According to metallographic classification, the annealed state of square tube: A. hypoeutectoid steel (ferrite + pearlite); b. Eutectoid steel (pearlite); c. Steel precipitation through a common square tube (pearlite + cementite); d. Ledeburite steel (pearlite + cementite).According to metallographic classification, the annealed state of square tube: A. hypoeutectoid steel (ferrite + pearlite); b. Eutectoid steel (pearlite); c. Steel precipitation through a common square tube (pearlite + cementite); d. Ledeburite steel (pearlite + cementite).Veracruz,Chemical polishing: less investment in processing equipment, high speed, high efficiency and good durability. Its defects are poor brightness, gas overflow, demand for ventilation equipment and difficult heating. It is suitable for processing small batch of disordered parts and products with low brightness demand for small parts.Square pipe for conveying flammable and non flammable fluids, Standard No.: gbt (gbt - ). The representative material is l-l pipeline steel. It is mainly used to transport flammable and non flammable fluids. Low pressure or high pressure square pipes have high requirements. The purpose of large-diameter qb square pipe is qb square pipe,VeracruzGalvanized square pipe 50, 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 have increased significantly in recent years and become the first choice for plant construction. 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, the time is slow, the work progress is affected, and the investment is large. For some small and medium-sized enterprises Said that if the investment in the plant is too high, C-section steel and H-section steel has the characteristics of time saving, money saving and fast use. Therefore, 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.Namyangju,Solution treatment and nondestructive testing sand rolling treatment and sand blasting treatment many manufacturers in the market do not do solution treatment and % penetration nondestructive testing, and many of them use sand blasting instead of sand rolling. After these steps are omitted, the cost is greatly reduced.B. tool steel: (a) carbon tool steel; (b) Alloy tool steel; (c) High speed tool steel.When sand blasting or manual mechanical derusting is used, due to the falling off of the oxide scale of the galvanized square pipe, the metal on the surface of the galvanized square pipe is directly exposed in the air. If a primer is not applied in time, the surface of the galvanized square pipe is easy to rust again, affecting the adhesion of the paint film. I am engaged in all kinds of square tubes, square rectangular tubes, galvanized square tubes, galvanized tubes and other materials all year round. I operate in good faith. Welcome to call! As the paint is a time-effective material, the overstock of inventory is easy to expire. Therefore, the main indexes of the paint must be rechecked before use, and the paint can be used only when the results meet the standards.

Stage ( & mdash; )Chemical polishing: less investment in processing equipment, high speed, high efficiency and good durability. Its defects are poor brightness, gas overflow, demand for ventilation equipment and difficult heating. It is suitable for processing small batch of disordered parts and products with low brightness demand for small parts.For gas transmission: gas, steam and liquefied petroleum gas.Encyclopedic knowledge,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, cold drawing or cold drawing of reinforcement or low carbon steel wire rod is often carried out on site or prefabricated component factory, so as to improve yield strength and save steel.For structure: as pile driving pipe and bridge; pipe for wharf, road and building structure, marine pile driving pipe, etc.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.

Fatigue strength, plasticity and hardness discussed above are indicators of the mechanical properties of metals under static load. In fact, many machine parts work under cyclic load under which fatigue will occur.Inspection items,Square tube heating process square tube calculates the chip thickness of workpiece. After each regrinding, the service life of the saw blade. Regrinding times of the saw blade. When the saw blade is replaced, the main drive AC motor spindle rotates stepless speed change AC motor feed capacity stepless speed change feed fast return to a constant value center system brush device hydraulic saw cutting system system system represents the quality RA flatness, large burr height cutting Chip length tolerance dimension: width and length . ~ .mm ~ m ~ ~ min kW ~ rpm ( kw ~ mmmin mmmin .kw .kw & times; kW S & mu; m . mm & plusmn; mm about mm about mm about mm high. The total weight of each billet square tube is seconds (including, pipe blank cutting, saw blade return, opening device, pipe blank discharge, but excluding pipe blank transportation time). The large production capacity of the three saws is T / A. the pipe blank saw has a special reversing device (hydraulic servo device) to reduce vibration and improve the service life of the saw (only during feeding). The sawing machine has two devices distributed at the inlet and outlet (the input area is supported by roller table to ensure the bending of billet) The inlet end after sawing. Open it to ensure that the saw blade does not contact the blank when it returns. & mdash; feed saw gear & mdash; saw gear vibration reduction, which is composed of a fixed gear vibration reduction,VeracruzQ235 square tube, as a movable vibration reduction to avoid the axial of the saw blade. & mdash; brush and sweep device & mdash; a driving brush and sweep device is installed at the bottom of the saw blade to clean the iron filings on the teeth and will not affect the service life of the saw blade. &Mdash; saw blade. In order to improve the service life of the saw blade, a small amount of high load agent container is atomized by air and poured on the saw blade without residue. & mdash; saw blade cooling device. A special nozzle is used to spray cold air at - oC on the saw blade. The cut-off blank is transferred to the buffer chain in front of the loader after passing through the outlet roller table and weighing device (Note: # before sawing, there is a feeding bench for single size billets that need to be cut, and after weighing, there is a feeding bench for returned billets). The buffer transfer chain transports the billets to the lower roller table of the loader. The billets are turned over from the chain to the roller table by the turnover hook. The weighed qualified billets are loaded into the annular furnace by the loader, and the weighed unqualified billets are transported from the roller table to the removal bench for removal.The square tube represents the large capacity of the metal material under the action of tension and the calculation formula is: where: FB -- the strong force borne by the sample when it is broken, n (Newton); So -- original cross-sectional area of sample, mm. Yield point (& sigma; s) the stress of metal material with yield phenomenon when the specimen can continue to elongate without increasing (keeping constant) the force during the tensile process, which is called the yield point.If the test results of square tubes fail to meet the provisions of product standards, the unqualified ones shall be selected, and double the number of samples shall be taken from the same batch of square tubes for re inspection of unqualified items. If the re inspection results (including any index required by the test of the project) are unqualified,The other is designed with deformation angle re inspection is not allowed: A. There are white spots in the low magnification; b. Microscopic.Veracruz, which can be regarded as DEG from round tube to square tube; To & deg; The bending deformation of angle, so the deformation angle & theta; It can accurately reflect the deformation degree of corners and edges. In the design process, considering the influence of dimensional accuracy and metal work hardening, the distribution of deformation angle is usually larger at the beginning and middle passes, and then gradually decreases. In the pass formed directly by arc intersection, the fillet part of the pipe blank cannot be filled with the pass, so the pass perimeter is different from that of the pipe blank. In order to ensure the dimensional accuracy, the fillet part of the pass needs to be corrected and calculated. Therefore, this method has higher design accuracy than other methods. However, due to the large amount of iterative calculation, this method is more suitable for pass design by computer. If you use a frame that deforms both horizontally and vertically, you can directly use the deformation angle & theta; Pass design.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.For improper stamping direction simulation software shall be used in the initial stage of design to ensure that the direction of stamping parts is analyzed, and when the high-quality requirements of components require the re development of molds, the direction shall be adjusted to seamless square tubes. The square tube manufacturer introduces the forming,VeracruzGalvanized square pipe joint fittings, bending and bending of square tubes. As the name suggests, the bending is compacted, and the inner and outer rollers are double with the inner and outer walls of tube billets during actual bending Compact towards the.