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Stainless steel plate is usually the floorboard of the stainless steel plate and acid steel plate, since the turn of the century, up to now has 90 years history.Its surface is bright and clean, high plasticity, toughness and mechanical strength, acid and alkaline gas, solution, and other media corrosion.It is a kind of alloy steel is not easy to rust, but not absolutely not rust.Stainless steel plate is weak media such as air, steam and water corrosion resistance of steel, acid steel plate is refers to the chemical etching media such as acid, alkali, salt corrosion of the steel plate.Stainless steel plate has high temperature oxidation resistance, however, oxidation rate would be exposed to the environment and the influence of natural factors such as product form.

With thin oxide film on the surface of the stainless steel slab and density, not easy to fall off, usually state of stainless steel slab in reheating furnace can produce 0.2 ~ 0.3 mm scale, within the scope of the casting defects with the oxidation of iron removal, if the defect is beyond the scope of this, on the slab surface defects such as processing, is bound into the final product.Stainless steel slab is not usually adopt scarfing slab surface defect, will cause the slab flame cleaning area of the composition and phase composition change, affect the corrosion resistance of stainless steel products.Therefore, the mechanical cleaning is a common effective means of stainless steel surface treatment.General way has a tin oxide cleaning machine processing, water blasting, shot blasting machine clean.1 machine processing tin oxide, tin oxide cleaning machine is mainly composed of steel brush roller, drive, clamping device of high pressure water system, cooling water system and etc.Two with steel wire roller (called steel brush roller) installed on the roller table seat, steel brush roll along the slab running in the opposite direction of high speed rotation, using steel wire on the surface of slab washed to remove attached to the iron oxide on the surface of the slab.Tin oxide cleaning machine for steel is more, but the iron oxide cleaning thoroughly enough.2, water pool water pool in normal temperature circulating water as cooling medium, the high temperature slab in the pool, use "water blasting" remove iron oxide on the surface of the slab.Its principle is when the water in high temperature slab instant vaporization, water burst, produced a large number of high pressure steam, the steam of impact force for slab surface oxide flake.At the same time, iron oxide on the surface of the slab and under high temperature condition in water cooling contraction stress, sharply due to produce stress between iron oxide on the surface of the slab and its size is different, tin oxide fracture and fall off.Water pool low investment, less maintenance, low production costs.But for steel is less, only apply to the part of the austenitic stainless steel, steel grade, such as 301, 304.3 clean shot blasting machine, shot blasting machine used to clean up the slab surface oxidation iron.Shot blasting machine is mainly composed of chamber blasting, polishing head, blasting conveying system, shot blasting cleaning device, pellet material filling, dust removal system, lubricating system and electrical control system, etc.Its working principle is the use of shot blasting machine of high speed steel shot blasting shock slab surface oxidation iron, make its loss.Shot blasting machine operation efficiency is higher, the cleaning speed can be up to 3 m/min.Applicable to steel grade.Tin oxide removal effect is good.Just shot blasting machine can't handle high temperature slab, slab temperature below 80 ° general requirements, so the shot blasting machine clean casting iron oxide can't online operation, the slab must be cooled to below 80 ° and blasting operations.

Stainless steel after welding, must carry on the post-processing, such as cleaning, protection, anti-oxidation and so on.(a) cleaning, after the welding bead of scale, there will be a black yellow and blue to his clean, say that clear brand welding spot cleaning cream can remove the oxide skin, also can have the effect of passivation, and can keep the stainless steel color.(2) protection, is formed in the surface of a transparent layer of epidural, can isolate air and water pollution to the stainless steel corrosion, etc, say that clear brand also contains rust material in the coating liquid, can effectively prevent the rust of the metal and have prominent slow-release effect.After treated with this product of beautification, protection on its surface form a very thin and transparent hard film, this film has no hands.Dust from the function of the secondary pollution, it doesn't affect metal texture and color, and highlight the anti-rust and difference.

The idea of duplex stainless steel dates back to the 1920s with the first being cast in Avesta in Sweden in 1930. However, only in the past 30 years duplex steel has begun to "take off" in a remarkable way. This is mainly due to advances in steelmaking technology, especially for nitrogen content control. Standard austenitic steels like 304 (1.4301) and ferritic steel 430 are also relatively easy to manufacture and manufacture. As the name implies, they consist of a single stage, austenite or ferrite. While these types are thinner than a wide range of applications, there are two types of weaknesses in some important techniques: Austenite - low strength (0.2 MPa at 200 MPa in solution annealed condition), low resistance stress corrosion cracking Ferrite - low strength (slightly higher than austenitic, 250 MPa 0.2% PS), poor in the thick part of the weldability, poor low temperature toughness In addition, the high nickel content of the austenitic type causes price volatility which is undesirable for many end users. The basic idea of duplexes is to produce a chemical composition that results in a roughly equal mixture of ferrite and austenite. This phase of the balance provides the following: Higher strength - the current duplex for 0.2% PS is 400-550 MPa. This may result in a reduction in the thickness of the portion, and therefore, a reduction in weight. This advantage is particularly significant for applications such as: Pressure vessels and storage tanks Ø Structural applications such as bridges Weldability of the thick part - not so simple, because the austenitic stainless steel, but ferritic stainless steel is much better. Good toughness - better than low temperature ferritic stainless steels, and better usually down to minus 50 degrees Celsius, stretching to minus 80 degrees Celsius. Resistance to stress corrosion cracking - Standard austenitic steels are particularly susceptible to this type of corrosion. What kind of application, this advantage is very important include: O hot water tank Ø brew cans O process plant Ø Swimming pool structure How the Austenite/Ferrite Balance is Achieved To understand how duplex steels work, first compare the composition of two familiar steels austenitic 304 (1.4301) and ferritic 430 (1.4016). Structure Grade EN Number C Si Mn P S N Cr Ni Mo Ferritic 430 1.4016 0.08 1.00 1.00 0.040 0.015 - 16.0/18.0 - - Austenitic 304 1.4301 0.07 1.00 2.00 0.045 0.015 0.11 17.5/19.5 8.0/10.5 -

Stainless steel products according to user requirements and the complexity of the situation is different respectively by mechanical polishing, chemical polishing, electrochemical polishing and other methods to achieve the mirror Dan Guangze. Mechanical polishing, good leveling, high labor intensity light, pollution is serious, difficult to machine complex parts, reduced gloss, high investment costs and simple parts, medium and small products, complex parts can not be processed. Light Zeda less than the entire product consistency, gloss retention time is not long. Chemical polishing less investment, complex parts can throwing, high efficiency, speed and brightness is insufficient, the polishing liquid to humidification, gas spill, need appropriate wind equipment. Complex products, brightness less demanding products can be used relatively cost-effective small batch processing. Electrochemical polishing of specular gloss, long-term, process stability, less pollution, low cost, pollution prevention is good. One-time investment, complex parts to be installed tooling, auxiliary electrode, mass production to cool dirt block products, requires a long time to keep the mirror light, bright products. Process is stable, easy to operate, can be widely used. Here to talk about the method: 1. ion deposition or oxide method, the workpiece is placed in a stainless steel vacuum coating machine for vacuum evaporation plating: for example: titanium gold watch case and watch band. Usually gold. This method is suitable for high-volume processing. Because large investment, high cost, low-volume products uneconomical. 2. The high temperature oxidation in particular molten salts, immersed in the work to maintain a certain range of technology, so that the workpiece to form a certain thickness of the oxide film, while showing a variety of different color. 3. The chemical method is a specific solution to form a color film by chemical oxidation, generally have "due to Law" use more, but to be able to ensure consistent color batch of products, it must be controlled by reference telegram. (4) electrochemical method, in particular a solution, the color of the film is formed by electrochemical oxidation, this business has been applied. 4. Gas lysis method, is more complex, rarely used in industry.

Food grade stainless steel and 304 stainless steel distinction When heavy metal stainless steel products in use exceeds the limit migration, there is a potential health hazard. Thus, the production of stainless steel cookware, you need between the corrosion protection and security to find a balance. If nickel, chromium content, corrosion enhancements, but the attendant nickel, chromium precipitation will also increase the amount of increase means that the security risk. Because of this, "Stainless Steel" (GB9684-2011) national food safety standards, cooker chromium, cadmium, nickel, lead and heavy metals precipitation amount index has strict provisions. Why does not specify the national standard manganese migration limit (most countries internationally unspecified)? One reason is that, with the increase in stainless steel manganese content, accompanied by a cooker corrosion, rust and other damage to its function, once the manganese content to a high value, such products may not be used or can not be called stainless steel cookware cookware a. But even such a high manganese content, generally do not have health effects. Therefore, the national food safety standards, although not make provision for manganese content, but made clear that the main part of the food containers, made of stainless steel must be selected in line with national standards. Food grade stainless steel tube that is in line with GB9684 standard stainless steel. 304 stainless steel is a very common, the industry also known as 18/8 stainless steel. Its corrosion resistance is better than 430 stainless iron, corrosion-resistant, high temperature, good processing performance, it is widely used in industrial and medical furniture industry and the food industry, for example: Some high-grade stainless steel tableware, kitchen utensils bathroom. 304 is a versatile stainless steel, it is widely used to produce good overall performance (corrosion resistance and formability) of equipment and parts. To maintain the inherent corrosion resistance of stainless steel, the steel must contain more than 17% of chromium, more than 8% of the nickel content. Usually food grade 304 stainless steel is not a special processed food grade.

Stainless steel rod material, chemical composition, application, quality management presentation material: 304,304L, 321,316,316L, 310S, 630,1Cr13,2Cr13,3Cr13,1Cr17Ni2, duplex steel, antibacterial steel and other materials! Applications: petroleum, electronics, chemical, pharmaceutical, textile, food, machinery, construction, nuclear power, aerospace, military and other industry quality management:! ISO9001: 2000 quality management system certification, and production licenses! Note: You can build all kinds of non-standard materials, specifications of stainless steel bar. 303 is cutting stainless steel respectively containing sulfur and selenium, the main requirements for cutting and surface Guanghao high occasions. 303 stainless steel to improve machinability and high temperature bonding properties. Ideal for automatic lathes. Bolts and nuts. 303 austenitic stainless steel is wear-resistant cutting stainless steel acid, in order to improve the performance of the steel, may be added in the steel more than 0.60% molybdenum, is resistant to erosion, product good cutting resistance and burn. corrosion resistance. 303 stainless steel mechanical properties after annealing to stress, tensile strength 515MPa, yield 205MPa, elongation of 40%. 303 stainless steel standard hardness HRB 90-100, HRC 20-25, Note: HRB100 = HRC20 Chemical Composition (%): C: ≤0.15 Si: ≤1.00 Mn: ≤2.00 P: ≤0.20 S: ≥0.15 Cr: 17.00- 19.00 Ni: 8.00-10.00 components can be divided according to Cr (SUS400), Cr-Ni system (SUS300), Cr-Mn-Ni (SUS200) and precipitation hardening systems (SUS600). 200 Series - chromium - nickel - manganese austenitic stainless steel 300 Series - chromium - nickel austenitic stainless steel 301 - scalability for molding products. It can also be hardened by the machine speed. Good weldability. Abrasion resistance and fatigue strength than 304 stainless steel. 302 304 with corrosion resistance, due to relatively high carbon intensity and therefore better. 303 - by adding a small amount of sulfur and phosphorus to more than cutting processing. 304- that is 18/8 stainless steel. GB grades for 0Cr18Ni9. 309 - 304 - better temperature resistance. 316 - After 304, the second most widely used of steel, mainly for the food industry and surgical equipment, add molybdenum to obtain a special corrosion-resistant structure. Than the 304 because it has better resistance to chloride corrosion and thus as "marine steel" to use. SS316 is often used to fuel recovery. 18/10 grade stainless steel is usually in line with the application level. [1] Model 321 - not only because titanium elements to reduce the corrosion of the weld performance than the risk of material similar to 304. 400 Series - ferritic and martensitic stainless steel 408 - heat resistance, corrosion resistance is weak, 11% Cr, 8% of Ni. 409 - the cheapest model (BAR), commonly used as automobile exhaust pipe, is a ferritic stainless steel (chrome steel). 410 - martensite (high strength chrome steel), good wear resistance, corrosion resistance is poor. 416 - added sulfur to improve the processing performance of materials. 420 - "Cutting Class" martensitic steel, similar to Brandt's first high-chromium stainless steel this. Also used in surgical tools, you can do very light. 430 ferritic stainless steel, decorative, such as for car accessories. Good shape, but heat resistance and corrosion resistance worse. 440 - high strength cutting tool steel, carbon slightly higher, after appropriate heat treatment to obtain a higher yield strength and hardness up to 58HRC, are among the most hard stainless steel. The most common application example is the "razor blades." There are three common models: 440A, 440B, 440C, in addition to 440F (easy processing). 500 series - resistant chromium alloy steel. 600 Series - martensitic precipitation hardening stainless steel. 630 - The most common type of precipitation hardening stainless steel models, often called 17-4; 17% Cr, 4% Ni.

Concrete Stainless Steel U Channel section in addition to a good flow, flow, flow speed, anti-leakage, easy to deposit sand and other characteristics, but also has the following significant advantages: 1 seepage effect is remarkable. Water efficiency of small concrete U-shaped groove can reach 0.97 to 0.98, due to the concrete "U-groove" than concrete trapezoidal (or for Masonry) channels wet week short, fast flow, less cracks, and therefore water loss than trapezoidal canal small. 2 hydraulic conditions, and flow speed. The lower part of the Stainless Steel U Channel semicircular curve, in line with the natural characteristics of the water, the approximate best hydraulic cross section. Velocity distribution is uniform, no vortex reflux phenomenon, wet short weeks, the hydraulic radius is large. 3 Good resistance to external performance. Concrete U-shaped groove of the lower part of the soil semicircular grooves in a steady state, the upper side of the soil line segment less pressure, the lower part of the anti-concrete masonry arch, overall good. In soil external force, able to adapt to the overall elevation, can take full advantage of concrete good compression performance, which was less than the trapezoidal crack failure. 4 lining canals footprint. Outfall narrow concrete U-shaped groove, channel covers only trapezoidal channels 1/2 ~ 1/4, and the greater the flow, the relative trapezoidal channels, the more saving land. 5 Lining Construction provincial labor and materials. Wet concrete Stainless Steel U Channel short weeks, a relatively small amount of lining material, less investment, material saving 25% to 30% than the average concrete trapezoidal channel. 6 to facilitate maintenance and management. Workload concrete U-shaped groove lining canals embankment refurbishment, maintenance Repairing cracks and other channels greatly reduced, saving maintenance and management of the labor force 60% to 70% over the trapezoidal channels. 7 good quality, high strength, permanent good. Prefabricated pouring process using the first plane bending vibration and then a new molding process, the vibration effect, at the time of the U-shaped bend at the bottom of the groove and produce local extrusion, again raised the solidity and produce a pre-stress, and increased bottom thickness. 8 investment, high efficiency, easy security puzzle. Jiangchuan by Xinping counties and a number of projects to promote the use of U-groove data show, with U-shaped groove lining canals, than traditional cast-stone or wool lining saving investment.

Many in the processing of stainless steel wire products, there will be glitches, burrs, sharp edges, rough surface, matte and other issues. How to efficiently deal with these problems? Electrolytic deburring: Use electrolysis An electrolytic machining method of removing the metal burr, the English abbreviation ECD. The tool of the cathode (usually brass) have a fixed place in the vicinity of the work site burr, both located a gap (generally 0.3 to 1 mm). Tool of the cathode conductive portion aligned with burr edge, covering up other surfaces with an insulating layer, so that electrolysis concentrated in burr section. Machining tool cathode to the negative DC power supply, the workpiece then positive DC power supply. A pressure of 0.1 to 0.3 MPa low pressure electrolyte solution (typically an aqueous solution of sodium chlorate or sodium nitrate) flowing between the workpiece and the cathode. When connected to a DC power supply, will produce burrs are removed by anodic dissolution, was taken away by the electrolyte. There are certain corrosive electrolyte, the workpiece should be cleaned deburring and rust treatment. Electrolytic deburring suitable for removing parts of the hidden parts of the cross-hole burrs or shape complex parts, high production efficiency, deburring time is usually just a few seconds to tens of seconds. This method is commonly used in gears, splines, connecting rod, crankshaft and valve orifice oil deburring, etc., as well as rounded corners and so on. The disadvantage is near the burr also been electrolysis, the surface will lose their luster, and even affect the dimensional accuracy of stainless steel wire. Chemical deburring: Electrochemical reaction principle, the metal material parts automatically and selectively complete deburring job. It can be widely used for deburring pneumatic, hydraulic, mechanical engineering, pump nozzle, cars, engines and other metal materials in different industries pump, valve, connecting rod, piston and other parts of the needle Couples. Suitable for difficult to remove internal burrs, heat treatment and finishing parts. Hand deburring: The traditional way is steel file, sandpaper, grinding polishing; and trimming knife gradually replaced these traditional methods, easy to use, does not require technical processing, cost savings and environmental protection. Ultrasonic deburring: When the ultrasonic energy generated in the liquid in the ultrasonic vibrations in a liquid state is sparse, it will tear into a small hole (that is, the interior is a vacuum) in these holes occur when broken up to several hundred atmospheres of pressure the moment , and this phenomenon is called cavitation both. Ultrasonic deburring is to use an instant impact "cavitation" generated hundreds of atmospheric pressure to adhere to the member burrs removed. Ultrasonic deburring all burrs are not applicable, Chun-Stainless Steel think this method focuses on some of the microscopic burrs, generally if burrs need a microscope to observe, then you can try to remove by ultrasonic method. For visible glitches, mainly to see the strength of the bond, the bond strength is weak glitches can use an ultrasound, if the general burrs with a cutter to process, with the ultrasonic method is simply not acceptable.

Using 304 stainless steel measuring liquid, we can easily see through some of the fraud on the market and inferior 304 stainless steel tube true to some extent. For example, buy 304 grade 304 stainless steel, we can provide for manufacturers "304" products for testing. 304 is really the case, we used the above-mentioned '304 type "measurement liquid or" Ni8 "type assays were tested, it should be a corresponding test results, otherwise, it is not really 304; if then" low of Ni "determination was further tested purple beads drug discovery, it indicates that the product is a kind of high manganese steel, is also likely to be prevalent in the current market, the corrosion resistance of low and inferior 304 stainless steel, the so-called "200 series 304 stainless steel pipe" . When using 304 stainless steel tube measuring roughly Determination of specific elements about the test liquid identification, referencing and asked us to learn more about the national standard 304 stainless steel chemical composition requirements. In addition, the quality 304 stainless steel tube material is not just the level of the chemical composition of its decisions, but also in its organization, performance, purity and other factors. For the determination of these factors, 304 stainless steel tube test liquid is obviously powerless, only by means of the relevant professional test test. Currently on the market 304 stainless steel tube measuring liquid products, there is not enough scientific place in the logo. As mentioned above with "N" instead of "Ni" case, there will be 200 series 304 stainless steel tube is divided into "200,201,202" and so on. In actual use of the process also found that some test results is difficult to distinguish with the naked eye, prone to error. As the test in addition to the more obvious color difference between 201,202 and 301,304, but between 201 and 202, 301 and 304 between the color change is not very obvious. These unscientific and deficiencies of the manufacturers concerned need to be further improved.

Common relevant national standard Stainless Steel Plate thickness tolerance comparison Strip thickness tolerance 1, China National Standard (GB) Unit: mm width thickness Thickness tolerance High precision(A) General accuracy(B) >600~1000 >1000~1250 >600~1250 0.05~0.10 ---- ---- ---- >0.10~0.15 ---- ---- ---- >0.15~0.25 ---- ---- ---- >0.25~0.45 ±0.040 ±0.040 ±0.040 >0.45~0.65 ±0.040 ±0.040 ±0.050 >0.65~0.90 ±0.050 ±0.050 ±0.060 >0.90~1.20 ±0.050 ±0.060 ±0.080 >1.20~1.50 ±0.060 ±0.070 ±0.110 >1.50~1.80 ±0.070 ±0.080 ±0.120 >1.80~2.00 ±0.090 ±0.100 ±0.130 >2.00~2.30 ±0.100 ±0.110 ±0.140 >2.30~2.50 ±0.100 ±0.110 ±0.140 >2.50~3.10 ±0.110 ±0.120 ±0.160 >3.10~<4.00 ±0.120 ±0.130 ±0.180 2, the Japanese Industrial Standard thickness width <1250 ≥1250~<1600 ≥0.30~<0.60 ±0.05 ±0.06 ≥0.60~<0.80 ±0.07 ±0.09 ≥0.80~<1.00 ±0.09 ±0.10 ≥1.00~<1.25 ±0.10 ±0.12 ≥1.25~<1.60 ±0.12 ±0.15 ≥1.60~<2.00 ±0.15 ±0.17 ≥2.00~<2.50 ±0.17 ±0.20 ≥2.50~<3.15 ±0.22 ±0.25 ≥3.15~<4.00 ±0.25 ±0.30 ≥4.00~<5.00 ±0.35 ±0.40 ≥5.00~<6.00 ±0.40 ±0.45 ≥6.00~<7.00 ±0.50 ±0.50 3, American Standard Materials Association (ASTM) standards thickness Tolerance width up down ≤1000 >1000~≤1300 0.10 0.03 0.03 0.15 0.04 0.04 0.20 0.05 0.05 0.25 0.05 0.05 0.30 0.03 --- 0.40 0.04 0.04 0.50 0.08 0.08 0.50 0.045 0.05 0.60 0.05 0.05 0.75 0.10 0.10 0.80 0.05 0.05 1.00 0.13 0.13 1.00 0.055 0.06 1.20 0.08 0.08 1.25 0.13 0.13 1.50 0.08 0.08 1.75 0.15 0.15 2.00 0.18 0.18 2.00 0.10 0.10 2.25 0.20 0.20 2.50 0.23 0.23 2.50 0.10 0.11 2.75 0.25 0.25 3.00 0.25 0.25 3.00 0.13 0.13 3.25 0.30 0.30 3.50 0.30 0.30 3.75 0.36 0.36 4.00 0.36 0.36 4.00 0.17 0.17 4.99 0.36 0.36 5.00 0.17 0.17 6.00 0.17 0.20 8.00 0.17 0.22

Common stainless steel model common numeric notation, 200 series, 300 series, 400 series, which are the US representation, such as 201,202,302,303,304,316,410,420,430, etc., is the American Iron and Steel Institute with three digits to mark a variety of standard grade wrought stainless steel. Differences in functionality: 304 is a versatile widely used stainless steel, it is widely used to produce good overall performance (corrosion resistance and formability) of equipment and parts. In buildings can withstand general corrosion, resistant to food processing etching medium (but high temperature concentrated acid and chloride containing components possible corrosion), organic compounds, dyes and wide variety of inorganic compounds can resist. Type 304L (low carbon), and good resistance to nitric acid, and durable medium temperature and concentration of sulfuric acid, widely used as a liquid gas tank, used for cryogenic equipment (304N), other consumer goods and appliances, kitchen equipment, hospital equipment, transport tools, waste water treatment apparatus. 430 lower than the 304 alloy content, used as a mild atmosphere highly polished decorative purposes, it can also be used nitric acid and food processing equipment. difference of 201 and 304 stainless steel : 1, Specifications: conventional stainless steel sheet is divided into two models 201 and 304, actually is a component differ, 304 good quality, but the price is expensive, 201 worse. 304 imported Stainless Steel Plate, 201 domestic stainless steel plate. 2, 201 composition of 17Cr-4.5Ni-6Mn-N, the section Ni steel, replace steel 301 steel. After cold working with magnetic, for railway vehicles. 3, 304 composed of 18Cr-9Ni, is the most widely used stainless steel, heat-resistant steel. For food production equipment, past through chemical equipment, nuclear energy. 4, 201 is a high manganese, the surface is very dark with a bright light, high manganese easily rust. 304 chromium containing more matte surface rendering, does not rust. We have put together a comparison of two kinds. The most important thing is different corrosion resistance, corrosion resistance 201 can be poor, so the price will be much cheaper. And because 201 nickel-containing low, the price is lower than 304, so the corrosion resistance as good as the 304. 5, the difference is nickel issues between 201 and 304. And the price is 304 now are more expensive, are generally required to be close to 50,000 a ton, but then at least you can guarantee 304 during use will not rust. (Syrup available to do the experiment) 6, stainless steel because rust is formed on the surface chromium-rich oxide protects the steel body, 201 is a high-manganese steel material hardness of more than 304 high-carbon low nickel.

840 (S33400) is a kind of containing titanium and aluminum alloy austenitic stainless steel, chromium containing enough to form and maintain a sufficient size of chromium oxide, make its are protected under the condition of high temperature, than conventional chromium nickel stainless steel such as 304 more resistant to high temperature;High nickel content, compared to the standard of 18-8 stainless has better oxidation resistance and the oxidation resistance as temperature up to 1900 degrees f (1038 ℃), the higher grades of alloy.Therefore, 840 (S33400) alloy is manufacturing, automotive emission control system and other electric heating tube of high temperature resistant products ideal material. Stainless steel grade 334 can be applied in these areas: because of its formability, weldability and corrosion resistance and oxidation resistance of 840 alloy is a kind of common materials, electric heating tube used in the manufacture of electric heating tube, heat exchangers, heater equipment, industrial furnace and other equipment, also commonly used in automobile exhaust system.

Stainless steel is less contains fifty seven 50% iron and 10.5% chromium, and also to join such as nickel, titanium, molybdenum, according to different containing suspension components, the metal internal microstructure is different also, it is markov shape, iron grain size, austenite, duplex, precipitation hardening stainless steel, etc.Health level of seamless stainless steel pipe has a different material. General industrial tube austenite size stainless steel material is more commonly used;00 0 cr19ni9 (USU304), cr19ni11 (USU 304 l), 0 cr17ni12mo2 (USU) 316, 00 cr17ni14mo2 (USU 316 l), 1 cr18ni9ti (SUS 321), etc.In accordance with GB/T14976-94 the standard of the journal fluid conveying stainless steel seamless steel tube, and the requirement of steel pipe inside and outside surface finish. Health level of choose and buy seamless stainless steel pipe and fluid type, concentration, temperature, pressure, flow rate, and other factors.

Stainless steel is not easy to rust steel, in fact, part of stainless steel, have both stainless, and acid resistance, corrosion resistance).Stainless steel does not rust and corrosion resistance is due to its rich chromium oxide film on the surface (passivation film).This is not to rust and corrosion resistance is relative.Experiment shows that the steel in the atmosphere, the weak medium such as water and nitric acid oxidation, such as medium, its corrosion resistance increased with the increase of the water content of chromium in steel, when the chromium content reaches a certain percentage of steel corrosion resistance mutation, that is, from easy to rust is not easy to rust, never corrosion resistant to corrosion. China's private stainless steel enterprises occupy the important position in the market, private stainless steel enterprise development present situation as follows: 1. Private steel mills has expanded rapidly, the production capacity, status enhances unceasingly. The birth of private stainless steel enterprises solve the civil steel grade stainless steel aspects from scratch, from there to the good problem;China's private stainless steel enterprises laid a solid foundation for the development of Chinese stainless steel industry.Capacity increase rapidly.Now private stainless steel enterprises factory capacity accounts for the total capacity of up to 60%. 2. Private steel plant layout regionalization, industry layout rationalization. According to the coast, along the Yangtze river, inland scientific and rational layout and corresponds to the resources and environment requirements, move backward, corporate restructuring and urban steel plant, in the national standard and revitalization of the steel industry and the revitalization of the planning, under the premise of total control, adjusting and optimizing industrial layout, industrial layout is obviously improved, but most of the steel mills are still concentrated in jiangsu and zhejiang, guangdong, fujian and other coastal provinces.From the industry layout of southwest, henan jin hui, stainless steel wide green science and technology, the north sea, fujian ding letter is all stainless steel enterprise unique large private enterprises, is also the leader of the local industrial enterprise, whether it is the support of local protectionism, or the need of industry planning, they will still exist and rational development for a long time. 3.Product varieties, specifications and diverse, the main products of the private steel mills transition from narrow to wide plate. Mainstream private stainless steel enterprise scale enterprises, after many years of market segmentation, stainless steel materials are: stainless steel belt, stainless steel rods, stainless steel plate, stainless steel wire, stainless steel pipe;The current mainstream products involving steel in 201 hot strip copper, 201 hot strip high copper, 304 hot strip is given priority to;202 hot strip, 301 hot strip hot rolling belt, D7, D11 hot strip for supplementary form a private steel mills products system;The thickness of the product specification is 2.0 mm to 5.0 mm as the main body;Products range from 300 mm to 1520 mm width, mainstream - 620 - mm to 380 mm as the main body of the specifications of the sales. 4.New production technology constantly, "stainless steel nickel iron" is a new industry. In addition to perfecting and upgrading existing hot rolling equipment, private small smelters in smelting practice equipment also constant self-improvement, to explore more of the upstream industry chain is perfect, is committed to lower production costs, production process innovation.RKEF technology is a kind of technology nowadays is more fashionable.Now about eight domestic enterprises have the technology, the basic distribution in coastal areas, the process of nickel iron accounted for about 20 to 30 of the nickel pig iron production 20-30% annual output can reach 80000 tons of nickel.Jiangsu taizhou cavey stainless steel products co., LTD. Use RKEF process from nickel iron to stainless steel continuous casting and rolling process of integration model, and was a great success, and has set an example for other enterprises.In 2013 and 2014 will be a new start RKEF nickel iron works of dense phase, which since 2013, the domestic construction and proposed RKEF craft project nickel iron production capacity of 320000 tons, five companies of 140000 tons of production capacity will be put into production this year, including four companies take the industry pattern of "stainless steel nickel iron", in 2014 there were 2 companies a total of 80000 tons of nickel iron RKEF process project put into production, also copy "nickel iron stainless steel" integration business model.In a single nickel iron as, China's nickel iron enterprises are exploring and practice "nickel iron stainless steel" business model, also become an important direction of earnings in the next few years. 5. Constantly improve the resources utilization ratio, markedly enhance its capability of sustainable development. Mainstream private hot rolled stainless steel enterprises to realize the basic guarantee in 88%, more enterprises can maintain in 93% the right of hot rolling yield.Scale enterprise after complete environmental protection technical renovation, even if the practice of smelting slag is further recycled steel, to a great extent on the stainless steel scrap consumption also has a strong ability, social fully recycle waste resources, saving our country important metallurgical resources are relatively scarce of nickel, chromium. 6. Flexible sales model is not a single, trade. Only meet the domestic demand and exports this year also has a substantial increase.The signs (MEPS) release, global stainless steel production in 2016 will grow 2% right, production reached a record high of 42.3 million tons.After the fight, global stainless steel production in 2015 is expected to less than 41.5 million tons. Signs of prediction, 2015 years of Chinese stainless steel production from 2014, a slight drop in output, the output of 2016 year-on-year growth of 1.7% modest right;2015 stainless steel production in Japan is likely to more than 3 million tons, is expected in 2016 stainless steel production in Japan will be compared to the same growth 5%.Although South Korea's stainless steel output strong year-on-year growth in 2015 was 9% the right, to fight, is expected in 2016, South Korea's stainless steel output could not continue to increase;A slight drop in production of stainless steel 2015 China Taiwan, expects its 2016 stainless steel production in 2015 will be a slight increase of 2.7% right;Although the production of stainless steel stainless steel production enterprises in the United States in 2015 from a year before the down slightly, but in 2016 is expected to moderate back to about 2.4 million tons.The signs, the stainless steel production in 2016, the eu is expected to rebound to the level of 7.25 million tons in 2014.