Seamless Steel Pipe

　　The casing is easy to be folded out in production, which affects the improvement of product quality and needs control. 　　There are several outer folding edge oxide particles cause segregation of elements, with a folding, an oxide middle folding, the presence of an excess of Al, Mg, Ca, S, P, Mn, Si outer folding element, particularly at the grain boundaries have 20μm so brittle inclusions SiO2 and silicates, intergranular fracture occurs, and said brittle inclusions is the main reason for the formation of the outer fold. 　 　Smelting process: 　　1) To ensure that a pull carbon hit, after avoiding blowing carbon control endpoint> 0.10%; 　　2) Increase the effect of converter slag, slag under strict control, the departure process using slag, a steel ladle slag after thickness <50mm; 　　3) Double slag operation, control phosphorus content of the molten steel. 　　 Refining process: 　　1) LF refining processing time ≥20min; 　　2) Strengthening deoxy go mixed results. Requir...

　　304 seamless steel pipe burst occurred for the following reasons: 　　1. 304 seamless polishing flatness is not enough to produce deflection. 　　2. Stripper ring true no demagnetization process before production, no return material shoot; production has broken needle spring card stock. 　　3. 304 seamless bad material in subsequent processing easily broken. 　　4. Line cutting mishandled cable wire cutting, the gap does not, did not make clear angle. 　　5. Improper heat treatment and quenching and tempering process is deformed. 　　6. The design process 304 seamless strength is not enough, the blade pitch too close to 304 seamless structure is unreasonable, insufficient number of non-template block pad pad feet. 　　7. Lamination stamping awareness of production, location is not in place, do not use blow gun, still continue to produce a template with cracks. 　　8. The selection of the tonnage punch press equipment, punching force is not enough, the next transfer mode too deeply.

　　Thick-walled lsaw steel pipe anti-rust oil to be disposed of, we must first understand the characteristics and varieties of anti-rust oil, as well as their results. So this time in the procurement of goods can not be thrown off balance, direct save time. Below let us Xiaobian to introduce walled Longitudinal creosote strengths and varieties of it. 　 　1. Quick-drying 　　Its biggest advantage of doing that is fast, rugged, use widely anticipated, it is possible to use in harsh environments, the use. 　 　2. Soft membrane 　　With paraffin oil or heavy oil disposal made, rust-proof function are the three strongest presence, and can be washed using one kind of solvent. 　　3. Film type 　　Its anti-rust function relatively handicap. But its operation is very simple disposal. Use can reduce the harm caused by their conflict, reduce costs, ensure productivity directly carried out.

　　First, reasonable selection. Precision messy mold material should choose a good micro-deformation of steel on steel carbide segregation serious mold should be a reasonable casting and heat treatment quenching and tempering, solution heat treatment on a large double refining and casting mold steel can not be carried out. Reasonable choice of heating temperature control heating rate, on messy precision molds can be heated slowly, preheating and other methods to reduce the mold uniform heating heat deformation. 　　Second, the correct operation of the heat treatment process and reasonable heat treatment process is also a useful way to reduce messy precision mold deformation. Deformation reason messy precision molds are often messy, but we only need to master the rules of the deformation, to analyze the attack reason, the choice of methods to avoid abnormal deformation of the mold can be reduced, and also can be controlled. 　　Third, precision molds to be messy pre-heat treatment, machi...

　　Oil casing surface less oxidation and decarburization induction heating quenching steel surface decarburization phenomenon are not found in metallographic observation, whereas conventional heating M0.10mm low carbon layer present on the surface after solution treatment. Oil casing oxidation amount after solution treatment, friction material surface after conventional heating solution scale, low yield. ~ 0 0.15% 20%; induction oxide Wu is not only significantly dense oxide film. 　　Mechanical properties of steel at room temperature gives the EAF steel smelting and vacuum sense, using different methods of heating the solution treatment, but also by the mechanical properties at room temperature after the same side effect of treatment comparison. 　　Data showed that dissolved after two days aging treatment inch mechanical properties at the same level. However, induction heating the steel to the amount of EAF, casing metallurgical quality far below the vacuum induction furnace steel. Th...

　　Steel thermal expansion coefficient αL.definition: the temperature rises 1 ℃, the relative elongation of objects. 　　Thermal expansion coefficient is not constant, but varies slightly with temperature, with increasing temperature. 　　Original length L1, L2 of the size warmed, ΔL is the amount of deformation (L2-L1) T1 is the original temperature, T2 is the temperature of the warmed, ΔT is the temperature difference (T2-T1) 　　Body temperature changes due to swelling phenomenon occurs called "thermal expansion." Usually refers to external pressure under the same circumstances, most of the material at elevated temperatures, its volume increases, the temperature is lowered the volume is reduced. Under the same conditions, the maximum expansion of the gas, followed by expansion of the liquid, solid minimal swelling. A small number of substances in a certain temperature range, the temperature rises, but its volume is reduced. Because the body temperature, the average kinetic ...

　　1, The metal tube, rod, wire rod detection, contact is not required and no need for a coupling medium. So high detection speed, easy to implement automated testing, especially for online P seized. 　　2, High sensitivity for the detection of surface defects, and in a certain range with good linearity indication of the size of the different defects can be evaluated, it can be used as a quality management and control. 　　3, Eddy currents are many factors, such as cracks, material, size, shape and electrical conductivity and permeability and the like. Spleen using specific circuits for processing, can filter out certain factors inhibit other factors, thereby making it possible for an individual above factors for effective testing. 　　4, Since the inspection and do not have contact with the workpiece without coupling medium, it can be detected at high temperatures. As the probe can be inserted into the distant job, so the workpiece can be narrow and deep wall area (including walls) and...

　　 Seamless pipe mechanical properties failed mainly in its low elongation and yield point is not obvious, the mechanical properties of the above-mentioned non-conforming product samples for metallurgical testing, found cold drawn pipe spherical pearlite organization and very fine grains ferrite. 　　Globular pearlite structure is a typical annealing inadequate organization. Normal cold drawing process requirements, the microstructure after annealing should be ferrite and pearlite flaky globular pearlite formation temperature is 750 ~ 830 °C, so the globular pearlite, suggesting that the low annealing temperature, annealing insufficient. 　　Extremely fine grains of ferrite is also an annealing inadequate organization, and its globular pearlite formation conditions are different. Globular pearlite is formed when the annealing temperature is low, and the very fine ferrite grain structure is appropriate at the annealing temperature and time is short form. 　　After the cold-drawn steel ...

　　Electric resistance welding method is a combination of the workpiece to exert pressure through the electrode, the use of current through the resistor thermal contact surfaces and adjacent areas generated by joint welding. 　　Advantage of Electric resistance welding 　　1, nugget, always surrounded by a plastic ring, molten metal and air separation, metallurgy process is simple. 　　2, the heating time is short, heat concentration, it is a small heat-affected zone, deformation and stress is also small, usually do not have to arrange correction after welding and heat treatment processes. 　　3, no wires, rods and other filler metals, as well as oxygen, acetylene, hydrogen, such as welding materials, welding low cost. 　　4, simple operation, easy to implement mechanization and automation, improved working conditions. 　　5, high productivity, and no noise and harmful gases, in mass production, and other manufacturing processes can be edited together to the assembly line. But due to fl...

　　First,after hot rolling, steel internal non-metallic inclusions (mainly sulfides and oxides, and silicate) is pressed into thin slices, delamination (interlayer) phenomenon. Layering the steel in the thickness direction of the tensile performance deteriorated significantly, and there may be an interlayer tears during weld shrinkage. Weld shrinkage induced local strain reaches the yield point strain often several times larger than the load caused by the strain. 　　Second, the residual stress caused by uneven cooling. The residual stress in the absence of external force internal self-equilibrium stress, hot-rolled steel sections have such a variety of residual stress, the greater the general steel-sectional dimension, the greater the residual stress. Although the residual stress from equilibrium, but still has some influence on the properties of steel members under loads. Aspects such as deformation, stability, fatigue, etc. are likely to have an adverse effect. 　 　Check www.tjxyste...

　　As we all know, each step during steel pipe(from seamless steel pipe to ERW steel pipe as well as galvanized steel pipe) production would have decisive impact on high quality of the steel pipe. 　　Today, our main topic is production control: 　　First of all, the controlling of steel pipe’s gap. Large or not would have main effect for the quality of steel pipe. Poor welding would come from the large weld control as the welds are not fused or cracked. Due to the heat is too large, the weld control is too small, this would lead to weld burns. 　　What’s more, high-frequency induction coil position control. For position, it is necessary to make the induction coil on the same center line with the steel pipe. And for the distance, it is important to make sure they are as close as possible for the front end of the induction ring and the center line of the pressing roller to the steel pipe, thus, it would reduce the strength of the weld. 　　 http://www.xysteelpipe.com/info/Production-cont...

　　Process of cold drawn seamless steel pipe 　　round tube → heating → perforation → Heading → annealing → pickling → oiled (copper) → multi-pass cold drawn (cold rolled) → blank tube → heat treatment → straightening →hydrostatic testing (testing) → mark → storage. 　　The general cold strip mills, volume should go through continuous annealing (CAPL unit) to eliminate cold hardening and rolling stress, or batch annealing reach the mechanical properties of the corresponding standard specifies. Cold rolled steel surface quality, appearance, dimensional accuracy better than hot-rolled plate, and right-rolled thin product thickness is about 0.18mm, so the majority of users favor. 　　Cold rolled steel coil substrate products deep processing of high value-added products. Such as electro-galvanized, hot dip galvanized, electro-galvanized fingerprint resistant, painted steel roll damping composite steel, PVC laminating steel plates, etc., so that the excellent quality of these products has a ...

　　The seamless tube for heat exchanger is one of the elements of the heat exchanger and is placed inside the cylinder for the exchange of heat between the two media. It has high thermal conductivity and good isothermal properties. It is a device that can rapidly transfer heat energy from one point to another, and has almost no heat loss, so it is called a heat-transfer superconductor and its thermal conductivity is several thousand times that of copper. 　　In addition to seamless tube, heat exchangers can also use a variety of enhanced heat transfer tubes, such as finned tubes, threaded tubes, spiral grooved tubes, and the like. When the heat transfer coefficient on the two sides of the inner diameter of the tube is greatly different, the fins of the fin tube should be arranged on the side with a low heat supply coefficient. 　　Commonly used sizes of heat transfer tubes (OD x wall thickness) are mainly Φ19mmx2mm, Φ25mmx2.5mm and Φ38mmx2.5mm seamless steel tubes and Φ25mmx2mm and Φ38m...

    Sleeve coupling is necessary for connecting two pipe sleeves. The manufacturing method is the same as seamless pipe , and domestic J55 and n80Q special steel products are used. The ends of the steel pipes are internally threaded to connect the upper and lower pipes. In order to ensure the tightness of the joints, the thread accuracy requirements are more stringent.     First, use     Used to connect the upper and lower lines.     Secondly, type     The domestic bushing is divided into two parts: the casing is not thickened, the casing is connected and the thicker oil sleeve is.     Three is the processing process     Automobile face - car outer ring boring - car line inspection - phosphating

    Straight seam high frequency (ERW) by welding and induction welding is divided into different forms of contact of two welding, hot-rolled wide coil as raw material, through pre-bending, continuous forming, welding, heat treatment, sizing, straightening, cutting, etc. step short compared to the spiral weld, high dimensional accuracy, uniform thickness, surface quality, under pressure advantages, but the disadvantage is that only the production of small diameter thin-walled tube, easy to produce gray leaf spot weld, incomplete fusion ditch-like corrosion defects. Currently wider field of application of city gas, crude oil and other oil products transportation.     Spiral submerged arc ( SSAW ) pipe volume is the forward direction of its centerline forming tube forming angle (adjustable) while forming side welding, weld into a helix, the advantage of the same specifications can produce a variety of diameters steel, adapt to a wider range of raw materials, the main...

    Fault erw steel pipe unit is relatively more, and the cause of the failure is also more complex, the result is often caused by a variety of reasons, can be caused by several reasons or a result.     Scratch     Tube welding machine appeared scratches caused mainly by two parts, one guide means, and second extrusion welding mechanism.     Squeeze roller scratches caused, mainly in the bottom of the tube, because generally have the following points:     (1) Does not match the pass     Weld extruded structure has two roll, three-roll and four-roll type, as long as the combination of the hole do not match, it is likely to cause the tube surface scratches, especially two roll structures. Factors that do not fit and pass a lot, a two-roll structure as an example, such as bearing damage; roller axial movement; pass sample sizes; two roller height position is not the same; shaft bending and assembly of instability and so...

    ERW (ERW straight seam welded steel pipe) is a hot-rolled coil after molding machine, the use of high-frequency current skin effect and proximity effect, so that the edge of the tube is heated to melt under the action of squeezing rollers pressure welding to achieve production.     High frequency resistance welding method used in pipe production of the 1950s. Over the past decade, the production technologies are maturing, continuously improve product quality.     First, ERW steel pipe used in the production of raw material quality has been significantly improved, the steel component design of the low C, low P, S, micro-alloying; smelting process smelting, ladle refining, vacuum degassing, continuous casting and other new using technology; ERW pipe - ERW rolling process controlled rolling, controlled cooling technology enables the use of medium and large caliber ERW steel pipes hot strip appearance of size, appearance quality, physical and chemical ...