• Right Way to Save Spiral Pipe

    Proper way to preserve spiral pipe 1) Storage space spiral steel pipe products or warehouse, should be selected in clean, smooth drainage area, away from harmful gases or dust in factories and mines. The presence on the ground to clear the weeds and all the debris, keeping a clean steel 2) In a warehouse not with acid, alkali, salt, cement, steel and other aggressive materials stacked together. Different varieties of steel should be stacked separately, to prevent confusion, to prevent contact corrosion 3) Large steel, rail, steel disgrace, large diameter steel pipe, forgings, etc., may open dumps 4) Small and medium steel, wire rod, rebar, medium diameter steel pipe, steel wire and wire rope, etc., can be expected in a well-ventilated storage shed, but it must be the underlying thatch 5) Some small steel, sheet, strip, silicon, or thin-walled small-diameter steel pipes, all kinds of cold-rolled, cold-drawn steel products and high prices, corrosive metal products, can be stored for storage 6) A warehouse should be based on selected geographical conditions, the general ordinary enclosed warehouse, that is the roof with walls, doors and windows tight, with the Treasury ventilation device 7) Requires the Treasury sunny attention to ventilation, rain close attention to moisture, keep the appropriate storage environment
  • Difference between ERW Steel Pipe and UOE Steel Pipe

    First, the raw materials and production capacity difference ERW steel pipe material is hot-rolled coil, UOE steel pipe material is hot-rolled steel. Therefore, ERW steel pipe can achieve a continuous pipeline operations, high production efficiency, low production costs; and UOE steel pipe is used to process, it can not achieve a continuous pipeline operations, low productivity, high production costs. Restricted ERW steel pipe coil thickness, the maximum thickness can be produced for 25mm, to produce a maximum diameter of 660mm; the maximum thickness of the UOE steel pipe can be produced as 40mm, produces the largest diameter is only limited by the width of the sheet, the current can be produce the maximum diameter of 1422mm. Second, the difference between welding ERW pipe welding without additional wire; UOE steel pipes need to add the wire. Third, the appearance difference ERW steel inside and outside welds required to be removed, so the antiseptic beneficial; UOE Pipe Wall Weld stay more than a high anti-corrosion disadvantage. Fourth, the difference between the purchase cost and the difficulty  ERW steel procurement costs low, UOE steel pipe cost is very high, generally spread is 15% -25%. Domestic UOE steel pipe manufacturers less purchasing high degree of difficulty. When the diameter <Φ406mm, the greater the difference between the purchase cost. ERW steel pipe manufacturers are more low purchasing difficulty, when the diameter of
  • Advantages and Disadvantages of Electric Resistance Welding

    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 flash butt welding sparks splash, need to be isolated. Shortcoming of electric resistance welding 1, there is a lack of reliable non-destructive testing methods, the quality of the welding process can only rely on destructive test specimens and artifacts to examine and rely on a variety of monitoring techniques to ensure that. 2, point seam welding lap joint not only increases the weight of the structure, and because the two plates nugget formed around an angle, so that the tensile strength and fatigue strength of the joint were low. 3, power equipment, high mechanization and automation, so that the higher cost of equipment, maintenance more difficult, and the commonly used high-power single-phase AC welder is not conducive to balanced operation of the grid.
  • Disadvantages of Hot Rolled Steel

    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.
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