High quality steel (P & le; .%, S & le; .%)Welding seamless welding seamless is to make welded elbows. After grinding and pickling, sand blasting, there is no sign of welding on the surface. Even using advanced flaw detection equipment, it can not be seen that they are welded elbows.Vega,D. do not cut your hands boring, especially for girls. Holding or fingers will bind themselves.Square tubes for low and medium pressure boilers (gb-) are high-quality carbon structural steel hot-rolled and cold drawn (rolled) square tubes for superheated steam tubes, boiling water tubes for low and medium pressure boilers of various structures and superheated steam tubes, large smoke tubes, small smoke tubes and arch brick tubes for locomotive boilers. Square tubes for high-pressure boilers (gb- is a high-quality carbon steel, alloy steel and stainless heat-resistant steel square tube for the heating surface of water tube boilers with high pressure and above. High pressure square tube for chemical fertilizer equipment (GB - is a high-quality carbon structural steel and alloy steel square tube suitable for chemical equipment and pipelines with working temperature of - ~ ℃ and working pressure of ~ mA.Jamsa,In this period, the technology of continuous rolling pipe was not mature.Normalized: A. pearlite steel; b. Bainitic steel; c. Martensitic steel; d. Austenitic steel.Mechanical engineering, power plants, agricultural and chemical machinery, glass curtain walls, automobile chassis, airports, boiler construction, highway railings, housing construction, pressure vessels, oil storage tanks, bridges, power station equipment, heavy transportation machinery and other welded structural parts with high load, etc. Process classification: according to the production process, square tubes are divided into hot-rolled seamless square tubes, cold drawn seamless square tubes, seamless square tubes and qb square tubes.

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, 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.Section shape classification square tube is classified according to section shape: simple section square tube: square tube rectangular square tube.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, 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, we can put them into the warehouse for very good retention. According to geographical conditions, 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.Inspection standard,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.It is good to purchase Baosteel's materials for cold drawing of square tubes, because Baosteel's materials are subject to grade flaw detection, and the density of steel is relatively good. After cold drawing and heating, it is convenient to line up. The steel is cold drawn at room temperature to produce plastic deformation, so as to improve the yield strength. This process is called cold drawing strengthening. Square tube is generally used for product parts with high requirements. It has good willfulness and strength. The surface is better after cold drawing. Cold drawing principle.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.

Hardness 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.Information recommendation,Square tubes for low and medium pressure boilers (gb-) are high-quality carbon structural steel hot-rolled and cold drawn (rolled) square tubes for superheated steam tubes, boiling water tubes for low and medium pressure boilers of various structures and superheated steam tubes, large smoke tubes, small smoke tubes and arch brick tubes for locomotive boilers. Square tubes for high-pressure boilers (gb- is a high-quality carbon steel, alloy steel and stainless heat-resistant steel square tube for the heating surface of water tube boilers with high pressure and above. High pressure square tube for chemical fertilizer equipment (GB - is a high-quality carbon structural steel and alloy steel square tube suitable for chemical equipment and pipelines with working temperature of - ~ ℃ and working pressure of ~ mA.When cutting the square tube, there will be deformation, uneven incision and crack of the incision. What should we pay attention to when cutting the square tube and how to operate it? Today,Because the green billet can be pressed into any shape, it is easy to weld the square tube into difficult products.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,Vega100 galvanized 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, 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, steel beam and column, 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, 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. 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.Engaged in square tube, square rectangular tube, seamless square tube, galvanized square tube, galvanized tube, old brand, price advantage and quality guarantee! However, 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.