B. converter steel: (a) acid converter steel; (b) Basic converter steel. Or (a) bottom blown converter steel; (b) Side blown converter steel; (c) Top blown converter steel.Stage ( & mdash; )St. ThomasThe 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, but not lower than - ℃.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, 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, shipbuilding, automobile, steel beam and column, special purpose, 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.Cu Chi,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,St. ThomasHow many galvanized steel pipes in a bundle, improve material rate and improve product quality. Seamless pipe can be divided into hot rolled pipe and cold rolled pipe according to different productionEngaged 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.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.

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.In order to ensure excellent coating quality, the coating is required to be firmly attached to the surface of the coated object. This depends on the quality of the coating itself; On the other hand, it depends on the quality of the coated surface treatment before construction. After various surface treatments, the coating quality and economic effect are very different.B. spring steel C. bearing steel tool steel: A. carbon tool steel; b. Alloy tool steel; c. High speed tool steel.manufacturer,In the square tube production process of welding before forming, the forming is mainly completed by the sizing frame. The sizing machine is generally a two high mill, including horizontal frame and vertical roll frame. At present, there are mainly two kinds of square pipe pass design: one is the horizontal frame is designed according to the box hole, the frame is an elliptical hole, and the other frames are approximately rectangular holes. The pass section is composed of circular arc. Professional projects include: square pipe, square pipe,St. Thomas25mm galvanized square pipe, seamless square pipe, galvanized square pipe, galvanized pipe and other related businesses. Please welcome merchants who want to have this business. And the arc radius increases frame by frame, The fillet radius of the joint between the side wall and the bottom of all pass patterns is equal to the fillet radius of the finished section. The total elongation coefficient of the square tube is about , which is mainly distributed on the flat roller. The deformation of the vertical roller is very small, and its function is to press down the short side of the square tube. With this design, the calculation is complex and the calculation value is not accurate enough. It is necessary to constantly correct the pass circumference.Change to square pipe: 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, it is easy to weld the square tube into difficult products.

Purpose of square tube the purpose of square tube includes construction, machinery, steel construction and other projects, shipbuilding, steel structure engineering, electric products ( pieces)Inspection requirements,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,St. ThomasOuter diameter of galvanized pipe, which is more suitable for the production of small galvanized square pipe manufacturers.The welding sequence is to reduce deformation. The welding sequence of rectangular butt welding shall adopt layered and symmetrical skip welding from the middle to both sides according to the following principles. The welding deformation is smaller than that of straight through welding, which is conducive to the dispersion and release of stress and avoid complex stress in weldments. During straight through welding, the narrow plastic deformation zone formed at the beginning of welding only occurs once. Moreover, due to continuous welding, the heat input is large, the heating area is large, and the plastic deformation area caused by compression is large, so the shrinkage deformation after welding is very large. In case of layered and segmented skip welding, the section of each layer is very small, and the heat required is small, and each layer is divided into several sections for skip welding. Each welding section basically re establishes the secondary temperature field on the cold steel plate, and a narrow plastic deformation zone appears each time. Therefore, the average width of the plastic deformation zone (i.e. the size of transverse shrinkage) is smaller than that of the corresponding layered straight through welding, and the longitudinal shrinkage is also smaller, The welding deformation is smaller than that of continuous filling.Square tube for automobile half shaft sleeve (gb-) is a high-quality carbon structural steel and alloy structural steel hot-rolled square tube for automobile half shaft sleeve and drive axle housing.St. Thomas,The reason why the surface of fake and shoddy materials is easy to crack is that its blank is adobe with many air holes. During the cooling process, the adobe has cracks due to the action of thermal stress, and there are cracks after rolling.Welding is a synthetic gradient material, which can be used as solder to weld special-shaped materials in order to overcome the mismatch of chemical, mechanical and physical properties between base metals.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 this kind of square pipe needs little equipment and capital, which is more suitable for the production of small galvanized square pipe manufacturers.