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.Brinell hardness (HB), Rockwell hardness (HRC) and Vickers hardness (HV) are commonly used.Wells,Square tube has good machinability, good cold deformation plasticity and weldability; In addition, the toughness of steel does not decrease much during heat treatment, but it has quite high strength and wear resistance, especially when water quenching; However this steel has great resistance to white spots, temper brittleness and overheating during heat treatment.Precision pipe is a seamless pipe with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. The selection of precision seamless mechanical structure or hydraulic equipment can greatly save machining hours, improve material rate and improve product quality. Seamless pipe can be divided into hot rolled pipe and cold rolled pipe according to different productionSabah as Salim,Engaged in square tube, square rectangular tube, seamless square tube, galvanized square tube, galvanized tube, old brand, the Demander shall cut off the interface pipe when using it. The weight of short length and non fixed length products shall not exceed % of the total delivery. For qb square pipe with theoretical weight greater than kgm, it shall not exceed % of the total delivery. The bending degree of qb square pipe shall not be greater than mm per meter, and the total bending degree shall not be greater than .% of the total length. Galvanized qb square pipe for low-pressure fluid transmission, with standard number of gbt-. Representative materials: QA, qbqb, etc. It is mainly used for conveying water, gas, air, oil and heating hot water or steam, and its purpose is limited to general low pressure fluid.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 weldingFunctional index analysis of qb square tube - commonly used are Brinell angle (HB), Rockwell angle (HRC) and Vickers angle (HV) of qb square tube. 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.

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.Yield point of square tube (& sigma; s): the stress of metal material with yield phenomenon when the sample can continue to elongate without increasing (maintaining constant) the force during the tensile process, which is called the yield point. If the stress decreases, the upper and lower yield points shall be distinguished. The unit of yield point is nmm (MPA).The first is to remove the rust of the square tube. When removing the rust of the square tube, the steel wire brush is mainly used to polish its surface,WellsNational standard galvanized pipe,The difference between hot-dip galvanized square pipe and cold-dip galvanized square pipe is mainly from the following aspects: the appearance of hot-dip galvanized square pipe is slightly rough compared with cold-dip galvanized square pipe; The appearance of cold galvanized square pipe is smooth and bright.For structure: as pile driving pipe and bridge; pipe for wharf, road and building structure, marine pile driving pipe, etc.The second is the pickling of the square pipe. Both chemical and electrolytic methods are used when pickling the square pipe. These two methods can remove the oxide skin of the square pipe.

Structural stainless steel square pipe (gbt-) is a hot-rolled (extruded, expanded) and cold drawn (rolled) square pipe made of stainless steel for corrosion-resistant pipes, structural parts and parts widely used in chemical, petroleum, light textile, food, machinery and other industries.The cheapest,Hot dip galvanized square tube is a kind of square tube which is welded after using steel plate or steel strip to curl and form,WellsWhere to buy galvanized square tube, and on the basis of this square tube, the square tube is placed in the hot dip galvanized pool and formed through a series of chemical reactions; The production process of hot-dip galvanized square pipe is relatively simple, but the production efficiency is very high and there are many specifications and varieties, but this kind of square pipe needs little equipment and capital, which is more suitable for the production of small galvanized square pipe manufacturers.Performance index analysis of square tube - plasticity refers to the ability of metal materials to produce plastic deformation without deformation under load.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 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.Wells,With the improvement of production quality, the quality of square tubes is getting better and better. The quality of square tubes will affect our lives. Because the functions of square tubes are different, their characteristics and uses are different. I will introduce the characteristics and uses of square tubes in detail.Square tube, modified square tube,WellsGalvanized round pipe manufacturer, 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, 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, excessive stress concentration often shows microcracks in the bending process of profiles, 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.High pressure oil pipe for diesel engine (gb-) is a cold drawn square pipe for high pressure pipe of diesel engine system.