steel pipe

　　Common surface defects of welded steel pipe : 　　 (1) layered steel 　　Layered wall steel tube means the cross section is divided into two floors, exposed steel surface showing the hierarchical vertical cracks. Some exhibits inside and outside surfaces of steel recessed or raised locally, layered rendering suddenly raised, dents or warping in and out of the weld. 　　 (2) sticky scar 　　Pipe sticky scar refers to internal and external surfaces of the massive steel focal adhesion plaques scar. 　 　(3) holes 　　Pipe through the hole refers to a local steel tube bi holes exist. 　 　(4) open welding 　　Welded steel pipe opening means through long cracks in steel welds or partial showing of. 　 　(5) Local lap welding 　　Welded steel pipe refers to a partial outer surface of the steel pipe presents a partial arc weld. 　　 (6) Welding ditch 　　Pipe welding groove is the outer surface of the steel pipe occurs through a long groove weld. 　 　(7) the collapse of welding 　　Welded ...

　　The advantages and disadvantages of welded steel pipe 　　The average wall thickness of the tube light table table high (steel exterior appearance of steel grade resolution, brightness) can be arbitrary length. Thus, it showed its economy and aesthetics in accuracy, the use of low-pressure fluid. 　　Welded steel pipe production process is simple, high production efficiency, low cost, to carry out faster. Spiral Welded Longitudinal higher than normal, can narrow the billet production of large diameter pipe, you can use the differences diameter pipe billet production of the same width. What, then with the same length of straight pipe joints compared weld length add 30 to 100%, and lower production rate. Thus, most of the smaller diameter pipe straight seam welded, large diameter spiral welded pipe for the most. 　　Classification of welded steel pipe 　　1, High frequency welded steel pipe features: tubular good, uniform thickness, internal and external burrs produced by the welding t...

　　Thermal forming manufacturing process is including large-diameter seamless hot-rolled and hot extrusion of two ways, the former is mainly used to produce composite pipe joints, which applies seamless composite pipe production. 　　Rolling is a traditional method of preparing large-diameter seamless steel pipe . Hot rolling the composite is substantially below the pressure welding, if the deformation is large enough, the pressure exerted by the roll of metal would damage the surface of the oxide film, the atomic contact with the surface, so that the two surfaces are welded together. The advantages and disadvantages of the rolling were as follows: 　　① Advantages: high productivity, good quality, low cost, and can save a lot of loss of metallic materials, and therefore is extremely wide application of composite materials production technology. Roll bonding composite sheet, 90% of the total composite plate, and is often applied to the pipe wall thickness of less than 32mm of the proces...

　　Defect of Hot-rolled Seamless Steel Pipe 　　Separation 　　Located on the inner surface of the steel pipe was vertical distribution, was raised helical, massive metal separation or break-like dissection. 　　Straight inner flap 　　Located on the inner surface of the steel pipe was vertical distribution, showing a symmetrical or a single line-shaped folded with through long, there are local. 　　Irregular hole 　　Located in the surface of the pipe was vertical distribution, ① has one or two walls 180 °out of thickening, or in the surface of the pipe and the wall thickness of the mandrel separation point has thickened shape, also known as the inner drum kit. ② steel inner garden was a hexagonal shaped uneven thickness, also called hexagon. 　　Wall contraction 　　Located on the inner surface of the steel pipe, steel transverse section thinnest steel pipe inner surface depressions, localized thinning of the wall thickness of the severe contraction almost tear. 　　Rolled scar 　　Lo...

　　Difference between LSAW steel pipe and SSAW steel pipe are followings below: 　　1. The welding process is concerned: a consistent spiral welded pipe and Longitudinal welding, straight seam steel pipe will inevitably have a lot of T-weld, and therefore the probability of the existence of welding defects has greatly improved, and welding residual T welds stress is large, the weld metal are often in three-dimensional stress state, increases the likelihood of cracks. Furthermore, according to the provisions of submerged arc process, each weld shall have the arc at the place and extinction, but in each Longitudinal seam welding ring, unable to meet the conditions, which may have a place in the extinction more weld defects. 　　2. When the pressure in the pipe to withstand, typically produces two main stress on the wall, that the radial and axial stress stress δ . Weld resultant stress δ, wherein the helix angle of the weld. 　　3. Spiral Weld Pipe degree helix angle is generally, there...

　　Large-diameter DSAW steel pipe production process mainly explained: 　　1. plate probe: used to manufacture large diameter submerged arc welded steel pipe joints straight after entering the production line, the first full-board ultrasonic testing; 　　2. Milling: Milling machine through the two-sided edge of the milling plate, so as to meet the requirements of the plate width, the plate sides parallel to the groove shape and degree; 　　3. Pre-curved side: the use of pre-bending machine pre-bending plate edge, the edge of the plate has to meet the requirements of curvature; 　　4. Forming: in the first half of JCO molding machine after the pre-bending step after several stamped steel, pressed into a "J" shape, and then the other half of the same steel plate bent, pressed into a "C" shape, forming the final opening The "O"-shaped 　　5. Pre-welding: make a straight seam welded steel pipe after forming and using gas welding seam (MAG) for continuous weldin...

　　No matter ERW steel pipe or seamless one, we should take notice for the application of these hollow section tube before we wholesale them. Customers who had experience on how to choose can purchase by themselves. For those who may confused, you can check the functions of different hollow section tube before purchasing. 　　We can clarify the hollow section steel pipe into three main application fields. 　　First of all, building structural members need it. From columns, beams, to truss member in long-span construction auxiliary structural member, we shall adopt hollow section steel pipe. 　　Then, you can see it in mechanical industries. For construction machinery, agricultural equipment, machinery frames and furniture parts, they are good helper. 　　Finally, other situations like rack, pallet, high-rise automated warehouse, etc. can use hollow section tube too. 　　 http://www.xysteelpipe.com/info/The-application-of-hollow-section-tube-is-mainly-introduced-1326-1.htm

　　 Carbon steel pipe fittings production process is similar to carbon steel tube. 　　 ① Blanking 　　The pipe materials is used primarily for pipe, process, and bars, the shape of the blank to select the cutting method based on the material properties and product. Blank shape, size and other requirements according to different process requirements. 　 　② Forming (welding) 　　For all pipe manufacturing process, the steel pipe cross-section is an indispensable process. Due to the forming process of the different products is different, you need a longer length. 　　 ③ Heat treatment 　　The heat treatment process is an important part of the pipe manufacturing. Heat treatment step of heating, insulation and cooling, eliminating the forming process of hardening, residual stress and deformation defects of metal pipe after forming the metal structure, performance of a steel pipe network, restored to the state or its performance in the deformation processing will be improved. 　　 ④ Surfac...

　　This article introduces several major types of welded pipes, including their applications and standards in detail. 　　1. Welded steel pipe for delivering low-voltage fluid (GB/T3092-1993). This kind of pipe also known as general welded pipe, or black pipe, which is mainly used for delivering low-voltage fluid, including water, oil and gas etc. The specifications of pipe are presented by nominal diameter, which is the approximation of inner diameter. Traditionally, the diameter is expressed by inches, such as 11/2 etc. Besides directly delivery fluid, the pipe is widely applied as raw pipe of galvanized welded steel pipe for fluid. 　　2. General carbon steel wire casing (GB3640-88). This kind of welded pipe is commonly applied in industrial and civil construction, and installation of electrical equipment, plays a role of a protector for electrical wires. 　　3.Straight seam welded steel pipe (YB242-63). This kind of pipe can be divided in to metric welded pipe, welded thin-walled t...

　　In the oil and gas pipeline corrosion in the construction process, straight seam steel pipe anti-corrosion surface treatment is to determine the life of one of the key factors, it is ERW steel pipe coating with the premise of whether the combined firm. The study of professional organizations, in addition to the life of the coating depends on coating type, coating quality and construction of environmental factors, ERW steel pipe coating surface treatment of life-span of about 50%, therefore, should be strictly in accordance with corrosion layer specification for ERW steel pipe surface, continually improve the surface treatment straight seam steel pipe, ERW steel pipe in addition to embroidery methods are mainly the following: 　　 1, cleaning 　　The use of solvents, emulsion cleaning steel surfaces to achieve the removal of oil, grease, dust, lubricants and similar organisms, but it can not remove the steel surface rust, oxide, welding flux, etc., so the anti-government operations o...