If the test results of square tubes fail to meet the provisions of product standards, the unqualified ones shall be selected, and double the number of samples shall be taken from the same batch of square tubes for re inspection of unqualified items. If the re inspection results (including any index required by the test of the project) are unqualified, the batch of square tubes shall not be delivered. If the following inspection items fail to pass the preliminary inspection, re inspection is not allowed: A. There are white spots in the low magnification; b. Microscopic.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 ( & mdash; )GuanajieSquare tubes are low alloyPurpose of square tube the purpose of square tube includes construction, machinery, steel construction and other projects, shipbuilding, solar power generation support, steel structure engineering, electric products ( pieces)Sefrou,It is the process of drawing the die hole of the rolled metal blank (shape, product, etc.) into a section to reduce the length and increase. It is mostly used for cold processing.Comprehensive classification ordinary steel A. carbon structural steel: (a) Q (b) Q (b); (c) Q( C)； (d) Q( B)； (e) Q.Forging square tube: a kind of pressure processing in which the reciprocating impact force of the forging hammer or the pressure of the press changes the blank into the shape and size we need. It is generally divided into forging and die forging. It is often used to produce large-scale materials and materials with large square tube size.

With the progress of the times and the faster and faster economic development, the application of color qb square tube treatment technology includes chemical method and electrochemical method from the process point of view. They can get different colors by treatment in specific electrolyte, so as to improve the wear resistance, color and variety of qb square tube, which can be applied to different occasions and obtain different economic benefits.Fatigue strength, many machine parts work under cyclic load, under which fatigue will occur.Excellent service,Because the green billet can be pressed into any shape, it is easy to weld the square tube into difficult products.For improper stamping direction, simulation software shall be used in the initial stage of design to ensure that the direction of stamping parts is analyzed, and when the high-quality requirements of components require the re development of molds, the direction shall be adjusted to seamless square tubes. The square tube manufacturer introduces the forming, bending and bending of square tubes. As the name suggests, the bending is compacted and the inner and outer rollers are double with the inner and outer walls of tube billets during actual bending Compact towards the.Put the pig iron for steelmaking into the steelmaking furnace according to the specified process to obtain steel. The products of steel include ingots, continuous casting billets and various steel castings made of straight square tubes. Generally speaking, steel refers to the steel rolled into various square tubes. Square tube steel belongs to ferrous metal, but steel is not completely equal to ferrous metal.

Section shape classification of large-diameter qb square tube square tube is classified according to section shape: simple section square tube & mdash& mdash; Square tube, rectangular tube and complex section square tube & mdash& mdash; Flower shaped square pipe, open square pipe corrugated square pipe, special-shaped square pipe, large-diameter qb square pipe surface treatment classification square pipe is divided according to surface treatment: hot-dip galvanized square pipe, electro galvanized square pipe, oil coated square pipe, acid pickling square pipe, large-diameter qb square pipe purpose classification square pipe is classified according to purpose & mdash& mdash; Square tubes for decoration, machine tool equipment, machinery industry, chemical industry steel structure, shipbuilding, automobile, steel beam and column, special purpose, large-diameter qb square tube wall thickness classification large-diameter qb square tube according to wall thickness Classification & mdash& mdash; Super large diameter qb square pipe, large diameter qb square pipe and thin-wall large diameter qb square pipe rectangular pipe are the names of square pipe and QB square pipe, that is, steel pipe with equal side length. It is made of rolled strip steel after process treatment. Generally,GuanajieDimensions of galvanized square pipe, the strip steel is unpacked, 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. Usually pieces per bag. Qb square pipe, also known as square and rectangular cold-formed hollow section steel, is referred to as square pipe and rectangular pipe, code f and j respectively. The allowable deviation of wall thickness of qb square pipe shall not exceed plus or minus % of nominal wall thickness when the wall thickness is not greater than mm, plus or minus % of wall thickness when the wall thickness is greater than mm, except for the wall thickness of corner and welding joint area.Potential development,Hardness QB 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.The strength, plasticity and angle discussed later are the machine function indicators of metal under static load. In practice, many mechanical machines are under repeated load, and the whole opportunity is tired in this environment.Change to square pipe: generally, the strip steel is unpacked, 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 ( & mdash; )Guanajie,Spraying (throwing) derusting spraying (throwing) derusting is that the high-power motor drives the spraying (throwing) blade to rotate at high speed, so that the steel sand, steel shot, iron wire section, minerals and other abrasives can be sprayed (thrown) on the surface of the square tube under the action of centrifugal force, which can not only completely remove rust, oxides and dirt, but also the square tube under the violent impact and force of abrasives, It can also achieve the required uniform roughness.There are many ways of ignition, such as arc, electric spark, flame, strong current, high-temperature furnace, electron beam, laser, high-temperature radiation, microwave, chemical furnace, etc.When storing QB square pipe, we need to select a suitable place. We need to think about many external factors, such as the corrosivity of steel pipe, etc. Therefore, the place must be clean, dry and ventilated, where harmful gases appear, QB square pipe can not appear weeds and other sundries should be removed in time, and the outer surface of steel should be kept clean. If there are acid, alkali, salt, etc. in the warehouse, it is easy to react with the steel pipe and corrode the steel pipe, so try to cut it and don't let it. In addition, if we can think about those higher metal products, there is a sealed warehouse, but the ventilation setting is excellent. The difference between QB square tube and seamless steel tube QB square tube is a kind of high-precision steel tube material after cold drawing or hot rolling treatment. QB square tube is mainly used to produce products of pneumatic or hydraulic components, such as air cylinder or oil cylinder, which can be seamless pipe or welded pipe, because there is no oxide layer on the inner and outer walls of QB square tube, no deformation under high pressure, high precision, high finish, flaring and flattening without cracks. The chemical composition of QB square tube includes carbon silicon Si, manganese Mn, sulfur s phosphorus P and chromium CR.