According to metallographic classification, the annealed state of square tube: A. hypoeutectoid steel (ferrite + pearlite); b. Eutectoid steel (pearlite); c. Steel precipitation through a common square tube (pearlite + cementite); d. Ledeburite steel (pearlite + cementite).The floating mandrel mill is in its heydayBohong tribe, 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.When storing QB square pipe, we need to select a suitable place. We need to think about many external factors,Bohong tribeHot dip galvanized steel pipe, 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, and the outer surface of steel should be kept clean. If there are acid, alkali, salt etc. in the warehouse, 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, cold bending, 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.Gardabar,Stage ( & mdash; )Principle of cold drawing strengthening: the lattice defects of steel increase during plastic deformation, and the serious distortion of defect lattice will hinder the progress and slip of lattice, so the yield point of steel increases and the plasticity and toughness decrease. Due to the internal stress in plastic deformation, the modulus of steel decreases. The cold drawn reinforcement is stored at room temperature for ~ d or heated to ~ ℃ and maintained for a fixed time. This process is called aging treatment.High quality steel (P & le; .%, S & le; .%)
Square tubes have different functions and different characteristics. Square tubes of various specifications, square rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes are welcome to waste merchants, industries, enterprises and power departments to visit and negotiate! Oxidation will also occur on the surface of square tubes after long-term use. What should we do if oxidation occurs? Let me give you a detailed introduction on how to remove square tubes Oxide scale.The welded joints of square pipes are subject to on-line continuous ultrasonic automatic flaw detector to ensure the NDT coverage of spiral welds. If there are defects, it will automatically alarm and spray marks. The production will adjust the process parameters at any time to eliminate the defects in time.Generally, chemical and electrolytic methods are usedInterpretation and observation,Derusting: This is an important process for galvanized square pipes and components before coating, and it is the key to the quality of galvanized square pipes. Thorough derusting can improve the adhesion of antirust paint and prolong the service life of galvanized square pipe.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,Bohong tribeGalvanized pipe factory, 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.Solution treatment and nondestructive testing sand rolling treatment and sand blasting treatment many manufacturers in the market do not do solution treatment and % penetration nondestructive testing, and many of them use sand blasting instead of sand rolling. After these steps are omitted, the cost is greatly reduced.
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, It can also achieve the required uniform roughness.Promise and keep promise,The pressurization size and time are the key to the success or failure of welding. If the square tube synthetic material is not pressurized, a large number of pores will be caused due to the pores of the material itself and the gas generated in the reaction. It is not allowed to leave the reactants in the weld, so it must be densified, usually pressurized during the reaction.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,Bohong tribeGalvanized square pipe factory, but not lower than - ℃.Stage ( & mdash; )Bohong tribeSpraying (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.For transportation: water supply, drainage, sewage treatment engineering mud transportation, marine water transportation.In recent years, large-diameter seamless square tube plays a good role in economic development. Because there are many types of large-diameter seamless square tubes, the continuous casting process of large-diameter seamless square tubes is also different. What are the specific steps of the continuous casting process of large-diameter seamless square tube? As the name suggests, square tube is a kind of square tube type. Many materials can form square tube body. Its medium is used for what purpose and where it is used. Most square tubes are steel tubes, which are unpacked, leveled, crimped and welded to form round tubes, Then the round pipe is rolled into a square pipe, and then cut into the required length. Generally, square tubes per package are mostly in large specifications in terms of spot, and . - ~~ - square tubes are divided into structural square tubes, building square tubes, mechanical square tubes, etc. according to their uses.