Brinell hardness (HB), Rockwell hardness (HRC) and Vickers hardness (HV) are commonly used.After cold drawing and aging treatment, the yield point is improved the tensile ultimate strength is also increased, and the plasticity continues to decrease. Due to the reduction of internal stress during aging, the modulus can be basically restored. According to this principle, so as to improve yield strength and save steel.Zelaya,The difference between qb square tube and QA is that there are fewer impurities s and P and better low-temperature impact performance. From the welding point of view, when the impurity elements in the base metal are less, it is good for welding hot crack.The disadvantage of empty bending is that during synchronous empty bending at the upper and side, due to the pressure generated by the upper roll and the lower roll at the same time, the forming force is easy to exceed the critical point. All kinds of square tubes, square rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes have formal qualifications. Welcome to telephone inquiry and sincerely invite cooperation! It will cause edge instability and concave, and will also affect the stable operation of the unit and forming quality. This is also the different characteristics of qb square tube and round tube empty bending.Cape VerdeHundreds of degrees Celsius, which can save energy.High density may not be obtained by simple pressurization, and insulation shall be carried out at the same time.High density may not be obtained by simple pressurization, and insulation shall be carried out at the same time.

Square pipe for conveying flammable and non flammable fluids, C-shaped steel and H-shaped steel. It is mainly used in the construction of simple plant steel structure and other infrastructure. Qb square pipe is generally used as the frame and purlin of the plant. C-shaped steel Steel is an important support for the plant, and H-section steel is used as load-bearing. Especially in recent years, a large number of small and medium-sized enterprises have started to build spacious and bright plants. If traditional buildings are built, the time is slow, the work progress is affected, and the investment is large. For some small and medium-sized enterprises, if the investment in the plant is too high, the capital will be produced after operation Serious impact. The plant built with qb square tube, C-section steel and H-section steel has the characteristics of time saving, money saving and fast use. Therefore, the sales of qb square tube, C-section steel and H-section steel are mainly used in the construction of simple plant, steel structure and other infrastructure The qb square tube is used as the frame and purlin of the plant. The C-shaped steel is used as the important support of the plant, and the H-shaped steel is used as the load-bearing. Especially in recent years, a large number of small and medium-sized enterprises around the country have started to build spacious and bright plants. If the traditional buildings are built, the time is slow, the work progress is affected,ZelayaEmbedded galvanized steel pipe, and the investment is large. For some small and medium-sized enterprises Said that if the investment in the plant is too high, it will have a serious impact on the capital after operation. The plant built with qb square pipe, money saving and fast use. Therefore, the sales of qb square pipe, C-section steel and H-section steel have increased significantly in recent years, becoming the first choice for plant construction. Large diameter qb square pipe plant is introduced Shao measures for effective wrinkle of seamless square pipe: check the wrinkle state, even when the wrinkle around the part is determined to be less than the clamping force, and the gradual increase of the roll gap force can be. When drawing the cone and hemispherical components, it should be increased to increase the inner diameter of the inner plate and the tensile stress of the wrinkle drawbead. Adopt the principle of loosening after tightening to loosen after tightening and ask Question.Hardness test is to determine the hardness of seamless qb square pipe by slowly pressing a hard indenter on the sample surface according to the specified conditions, and then testing the indentation depth or size.Square pipe is the name of square pipe, that is, steel pipe with equal side length. It is made of rolled strip steel after process treatment.Pursuit of excellence,Improve the positioning and pre bending steps, if necessary, to ensure that the web hunting problem does not occur when pressing parts. Change the shape of the surface pressure of the material to ensure the quality of the parts and avoid the non movement of the surface shape of the roll gap, resulting in uneven walking feeding.Square tube is made of different materials. It needs qualified inspection by relevant staff before leaving the factory. Square tube has a wide range of uses. Its main field is not only the construction industry, but also can be seen everywhere in our daily life. The service life of square tubes is mainly affected by surface treatment. I will explain the specific operations of surface treatment of square tubes.The disadvantage of solid bending is that it has tensile thinning effect. The actual bending will produce tension at the bending point, and the tensile effect will shorten the longitudinal length of the bending line; The metal at the real bend will become thinner due to stretching.

Square tube has a wide range of application fields. Its main field is the construction industry, which promotes the development of economic construction. Because the production process of square tube hole is different, the production design of square tube hole is also different. Next, I will introduce in detail the types of tube hole design below.High quality brand,Derusting grade for the construction process of epoxy, ethylene, phenolic and other coatings commonly used for square pipes, the surface of square pipes is generally required to reach near white grade (SA). Practice has proved that almost all oxide scale, rust and other dirt can be removed by using this derusting grade, and the depth of anchor grain can reach ~ & mu; m, which fully meets the requirements of adhesion between layer and square pipe The shot derusting process can meet the technical conditions of near white level (SA) with low operation cost and stable and reliable quality.Surface adhesion resistance is an important feature of square tubes. At present, square tubes are mostly used for transportation,ZelayaGalvanized water pipe, so the adhesion resistance makes square tubes not stick during transportation.C. electric furnace steel: (a) electric arc furnace steel; (b) Electroslag furnace steel; (c) Induction furnace steel; (d) Vacuum consumable furnace steel; (e) Electron beam furnace steel.ZelayaGenerally, chemical and electrolytic pickling are used for pickling treatment. Only chemical pickling is used for pipelines, which can remove oxide scale, rust and old coatings. Professional square tubes, rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes are safe, environmentally friendly and economical! The products are exported to foreign countries and are deeply trusted. Sometimes they can be used as reprocessing after sand blasting and rust removal. Although chemical cleaning can make the surface reach a certain cleanliness and roughness, its anchor lines are shallow and easy to pollute the environment.Zinc layer thickness: there is a great difference between cold galvanized square pipe and hot galvanized square pipe in galvanizing process; Cold galvanized square pipes are prone to & ldquo; Electric burning & rdquo; The color of this part is gray and the zinc layer is thick. It is easy to form a current dead angle at the corner, resulting in an under current area. The zinc layer at this part is thin, and there is no zinc layer attached to the cold galvanized square pipe. The cold galvanized square pipe has no zinc lump and caking as a whole,ZelayaGalvanized square pipe Q1, and the thickness of the outer wall zinc layer is μ m-μ m. The and outer walls of the hot-dip galvanized square tube are attached with zinc layer, and there will be water marks and a few zinc tumors, but the overall zinc layer is thick and the thickness of the zinc layer on the inner and outer walls of the square tube is -mu; M above. The nature of QB square tube!The advantage of empty bending is that it can bend the side length when the real bending cannot be carried out, such as synchronous bending and finishing of the upper side and side of qb square tube. Empty bend can also bend R & amp; amp; lt; .T without fracture of pipe wall.