SSAW Pipe

　　Dimensions tolerance for API 5L seamless pipe . 　　1. For outer diameters less than 2 3/8 in (60.3 mm), pipe body diameter tolerance +/-0.5 mm. Pipe end +/- 0.5 mm; Out of Roundness tolerance for pipe body is 0.9 mm (0.036 in), pipe end 0.6 mm (0.024 mm). 　　2. For OD equal or above 2 3/8 in (60.3) to 24 in (610 mm), (diameter tolerance) for pipe body is +/- 0.0075D, pipe end +/- 0.005D but max to +/- 1.6 mm (0.063mm); Roundness tolerance for pipe body ≤ 0.015D, pipe end ≤ 0.01D. 　　(In case agreed with manufacturer and client, more strictly tolerances could be applied) 　　3. For wall thickness 　　Below than 4 mm (0.0157 in), tolerance +0.6 (0.024 mm), -0.5 mm (0.020 in); 　　For API 5L seamless steel pipe thickness in 4 mm to 10 mm (0.394 in), +0.150t, -0.125t; 　　For API seamless pipe thickness 10 mm to 25mm (0.984 in), +/-0.125t; 　　Wall thickness ≥ 25 mm, +3.7mm or +0.1t (if larger) and -3.0 mm (0.120 in) or -0.1t (if larger). 　　t for thickness; 　　4. For straightness, ...

　　 Boiler tube after a long run, the inevitable emergence of scale, corrosion problems, boiler scale formation is the main reason for the water with a hardness of ingredients, through subsequent high-temperature, high-pressure continuously concentrated by evaporation occurs in the furnace a series of physical, chemical reactions, culminating in the heating surface to form a hard, dense scale. 　　Boiler tube cleaning by definition refers to remove an internal scale boiler chemicals, widely used in electric boiler cleaning, boiler cleaning oil, gas boiler cleaning, coal-fired boiler cleaning, water furnace cleaning, hot water boiler cleaning, heating boiler cleaning, boiler cleaning baths, steam boiler plate heat exchanger cleaning and cleaning and so on. 　　A portion of the boiler water after the water evaporated by heating, and had a bad dissolution of calcium sulfate (CaSO4, gypsum is calcium sulfate containing water of crystallization) precipitated. Original dissolved calcium bica...

　　 Hot rolled seamless steel tube : hot rolling is related to the cold drawn, hot rolling is performed above the recrystallization temperature of the rolling. 　　Hot-rolled seamless steel tube process: 　　Round tube perforation → heating → three-roll rolling, rolling or extrusion → detached → sizing (or reducing) → cooling → straightening → hydrostatic test (or testing) → mark → storage 　　Hot-rolled seamless steel tube advantages: 　　Ingot casting can destroy tissue, grain refinement of steel and eliminate defects microstructure, so that the steel dense tissue mechanical properties are improved. This improvement is mainly reflected in the direction along the rolling direction to a certain extent, the steel is no longer isotropic; pouring formed bubbles, cracks and loose, can be welded at a high temperature and pressure. 　　Hot-rolled seamless stee tube disadvantages: 　　1. After hot rolling, the steel inside the non-metallic inclusions (mainly sulphide and oxide, and silicates) ...

　　 OCTG pipe is a kind of upscale product made of steel pipes, and it has many kinds. There are 15 kinds of specifications for OCTG diameters, and the outer diameter ranges from 114.3mm to 508mm. There are 11 kinds of steel grades, such as J55, K55, etc. There are many types and requirements of the pipe ends' threads, and the ones which can be manufactured are STC, LC, BC and VAM, etc. The manufacturing and installation process of OCTG involve a lot of testings as follow: 　 　1. Ultrasonic Testing 　　When ultrasonic waves propagate in the tested material, acoustic characteristics of the material and changes of internal structures have a certain influence on the propagation of ultrasonic waves. We can know the changes of material's performance and structure by the influence degree and condition of the ultrasonic waves. 　 　2. Radiographic Testing 　　The radiation level of penetrating normal parts and defective parts of OCTG is different, which will cause different blackness...

　　 Seamless stainless steel pipe s treatment technology refers to the processing of achieving uniform silver with metallic luster. This is generally referred to the production of large seamless stainless steel pipes. Because large seamless stainless steel pipes is manufactured through stamping, folding and welding process, the surface of workpiece has oil, rust, macular, which is neither beautiful, and easy to rust, reducing its stainless steel quality and value. 　　To make seamless stainless steel pipes achieve the standard, the surface must be finished. After forming matte treatment, that can achieve beautiful appearance, but also improve its anti-corrosion and anti-discoloration performance. After the above method, the corrosion resistance of stainless steel seamless pipes can be increased by 2 to 3 times. 　　Seamless stainless steel pipes does not rust due to the existence of chromium, nickel components, and then through the matt treatment, not only can eliminate the matrix impur...

　　Oxyfuel and plasma cutting play an important role during the production process of making welded steel pipe like ERW steel pipe . And forgetting to grind the joint after oxyfuel or plasma cutting would be an common mistake for a new welder. 　　Today, we can make it alone to make an essay to tell all of us who need to choose steel pipes or producing tubes. Adding a layer of oxide to the cut edge during the oxyfuel and plasma cutting processes would be the necessary step for steel pipe. And here are the notices: 　　First of all, the oxide layer has to be removed prior to welding due to the higher melting point of oxide than base metal. 　　What’s more, the oxides can also remain in the weld and cause porosity, inclusions, lack of fusion and other defects. 　　In addition, welders have to keep in mind to grind the joint down to the parent material prior to welding, as well as grind the inside and outside diameters of the pipe to remove these oxides and other potential contaminants.

　　Steel pipe have a hollow section, and the length of which is much larger than the diameter or circumference. So, what steel pipe, from welded type like ERW steel pipe to seamless steel tube, can do for us? 　　Please don’t look down upon these steels, not only are steel pipes used to transport fluids and powdery solids, exchange heat energy, and make mechanical parts and containers, it is also an economical steel. 　　Steel pipe is hiding in our daily lives, we just don’t find it clearly. For example, your shoe rack, the knife you use for cooking, the tools you use for cooking. Your car, the road you go to work...there are too many and there are countless. 　　There is no doubt that we could not live well without steels. I am no even being joking! That’s all true! 　　The use of steel pipe to manufacture construction structure grid frame, prop and mechanical support can reduce the light weight, save the metal 20 / 40, and realize the mechanization of industrial construction. Making ...