The appearance of fake and inferior square tubes often has pitting. Pockmarked surface is an irregular uneven defect on the surface of square lead pipe due to serious wear of rolling groove. Due to the pursuit of profit by fake and shoddy square tube manufacturers, the rolling of rolling groove often exceeds the standard.Pig iron refers to the product made by smelting iron ore in blast furnace. It is mainly used for steelmaking and square casting. Put the cast pig iron in the melting furnace to obtain cast iron (liquid), and cast the liquid cast iron into a cast square pipe. This kind of cast iron is called cast iron.Kakani,Stainless steel qb square pipe for mechanical structure, Standard No.: gbt-. Representative materials Cr cr crni CrNi crninb, etc. are mainly used for mechanical parts and structural parts such as machinery, automobile, bicycle, furniture, hotel and restaurant decoration.The surface of galvanized square pipe treated by sand blasting, shot blasting or pickling process is relatively clean, but the derusting quality level must be reached.Kilkenny manual and mechanical derusting can be adopted which improves the adhesion of the coating. When the installation site unconditionally adopts sand blasting and shot blasting,After spraying (throwing) derusting, it can not only expand the physical adsorption on the pipe surface, but also enhance the mechanical adhesion between the layer and the pipe surface. Therefore, spray (throwing) derusting is an ideal derusting method for pipelines. Generally speaking, shot blasting (sand) is mainly used for the inner surface treatment of the pipe, and shot blasting (sand) is mainly used for the outer surface treatment of the pipe. Several problems should be paid attention to in derusting by spraying (throwing).Square pipe for conveying flammable and non flammable fluids, 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 C-shaped steel and H-shaped steel. It is mainly used in the construction of simple 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,KakaniProduction video of galvanized square pipe, 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, 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, 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, C-section steel and H-section steel has the characteristics of time saving, 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.When the vehicle is replaced with seamless square tube blank, the material is too soft to affect the requirements, so as to ensure the quality of parts and avoid wrinkles.

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.Electrochemical polishing: long specular gloss, stable process, less pollution and good durability. Suitable for mass production, it is mainly applied to high-grade products, imported products and public service products. Its processing technology is stable and the operation is simple.Section shape classification square tubes are classified according to section shape: simple section square tubes & mdash& mdash; Square tube, rectangular tube and complex section square tube & mdash& mdash; Surface treatment classification of flower shaped square pipe, open square pipe, corrugated square pipe and special-shaped square pipe square pipe is divided into hot-dip galvanized square pipe, electro galvanized square pipe, oil coated square pipe and pickling square pipe according to surface treatment. Square pipe is classified according to purpose & mdash& mdash; Square tubes for decoration, machine tools and equipment, machinery industry, chemical industry, steel structure, shipbuilding, automobile, steel beam and column and special purpose are classified by wall thickness & mdash& mdash; Super square tube, square tube and thin-walled square tube plasticity refers to the ability of metal materials to produce plastic deformation (deformation) without deformation under load.Trustworthy,The strength, plasticity and angle discussed later are the machine function indicators of metal under static load. In practice, many mechanical machines are under repeated load, ammoniated steel and surface quenching steel; (c) Easy to cut structural steel; (d) Steel for cold plastic forming: including steel for cold stamping and steel for cold heading.Mechanical engineering, automobile chassis glass curtain walls, 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.

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, head and tail cutting time, 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, 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.Quality improvement,: it refers to the processing of square tube which places metal in a closed Jane and applies pressure at the end to extrude the metal from the specified die hole to obtain finished products with the same shape and size. It is mostly used to produce non-ferrous metal materials. Square tube ferrous metal, steel and non-ferrous metal. Before introducing the classification of steel, briefly introduce the basic concepts of ferrous metal, square tube steel and non-ferrous metal.The banding caused by component segregation is difficult to be eliminated by heat treatment. Generally, normalizing can correct the segregation to the allowable level. If the banding is serious, it can be improved by multiple normalizing. It is reliable to conduct high-temperature diffusion annealing first and then normalize again, which can completely eliminate the strip, but the cost will be very high, modified square tube square tube, QB square tube and hot-rolled square tube are qualified in quality inspection. The manufacturer adopts advanced equipment to ensure the quality of each product. Magnetic flux leakage testing for surface defects of square tubes is very similar to magnetic particle testing for square tubes, and its scope of application,KakaniGalvanized Q235B square pipe, sensitivity and reliability are stronger than magnetic particle testing. Indirect square forming process the traditional forming process of cold-formed square pipe is to gradually roll the hot-rolled steel coil multi stand forming unit into round pipe at room temperature, and then the shaping unit will roll the round pipe into square pipe, which is called indirect square forming process. The traditional roll forming process uses the method of fixed bending point position and variable bending radian to complete the corner forming of pipe blank, which is suitable for rolling small and medium-sized products. Rolling with this process & ldquo; Superb & rdquo; Square tube will show its inherent defects. Because the roll work in the bending process of this process is always concentrated at the point, excessive stress concentration often shows microcracks in the bending process of profiles, which will lead to cracking in serious cases. The products with such defects have serious consequences when they are used in building steel structures. The study of the broken square tube column in the Hanshin earthquake in Japan shows that the corner microcrack is the main cause of the square tube fracture. At the same time, due to the different forming bending radians of products with different wall thickness, the universality of rolls is limited. The large-size cold-formed square tube used in the process adopts the advanced & ldquo; Direct Square & rdquo; The production process is to directly roll the hot-rolled steel coil into a square and rectangular shape at room temperature.Kakani,According to metallographic classification,Kakani30x30 stainless steel square pipe, 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).The strength, plasticity and angle discussed later are the machine function indicators of metal under static load. In practice, many mechanical machines are under repeated load, and the whole opportunity is tired in this environment.If the test results of square tubes fail to meet the provisions of product standards, 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 batch of square tubes shall not be delivered. If the following inspection items fail to pass the preliminary inspection, re inspection is not allowed: A. There are white spots in the low magnification; b. Microscopic.