The cutting surface of the square tube shall be true circle, and the cutting line shall be at right angles to the axis of the square tube. Excessive force is the reason for cutting the square tube into flat or oval, so the square tube should be cut with appropriate force.
Cutting: 1 to be fast, no teeth, or whether the cutting line is flat, so when you cut it's easy to leave the corner of the side end.
Satoraljaujhely.Square pipe is the name of square pipe, that is, steel pipe with equal side length. It is made of rolled strip steel after process treatment.
Q355b square pipe for mining fluid transportation, Standard No.: gbt14291-2000. The representative material is Q235 grade B steel, which is mainly used for coal mine air pressure, drainage and vertical shaft gas drainage straight seam q355b square pipe.
.Square tube is in our reality
Square tube failure. When the pipeline is erected, it is necessary to do a good job or directly use the square pipe. The reason for the corrosion of the pipeline is that the layer of the pipeline is damaged. Once the layer is separated from the pipe surface, it will naturally cause failure.
It is a kind of cleaning for the surface of square pipe. Shot blasting is often used to clean the casting surface or strengthen the surface of square pipe.
When the square tube is processed, it needs to be properly polished to ensure durability, smoothness and. There are kinds of polishing for general stainless steel profiles, including mechanical polishing, chemical polishing and electrochemical polishing.
Hardness Q235B square hardness is a pointer to measure the hardness and softness of metal materials. At present, the hardness method is commonly used to measure the hardness in production. It uses the indenter with fixed geometry to measure the hardness value of the metal material surface tested under fixed load according to the degree of hardness.
In fact, the casting cleaning is not just shot blasting. For large parts, the drum sand cleaning is carried out first, that is, the riser of the casting is cut off and rolled in the drum, and the square tubes collide with each other in the drum to remove most of the sand on the surface before shot blasting or shot blasting.
Test conclusion.Function index analysis of square tube - strength and plasticity discussed later are machine function indicators of metal under static load. In practice, the whole opportunity is tired.
When cutting the sample, the surface of the sample shall not be damaged, the properties of the metal shall not be changed due to heating or cold processing, and the edges at the section shall be rounded.
At present, researchers at home and abroad have carried out experimental discussion on the anti adhesion of square tube surface. So far there is still a lack of research on surface adhesion, there is no systematic and perfect theory to guide the preparation of anti adhesion inner surface of pipeline, and there is a lack of operable and low-cost inner surface preparation technology of square pipe. In terms of solid surface adhesion mechanism, based on the solid-liquid interface adhesion work theory and smooth solid surface model, this paper analyzes the spreading process on machined rough surface, studies the dynamic movement characteristics of solid-liquid vapor phase line, directly analyzes the adhesion process, and establishes a line spreading model based on small system energy, It provides theoretical guidance for the preparation of anti adhesion surface of pipeline.
Material classification: square pipe is divided into ordinary carbon steel square pipe and low alloy square pipe.
Test conclusion.The standard number of spiral square pipe (standard of the Ministry of petroleum) for low pressure transmission is syt5037-2008. The representative materials are q235bq345b and other carbon steel materials. It is mainly used for low-pressure transmission of water, natural gas, heating and other pipelines.
The pipeline is only subject to chemical pickling, which can remove oxide scale, rust and old coating. Sometimes it can be used as the reprocessing after sand blasting. Although chemical cleaning can make the surface reach a certain cleanliness and roughness, its anchor lines are shallow and easy to pollute the surrounding environment. The square tube shall be submitted for acceptance in batches, and the batch rules shall comply with the provisions of corresponding product standards.
The purpose of heat is to prevent the generation of cold cracks. Cold crack is directly related to carbon equivalent. Therefore, it is necessary to distinguish the carbon equivalent of the q355b square tube, and the carbon equivalent of the q355b square tube is the same. If the carbon equivalent of Q345 is less than 0.3%, it can be said that the weldability is OK. Generally speaking, the cold crack increases when the carbon equivalent is 0.4%.
Satoraljaujhely.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.
Chemical polishing: less investment in processing equipment, high speed, high efficiency and good durability. Its defects are poor brightness gas overflow, demand for ventilation equipment and difficult heating. It is suitable for processing small batch of disordered parts and products with low brightness demand for small parts.
Mechanical property is an important index to ensure the end use performance (mechanical property) of square pipe, which depends on the chemical composition and heat treatment of steel. In the steel pipe standard, according to different service requirements, yield strength or yield point, elongation), hardness and toughness indexes, as well as the high and low temperature properties required by users are specified.