Square tube is a hollow square section light-weight thin-walled steel tube, also known as steel refrigeration bending profiles. It is made of Q235 hot-rolled or cold-rolled strip or coil as base material by cold bending, forming and high frequency welding. Except for wall thickness increasing, the corner dimension and edge flatness of hot-rolled square tube with extra-thick wall reach or even exceed the level of resistance welding cold-formed square tube. It has good mechanical properties, weldability, cold, hot working and corrosion resistance, and good low temperature toughness.
Performance of square tube
1. Plasticity refers to the ability of metal materials to produce plastic deformation (permanent deformation) without destroying under load.
2. Hardness and hardness are the indicators to measure the degree of hardness and softness of metal materials. Pressure hardness method is the most commonly used method to measure hardness in production at present. It uses a certain geometric shape of the pressure head to press into the tested metal material surface under a certain load, and to measure its hardness value according to the degree of pressure.
Common methods include Brinell hardness (HB), Rockwell hardness (HRA, HRB, HRC) and Vickers hardness (HV).
3. The strength, plasticity and hardness discussed before fatigue are all mechanical performance indicators of metals under static loads. In fact, many machine parts work under cyclic loads, under which fatigue occurs.
4. The load that impact toughness acts on the parts at a great speed is called impact load, and the ability of metal to resist damage under impact load is called impact toughness.
5. Strength strength refers to the resistance of metal materials to failure (excessive plastic deformation or fracture) under static load. Because the load acts in the form of tension, compression, bending and shearing, the strength can also be divided into tensile strength, compressive strength, flexural strength, shear strength and so on. There is always a certain relationship between various strengths. Tensile strength is usually used as the most basic strength indicator.
Square pipes are used in construction, machinery manufacturing, steel construction and other projects, shipbuilding, solar power bracket, steel structure engineering, power engineering, power plant, agricultural and chemical machinery, glass curtain wall, automobile chassis, airport, boiler construction, high-speed rail, building, pressure vessel, oil storage tank, bridge, power station installation. Equipment, lifting and transportation machinery and other welding structures with higher loads, etc.