Puyang special rectangular tube manufacturer Wholesale direct sales manufacturer
The quality of seamless square tube is better and the price is more expensive. The welded square tube is welded by bending the plate. There is high temperature in the welding process, which will affect the metal structure, and its mechanical properties are not as stable as seamless steel tubes. Welded square tube is a hollow square section steel square tube, also known as hollow cold-formed steel. It is a square section steel with overall dimensions made of hot rolled or cold-rolled strip steel or coil steel by high-frequency welding after cold bending and forming. In addition to the thickening of the wall thickness, the size of the corner and the straightness of the edge of the seamless square tube have reached the extent that they exceed the resistance welded cold formed square tube. The size of the R corner is generally between 2 and 3 times of the wall thickness. It can also consume R corner square tubes of the size required by customers according to their needs. Seamless square tube is a kind of long steel with hollow section and no seams around. It is a square tube formed by extrusion of seamless tube through four sides of the mold. The square tube has a hollow section and is widely used as a pipeline to escort fluid. It is mainly used in liquid escort, hydraulic support, mechanical structure, medium and low pressure and high pressure boiler tubes, heat exchange tubes, gas, oil and other industries. It is more stable than welding and will not show cracks.
Puyang special rectangular tube manufacturer Wholesale direct sales manufacturer
1. Seamless square tube electrochemical coloring method: refers to the color of the film formed by electrochemical oxidation in a specific solution. 2. High temperature oxidation coloring method: immerse the workpiece in a specific molten salt and adhere to the corresponding process parameters, so that the profiled tube can form a certain thickness of oxide film and show various colors. 3. Chemical oxidation coloring method: refers to the color of the film formed by chemical oxidation in a specific solution, including salt method, mixed sodium salt method, sulfuration method, acid oxidation method and alkaline oxidation method. The common bacteriological method is widely used, but to ensure the color difference of a batch of products, reference electrodes must be used for control. 4. Gas phase cracking coloring method: it is relatively complex, and is rarely used in the industrial consumption of seamless square tubes. 5. Chemical method of ion stacking oxide coloring method: put the stainless steel seamless square tube in the vacuum coating machine to stop vacuum evaporation coating. This method is suitable for processing large quantities of products because of its large investment and high cost.
Puyang special rectangular tube manufacturer Wholesale direct sales manufacturer
1. Performance index analysis of rectangular tube - plasticity: plasticity refers to the ability of metal materials to produce plastic deformation (permanent deformation) without destruction under load. 2. Analysis of performance index of rectangular tube - hardness: hardness is a pointer to weigh the soft and hard level of metal data. At present, the commonly used method for measuring hardness in consumption is the indentation hardness method, which uses an indenter of geometric shape to press into the surface of the metal data to be tested under load, and determines the hardness value according to the indentation level. 3. Performance index analysis of rectangular tube - fatigue: the strength, plasticity and hardness discussed above are all mechanical performance indicators of metal under static load.
Puyang special rectangular tube manufacturer Wholesale direct sales manufacturer
① The rectangular straight pipe must be manufactured on the special import assembly line to ensure the manufacturing accuracy and airtightness of the air duct. ② The blanking of rectangular air duct fittings shall be completed automatically by using computer software on the imported special machine, and the automatic plasma cutting process shall be completed on the imported special plasma cutting machine for sheet metal. ③ The seam connection of rectangular air duct shall adopt the imported automatic occluder to stop the occluding process. ④ The connection between the rectangular air duct body and the plug-in flange shall adopt the rivetless connection process, and the imported equipment shall be used to stop the rivetless connection process. ⑤ The connecting flange of rectangular air duct shall adopt the connecting process of connecting plate flange and plug-in flange. When the length of the large side of the air duct is less than or equal to 2000mm, the connecting method of common plate flange shall be adopted. When the length of the large side of the air duct is more than 2000mm and less than or equal to 2500mm, the connecting method of plug-in flange shall be adopted. The rectangular air duct shall be mechanically pressed with reinforcing bars, and the spacing between reinforcing bars shall be about 300mm.
Puyang special rectangular tube manufacturer Wholesale direct sales manufacturer
1. Solid bending: solid bending, which literally means that the bending is compacted, and the inner and outer rollers and the inner and outer walls of the tube blank are compacted in both directions during solid bending. 1) The advantage of real bending is small elasticity, accurate forming, and only accurate roll shape is required. The R of internal angle forming is relatively accurate. 2) The defect of real bending is tensile/thinning effect. 1、 The actual bending will produce tension at the bend, and the tensile effect will shorten the longitudinal length of the bending line; 2、 The metal at the solid bend will become thinner due to stretching. 2. Empty bending: empty bending is the bending moment formed by the one-way contact between the outer roll and the outer wall of the tube blank to bend the strip. Empty bending will cause the bending line to shrink, and the shrink effect will make the bending line longitudinally extend, and the metal at the bend will appear to accumulate and thicken, which is the shrink/thicken effect of empty bending. 1) The advantage of empty bending is that it can stop the bending of side length when the real bending cannot be stopped, such as the synchronous bending and finishing of the upper/side edges of square and rectangular tubes. Empty bending can also bend the inner corner with R<0.2t without breaking the pipe wall. 2) The defect of empty bending is that when the upper side/side side are synchronously empty bending, because the upper roll and the lower roll produce pressure at the same time, the forming force is easy to exceed the critical point, forming the edge instability concave, and also will affect the stable operation of the unit and the forming quality. This is also the different characteristics of square and round tubes during empty bending.
