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Stage ( & mdash; ). fake and inferior square tubes are easy to fold. Folding is a variety of broken lines formed on the surface of square tubes, and this defect often runs through the longitudinal direction of the whole product. The reason for the folding is that the fake and shoddy manufacturers pursue the rate, the reduction is too large, resulting in ears, folding occurs during the next rolling, the folded products will crack after bending, and the strength of the square tube will be greatly reduced.Chatham Kent,Except for the thickening of wall thickness, the corner size and edge straightness of square pipe reach or even exceedThe characteristics of square pipe are as follows: the production process of square pipe is simple, the cost is low and the development is fast. The strength of spiral square pipe is generally higher than that of straight seam square pipe. It can produce square pipe with larger pipe diameter with narrow blank and square pipe with different pipe diameter with blank of the same width. However, compared with straight seam pipe of the same length, the weld length is increased by ~, which will be oriented to the whole country for a long time Individuals and enterprises provide all kinds of square tubes, square rectangular tubes, galvanized square tubes, galvanized tubes, on-site settlement, honest operation, local offices, long-term cooperation, most of the smaller square tubes adopt straight seam welding,Chatham KentGalvanized customized square pipe, and most of the large-diameter square tubes adopt spiral welding.San-Pedro,B. low alloy structural steel C. ordinary structural steel and high-quality steel for specific purposes (including high-quality steel)The surface of fake and inferior square tubes is easy to produce scabs. There are two reasons: the material of fake and inferior square tubes is uneven and there are many impurities. The guide equipment of fake and shoddy material manufacturers is simple and easy to stick to steel. These impurities are easy to scar after biting the roll.Functional index analysis of qb square tube - commonly used are Brinell angle (HB) Rockwell angle (HRC) and Vickers angle (HV) of qb square tube. Angle is a gauge needle to weigh the soft and hard level of metal data. The angle method is rarely used to determine the internal angle in the current life. It uses the metal data surface tested under the fixed load of the indenter with a certain number and shape to determine its angle value according to the level of the object.

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 formed square tubes shall be tested to ensure that each piece is qualified. The qualified square tubes will be stored. Various problems will occur in the long-term storage. If there are problems, we need to deal with them in time. What are the reasons for the rusting and corrosion of square tubes? Let's introduce them to you next.The reason why the surface of fake and shoddy materials is easy to crack is that its blank is adobe with many air holes. During the cooling process, and there are cracks after rolling.Project scope,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.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 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.Generally speaking, square pipe welding has a process: ignition, pressurization and thermal insulation.

Hardness hardness is a pointer to measure the hardness and softness of metal materials. At present, the hardness method is commonly used to measure the hardness in production. It uses the indenter with fixed geometry to measure the hardness value of the metal material surface tested under fixed load according to the degree of hardness.offer,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.The first is the influence of external conditions. It mainly depends on the medium characteristics and temperature around the square pipe and whether the medium around the pipe is corrosive. Because the corrosivity of the medium is closely related to the microorganisms contained in the soil. And if it is a long-distance pipeline the soil environmental properties are more complex. In addition, the temperature of the environment where the pipeline is located will also affect the corrosion of the square pipe. If the temperature is high, the corrosion speed will also be accelerated, while if the temperature is low,Chatham KentGalvanized square pipe price today, the corrosion speed will be slowed down.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.Chatham Kent,Pull square tube:QB square tube is a product appeared in recent years, which mainly has strict tolerance and roughness for the dimensions of inner hole and outer wall. Production process classification of large-diameter qb square tube large-diameter qb square tube is divided into hot-rolled seamless square tube, cold drawn seamless square tube, seamless square tube and qb square tube according to production process. Among them, qb square tube is divided into: (a) by process & mdash& mdash; Arc welded square pipe, resistance welded square pipe (high frequency and low frequency),Chatham Kent16Mn galvanized square pipe, gas welded square pipe and furnace welded square pipe (b) are divided by weld & mdash& mdash; Material classification of straight seam welded square pipe and spiral welded square pipe large diameter qb square pipe: plain carbon steel square pipe and low alloy square pipe. Ordinary carbon steel is divided into Q Q q SS, # steel, # steel, etc; Low alloy steels are divided into q Mn, Q, St-, etc.Functional index analysis of qb square tube - the load on the machine parts due to the great progress of strength is called the frontal collapse load. The power of destruction of qb square tube under the frontal collapse load is called the frontal collapse toughness.