San-RamonDN25 
NaranjoIs JDG qq355b square tube will have excellent rolling fatigue characteristics and corrosion resistance. Wear resistance
After isothermal quenching, fracture toughness, in the subsequent production and application, qq355b square tube will be used as the material of rolling mill flap ball screw. The qq355b square tube of case hardening steel also has the surface compressive stress characteristics obtained by heat treatment,San-VicenteDN25 hot dip galvanized pipe, and its application range is expected to be improved and expanded.
Compared with other traditional pipes, square pipe supply steel pipe has lighter raw materials, high strength, good resistance, can withstand high internal pressure, sensitive application, the compression effect will lengthen the bending line longitudinally, and the metal at the bending will accumulate and thicken, which is the compression thickening effect of empty bending.
Common specifications of square tube: ~ 5 18 & times; 18× 0.4～ 5 20× 20× 0.4～ 5 25× 25× 0.6～ 0 30× 30× 0.6～ 0 34× 34×0～ 0 35× 35×0～ 0 38× 38×0～ 0 40× 40×0～ 5 44× 44×0～ 5 45× 45×0～ 0 50× 50×0～ 0 60× 60×5～ 0 70× 70×0～ 0 75× 75×0～ 0 80× 80×0～ 0 85× 85×0～ 0 95× 95×0～ 0 100× 100×0～ 0 120× 120×0～ 0 150× 150×0～ 0 180× 180×0～
.Spiral square pipe for low-pressure transmission (standard of the Ministry of petroleum), with the standard number of syt5037-2008. The representative material is q235bq345b and other carbon steel materials. It is mainly used for low-pressure transmission of water, natural gas, heating and other pipelines.
Hot rolled q355b square tube continuous casting slab or blooming slab is used as raw material heated by stepping heating furnace and descaled by high-pressure water into roughing mill. Roughing material enters finishing mill after head cutting, tail cutting and then computer rolling. After final rolling, it is rolled into straight hair coil through laminar cooling and coiler. The head and tail of straight hair curl are often tongue shaped and fish tail shaped, with poor accuracy of thickness and width, and there are often defects such as wave shape, hem, tower shape and so on. The coil weight is heavy and the inner diameter of the steel coil is 690mm.
During the storage of square tubes, pay attention to the stacking layers of square tubes to avoid local stress at the tube end caused by too many layers, resulting in radial plastic deformation and layer damage of square tubes. It is recommended that the stacking layers of smooth pipes refer to apirp 5l1-2009 Recommended Practice for railway transportation of square pipes for pipelines or apirp 5lw-2009 Recommended Practice for ship and sea vessel transportation of square pipes for pipelines. It can also be determined by test or implemented according to the safe stacking height of square pipes. The stacking layers of pipes shall be implemented according to GBT 23257-2009 polyethylene layer of buried steel pipelines.
Mechanical property is an important index to ensure the end use performance (mechanical property) of square pipe, which depends on the chemical composition and heat treatment of steel. In the steel pipe standard, the tensile properties (tensile strength, yield strength or yield point, elongation), hardness and toughness indexes, as well as the high and low temperature properties required by users are specified.
Compared with other welding, square pipe welding has many advantages, mainly because of the exothermic reaction, the material only needs to be heated below the melting point
There are many forms of heating furnace, but the ring heating furnace is mainly used. The heating furnace has an annular furnace bottom, which can rotate slowly, the blank is loaded along the diameter direction of the furnace bottom from the inlet, and can be heated and homogenized to the specified temperature when it is used at the outlet. The production process of seamless square tube is relatively slow and the heating operation especially needs patience. Because if the heating operation is not standardized, cracks, folding and eccentricity on the inner or outer surface of the tube blank will only produce waste products and defective products.
Packaging strategy.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.
The advantages of real bending are small reverse, accurate forming, and as long as the roll shape is accurate, the R of inner corner forming is more accurate. 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.
Square pipe is an important type of square pipe, which has great similarities with seamless steel pipe, which is generally used in the field of building materials and pipes. Today we tell you about the painting of square pipe. In fact, most manufacturers need to do this function,San-VicenteGalvanized square pipe 100, not only painting but also galvanizing. Zinc will precede others The base material of the square tube is corroded. If painting is not for you, it will cost you two money. If painting, it is recommended that you brush the zinc rich primer, because you brush other paints, it will corrode quickly, and then continue to corrode your zinc coating, so as to achieve the top coat on the zinc rich primer. In fact, you should brush the zinc rich primer before galvanizing
The square tube shall be painted correctly. Professional square tube, square rectangular tube, seamless square tube,San-Vicente35 square tube, galvanized square tube and galvanized square tube have stable, safe and reliable performance and can be maintenance free. The technical level has reached the domestic level and the advanced level of similar international products. Otherwise, the square tube will be corroded. The correct paint shall also be selected during painting, so as to ensure that the square tube can be used more firmly, So as to ensure that the square tube will be better and better in future use. The square tube is widely used in the soul. Each kind of square tube has different functions for the other tube. We choose the right way and different square tubes, which can increase the performance of the square tube and be applied to different fields. Let me briefly introduce the lower tube.
Where to sell API.Today, with the development of the world, all fields are coming rapidly, which makes the demand for square tube higher and higher and the requirements of customers for square tube higher and higher. Now we are studying a new square tube. The following mainly introduces the performance of square tube in tensile strength.
With the progress of the times and the faster and faster economic development, the places where large-diameter seamless square tubes are used are becoming more and more popular
Strength refers to the function that the square tube data is destroyed under static load (appropriate amount of plastic deformation or fracture), because the action form of load includes tension compression, meandering shear and so on, because the strength is also divided into tensile strength, compressive strength, flexural strength, shear strength and so on. There is often a definite connection between various strengths. In normal use, tensile strength is often used as the fundamental strength gauge.
San-Vicente.In the heat exchange planning of metallurgy, petrochemical and other occupations, there are various forms of heat exchangers, but the conventional heat exchangers have many disadvantages, such as poor heat exchange, difficult cleaning, large dust thermal resistance and so on, which can not meet the needs of production customers. The square tube heat exchanger based on square tube throat has the advantages of excellent heat exchange, easy cleaning, small dust thermal resistance and compact structure.
When the square tube is processed, it needs to be properly polished to ensure durability, smoothness and. There are kinds of polishing for general stainless steel profiles, including mechanical polishing, open square tube, corrugated square tube and special-shaped square tube.