Stainless steel q355b square pipe for fluid transportation, Standard No.: gbt12771-1991. The representative materials are 0Cr 0cr19ni 00cr19ni 00cr1 0cr18ni11nb, 0017cr17ni14mo2, etc., which are mainly used to transport low-pressure corrosive media.
Galvanized q355b square pipe for low pressure fluid transmission, gas, air, oil and heating hot water or steam. The surface of square pipe adopts hot galvanizing or cold galvanizing process.
Orange-Walk.At this time, if the welding wire of the same material is used for spot welding where the thickness is insufficient, it shall be welded to the fixed thickness, ground and sandblasted, and repair welding shall be adopted where there are cracks, even if the steel pipe with another large opening can be made up at one time.
Square tube flattening test is a kind of test to check the deformation performance of metal tubes (seamless square tubes and rectangular tubes) flattened to the specified size and show their defects. Relevant flattening tests shall be carried out in accordance with relevant provisions of test standards. Requirements for samples samples can be taken from metal pipes with qualified appearance. Generally, sawing is adopted. The inner and outer walls of the pipe shall retain the original surface without any processing. Sample length L & asymp; D (D is the outer diameter of the pipe). When the outer diameter is large, the length l shall not exceed 100mm. When the outer diameter is less than 20mm, l = 20mm. When cutting the sample, the surface of the sample shall not be damaged and the performance of the metal shall not be changed due to heating or cold processing. The edge of the section shall be flattened. The flattening test is a test to check the deformation performance of the metal pipe (seamless square pipe and rectangular pipe) flattened to the specified size and show its defects. Relevant flattening tests shall be carried out in accordance with relevant provisions of test standards.
.Square tube is made of steel ingot or solid tube blank through perforation, and then made by hot rolling, cold rolling or cold drawing. Square pipe plays an important role in steel pipe industry.
Brinell hardness, Rockwell hardness and Vickers hardness are commonly used.
The butt joint between the head and tail of square pipe and strip steel adopts single wire or double wire submerged arc welding, and automatic submerged arc welding is adopted for repair welding after rolling into square pipe.
General square pipes are stacked outdoors, and most of them are buried underground when in use, so they are easy to corrode and rust. In order to ensure the smooth flow of the pipeline, square pipes must have strong corrosion resistance. Once the pipeline is corroded, it will cause oil and gas leakage which will not only interrupt transportation, but also pollute the environment and may even lead to fire and cause harm.
Square tube production most square tube processing is square tube pressure processing, resulting in plastic deformation of the processed steel (billet, ingot, etc.). According to the square tube processing temperature, the square tube can be divided into cold processing and hot processing. The main processing of square tube includes: rolling: the gap (various shapes) between the square tube metal blank and the rotating roll , because of the compression of the roll, the material section is reduced and the length is increased. This is a common production method for producing square tubes. It is mainly used to produce square tube profiles, plates and tubes. It is divided into cold rolling and hot rolling.
Square tubes are more and more widely used in practice. Different types of square tubes have different characteristics, and the performance of each type of square tube is also different. Choose according to its performance in different aspects, so as to improve its work efficiency. Next, let's introduce what should be paid attention to when heating the lower tube.
Highly recommended.Low alloy steel is divided into q34 16Mn, Q390, St52-3 etc.
The selected punch and die fillets are related to the magnitude and distribution of stress
The square tube is formed by external control or internal control roller.
Application: it is widely used in machinery, construction, metallurgy,Orange-WalkHot dip galvanized steel pipe, agricultural vehicles, agricultural greenhouses, automobiles, railways, highway guardrails, container frames, square tubes, welding wires and fluxes. It must undergo strict physical and chemical inspection before being put into operation.
Credit guarantee.Dimensional stability for high-precision square tubes, the required accuracy is high, so the dimensional stability must be maintained. Due to straightening in the air and slow cooling speed, it has the effect of stabilization and will increase the number of residual square tubes in the,Orange-WalkCold galvanized square pipe factory, so it must be cooled; Reduce quenching deformation because the square tube is slender, it is easy to deform during quenching, so its deformation must be strictly controlled. Heat treatment is a key process. In the process of quenching and cooling, the cold plasticity shall be corrected in time, which is a key step to ensure the improvement of its qualification rate. Therefore, hot bath quenching or cooling in oil for a fixed time shall be carried out to propose thermal correction.
Hot dip galvanized square pipe is widely used, mainly in curtain wall, solar power generation support, construction, machinery and steel structure engineering, especially in curtain wall, we should constantly improve the technology in the subsequent production process, so that we can reduce the occurrence of defects.
Orange-Walk.Large diameter welded square pipe for low pressure fluid transmission, Standard No.: gbt14980-1994. Representative material: q235ab grade. It is mainly used to transport low-pressure fluids, such as water, sewage, gas, air and heating steam.
The calculation method theory of square tube mechanics is feasible to calculate static structures, houses and bridges,Orange-Walk25mm galvanized square pipe, but it is not suitable for moving components such as wheels. At this time, people often use the plastic theory. The research of the plastic theory can be traced back to 1914. In 1975 the European Design Association formulated D plastic design code, which is mainly used for plane beams under static load and bending stress For the frame structure with stress the requirements are as follows:% 26sigma; B% 26sigma;% 26zeta;% 26ge;% 26delta;% 26ge; 15% for high-rise buildings, more detailed calculation is required. In the case of plastic design, the allowable stress is usually calculated according to the safety factor that the allowable stress is not less than the dynamic load and multiplied by the allowable stress. In the case of bending of an axis, the formula a = w can be used Using plasticity instead of calculated strength can improve the bearing capacity of members by 14%.
Stainless steel q355b square pipe for mechanical structure, Standard No.: gbt12770-1991. Representative material 0Cr 1cr1 00cr19ni 1Cr18Ni 0cr18ni11nb, etc. It is mainly used for machinery, automobile, bicycle, furniture, hotel and restaurant decoration and other mechanical parts and structural parts.