surface of the tested metal material under a certain load to determine its hardness value according to the degree of being pressed into it.
Commonly used methods are Brinell hardness (HB), Rockwell hardness (HRA, HRB, HRC) and Vickers hardness (HV) methods.
3. Fatigue: the strength, plasticity and hardness discussed earlier are all mechanical properties of the metal under static load pointer. In fact, many machine parts are working under cyclic load, in this condition parts will produce fatigue.
4. Impact toughness: the load acting on the machine parts at a great speed is called impact load, the ability of the metal to resist damage under impact load is called impact toughness.
5. Strength: Strength is the resistance of metal materials to damage (excessive plastic deformation or fracture) performance under static load. Because of the way the load has tensile, compression, bending, shear and other forms, so the strength is also divided into tensile strength, compressive strength, bending strength, shear strength, etc.. There is often a certain connection between the various strengths, the use of tensile strength is generally more as the most basic strength pointer.
Square tube is used in 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, boiler construction, highway railings, housing construction, pressure vessels, petroleum storage tanks, bridges, power station equipment, lifting and transport machinery and other higher load welded structural parts, etc.
Open at both ends and has a hollow concentric circle section, its length and the perimeter of a larger comparison of steel. Round tube specifications with the outer dimensions (such as outside diameter or side length) and internal diameter and wall thickness, its size range is very wide, from a very small diameter of capillary tube to the diameter of several meters of large round steel pipe.
Round tubes can be used for pipelines, thermal equipment, mechanical industry, petroleum and geological drilling, containers, chemical industry and special purposes.
Commonly used structural round steel used for different purposes according to the size of the specifications, small for decorative elements, assembled roof frame, support elements, mesh and pipe trusses, etc., large can be used for heavy steel plant steel pipe concrete steel columns, large stadium pipe trusses, etc.; another major use of round steel is process piping, but generally have special material and anti-corrosion requirements.