It is the process of drawing the die hole of the rolled metal blank (shape, pipe, product, etc.) into a section to reduce the length and increase. It is mostly used for cold processing.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.Hiller,The strength,HillerPrice of galvanized square pipe 40, plasticity and angle discussed later are the machine function indicators of metal under static load. In practice, and the whole opportunity is tired in this environment.The reason why it is divided into two types is that chemical cleaning can only clean the surface very thoroughly, and it is difficult to achieve the desired results in some fine cracks.Semporna,For structure: as pile driving pipe and bridge; pipe for wharf, road and building structure, marine pile driving pipe, 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.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.

The disadvantage of empty bending is that when the upper side and side are synchronously empty bending, the forming force is easy to exceed the critical point due to the pressure generated by the upper roll and the lower roll at the same time, resulting in edge instability and concave, and will also affect the stable operation and forming quality of the unit. This is also the different characteristics of qb square tube and round tube empty bending. The concept of square tube: square tube is the pressure processing of ingot, billet or square tube Make materials of all shapes, sizes and properties we need.Brinell hardness, Rockwell hardness and Vickers hardness are commonly used.The principle of straightening machine is that a disc is divided into two sides to clamp round steel straight lines. Professional square tube, square rectangular tube, seamless square tube, galvanized square tube, galvanized tube, high price, service, honest operation! The edge is one with radius r, and the other outer edge must be two equal diameters with radius R. The diameter of the reinforcement to be straightened is D, and the center distance between them is adjusted to R + R + D.Manufacturing cost,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.Cold drawn or cold rolled precision square tube (gb-) is a cold drawn or cold rolled precision square tube with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. The selection of precision square mechanical structure or hydraulic equipment can greatly save machining hours, improve material rate and improve product quality.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.

At this time, if the welding wire of the same material is used for spot welding where the thickness is insufficient,HillerGalvanized pipe thickened pipe, ground and sandblasted, and repair welding shall be adopted where there are cracks, even if the steel pipe with another large opening can be made up at one time.management,B. low alloy structural steel C. ordinary structural steel and high-quality steel for specific purposes (including high-quality steel)Strength refers to the function that the square tube data is destroyed under static load (appropriate amount of plastic deformation or fracture), because the action form of load includes tension, compression, meandering shear and so on, because the strength is also divided into tensile strength, compressive strength, flexural strength, shear strength and so on. There is often a definite connection between various strengths. In normal use, tensile strength is often used as the fundamental strength gauge.Comprehensive classification ordinary steel A. carbon structural steel: (a) Q (b) Q (b); (c) Q( C)； (d) Q( B)； (e) Q.Hiller,Engaged in square tube, square rectangular tube, seamless 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, and its purpose is limited to general low pressure fluid.Steel for construction and engineering according to the classification of use without phase transformation or partial phase transformation of square tube: A. ordinary carbon structural steel; b. Low alloy structural steel; c. Steel reinforcement.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, etc. Therefore, 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,HillerPrice list of galvanized pipe, 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, if we can think about those higher metal products, 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.