Stage ( & mdash; )Square tube is an essential material for the construction and Realization of industrialization. It is widely used and has a wide variety. According to different section shapes, square tube is generally divided into sections,Kingston1-inch galvanized steel pipe for greenhouse, plates, pipes and metal products. In order to facilitate the production, ordering and supply of square tube and do a good job in operation and management, it is also divided into heavy rail, light rail, large section steel, medium section steel, small section steel and square tube cold bending Section steel, high-quality section steel, wire rod, medium and thick steel plate, sheet steel, electrical silicon steel sheet, strip steel, seamless steel pipe, square pipe,KingstonHot dip galvanized steel pipe for inner and outer wall, welded steel pipe, metal products, etc.Kingston,Mechanical polishing: after processing the parts have good levelness, short gloss, dull and rusty. Suitable for processing simple parts medium and small products.Hot dip galvanized square pipe is widely used, mainly in curtain wall, construction, machinery and steel structure engineering, especially in curtain wall, machinery and construction. The effect of cold galvanized square tube is far from that of hot galvanized square tube; How to distinguish hot galvanized square pipe from cold galvanized square pipe?Hastings, many machine parts work under cyclic load plasticity and hardness discussed above are indicators of the mechanical properties of metals under static load. In fact, under which fatigue will occur.Viewing color: the color of the cold galvanized square tube is yellowish green, cyan white or slightly colored at a fixed angle with the sun. The color of hot-dip galvanized square pipe is silver white at a fixed angle with the sun.Derusting grade for the construction process of epoxy, ethylene phenolic and other coatings commonly used for square pipes, the surface of square pipes is generally required to reach near white grade (SA). Practice has proved that almost all oxide scale, rust and other dirt can be removed by using this derusting grade, and the depth of anchor grain can reach ~ & mu; m, which fully meets the requirements of adhesion between layer and square pipe The shot derusting process can meet the technical conditions of near white level (SA) with low operation cost and stable and reliable quality.

Among them, qb square tube is divided into: (a) by process & mdash& mdash; Arc welded square pipe, resistance welded square pipe (high frequency and low frequency), gas welded square pipe and furnace welded square pipe (b) are divided by weld & mdash& mdash; Straight seam welded square pipe, spiral weldingWhen we understand the causes of defects in the drawing process of qb square tube, we should constantly improve the technology in the subsequent production process, so that we can reduce the occurrence of defects.Improve the positioning and pre bending steps, if necessary, to ensure that the web hunting problem does not occur when pressing parts. Change the shape of the surface pressure of the material to ensure the quality of the parts and avoid the non movement of the surface shape of the roll gap, resulting in uneven walking feeding.Administration,C. special performance steel: (a) stainless and acid resistant steel; (b) Heat resistant steel; (c) Electric heating alloy steel; (d) Electrical steel; (e) High manganese wear resistant steel.Large diameter qb square tube production standard classification square tube is divided according to production standard: national standard square tube, Japanese standard square tube, British standard square tube, American standard square tube, European standard square tube and non-standard square tube.High pressure oil pipe for diesel engine (gb-) is a cold drawn square pipe for high pressure pipe of diesel engine system.

Square tube, QB square tube and hot-rolled square tube are qualified in quality inspection. The manufacturer adopts advanced equipment to ensure the quality of each product. Magnetic flux leakage testing for surface defects of square tubes is very similar to magnetic particle testing for square tubes, and its scope of application, sensitivity and reliability are stronger than magnetic particle testing. Indirect square forming process the traditional forming process of cold-formed square pipe is to gradually roll the hot-rolled steel coil multi stand forming unit into round pipe at room temperature, and then the shaping unit will roll the round pipe into square pipe, which is called indirect square forming process. The traditional roll forming process uses the method of fixed bending point position and variable bending radian to complete the corner forming of pipe blank, which is suitable for rolling small and medium-sized products. Rolling with this process & ldquo; Superb & rdquo; Square tube will show its inherent defects. Because the roll work in the bending process of this process is always concentrated at the point, excessive stress concentration often shows microcracks in the bending process of profiles, which will lead to cracking in serious cases. The products with such defects have serious consequences when they are used in building steel structures. The study of the broken square tube column in the Hanshin earthquake in Japan shows that the corner microcrack is the main cause of the square tube fracture. At the same time, due to the different forming bending radians of products with different wall thickness, the universality of rolls is limited. The large-size cold-formed square tube used in the process adopts the advanced & ldquo; Direct Square & rdquo; The production process is to directly roll the hot-rolled steel coil into a square and rectangular shape at room temperature.The cheapest,Special performance steel: A. stainless and acid resistant steel; b. Heat resistant steel: including oxidation resistant steel, heat strength steel and air valve steel; c. Electric heating alloy steel; d. Wear resistant steel; e. Low temperature steel; f. Electrical steel.Functional index analysis of square tube - commonly used are square tube Brinell angle (HB), Rockwell angle (HRC) and Vickers angle (HV). Angle is a gauge needle to weigh the soft and hard level of metal data. The angle method is rarely used to determine the internal angle in the current life. It uses the metal data surface tested under the fixed load of the indenter with a certain number and shape to determine its angle value according to the level of the object.Square tubes are classified by forming: forged steel; Cast steel; Hot rolled steel; Cold drawn steel.Kingston,According to smelting classification and furnace type, A. open hearth steel: (a) acid open hearth steel; (b) Alkaline open hearth steel.Carbon steel classified by chemical composition: square tube A. low carbon steel (C & le; .%); b. Medium carbon steel (C & le; . ~ .%); c. High carbon steel (C & le; .%).The square tube for fluid transportation (gbt-) is a general square tube for transporting water, oil, gas and other fluids.