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Ordinary life is often applied to a 304 stainless steel angle bar iron rust appears, someone that would be impossible, but the stainless steel. In fact, this is a mistake a lot of people will think stainless steel is unlikely to rust, in fact, it is just not easy to rust,304 stainless steel angle bar also will rust. Below about 304 stainless steel angle bar at how to prevent their rusting water vapor. Pure water vapor is unlikely to rust more than 304 steel corrosion caused by rust, if water vapor which is doped with an acidic or alkaline substance it may lead to rust corrosion. If you want to avoid acidic or alkaline substances on the corrosion of stainless steel rust, can be sprayed in a layer of rust-proof material 304 stainless steel angle bar above. Water vapor is impossible absolutely pure no impurities, thus 304 stainless steel angle bar will certainly be rusty, the difference is the possibility of rusting problem sooner or later. If you want to prevent rust coated with a layer of material, the material is likely to be slightly toxic, need more bearable. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

low temperature carbon steel pipe is medium carbon structural steel, cold steel plus low energy are good with good mechanical properties, and low prices, wide sources, so widely used. Its biggest weakness is the low hardenability, cross-sectional dimensions Japan is relatively high workpiece should not be used. Cold steel for low temperature operation, can withstand a certain low temperature impact. Low temperature quench pipe A3 + (30 ~ 50) ℃, in practice, is usually set to the upper limit. High quenching temperature to low temperature pipe heating speed, reduce surface oxidation, and can improve efficiency. The workpiece is uniform austenite, will require sufficient holding time. If the actual installed furnace capacity, would be appropriate to extend the holding time. Otherwise, there may be insufficient due to uneven heating caused by the hardness of the phenomenon. However, the holding time is too long, will also appear coarse grains, oxidation and decarbonization serious ills affecting quenching quality. We believe that such equipment is greater than the specified process documents furnace, the heating need to extend the holding time of 1/5. Because the low temperature steel hardenability is low, it should be large cooling rate of 10% salt solution. After the workpiece into the water, it should hardenability, but not chilled, if in cold salt water penetration, it is possible cracking of the workpiece, it is because when the workpiece is cooled to about 180 ℃, the rapid transformation of austenite horse s body tissue caused by excessive stress due. Therefore, when hardened steel rapid cooling to the low temperature region, it should take slow cooling method. As the water temperature is difficult to grasp, accountable experience to operate, when to stop dithering artifacts in the water, the water can be air-cooled (eg oil cooler can be better). In addition, the work should move into the water should not be static, should be in accordance with the geometry of the workpiece, as the rules of sport. Stationary cooling medium plus stationary workpiece, resulting in uneven hardness, stress uneven leaving large deformation of the workpiece, and even cracking. Cold steel pieces quenched hardness after quenching should reach HRC56 ~ 59, lower section of the possibility of some large, but not less than HRC48, otherwise, it shows the work has not been fully hardened tissues may occur even ferrite sorbitic Organizations, such organizations tempered, still retained in the matrix, which was not quenched purposes. Cryogenic tempering steel after quenching, the heating temperature is usually 560 ~ 600 ℃, hardness is HRC22 ~ 34. Because the goal is to get quenched mechanical properties, so the relatively wide range of hardness. But drawing hardness requirements, it is necessary to adjust by drawing tempering temperature to ensure hardness. For example, some cold steel shafts require high strength, hardness is high; while some gear, shaft parts with keyway, because after quenching but also for milling, insert processing, hardness requirements will be lower. About Tempering time, depending on the hardness and size of the piece, we think, depends on the hardness after tempering tempering temperature, tempering time with little to do, but must return through the general overall at the workpiece Tempering Time more than one hour.

How to extend the life of 316 stainless steel angle bar? People in their daily lives and is closely related to stainless steel, stainless steel angle bar are a lot of people think that will never rust, in fact, good corrosion resistance of stainless steel. The reason is that a passive film formed on the surface, it is a more stable form of oxides exist in nature. But many people recognize the performance of small stainless steel, 316 stainless steel angle bar maintenance will know more and less. That is, by the use of stainless steel, although conditions are different, not the same degree of oxidation, but in the end is oxidized, a phenomenon commonly referred to as corrosion. Exposed to the corrosive environment of the entire metal surface electrochemical reactions occur or the chemical reaction, uniform corrosion. 316 stainless steel angle bar surface passivation film corrosion resistance among the weak parts, due to the self-excited reaction to form pitting reaction of holes, coupled with chloride ions close to the formation of highly corrosive solution, to accelerate the corrosion reaction speed. There are between stainless steel internal corrosion cracking, all of these, the passivation film on the surface of the stainless steel plate occur damaging. Therefore, the stainless steel surface cleaning and maintenance must be carried out regularly in order to maintain its gorgeous surface and prolong life.

304 stainless steel angle bar under what circumstances need to be passivation it? 304 stainless steel angle bar when corrosion occurs, the process is essential, and in the case of passivation is 304 stainless steel angle bar needs to be thrown by the erosion. Passivation treatment method is now mainly: pipe and hand straight and without manifolds can manipulate the stainless steel tube, available passivation paste in the workshop scene. The method is to pipe welding after welding increase in seniors is polished, the residue removal in the weld surface and near oxides, but also its stainless steel qualities, then the average passivation paste with a brush applicator surface to be treated according to timely ambient temperature, determine the passivation time. Since the passivation paste is a strong acid, not only for fear of destroying the nearby construction site, more importantly, to produce water pollution. Other tools accurate method is to use a clean cloth or rag to wipe like passivation paste, and then water erosion. And to scour the edge, edge with a scouring cloth Passivation, Passivation paste until no residue when after reaching the passivation time, do not rinse with water directly, but use a clean cloth to wipe blunt creams, and then water to wash, rinse and to the side to side with a scouring cloth passivation, 304 stainless steel angle bar‘s surface until no residue and passivation paste is reached. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The uneven wall thickness of steel pipe is mainly represented as uneven spirally wall thickness, uneven straight wall thickness and the ends are too thick or too thin, even the grinding technique is one of the important factors. The following are the reasons to cause the uneven wall thickness and corresponding measures. Steel tube wall thickness is not same, may on the cross section and longitudinal tube body wall thickness range phenomenon exists objectively, which is called the uneven wall thickness. To control this heterogeneity, in some steel standard provides a uniform wall thickness to allow indicators, the general requirement does not exceed 80% of the wall thickness tolerances. Ovality of the circular cross section of the steel pipe there is a diameter ranging phenomenon, that there is not necessarily perpendicular to the maximum diameter and the minimum diameter, the maximum diameter and the minimum diameter is the difference between the ellipticity (or roundness). In order to control ovality, and some steel standard provides the allowable ovality index, generally defined as no more than 80% of diameter tolerance. Characterized uneven wall thickness in the same cross-section thickness of the thickest point A, a thinnest point in the steel spiral longitudinal distribution, large or small pitch. Steel head, tail extent than the middle of uneven thickness serious, if steel pipe in the middle of the unevenness in thickness with a nominal wall thickness tolerance within 80%, then the removal of the head, tail portion of uneven thickness remains qualified products; such as pipe middle unevenness in thickness beyond the nominal wall thickness tolerance zone 80%, then the whole pipe as substandard goods, reducing the finished product rate. Such as uneven wall thickness of the steel pipe longitudinal pitch larger part is due to the heating, resulting in a long pass cross-section billet temperature unevenness actions, such as ring bottom uneven pits formed at the material level, the tube and increase the contact surface of the hearth, the heating time is too long, the heating temperature is too high, the tube and the bottom exists between a large number of iron skin, resulting in a cross-section through a long tube temperature uneven perforation capillary to form a larger longitudinal thickness unevenness pitch. If the wall thickness uneven pitch is small, it is piercing units improperly adjusted due to its characteristic spiral motion, pitch size and perforation pitch equal to the capillary outlet.

The difference between double submerged arc welding (dsaw) and high frequency difference(hfw) is mainly manifested in the appearance of the weld appearance, Double submerged arc welding steel pipe in appearance is with a slight indentation strip, mainly in steel interior. Straight seam submerged arc weld pipe is higher than the base material for the neat 1-3mm weld. In appearance frequency steel tube smooth, non-oxide adhesion. In the weld, high-frequency straight seam steel pipe weld high measure to squeeze flow resistance, the jagged serrate irregular weld, this weld is “scratch” before they go out, leaving a flat weld removal of trace. In addition, two-sided submerged arc welding and high frequency difference is also reflected in the production process, the use of different raw materials, different molding process, the welding process is different from different production units, production of different scope. Sided submerged arc welding straight seam steel production process only with JCOE molding process molding process complex, forming efficiency relative to the low-frequency welded pipe, so the manufacturing cost is higher than the high-frequency straight seam welded steel pipe. High-frequency straight seam welded steel pipe (ERW) production process is simple, a single specification. Double-sided submerged arc straight seam steel pipe forming process is JCOE cold forming, features that make the steel at 50mm gradually forming, J, C, O, E represents the image of straight seam steel submerged arc forming process. Frequency straight seam steel pipe forming process for the multi-pass rolls, squeeze both ends of the strip, and finally justified the strip cold molding process, the molding process is characterized by uninterrupted, continuous welding. Submerged arc welding process is characterized by using steel wire electric effect and melt together, as filler welding. Frequency straight seam steel pipe welding process is characterized by the use of high frequency current skin effect rapid warming strip ends in a short time under the action of external forces strip from melting together. Frequency straight pipe production unit for the same lines of uninterrupted production line efficiency, and submerged arc welding straight seam steel pipe has up to 15 intermittent production processes complete unit. Frequency straight seam steel pipe production specifications fewer production thinner.

Different arc welding requires a corresponding arc welder and arc welder welding power source is the core part. SMAW machines: welding power, welding clamp Submerged arc welding machines: welding power supply, control box, trolley, wire feeder Gas welding and plasma welding machines: welding power supply, control box, wire feeder, welding torch, gas, water and so on. Welding arc is supplying power to a device. Arc welding must have the required electrical performance. Arc welding Arc welding is the most widely used welding methods. It includes: manual arc welding, submerged arc welding, MIG welding (argon, C02 gas, helium), melting polar gas tungsten arc (such as argon) arc welding, plasma welding (argon, nitrogen, helium gas, etc.). MMA Manual arc welding is mainly used for steel (carbon steel, alloy steel, stainless steel), manual arc welding equipment is simple, lightweight, flexible operation, can be applied to any short welds and welding position, the workpiece thickness above 1.5mm, small batch welding quality to some extent depends on the level of operation of the welder, labor-intensive, low productivity. SAW Submerged arc welding wire is continuously fed as electrical panels and filler metals. Welding, the welding area covered with a layer of granular flux, flux under the burning arc, the end of the wire and the workpiece material, partial melting of the formed weld. Flux melted slag bath surface covering to protect the weld metal, to prevent air pollution, and improve weld performance, prompting the weld slow cooling. MIG arc welding MIG arc welding commonly CO2 gas shielded arc welding, TIG welding can be a variety of locations, high production efficiency, can be welded carbon steel, alloy steel, stainless steel. Plasma arc welding Plasma arc welding is a non-melting arc welding, it is the use of compression between the electrode and the workpiece arc (transferred arc) to achieve welding. The electrode is typically used tungsten electrode, arc plasma is generated plasma gas can be argon, helium, and an inert gas ejection nozzle weld pool. Welding filler metal may or may not be filled with metal. ERW ERW suitable for mass production, sheet metal welding, welding equipment is expensive, spot welding, seam welding, resistance welding is a welding heat-to-energy method is to work at a certain plate pressure, and the use of current through the workpiece when resistance heat generated between the two workpieces to connect the contact surface melting of the welding method. Resistance welding methods: Spot, seam and projection welding and other types.

304 stainless steel angle bar of common specifications: 304 stainless steel angle bar specification is represented by side and edge thickness dimensions. Stainless steel is mainly pided into equilateral angle bar steel and stainless steel angle bar stainless steel angle bar equilateral categories, which can be pided into equilateral stainless steel angle bar ranging from thick and scalene equilateral unequal thickness two kinds. Current domestic stainless steel angle bar specifications for 2-20, a few centimeters side to the number of number, the same number of stainless steel angle bar often 2-7 different edge thickness. Imports of stainless steel angle bar indicating the actual size and edge thickness on both sides and indicate the relevant standards. General side length 12.5cm above for large stainless steel angle bars, 12.5cm-5cm between medium-sized stainless steel angle bar, side length of 5cm below the angle bar for small stainless steel.  Import and export stainless steel angle bar of orders generally required specifications in use mainly as its corresponding carbon steel structural steel steel. That is in addition to stainless steel angle bar specification number, no specific composition and performance series. Stainless steel angle bar length delivery sub-length, double length are two, made of stainless steel angle bar iron cut to length range of options, depending on size numbers have 3-9m, 4-12m, 4-19m, 6-19m four ranges. Japanese production of stainless steel angle bar length range of options for the 6-15m. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

304 stainless steel angle bar and 304L stainless steel angle bar differences are as follows: <1>, 304L stainless steel angle bar of nickel-containing more than 304 stainless steel angle bar. <2>, and more importantly, 304L stainless steel angle bar is much smaller than the carbon content of 304 stainless steel angle bar. <3>, the 304L stainless steel angle bar iron welded point perhaps local pitting top of other disposal than 304 stainless steel angle bar better. <4>, 304L stainless steel angle bar more resistant to corrosion, 304L stainless steel angle bar carbon-less, 304 stainless steel angle bar is wide used, has excellent corrosion resistance, heat resistance, low temperature strength and mechanical properties; stamping twists and other thermal processing, and no hardening heat treatment appearance. <5>, 304L stainless steel angle bar after welding or eliminate stress, its resistance to intergranular corrosion is excellent; the case without heat treatment, can adhere to the excellent corrosion resistance, the use of temperature -196 ° C-800 ° C. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The issues and defects of ERW pipes are related to raw materials, production methods, process conditions, equipment status and personnel. Product defects that appear in the production process by the above factors and constraints. This product defects can be pided into roughly two categories: one for product defects, that defects production of the product itself exist inconsistent sets of product standards; a class of defects generated during the production process defects, it do not form the product requirements of the standard items, but also an issue of product quality, and its trend of development will inevitably lead to product defects. Therefore, this defect is not allowed in the production process. Process defects  No burr: burr welds. Outer burr is generally better when the watertight test water pressure. But for Ling, bending, flattening test, weld most cracking.  Peach tip: weld at no glitches, and recessed within the wall, forming the tip shape of peaches, try water pressure when water-tight. But bending, flattening test, weld multiple cracking. Within the burr unilateral: watertight seam burr for the side extrusion test water pressure. Bending, flattening test, sometimes cracking.  Burnt: the outer surface of small pits in the weld, welding sparks a lot of splash, the microstructure observed small holes watertight when the test water pressure, bending, flattening test, most will not crack, but the impact on the intensity of use and life expectancy. Weld defects  Opening: straight weld plate edge face melting traces or melting traces without welding, crack two tip along the weld direction, expansion, penetrate the inner surface of the test water pressure, leaking.  Crack: micro-crack crack; the outer surface of the visible appearance of fine lines, the inner surface of intact, no leakage in the test water pressure, but when crushed or cold-formed crack.  Lap welding: two edge dislocation in the welding, scraping, except burrs can still see the obvious one side higher and exceed the wall thickness of the negative deviation. Surface defects  Scratch: the general was the axis of the straight channels and scratches, deeper than the wall thickness of the negative deviation of scrap defects in the weld on both sides of a continuous nail-shaped scratch. Super wall thickness of the negative deviation. Waste big flaw.  Correction hurt: the leveler spiral crushed obviously feel more than the wall thickness of the negative bias of – waste defect.  Pockmarked face: the tube surface successful piece punctate small pits with a diameter of about 1mm.  Warp: the pipe surface warping the separation of the part and the metal substrate into pieces, not continuous, spalling can not afford.

The 304 stainless steel angle bar What are the precautions when cleaning? Care must be taken not to scratch the surface of the phenomenon occurs when cleaning the surface of stainless steel angle bar, and avoid the use of abrasive-containing bleach component washing liquid, steel balls, grinding tools, the washing liquid is removed, at the end of the washing surface to use clean water rinse. Stainless steel angle bar surface dust and dirt easily in addition to objects, with soap, weak detergent or washing with warm water. Trademark stainless steel surface, the film, with warm water, detergent to wash the weak adhesive composition, use of alcohol or an organic solvent (ether, benzene) scrub. Stainless steel surface oil, oil, oil pollution, after using a soft cloth to wipe clean with neutral detergent or ammonia solution or cleaning with special detergents. Stainless steel surface adhesion bleach and various acids, should immediately wash with water and then ammonia solution or neutral aqueous immersion carbonated soda, rinse with warm water or a neutral detergent. Stainless steel surface a rainbow pattern, generally leads to excessive use of detergents or oil, wash with warm water and neutral detergent can be washed away. Stainless steel surface rust caused by dirt, 10% nitric acid or abrasive detergent washing, washing can also be washed with a special medicine. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

304 stainless steel angle bar identification method and the reasons for rust 304 stainless steel angle bar customers often use it to identify the authenticity of the magnet, the magnet does not suck think they believe is true. In fact, this method is to identify the error. In fact, 304 stainless steel angle bar also with magnetic, will rust. Stainless steel is more than 60% of the iron matrix containing a high alloy NI, Mo and other alloying elements, but the biggest feature is the strong corrosion resistance of stainless steel but not definitely not rust. In some coastal areas or areas with serious air pollution, while large chlorine ion content in the air, exposed to the atmosphere in a stainless steel surface may be some rust, the rust is only limited to the surface, it will not erode the internal stainless steel substrate. Many types of stainless steel, most with a magnetic, therefore, not discriminate 304 stainless steel angle bar with a magnet adsorption scientific method Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)