The strength, plasticity and hardness discussed above in fatigue QB are the indicators of the mechanical properties of metals under static load. In fact, many machine parts work under cyclic load, under which fatigue will occur.Square tube, modified square tube, 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 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.St. Louis , and this defect often runs through the longitudinal direction of the whole product. The reason for the folding is that the fake and shoddy manufacturers pursue the rate, the reduction is too large, resulting in ears, folding occurs during the next rolling, the folded products will crack after bending, and the strength of the square tube will be greatly reduced.Safita,Ferroalloy is an alloy composed of iron and silicon, manganese, chromium, titanium and other elements. Ferroalloy is the raw material for steelmaking. It is used as deoxidizer and alloy element additive for steel in square tube steelmaking.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, 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, etc.Functional index analysis of qb square tube - the load on the machine parts due to the great progress of strength is called the frontal collapse load. The power of destruction of qb square tube under the frontal collapse load is called the frontal collapse toughness.

The second is to clean the surface of the opposite pipe. When cleaning the opposite pipe metal products, the surface should be cleaned with solvent or emulsion. Square pipes of various specifications,St. Louis Galvanized hot dip galvanized pipe, square rectangular pipes, seamless square pipes, galvanized square pipes, which can not remove rust and oxide scale. Therefore, it can only be used as an auxiliary means in production.The new improvement ensures that square tubes can be used for a long time. With the development of the times, square tubes are used in more and more fields. So how can we correctly choose square tubes? Next, I'll introduce the process of lower tubes.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,St. Louis 3x4 square tube,St. Louis Price of galvanized square pipe DN100, 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.Development Curriculum,Zinc layer thickness: there is a great difference between cold galvanized square pipe and hot galvanized square pipe in galvanizing process; Cold galvanized square pipes are prone to & ldquo; Electric burning & rdquo; The color of this part is gray and the zinc layer is thick. It is easy to form a current dead angle at the corner, resulting in an under current area. The zinc layer at this part is thin, and there is no zinc layer attached to the cold galvanized square pipe. The cold galvanized square pipe has no zinc lump and caking as a whole but the overall zinc layer is thin, and the thickness of the outer wall zinc layer is μ m-μ m. The and outer walls of the hot-dip galvanized square tube are attached with zinc layer, and there will be water marks and a few zinc tumors, but the overall zinc layer is thick, and the thickness of the zinc layer on the inner and outer walls of the square tube is -mu; M above. The nature of QB square tube!High density may not be obtained by simple pressurization, and insulation shall be carried out at the same time.Fatigue strength, plasticity and hardness discussed above are indicators of the mechanical properties of metals under static load. In fact, many machine parts work under cyclic load, under which fatigue will occur.

The square tube for fluid transportation (gbt-) is a general square tube for transporting water, oil, gas and other fluids.Administration,Tool derusting mainly uses tools such as steel wire brush to polish the surface of square pipe, which can remove loose or oxidized scale, rust, welding slag, etc. The derusting of manual tools can reach grade SA and that of power tools can reach grade SA. If the square pipe surface is firmly attached with iron oxide scale, the derusting effect of tools is not ideal and can not reach the anchor depth required by construction.The standard number of spiral square pipe (standard of the Ministry of petroleum) for low pressure transmission is syt-. The representative materials are qbqb and other carbon steel materials. It is mainly used for low-pressure transmission of water, oil, natural gas, heating and other pipelines.It should be noted that the position of the disc from the calibration line can be adjusted according to the reinforcement diameter, and R and R can be equal or different.St. Louis The appearance of fake and inferior square tubes often has pitting. Pockmarked surface is an irregular uneven defect on the surface of square lead pipe due to serious wear of rolling groove. Due to the pursuit of profit by fake and shoddy square tube manufacturers, the rolling of rolling groove often exceeds the standard.Because the green billet can be pressed into any shape, it is easy to weld the square tube into difficult products.Zinc layer thickness: there is a great difference between cold galvanized square pipe and hot galvanized square pipe in galvanizing process; Cold galvanized square pipes are prone to & ldquo; Electric burning & rdquo; The color of this part is gray and the zinc layer is thick. It is easy to form a current dead angle at the corner, but the overall zinc layer is thin, and the thickness of the outer wall zinc layer is μ m-μ m. The and outer walls of the hot-dip galvanized square tube are attached with zinc layer, and there will be water marks and a few zinc tumors, but the overall zinc layer is thick, and the thickness of the zinc layer on the inner and outer walls of the square tube is -mu; M above. The nature of QB square tube!