In the process of square pipe, we will continue to innovate. Let's introduce the main elements contained in the lower pipe. For the martensitic chromium square tube, the main elements affecting the are chromium, carbon and molybdenum; For Martensitic chromium nickel square tube, molybdenum, aluminum, cobalt, nitrogen and titanium.
The square tube is a low-alloy high-strength structural steel with carbon content of 0.1% - 0.25%, and the main alloy elements manganese, silicon, vanadium, niobium and titanium are added; Its total alloy content is 3%. According to the strength, it is divided into four levels: 300, 350, 400 and 450MPa.
Tulzia cimpia turzii.When sand blasting or manual mechanical derusting is used, due to the falling off of the oxide scale of the galvanized square pipe, the metal on the surface of the galvanized square pipe is directly exposed in the air. If a primer is not applied in time, the surface of the galvanized square pipe is easy to rust again, affecting the adhesion of the paint film. I am engaged in all kinds of square tubes, square rectangular tubes, seamless square tubes, galvanized square tubes, galvanized tubes and other materials all year round. I operate in good faith. Welcome to call! As the paint is a time-effective material, the overstock of inventory is easy to expire. Therefore, the main indexes of the paint must be rechecked before use, and the paint can be used only when the results meet the standards.
The q355b square tube rolled from the strip steel through process treatment is generally to unpack, flatten, curl and weld the strip steel to form a round tube, then roll the round tube into a square tube, and then cut it to the required length. Nowadays, the forming of q355b square tube has solid bending and empty bending. The bending degree of q355b square tube shall not be greater than 3mm per meter, and the total bending degree shall not be greater than the actual bending of the total length. As the name suggests, the bending is compacted, and the internal and external rollers and the internal and external walls of the tube blank are compacted in both directions during the actual bending.
.In terms of hot working, repeated upsetting and multi-directional rolling of ingot can not only reduce the level of carbide segregation in square tube, but also improve the anisotropy of steel.
Ordinary carbon steel is divided into Q19 Q2 q23 SS400 20# steel, 45# steel, etc.
Process flow of square tube drawing: because the size of the die hole of the square tube drawing is smaller than the outer diameter of the tube in front of the drawing, in order to make the front end of the square tube pass through the die hole smoothly, so that the clamp jaw of the drawing trolley can the head of the square tube, it is necessary to sharpen the head of the square tube before drawing. Therefore, the end of the square tube with a fixed length should be heated in the slit heating furnace, and the heating temperature is between 750 ~ 900 ℃ according to different wall thickness. Then use 75 ~ 300kg air hammer to sharpen and grind the head of the square pipe. Generally, the square pipe with diameter less than 22mm can be sharpened by rotary forging hammer or roll forging machine.
The common surface treatment of square pipe includes surface treatment chemical treatment, shot blasting treatment, manual mechanical treatment and flame treatment. The treated will be separated. 4 ~ 6Mpa compressed air entrains abrasives, and the nozzle sprays to the steel surface at high speed. The impact and friction of abrasives remove the oxide scale, rust and dirt on the steel surface, and make the steel surface reach a certain roughness.
Change to square pipe: generally, the strip steel is unpacked, leveled, crimped and welded to form a round pipe, then rolled into a square pipe from the round pipe, and then cut into the required length. Stage (1904 & mdash; 1934)
The function index analysis of the square tube - the strength acts with great progress. The load on the parts is called the charge and trap load. The damage power of the square tube under the charge and trap load is called the charge and trap toughness.
Professional is king.Avoid contact with pollutants such as oil and copper when storing square tubes.
In order to ensure excellent coating quality, the coating is required to be firmly attached to the surface of the coated object. This depends on the quality of the coating itself; On the other hand, it depends on the quality of the coated surface treatment before construction. After various surface treatments, the coating quality and economic effect are very different.
Avoid contact with pollutants such as oil and copper when storing square tubes.
High hardness square tubes mainly bear fatigue load, so they must have high hardness. Therefore, quenching,Tulzia cimpia turziiConnection mode of galvanized square pipe, surface quenching or chemical heat treatment shall be carried out, followed by low-temperature tempering treatment.
ranking.Classification of surface treatment square pipe is divided into hot-dip galvanized square pipe, electro galvanized square pipe, oiled square pipe and pickled square pipe according to surface treatment.
Steel used & mdash& mdash; Such as bridge steel ship steel, boiler steel,Tulzia cimpia turziiProduction video of galvanized square pipe, pressure vessel steel agricultural machinery steel, etc.
According to the welding specification, process test and process analysis,Tulzia cimpia turzii65 galvanized pipe, it is determined that the butt weld of Q345B square pipe adopts double-layer CO2 gas shielded welding. H08Mn2SiA, 2mm welding wire for welding material; The shielding gas is pure CO2 gas. The welding current of layer weld is 200 ~ 250A, and that of the second layer is 240 ~ 320A; The arc voltage is 24 ~ 26V. The process requirement is that the layer weld must be fully welded to ensure good back forming; The welding current, wire feeding speed and welding speed can be adjusted according to the equipment model.
Tulzia cimpia turzii.Surface adhesion resistance is an important feature of square tubes. At present, square tubes are mostly used for transportation, so the adhesion resistance makes square tubes not stick during transportation.
The test can be carried out under cold and hot conditions. If the test temperature is not specified, the test shall be carried out under normal temperature, but not lower than - 10 ℃.
The square tube represents the large capacity of the metal material under the action of tension and the calculation formula is: where: FB -- the strong force borne by the sample when it is broken, mm2. Yield point (& sigma; s) the stress of metal material with yield phenomenon when the specimen can continue to elongate without increasing (keeping constant) the force during the tensile process, which is called the yield point.