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 unqualified ones shall be selected,Port AntonioRust proof galvanized square pipe, 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.B. converter steel: (a) acid converter steel; (b) Basic converter steel. Or (a) bottom blown converter steel; (b) Side blown converter steel; (c) Top blown converter steel.Port Antonio,Pile pipe and bridge; Pipes for wharf, road, building structure, etc. It is mainly used as petroleum geological drilling pipe, cracking pipe for petrochemical industry boiler pipe, bearing pipe, high-precision structural pipe for automobile, tractor and aviation, etc.Product description of square tube square tube is a light thin-walled steel tube with hollow square section, also known as steel cold-formed profile. It is a section steel with square section shape and size, cold bending and high-frequency welding. In addition to wall thickness thickening, the corner size and edge flatness of hot-rolled special square pipe reach or even exceed the level of resistance welding cold-formed square pipe. Good comprehensive mechanical properties, weldability, cold and hot workability and corrosion resistance, and good low temperature toughness.Boende,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.Change to square pipe: generally, the strip steel is unpacked, leveled, crimped and welded to form a round pipe, then rolled into a square pipe from the round pipe, and then cut into the required length. Stage ( & mdash; )Square tubes for petroleum cracking (gb-) are furnace tubes, heat exchangers and pipeline square tubes suitable for petroleum refineries.

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 advantages of real bending are small reverse accurate forming, and as long as the roll shape is accurate, 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 tubes have different functions and different characteristics. Square tubes of various specifications, square rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes are welcome to waste merchants, industries, enterprises and power departments to visit and negotiate! Oxidation will also occur on the surface of square tubes after long-term use. What should we do if oxidation occurs? Let me give you a detailed introduction on how to remove square tubes Oxide scale.Price,Ship carbon steel square pipe (gb-) is a carbon steel square pipe for ship class I pressure pipe system, class II pressure pipe system, boiler and superheater. It is a long-term business square pipe, square pipe, seamless square pipe, galvanized square pipe and galvanized pipe. Welcome to consult. The working temperature of carbon steel square pipe wall shall not exceed ℃, and the working temperature of alloy steel square pipe wall shall exceed ℃.Square tube production most square tube processing is square tube pressure processing, resulting in plastic deformation of the processed steel (billet, ingot, etc.). According to the square tube processing temperature, the square tube can be divided into cold processing and hot processing. The main processing of square tube includes: rolling: the gap (various shapes) between the square tube metal blank and the rotating roll , because of the compression of the roll, the material section is reduced and the length is increased. This is a common production method for producing square tubes. It is mainly used to produce square tube profiles,Port Antonio4 points galvanized square pipe price, plates and tubes. It is divided into cold rolling and hot rolling.With the progress of the times and the development of science and technology, the application fields of square tubes are widely divided. The main fields are the construction industry. Affected by the environment and weather, square tubes will also rust for a long time. How to improve the rust resistance of square tubes and what are its rust resistance? Let me give you a detailed introduction below.

Square tube, 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, 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,Port Antonio4-point galvanized pipe, 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.Installation materials,The square tube for fluid transportation (gbt-) is a general square tube for transporting water, oil, gas and other fluids.For seamless qb square tubes, there is a certain hardness, so it is necessary to test the mechanical properties of seamless qb 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.Port Antonio,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.Square tube structural steel A. mechanical steel: (a) quenched and tempered structural steel; (b) Surface hardening structural steel: including carburized steel, 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.The floating mandrel mill is in its heyday