Search Results

Selection of stainless steel and nickel alloys, the first element is choose the correct stainless steel and nickel alloy grades. Stainless steel and nickel alloy that contains many of the standard level, between the level of chemical composition, corrosion resistance, physical properties, mechanical properties,  there is a big difference. For a particular application to select the most appropriate grade, can be obtained with the least cost to you satisfied with the results. In the choice of grade, consider the material properties.  ​ Select a grade to consider the properties include:  Corrosion resistance; anti-sulfur resistance; use of strength, ductility, and environmental temperature; on the processing technology adaptation; on the adaptability of washing procedures; use the stability of performance; strength anti-wear, anti-erosion; anti- sticky corrosive; reflex; magnetic; thermal conductivity; thermal expansion; resistivity; sharpness; hardness; dimensional stability. Corrosion resistance of stainless steel or heat-resistant steel is usually the most important features, but in the application, corrosion resistance, the most difficult assessment. Under natural conditions, and in pure chemical solution, the corrosion resistance is relatively easy to determine. However, localized corrosion, such as: stress corrosion cracking, crevice corrosion, pitting corrosion, intergranular corrosion (present in the HAZ) is much more complex than the general corrosion. Although there is no such localized corrosion on the structural damage to a large area, but may not be expected to result from, or even fatal failure. Therefore, construction and choice of stainless steel in the design must carefully consider these factors. Corrosion may be through the media, alarming increase in minor impurities, the impurities in the media is difficult to predict, but even if it is the concentration of parts per million can cause serious consequences. In the case of warming, although minor changes in the atmosphere will greatly accelerate the corrosion of metals, may affect the corrosion rate, curing and carburization. Despite these complexities exist, we can combine the steel manufacturer’s recommendations to select the appropriate rule of thumb for most applications of steel. However, to understand one thing: the material obtained by the corrosion test data for predicting performance of a particular kind of deviation from time to time. Even the work the data have been limited because of corrosion similar to some of these media may be due to slight changes in the erosion factors have substantial differences. For demanding applications that require extensive data for these two studies, comparative analysis, and sometimes will follow the lead testing or operation test. The mechanical properties of the working temperature is the primary consideration, but sometimes overlook other temperature requirements to achieve a satisfactory performance. Therefore, the products used for low temperature below zero must have for the performance of the work, although a constant operating temperature may be much higher, at room temperature in work performance are also important. The choice of products not only need to consider the needs of performance, but also consider the handling of processing andcleaning needs. Can be processed with a particular characteristic (easy to shape or weldability) of the material would normally be used, not the other, but that relatively good performance of the high cost of materials processing. Even the cleaning process will also affect the choice of steel. Sometimes, even if the working conditions in the degree of sensitization is not important, but need to be adopted by the welding process of the stable carbon materials that may be ignored. The welding process of the material needs to be placed in a washing medium, such as nitric acid – hydrofluoric acid, sensitized by the media will corrode stainless steel or nickel alloy. For some specialized applications, other properties listed in the list is critical. but in many other applications are rarely considered. Surface finish are important for many applications, sometimes using stainless steel, because it has a beautiful surface for a variety of options. According to the appearance, smoothness and other characteristics, or to select the cleaning surface. Surface in terms of cleaning is not as easy as it is sometimes, the existing test surface may be desirable. The choice of surface layer may affect the type of choice, the choice of the surface layer in turn may affect the choice of material grade, because the different levels of surface layer, the durability of the surface layer are also different. Strong level of corrosion resistance in corrosive solution (the lower alloy content will corrode steel) in the surface layer remains bright. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Chemical elements are known to have more than 100 kinds of industrial materials used in steel can be encountered in about more than 20 kinds of chemical elements. For people in the fight against corrosion for long term practice of this particular form of stainless steel series, the most commonly used in a dozen elements, in addition to the basic elements of the composition of steel other than iron, the performance of stainless steel and organizations most affected. The elements are: Carbon, Chromium, Nickel, Manganese, Silicon, Molybdenum, Niobium, Titanium and Miobium, Nitrogen,Copper, Cobalt, Aluminum, Sulfur and Selenium.  These elements, in addition to carbon, silicon, other than nitrogen, are located in the periodic table of chemical elements of transition. In fact the application of the stainless steel tube industry at the same time there are several elements as well as a dozen, when the number of elements co-exist in a continuum of stainless steel tube, they separate the impact of the presence of more much more complex, because in this cases not only have to consider the role of the various elements of their own, and they should pay attention to the impact of each other, so the organization decided to stainless steel pipe of various elements in the sum of the impact. 1. Various elements on the performance of stainless steel and the impact and role of organizations 1-1. Chromium in the stainless steel a decisive role in stainless steel is a decision of only one element, that is, chromium, stainless steel each contain a certain amount of chromium. To date, no non-chromium stainless steel. Chromium stainless steel performance decision has become the main element, the fundamental reason is to add chromium as an alloying element, the internal contradiction of campaign in favor of resistance to the development of corrosion damage. Such a change can be obtained from the following description: 1. Chromium Fe-based solid solution so that the electrode potential to improve  2. Chromium electronic absorption of iron so that iron-passivated  Anodic passivation is due to be prevented from arising from reaction of metal and alloy corrosion resistance phenomenon can be improved. Passivation of metals and alloys constitute the theory of many major film theory, deals with the electronic order of adsorption. 1-2. Carbon in the stainless steel tube in the dual nature of Carbon steel is the industry one of the key elements, steel and organizational performance to a large extent determined by the carbon content in steel and its distribution in the form of the impact of carbon stainless steel is particularly significant. Carbon in the stainless steel on the impact of organizations mainly in two ways, on the one hand is stable austenite carbon element, and the extent of the role of a large (approximately 30 times for nickel), on the other hand, as a result of the affinity of carbon and chromium is large, with the formation of chromium – series of complex carbides. Therefore, the candle from the intensity and decay properties, both in terms of carbon in the role of stainless steel are mutually contradictory. Recognizing the impact of the law, we can use from different requirements of different carbon content stainless steel. For example, most widely used in industry, but also the stainless steel at least – 0Crl3 ~ 4Cr13 five standard steel grade chromium amount is 12 ~ 14%, that is, the carbon to form chromium carbide and chromium factors taken into account after determined that the purpose is to make the combination of carbon and chromium as chromium carbide, the solid solution of chromium in the amount of not less than 11.7% of the minimum amount of chromium. No. 5 on the steel is due to the different carbon content, strength and corrosion resistance is also differentiated, 0Cr13 ~ 2Crl3 better corrosion resistance of steel but lower than the 3Crl3 and 4Cr13 strength steel, used in the manufacture of the structure of many parts, after As the No. 2 steel with higher carbon intensity will be high and more used in the manufacture of springs, cutting tools, such as high strength and wear-resistant parts. Another example is in order to overcome the 18-8 Cr-Ni stainless steel intergranular corrosion, can be carbon steel to 0.03% below, or by adding chromium and carbon affinity than the larger elements (titanium or niobium), so that does not form a carbide chromium, Another example is when the high hardness and wear resistance as a major requirement, we can increase the carbon content of steel at the same time to suitably increase the amount of chromium so that not only satisfy the requirements of the hardness and wear resistance, but also take into account – will be corrosion-resistant function, used for industrial bearings, has a stainless steel blade measuring and 9Cr18 and 9Cr17MoVCo steel, although the carbon content as high as 0.85 ~ 0.95%, due to their chromium also increased accordingly, it is still guaranteed the corrosion resistance of requirements. Generally speaking, the current industry access to the application of the carbon content of stainless steel pipe are relatively low, most of the carbon content of stainless steel in the 0.1 ~ 0.4%, and acid-resistant carbon steel with 0.1 to 0.2% of the majority. Greater than 0.4% carbon content of stainless steel grade is only a small fraction of the total, which is used because in most conditions, to corrosion-resistant stainless steel is always the primary purpose. In addition, the lower carbon content is also a process for some requirements, such as the ease of welding and cold deformation. 1-3. Nickel in the role of stainless steel and chromium in the play after the Nickel is an excellent corrosion-resistant materials, is also an important steel alloying elements. Nickel in the austenitic stanless steel pipe is the formation of the elements,such as 304,316,321.but the low-carbon steel to obtain pure nickel austenite, the volume of nickel to achieve 24%; and only when 27 percent nickel steel, in some medium resistance significant changes in corrosion. Thus alone can not constitute a nickel stainless steel. But at the same time the existence of nickel and chromium in the stainless steel, the nickel-containing stainless steel but has many valuable properties. Based on the above circumstances, we can see that nickel as alloying elements in the role of stainless steel is that it allows high-chromium steel changes, so that corrosion resistance of stainless steel and certain to improve process performance. 1-4. Manganese and Nitrogen can substitute for Ni-Cr-Ni stainless steel Cr-Ni austenitic steels Although many of the advantages, but in recent decades as a result of nickel-based heat-resistant nickel alloy and the heat below 20% of the large number of strong steel development and applications, as well as the growing chemical industry of the increasing demand of stainless steel The greater the amount of the nickel deposits less concentrated in a few areas, it appeared in the world and the need for nickel in the conflict area. Therefore, in stainless steel alloys and many other fields (such as a large forging steel, tool steel, heat strong steel, etc.), especially the lack of nickel resources of the country, carried out extensive section of nickel and nickel on behalf of other elements in the scientific research and production practice, in this regard the research and application is based on a relatively large number of manganese and nitrogen to replace the stainless steel and heat-resistant nickel steel. For the role of manganese and nickel austenitic similar. But to be more exact, the role of manganese does not lie in the formation of austenite, but it reduced the critical quenching rate of steel in cooling to increase the stability of austenite and suppress the decomposition of austenite, so that the formation of high temperature austenite to room temperature is maintained. In improving the corrosion resistance of steel, the manganese plays a minor role, such as manganese steel increased from 0 to 10.4% change, do not make steel in the air with the acid corrosion resistance of significant change. This is because the manganese to iron-based solid solution to increase the electrode potential does not help the formation of the protective role of the oxide film is very low, so the industry although some of the austenitic manganese steel alloys (such as 40Mn18Cr4, 50Mn18Cr4WN, ZGMn13 steel, etc.), but they can not be used as the use of stainless steel. Manganese in steel is about the role of a stable austenitic nickel half, that is 2% of nitrogen in steel is the role of austenite stability and the role of larger than nickel. For example, to save with 18% chromium steel austenitic at room temperature under the body to manganese and nitrogen on behalf of low-nickel stainless steel and nickel chromium nickel element nitrogen does not induce manganese steel has been applied in industry, and some has successfully replaced the classic chrome-nickel stainless steel 18-8. 1-5. Stainless steel Titanium or Niobium Canada is to prevent intergranular corrosion. 1-6. Molybdenum and Copper can increase some of the corrosion resistance of stainless steel. 1-7. Other elements on the performance of stainless steel and organizational impact More than nine major elements of stainless steel performance and the impact of organizations, in addition to these elements and organizational performance of stainless steel elements of a greater impact, the stainless steel contains a number of other elements. Some, like steel and general for the regular deposit of impurity elements, such as silicon, sulfur and phosphorus. Also some specific purpose in order to join, such as cobalt, boron, selenium, and other rare earth elements. From the stainless steel corrosion resistance of the nature of the main, these elements have been discussed in relation to the nine elements are non-key aspects, although the case, but can not be completely ignored because their performance of stainless steel and organizations have also taken place in the same impact. Silicon is a ferrite forming element, in general, always keep the stainless steel for the impurity elements. Cobalt as alloying elements in steel by the application of small, this is because the high price of cobalt and in other ways (such as high-speed steel, carbide, cobalt-based heat-resistant alloys, magnetic or hard magnetic alloy, etc.) has a more important purposes. Stainless steel in the general increase in the cobalt alloy elements for not more commonly used stainless steel, such as 9Crl7MoVCo (including 1.2-1.8% cobalt) plus cobalt, the purpose is not to improve corrosion resistance and to improve hardness, which are mainly used for stainless steel slicing machinery manufacturing cutting tools, such as scissors and blades. Boron high-chromium ferritic stainless steel Crl7Mo2Ti plus 0.005% of boron, can in boiling 65% acetic acid can enhance the corrosion resistance. Add small amount of boron (0.0006 ~ 0.0007%) austenitic stainless steel will enable the plastic to improve the thermal state. A small amount of boron due to the formation of low melting point eutectic, so that when austenitic steel welding hot cracking tendency to increase, but contains more boron (0.5 ~ 0.6%) when it prevents the emergence of hot cracking . When containing 0.5 ~ 0.6% of boron, the formation of austenite – two-phase boride organizations to lower the melting point of weld. Coagulation bath temperature is below half the melting zone, the base metal in the cooling of the tensile stress generated by the liquid is. Solid- state under the weld metal, is at this time without causing cracks even in the near seam zone formed a crack, it can be in liquid – solid metal by filling the pool. B-containing austenitic stainless steel of the Cr-Ni in the atomic energy industry has a special purpose. Phosphorus in the general impurity elements are stainless steel, but its in danger of austenitic stainless steel in general is not as significant in steel, it allows a higher concentration, if the information up to 0.06%, to control in favor of smelting. Inpidual austenite manganese steel output of about 0.06% phosphorus (such as steel 2Crl3NiMn9) and 0.08% (for example, steel Cr14Mnl4Ni). The use of phosphorus on the strengthening of the role of steel as well as age-hardening increases phosphorus alloying elements of stainless steel, PH17-10P steel (containing 0.25% phosphorus) is a PH-HNM steel (containing 0.30 P) and so on. Sulfur and selenium in the general stainless steel is also often of impurity elements. However, China and Canada to the stainless steel 0.2 ~ 0.4% of sulfur, can improve the cutting performance of stainless steel, selenium also has the same effect. Sulfur and selenium to improve the cutting performance of stainless steel because they reduce the toughness of stainless steel, such as the 18-8 Cr-Ni stainless steel in general the impact of the value of up to 30 kg / cm 2. Containing 0.31% sulfur 18-8 steel (0.084% C, 18.15% Cr, 9.25% Ni) the impact of the value of 1.8 kg / cm2; containing 0.22% selenium 18 -8 steel (0.094% C, 18.4% Cr, 9% Ni) the impact of a value of 3.24 kilograms / square centimeters. Both sulfur and selenium to reduce the corrosion resistance of stainless steel, so the practical application of them as a stainless steel alloy of the rare element. Rare-earth element rare-earth element used in stainless steel pipe, the key is to improve the process performance. Crl7Ti such as the steel and steel plus Cr17Mo2Ti a small number of rare earth elements, can be eliminated in ingot caused by hydrogen bubbles and the reduction of cracks in the slab. Austenitic and austenitic – ferritic stainless steel in 0.02 ~ 0.5% increase in the rare earth elements (Ce-La alloy), can significantly improve the performance of forging. Had a 19.5 percent containing chromium, nickel 23% copper and molybdenum austenitic manganese steel, due to thermal processing performance in the past only the production of castings, after the increase of rare earth elements can be rolled into various sections.

Molybdenum effect Molybdenum in pure γ-Fe in the maximum solubility of about 3%, ω (C) ≈ 0.25% ~ 0.30%, the maximum solubility in austenite is about 8%. Molybdenum in pure α-Fe the maximum solubility of about 32%, and decreased with temperature can precipitate Fe3Mo2, to obtain an age-hardening systems. Molybdenum is a ferrite forming element, capacity equivalent to chromium. In the martensitic stainless steel, molybdenum addition to improving the corrosion resistance, but also improve the hardness and strength, and enhance the secondary hardening effect of steel. The role of the stainless steel molds and cutting tools is very beneficial, usually in the martensitic stainless steel in the ω (Mo) <1%. Molybdenum content is too high, will lead to the formation of δ ferrite and have some adverse effects. Molybdenum can expand the scope of reduction of the passive medium, improve strength and corrosion resistance of passive film, anti-H2SO4, HCl,H3PO4, and some organic acids, resistance to pitting and crevice corrosion. Mo can improve the ability of chloride stress corrosion cracking, especially chloride ions in salt or brine case. Solid solution strengthening method using molybdenum austenitic stainless steelimproves the strength and resistance to tempering of martensitic stainless steel capacity. In addition, the molybdenum can also increase the hardenability of steel, high temperature strength and creep resistance. Nitrogen effect Nitrogen is an austenite stabilizing element, can increase the strength of stanless steel. In the austenitic stainless steel or austenitic – ferritic duplex stainless steel, can enhance the resistance to pitting and crevice corrosion, and reduce the ó-phase intermetallic welding at high temperature or precipitation opportunities. Meanwhile, a compound of nitrogen and manganese instead of expensive nickel alloy, as well as the advantages of improving the solubility of nitrogen. With nitrogen and manganese on behalf of low-nickel stainless steel and nickel-manganese nitrogen-free nickel-chromium stainless steel, has received applications in industry. Typical components of such steel 18Cr-5Ni-8Mn-0.15N, than 304 304L austenitic stainless steel grades with higher strength and corrosion resistance. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Nickel is the formation of austenite of alloying elements, but the role of nickel and chromium to only be fully demonstrated. If the simple use of nickel, nickel stainless steel in the low-carbon austenitic phase to obtain pure organizations need to nickel content up to 24% (by mass) or more, in fact, need to reach 27% nickel content (mass fraction), can significantly improve the corrosion resistance of stainless steel, so there is no separate stainless steel to nickel as alloying elements. When the nickel and chromium complex, the nickel role in improving the corrosion resistance of steel can be shown significantly, such as ferritic stainless steel to add a small amount of nickel, can make the single-phase microstructure of ferrite into austenite – Organization of ferrite phase, so that you can to increase its strength by heat treatment. Further increase of nickel content, you can become a single phase of austenite, such as ω (Cr) = 18% of steel with 8% (by mass) of nickel, the availability of fully austenitic. This is widely used in chrome-nickel austenitic 18-8 stainless steel, it with high corrosion resistance and good deformation, welding, and is not magnetic. Nickel in the role of stainless steel and chromium in the play after the Nickel is an excellent corrosion-resistant materials, is also an important steel alloying elements. Nickel in the austenitic stanless steel is the formation of the elements,such as304,316,321.but the low-carbon steel to obtain pure nickel austenite, the volume of nickel to achieve 24%; and only when 27 percent nickel steel, in some medium resistance significant changes in corrosion. Thus alone can not constitute a nickel stainless steel. But at the same time the existence of nickel and chromium in the stainless steel, the nickel-containing stainless steel but has many valuable properties. Based on the above circumstances, we can see that nickel as alloying elements in the role of stainless steel is that it allows high-chromium steel changes, so that corrosion resistance of stainless steel and certain to improve process performance. Nickel in pure α-Fe in the maximum solubility of 25% to 30%, when the stay was still contains carbon in ferrite, the effect is not hardened by solid solution of steel intensive. Passivation of nickel to expand the scope to improve corrosion resistance, especially in non-oxidizing media (such as sulfuric acid) in the.  Nickel-iron carbide formation tendency is weaker than can promote graphitization, and weakly increased the hardenability of steel on steel is not sensitive to cold shock play a role. In carbon and high carbon steel containing an effective concentration, the quenching preferred to retain austenite. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Matching the consumable to the parent material The chemical composition of stainless steel welding consumables is matched with the base or parent material. The chemical analysis (composition) of the consumables used are usually balanced to optimise the welding process and avoid hot cracking. Austenitic stainless steel Low carbon levels are normally used to reduce the risks of intergranular corrosion (intercystalline) following cooling through temperatures from around 850 down to 450 C after weld solidification. Corrosion mechanisms in stainless steel. Consumables such as 19 9 and 19 12 2 with higher carbon levels should give higher strength welds, more suited for high service temperatureapplications. The titanium stabilized steel, 321 and 316Ti are welded with consumables containing niobium, rather than titanium. The very high melting point titanium carbides that would be present in the consumable would be unlikely to melt during the welding process, whereas the niobium carbo-nitrides in the niobium type consumables have lower melting points and are a better choice. Ferrite levels of austenitic consumables are normally balanced between 4 and 12 %, to reduce the risk of hot cracking at temperature just below the solidification point of the weld metal. For welding the special low / zero ferrite grades, intended for special corrosion resistant, cryogenic temperature or low magnetic permeability service conditions, matching low /zero ferrite consumables, such as 18 15 3 L, should be used. Ferritic, martensitic and precipitation hardening stainless steel Generally, either matching consumables, or an austenitic filler with matching chromium and molybdenum contents, can be used. Austenitic fillers are used where good weld toughness is essential, but these are not a good idea where the weld appearance (colour), mechanical strength (in the case of welds between martensitic and precipitation hardening parent material) and physical properties (thermal expansion) need to be matched with the parent material. Duplex stainless steel In contrast to the austenitic consumables, duplex fillers, such as 22 9 3 N L are balanced to produce more austenite in the weld than in the parent metal. This is done to optimise weld mechanical properties and corrosion resistance and is achieved by adding more nickel and usually nitrogen to the consumable than is present in the matched base metal. Compositions of consumables The consumable alloy symbols are common in the European standards. The compositions can vary, however, for the various consumable types between EN 1600, EN 12072 and EN 12073 for the same ‘Alloy symbol’ used in each standard. For each specific consumable type the particular standard should be consulted. As a guide the table below gives the compositions in EN 1600. For these coated electrode types, the type of covering determines to a large extent the usability characteristics of the electrode and properties of the weld metal. Two symbols are used to describe the type of covering: R for Rutile covering and B for Basic covering. A description of the characteristics of each of the types of covering is given in Annex A of BS EN 1600. (See also paragraph 4.3 of the standard) Alloy symbolsChemical composition (% by mass – max unless stated).CSiMnPSCrNiMoOthers130.121.01.50.0300.02511.0/14.0–––13 40.061.01.50.0300.02511.0/14.53.0/5.00.4/1.0–170.121.01.50.0300.02516.0/18.0–––19 90.081.22.00.0300.02518.0/21.09.0/11.0––19 9 L0.041.22.00.0300.02518.0/21.09.0/11.0––19 9 Nb0.081.22.00.0300.02518.0/21.09.0/11.0–Nb-8x%C min, 1.1%max19 12 20.081.22.00.0300.02517.0/20.010.0/13.02.0/3.0–19 12 3 L0.041.22.00.0300.02517.0/20.010.0/13.02.5/3.0–19 12 3 Nb0.081.22.00.0300.02517.0/20.010.0/13.02.5/3.0Nb-8x%C min, 1.1%max19 13 4 N L0.041.21.0/5.00.0300.02517.0/20.012.0/15.03.0/4.5N 0.2022 9 3 N L0.041.22.50.0300.02521.0/24.07.5/10.52.5/4.0N 0.08/0.2025 7 2 N L0.041.22.00.0350.02524.0/29.06.0/9.01.0/3.0N .02025 9 3 Cu N L0.041.22.50.0300.02524.0/27.07.5/10.52.5/4.0N 0.10/0.25 Cu 1.5/3.525 9 4 N L0.041.22.50.0300.02524.0/27.08.0/10.52.5/4.5N 0.20/0.30 Cu 1.5 W 1.018 15 3 L0.041.21.0/4.00.0300.02516.5/19.514.0/17.02.5/3.5–18 16 5 N L0.041.21.0/4.00.0350.02517.0/20.015.5/19.03.5/5.0N 0.2020 25 5 Cu N L0.041.21.0/4.00.0300.02519.0/22.024.0/27.04.0/7.0Cu 1.0/2.0 N 0.2520 16 3 Mn N L0.041.25.0/8.00.0350.02518.0/21.015.0/18.02.5/3.5N 0.2025 22 2 N L0.041.21.0/5.00.0300.02524.0/27.020.0/23.02.0/3.0N 0.2027 31 4 Cu L0.041.22.50.0300.02526.0/29.030.0/33.03.0/4.5Cu 0.6/1.518 8 Mn0.201.24.5/7.50.0350.02517.0/20.07.0/10.0––18 9 Mn Mo0.04/0.141.23.0/5.00.0350.02518.0/21.59.0/11.00.5/1.5–20 10 30.101.22.50.0300.02518.0/21.09.0/12.01.5/3.5–23 12 L0.041.22.50.0300.02522.0/25.011.0/14.0––23 12 Nb0.101.22.50.0300.02522.0/25.011.0/14.0–Nb-8x%C min, 1.1%max23 12 2 L0.041.22.50.0300.02522.0/25.011.0/14.02.0/3.0–29 90.151.22.50.0350.02527.0/31.09.0/12.0––16 8 20.081.02.50.0300.02514.5/16.57.5/9.51.5/2.5–19 9 H0.04/0.081.22.00.0300.02518.0/21.09.0/11.0––25 40.151.22.50.0300.02524.0/27.04.0/6.0––22 120.151.22.50.0300.02520.0/23.010.0/13.0––25 200.06/0.201.21.0/5.00.0300.02523.0/27.018.0/22.0––25 20 M0.35/0.451.22.50.0300.02523.0/27.018.0/22.0––18 360.251.22.50.0300.02514.0/18.033.0/37.0–– Suggested consumables for welding stainless steel Euro Inox publication ‘Welding of Stainless Steels’ tabulates suggested consumables for welding a range of stainless steel base or parent grades. This publication can be viewed or down loaded in pdf format from the Euro Inox web site, www.euro-inox.org by selecting the Materials and Applications sub menu. This table is shown below. Base MaterialWelding ConsumablesEN 10088 NumberAISI GradeEN 1600EN 12072EN 120731.4301304E 19 9G 19 9 LT 19 9 L1.4306/1.4307304LE 19 9 LG 19 9 LT 19 9 L1.4541321E 19 9 NbG 19 9 NbT 19 9 Nb1.4401316E 19 12 2G 19 12 2 LT 19 12 2 L1.4404316LE 19 12 3 LG 19 12 3 LT 19 12 3 L1.4571316TiE 19 12 3 NbG 19 12 3 NbT 19 12 3 Nb1.4438317LE 19 13 4 N LG 19 13 4 LT 19 13 4 N L1.4310301E 19 9G 19 9 LT 19 9 L1.4318301LE 19 9 LG 19 9 LT 19 9 L1.4833309SE 22 12G 22 12 HT 22 12 H1.4845310SE 25 20G 25 20T 25 201.4438317LE 19 13 4 N LG 19 13 4 N LT 19 13 4 N L1.4512409E 19 9 LG 19 9 LT 13 Ti1.4016430E 17 or 19 9 LG 17 or 19 9 LT 17 or 19 9 L1.4510430Ti (439)E 23 12 LG 23 12 LT 23 12 L1.4521444E 19 12 3 LG 19 12 3 LT 19 12 3 L1.4509441E 23 12 LG 23 12 LT 23 12 L1.4113434E 19 12 3 LG 19 12 3 LT 19 12 3 Nb1.4362(2304)E 25 7 2 N LG 25 7 2 N LT 22 9 3 N L1.4462(2205)E 25 7 2 N LG 25 7 2 LT 22 9 3 N L1.4006410E 13 or 19 9 LG 13 or 19 9 LT 13 or 19 9 L1.4021420E 13 or 19 9 LG 13 or 19 9 LT 13 or 19 9 L1.4028420E 13 or 19 9 LG 13 or 19 9 LT 13 or 19 9 L Notes Only the steel number is shown. The original Euro Inox table also has the steel name. AISI is the American Iron and Steel Institute Wire electrodes covered by EN 12072 may use the following prefixes G for GMAW (MIG), W for GTAW (TIG) P for PAW (plasma arc), or S for SAW (submerged arc). Tubular cored electrodes are sometimes referred to as flux cored electrodes. Releated References Welding of Stainless Steels Euro Inox, Materials and Applications Series, vol.3 Welding of Stainless Steels and Other Joining Methods The Nickel Institute, AISI Designers Handbook Series No 9002

Trade Names Associated With Stainless Steel table Note, where ‘Non-SS’ is shown in the Nearest Grade column, this indicates that the trade name as not a stainless steel. Use the ‘Ctrl’ and ‘F’ keys to ‘find’ a particular name.Trade NameNearest GradeDescription1925hMo1.4529Austenitic20% chromium, 25% nickel, 6% molybdenum superaustenitic stainless steel (Krupp Thyssen Nirosta)22051.4462 Duplex22% chromium, 5% nickel, 3% molybdenum duplex stainless steel253MA1.4835 Heat Resisting21% chromium, 11% nickel, 1.5% silicon heat resisting stainless steel (AvestaPolarit)254SMO1.4547Austenitic20% chromium, 18% nickel, 6% molybdenum superaustenitic stainless steel (AvestaPolarit)520B1.4594Martensitic-PH13.5% chromium, 5.5% nickel, 1.5% molybdenum precipitation hardening grade904L1.4539Austenitic20%chromium, 25% nickel, 4.5% molybdenum austenitic stainless steelAbrazoNon-SSBritish Steel wear platesAbroNon-SSWear plates from James Fairley Abra Service Division 0121-327 7522Alencoflex–Flexible hoses with stainless steel braid outer covers from Alenco Hilyn, EnfieldAlloy 1601.47131.4713 Heat resisting grade 7% Cr, Al – Bohler UK 0121-552 2575 – See Sicromal 8Aluchrom–VDM Trade Name for Fe-Cr alloysAquamet 22Nitronic 50Nitronic 50 type for propeller shaft applications – see Clements Engineering (St.Neots)Ltd for detailsArmourcote–PTFE stainless composite coating for reducing friction from Armourcote Surface TreatmentsBattle–Stainless steel holloware from GW Pearce, BirminghamBrightrayNon-SSNickel alloys from Inco AlloysBundyNon-SSBrake pipe material from Armco also see FulbraizChemicoNon-SSGeneral purpose cleaner for stainless steel from The County Chemical Company, Birmingham 0121-744 2294Chichester–Stainless steel ware from Goodwood Metalcraft TEL 01243-784626 (also see Dexam International)ColorcoatNon-SSPrepainted mild steel strip from British Steel (Corus Strip products)Compass B555Non-SSWear plate with Brinell Hardness of 555HB – Sleema Engineers TEL 01922-408088Corrbloc–Mild steel strip clad with stainless steelCorten ANon-SSWeathering steel from Corus Strip (British Steel)Corten BNon-SSWeathering steel from Corus Plates (British Steel)Cres–US military abbreviation for “Corrosion Resistant” implies any stainless steel ie not grade specificCrominox–Aciers Crominox, Luxembourg now merged with Cromweld Steels as a 3Cr 12 supplierCromweld 3Cr121.4003 Ferritic3Cr12 ferritic stainless from Cromweld Steels, Stoke on Trent TEL 01782-374139Cronifer–Krupp VDM Trade Names for stainless steelsCronix–Krupp VDM Trade Names for Ni-Cr heating element alloysCuniferNon-SSKrupp VDM Trade Names for copper-nickel alloysDamac DL12Non-SSSpot test paste supplied by Broadway ProductsDelcromeNon-SSSee Stellite – Product of Deloro Stellite, SwindonDeloroNon-SSSee Stellite – Product of Deloro Stellite, SwindonDessoxNon-SSOakite Ltd descaling compoundsDuranel–Clad plates involving combinations of stainless steel, aluminium and copperDurasteelNon-SSSteel sheet with organic coating over zinc-nickel plated surface, originally from Japan (Nissan). Cape-Durasteel, Wellingborough TEL 01933-440555Durbar304, 316Floor or chequer plate – 304 & 316 now imported from Belgium (ALZ), stocked by Ancon CCLDureheteNon-SSHeat resisting bar grades for bolting applications from Corus Engineering Steels, RotherhamE-Brite 26-1–Ferritic stainless steel with 26% Cr and extra low carbon (0.005% Max) from Airco Vacumetal, USAEM 528–Rolls Royce specification for 448 type turbine blade steelEssheteNon-SSHeat resisting steel grades from Corus Engineering SteelsEzeform–Patterned stainless steel strip from Atlas Steels, Canada for roofing applicationsFAK 2232205Also see “FALC 223” Duplex Stainless Steel of a 2205 type from KruppFDP1.4541Austenitic“Firth’s Decay Proof” (321) – see Firth Vickers ‘Staybrite’Fecralloy–Heat resistance wire, strip, bar grade 20% Cr, 5% Al,0.1% Y (yttrium) from Resistalloy, Sheffield TEL 0114-244 8634Ferralium 2551.4507 DuplexSuper duplex stainless steel available from Langley Alloys Ltd, Newcastle-under-LymeFerritescope–Magnetic permeability meter calibrated to show percentage of ferrite in austenitic stainless steels. from Fischer InstrumentationFerro-Di–Die casting process for stainless steel, GKN Crewe Technical CentreFMB1.4401/1.4436Austenitic“Firth’s Moly Bearing” (316, 2.25-3.0% Mo) – see Firth Vickers ‘Staybrite’Fliteline–PTFE flexible tubing with stainless steel braided wire sheathing for steam & water tubes from Unitubes, Slough TEL 01753-34931GenkleneNon-SSSolvent containing trichloroethylene (not advised for health & environment reasons)Hadfields Manganese SteelNon-SSManganese steel, 12-14%Mn, for extreme wear resistant applications. Available from Corus Scunthorpe 01724-405779 Tim PeregrineHastelloyNon-SSNickel based alloysHaynes AlloysNon-SSNickel based alloys, see Haynes Alloys brochures on shelf No2, cabinet No1 TEL 0161-223 5054HexmetalNon-SSArmours for refractory linings from Causeway Steel Products, Gravesend TEL 01474-67871Hi-Proof316LNNitrogen bearing austenitics eg 316 bar for reinforcement, warm worked for 460 N/mm2 strength classHR 3C31025Cr – 20Ni – Nb – N variant of 310 as sulphurizing resistant grade from Sumitomo Metal Ind.HWT430TiHot Water Tank grade similar to 430Ti, with 19% Cr from Allegheny LudlumHydroloy–Hydroloy HQ913 low erosion weld deposit austenitic grade available as weld deposit electrodes from Deloro StelliteHyform 4091.4512 FerriticAvestaPolarit 409 type with titanium for automotive silencer tubing etcHyplus 29Non-SSCorus Plates productHypressNon-SSC steel strip grade from Corus Strip Products, BrinsworthImmac 51.4845 Heat ResistingHeat resisting 310 (25 / 20) type originally a Firth Brown trade nameImmaculate V–Heat resisting 310 (25 / 20) with vanadiumIN744X–Micro duplex super plastic experimental stainless steelIncocladNon-SSNickel cladding alloysIncoloyNon-SSNickel heat resisting alloys (Incoloy DS 37Cr – 18Ni , Incoloy 800 same as Esshete 800)InconelNon-SSNickel alloysInox–French (Spanish, Italian) general term for “stainless”, not grade specificInvar (Nilo 36)Non-SSNickel alloy with 36% iron zero thermal expansion rateJethete–Martensitic stainless steel for aircraft turbine blades & engine casingsKanthalNon-SSHeat Resistant & heating element alloys for furnace heating applications from Kanthal Ltd, Stoke on Trent TEL 01782-224800Kromar D70–Cobalt containing stainless steel used for cluster bomblet flights made by Hunting Engineering. Believed to be an obsolete application.Kunifer 10Non-SSBrake pipe grade from Yorkshire Imperial Metals TEL 01532-701107M153D–Proprietary specification for a 316 free machining type with titanium additions type from IMI WittonMacalloyNon-SSReinforcement bar from Allied Steel & Wire (McCalls) TEL 0114-242 6704MeehaniteNon-SSCast Irons from The International Meehanite Metal Co, Reigate TEL 01737-244786MEKNon-SSMethylethyl ketone – solvent for removing plastic film & adhesives from stainless steel sheetMeten 91.4828 Heat ResistingHeat resisting stainless steel grade similar to Red Fox 34 from Mechanical Engineers, LondonMonelNon-SSNickel-copper alloysMu MetalNon-SSAlloy of 77% Ni,5% Cu, 4% Mo & Iron – Soft magnetic alloy with a high magnetic permeabilityNACENon-SSNational Association of Corrosion Engineers (US)Ni-HardNon-SSAbrasion resistant castings 3.5/4.5 % NiNichromeNon-SSNickel Chromium heat resisting alloys for furnace heating elementsNicorrosNon-SSNickel-copper alloys.NicroferNon-SSVDM Trade Name for Ni-Cr-Fe & Ni-Cr-Fe-Mo alloys (TEL 01372-67137) – Nicrofer 3220=Incoloy 800,Nicrofer 3718=Incoloy DS,Nicrofer 4221=Incoloy 825,Nicrofer7216=Inconel 600,Nicrofer 7520=Nimonic75NiloNon-SSLow expansion nickel alloyNimarNon-SSMaraging Steels from Corus Engineering SteelsNimonicNon-SSNickel based heat resisting eg Nimonic 75, 80, 90NiresistNon-SSNickel cast iron from Lennox Foundry TEL 01322-383281Niroflex–Stainless steel safety clothing – CMT Industrial Supplies, Swansea 01792-798600Nirosta–Krupp Thyssen Nirosta (KTN) trade names for stainless steels, use Werkstoff numbers for grades eg “Nirosta 4301” as 1.4301 (304)NitralloyNon-SSOld ESC trade names for nitriding alloys En 41A & B, try Henry Whitham,Sheffield TEL 0114-244 0744Nitronic 50–Also marketed as “Aquamet”NovametNon-SSMetal flakes from Hart Coating Technology TEL 01384-291513Nu Eli t–18/2 ferritic stainless, titanium stabilized ferritic stainless (low interstitial) – old Nyby Uddeholm brandsNu Monit–Titanium stabalised ferritic stainless (low interstitial) – old Nyby Uddeholm brandsNuovinox–Aberneath Industries clad stainless bar products TEL 01639-820666Oztelloy–Stainless steel plating on various substrates – Tri-Kem Ltd Wellingborough – 01933-228877PerniferNon-SSKrupp VDM Trade Names for 36% nickel-iron low expansion alloyPlanclad–Ductile Planetary Mill Ltd clad strip 304L, 430 & 410 stainless on carbon steel substratePolarisNon-SSPolaris stainless steel reviver (cleaner-polisher for table ware, sinks etc) – Dexam InternationalPoral–Porous sheet and strip (Pechiney Ugine Kulmann), not now availableProdec–Avesta Sheffield free machining grades (Degerfors plate & bar)Red DiamondNon-SSWear resistant plates (Spartan Redheugh Ltd, Gateshead now closed)Red Fox–Corus Engineering Steels Heat Resisting types RF310, RF309 & RF34 (RF34 also known as Meten 9 – 1.4828)Regaflex316Flexible tube for flue linings in 316 type from Rega Metals ProductsRemanit–Originally Thyssen trade name — usually has werkstoff number added eg Remanit 4301Rigitube–Patterned tube for vehicle handrails (grab rails) – Rimex (Rigidized Metals)Sanicro–Sandvik trade name eg Sanicro 28 (UNS N08028)Sanmac–Sandvik improved machinability barSea-Cure446Ferritic grade for seawater heat exchanger tubing- 26Cr, 3Mo, 2.5Ni UNS S44660Sicromal 101.4742 Heat ResistingHeat resisting grade 17% Cr, AL – (Energy Alloys Rotherham 01709-788000)Sicromal 121.4762 Heat ResistingHeat resisting grade 24% Cr, Al – (Energy Alloys Rotherham 01709-788000)Sicromal 81.4713 Heat ResistingHeat resisting grade 7% Cr, Al – Bohler UK 0121-552 2575 as Alloy 160 or Energy Alloys Rotherham 01709-788000Silver Fox–Samuel Fox, later British Steel (Corus) Engineering Steels trade namesSistema Men–Loose lay stainless steel floor tiles from Inova Furniture Contracts Ltd, LondonSnaptite–Quick fitting couplings for fluid transfer lines in stainless steel with teflon seals from Adflow International Tel 01734-713733Sno-Trik–High-pressure stainless steel pipe fittings from Techmation Ltd (UK agents for Sno-Trik Co.) Tel “01-958 3111”SS (41,400)Non-SSJapanese Structural GradesSt (37,52 etc)Non-SSGerman Structural Grades See BSEN 10025Staballoy–UNS S28200 – 17 Cr, 20 Mn 0.55 NStaybrite–Generic trade names for Firth Vickers grades, such as FSL,FDP, FMB etcStavax420Tool steel type 0.38 C 13 Cr ie martensitic 420 type originally Uddeholm, later VEW Special Steels 0121-552 5681Steelex304,316Stainless steel roofing systems from Lee Steel Strip, Sheffield (now AvestaPolarit Strip)SteelitNon-SSComplete Paint system for SS items from Stainless Steel Coatings IncStelliteNon-SSCobalt hardfacing alloys – Deloro Stellite, Swindon TEL 01793-822451StelvetiteNon-SSCorus Strip plastic coated carbon steel strip productsSupatube–Welded SS Tube – weld bead drawn for hygienic & heat exchanger applications – Stelco Hardy, TreorchySuperDux 64–Super plastic duplex stainless steel from Nippon Yakin Kigyo Co 25 Cr, 6.5 Ni, 3.2 MoTemet 25Nitronic 50Propeller shaft bar grade from Teignbridge Propellers Ltd, Newton Abbott TEL 01626-333377 FAX 01626-60783Thyroplast–Thyssen stainless steel generic trade name, Werksoff number used to identify specific gradeTriclad–Sandwich with mild steel core & stainless surfaces from Allegheny, USA – see TriplyTrinsul–Insulated profiled stainless steel sheet from Precision Metal Forming, Cheltenham 01242-527511Triply–Sandwich with mild steel core & stainless surfaces from Universal Cyclops, USA – see TricladTufftriding–Salt bath nitrocarburising. Improves wear, seizure and galling resistance of 304 and 316 austenitic stainless steels, available from Keighley Laboratories Ltd.Uginox–ArcelorMittal Stainless Europe trade names covering range of steel gradesUltiMet–180 & 240 grit satin finishes from WS Metalstock LtdUranus–Creusot Loire trade names examples Uranus B6, 50, 45N, 47 etc – stockist is James Fairley AthenaV2A304Krupp (Germany) trade names covering 304 typesV4A316Krupp (Germany) trade names covering 316 typesWaspalloyNon-SSNickel-chromium alloysWaukeshaNon-SSNickel alloy for anti-galling applications from Dewramet Ltd, GlasgowZalutiteNon-SSAL, Zn Si coating on mild steel for car exhausts – Corus Strip ProductsZeron 1001.4501 DuplexSuper duplex stainless steel (Rolled Alloys)ZintecNon-SSZinc coated mild steel from Corus Strip Products

Sometimes stainless steel is considered to be an expensive material. However, experience has shown that using a corrosion resistant material in order to avoid future maintenance, downtime and replacement costs can produce economic benefits which far outweigh higher initial material costs. Life cycle costing (LCC) quantifies all the costs – initial and ongoing – associated with a project or installation. It uses the standard accountancy principle of discounted cash flow to reduce all those costs to present day values. This allows a realistic comparison to be made of the options available and the potential long term benefits of using stainless steel to be assessed against other material selection. The present day value represent the amount of money which would have to be invested today in order to meet all the future operating costs – including running costs, maintenance, replacement and production lost through downtime. These are added to the initial costs to give the total LCC: whereAC = initial materials acquisition costs IC = initial fabrication and installation costs N = desired service life of project in years i = discount rate (calculated from interest and inflation rates) OC = operating and maintenance costs in year n LP = lost production and downtime costs in year n RC = replacement costs in year n Once the cost data have been gathered, the calculation of the life cycle cost is straightforward. Software packages are available which prompt the user to collect the relevant data, carry out the calculation and allow different options to be compared easily. Example (Refer to “Applications for stainless steel in the water industry”) Galvanised carbon steel and Type 316 stainless steel were both candidate materials for ductwork to remove odorous fumes in a sewage inlet works. The galvanised steel required a multi-stage site-applied painted coating whereas the stainless steel could be installed in a single operation. The galvanised steel was expected to need maintenance every 5 years, and replacement after 15 years. The stainless steel equipment was designed for a 30 year service life, with maintenance every 10 years. A 10% interest rate and 5% inflation rate were assumed, giving a discount rate of 4.76%. Not only was the stainless steel option only slightly more expensive initially (because of the lower installation cost) but it showed a distinct life cycle cost advantage following the anticipated replacement of the galvanised steel plant after 15 years (refer to graph). The stainless steel option was chosen. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The traditional ‘free machining’ stainless steel have been based on sulphur (S) additions in the UK or alternatively, selenium (Se) additions, which have been favoured in the United States. The addition of these elements is in the region of 0.15 – 0.35%. In practice, it is impossible to obtain the selenium treated steel from European producers. These additions form manganese rich sulphides (selenides), which provided they are evenly distributed through the stainless steel, act as chip breakers for machining operations and so can offer higher machining speeds and improved cutting tool life. These ‘non-metallic’ inclusions can also provide a source of solid lubricant to the tool / workpiece interface which may in turn also result in improvements in surface finish. British standard free machining grades Free-machining types have been specified as alternatives to some of the popular grades, but grade rationalisation has resulted in some of the options being withdrawn from standards. EN 10088 grades with permitted sulphur additions Although purpose designed free machining grades are limited in the European standard, EN 10088 does allow machinable grade variants with 0.015 / 0.030% S additions to some grades. Un-Treated TypeMachinability AdditionBS Free Machining GradesNearest BS EN 10088 Grade420S416S211.4005416S29–416S371.4029Se416S41–431S441S29–Se441S49–304S303S211.4305Se303S41–321S325S21–316Se326S36–316S–1.4598 BS EN 10088 grades with permitted sulphur additions Although purpose designed free machining grades are limited in the European standard, BS EN 10088 does allow machinable grade variants with 0.015 / 0.030% S additions to some grades. Selenium additions are not allowed in this European standard. 1.4006410 type – 0.08 / 0.15 %C1.4021420 type – 0.16 / 0.25 %C1.4028420 type – 0.26 / 0.35 %C1.4031420 type – 0.36 / 0.42 %C1.4057431 type – 0.12 / 0.22 %C1.4112440B type – 0.85 / 0.95 %C1.4125440C type – 0.95 / 1.20 %C1.454217/4 PH type1.4307304L type1.4541321 type1.4401316 type1.4404316L type Proprietary enhanced machinability grades Proprietary sulphur and selenium grades have been marketed, including ferritic 430 and martensitic 440 types. Proprietary alternatives based on controlled non-metallic inclusion levels are also available. These are usually based on calcium de-oxidisation steelmaking techniques and include grades based on 304, 316 austenitic, 2205 (1.4462) duplex and 17-4 PH (1.4542) precipitation hardening types. The levels of calcium or oxide type inclusions are not part of the grade specification, the grades being identified only by their proprietary names. Many manufacturers of stainless steel bars market these enhanced machinability grades with brand names, for example: CompanyBrandAcerinoxRoldamaxCogneIMCOOutokumpuPRODECSchmolz and BickenbachUgimaValbrunaMaxival Other additions deliberately made to enhance machinability include copper. This helps improve machinability of austenitic types by reducing the cold work hardening tendency. (Copper works like nickel as a powerful ‘austenite’ phase stabiliser, reducing the formation of strain induced martensite during cold working). The cold forging grades are copper bearing types. Disadvantages of free machining grades The ‘machining’ grades may not perform as well as the ‘standard’ grades, from which they are derived. When specifying and working with these types of stainless steels it is important to bear in mind that they can be inferior to the un-treated types.

In the past, stainless steel used in many applications for high-grade, aesthetic considerations, to improve the standard of living demand. Stainless steel isn’t the people indispensable necessities of life ‘s. From the” energy-saving emission reduction”, to avoid the” greenhouse effect” in a new perspective, stainless steel shall be treated as the sustainable development of the necessities of life. In the process of production, stainless steel compare with ordinary carbon steel, has obvious benefits of energy conservation and emission reduction. Generally speaking, in the iron and steel production. Adopted from the electric furnace of the steel began to hot rolled stainless steel tube sheet. Production of stainless steel more than 55% energy saving than carbon steel. From the use of electric furnace steel, the hot rolledstainless steel tube sheet products .So far, stainless steel short process production technology of steel CO2 emissions to 507 kilograms; including the use of ironmaking system begins. Considering the short technological process of stainless steel production accounts for about 70% of the total output of stainless steel, the long process of carbon steel output accounted for about the total yield of 90% carbon steel. The overall average social comprehensive energy consumption of per ton steel, stainless steel is 383.5 kilograms, average social comprehensive energy consumption of carbon steel 590.5 kilograms. Social average stainless steel CO2 emissions to 912.9 kilograms, average social carbon steel CO2 emissions to 1724.7 kg. By this is visible, the production of 1 tons of hot rolled stainless steel tube sheet, than the production of 1 tons of ordinary hot rolled carbon steel tube sheet, can save more than 35% of energy consumption, can reduce the more than 47% of the CO2 emissions. Two in the application areas, the more obvious advantages of stainless steel. Because the stainless steel is a boutique, with no rust, corrosion resistance, appearance and high strength, one hundred percent recyclable and other characteristics, in the practical application, can further show the energy saving and emission reduction of social benefits. For example, using the hot rolled stainless steel tube sheet to produce a new type of stainless steel and ordinary carbon steel manufacturing trucks using domestic raw general-purpose gondola car compared with stainless steel truck wagon, can reduce the initial steel consumption 15%, the entire life cycle can reduce the steel consumption of about 55%. According to the life cycle of tons of coal consumption calculation of steel, can save more than 75%. So, every increase production 1 tons of stainless steel, it can replace more than 4 tons of carbon steel. Only stainless steel manufacturing process and Application Process saving steel the factors to consider than ordinary carbon steel, stainless steel 84.25% energy saving, reducing emissions of CO2 87.16%. Further consideration of stainless steel in nuclear applications make nuclear energy promotion becomes possible, and thermal power compared to further reduce CO emissions. In water supply and drainage system, by reducing water pollution and waste thereby further reducing CO2 emission. The applications in water treatment, in seawater desalination aspects of the application, in the clean food applications, in order to raise energy efficiency, the application in one hundred percent recyclable applications etc. Stainless steel,” energy-saving emission reduction”, to avoid the” greenhouse effect ” effect is bigger.

Unlike carbon steel, there have not been listings of open section sizes for stainless steel structural sections, until Sections Directory in May 2004. This gives the full range of ‘standard’ stainless steel sections that are readily available and the companies who supply them. The directory distinguishes between producers and distributors as well as showing the main stainless steel grades available from each supplier across the complete size range. Hollow Sections The hollow sections listed in the directory are available in stainless steel grades 1.4301 (304), 1.4307 (304L), 1.4401 (316), 1.4404 (316L) and1.4571 (316Ti). Normally hollow sections are welded from strip or plate. The design strength of ‘as-formed’ austenitic stainless steel tube is generally higher than for the same grade of annealed tubes. For most structural applications either annealed or ‘as-formed’ supply conditions can be expected to provide comparable corrosion resistance. Section Tables Available The directory can be downloaded from Structural Sections. Section tables available Manufacturing MethodSection TypeHot Rolled (Part 1.1)Channels.Equal Sided Angles.Unequal Sided Angles.Unequal T-ProfilesHot Extruded & Special Sections (Part 1.2)Z Profiles.I Beams.Channel (parallel).Channel (taper).Equal Sided Angles.Unequal Sided Angles.Equal T Profiles.Unequal T profilesCold Formed Sections (Part 2).RolledEqual Sided Angles.Unequal Sided Angles.Channel sFormedZ Profile.Special Sections (doors and windows)DrawnEqual Sided Angles.Unequal Sided Angles.T ProfilesWelded Sections (Part 3)I Profiles.H Profiles.Channels.Equal Sided Angles.Unequal Sided Angles.Equal Sided T Profiles.Unequal Sided T ProfilesCircular Hollow Sections (Part 4.1).Square Hollow Sections (Part 4.2).Rectangular Hollow Sections (Part 4.3). Approximate Range of Available Dimensions Circular Hollow Sections 1.0-30mm thick 6.0-914mm diameter Square Hollow Sections 1.0-25mm thick 10 x 10-800 x 800 width Rectangular Hollow Sections 1.0-25mm thick 20 x 10-900 x 600mm width. Approximate range of available dimensions: Circular hollow sections:thickness: 0.25 to 8.0 mm,diameter: 3 to 250 mmRectangular hollow sections:thickness: 1.0 to 8.0 mm,width: 20×10 to 300×150 mmSquare hollow sections:thickness: 1.0 to 8.0 mm,width: 10×10 to 300×300 mmOval hollow sections:thickness: 1.0 to 3.0 mm,diameter: 61×37 to 121×76 mm Open sections Open sections, including many masonry support section types, can be press formed from flat sheet or plate. These are available as standard products or to special design and include formed and welded sections, such as I sections made up of two channels welded, back to back. Thicker sections are manufactured from welded flat plate, but may be subject to final straightness limitations. Heavier sections sizes may be hot formed, either by extrusion or rolling. Open sections can usually be sourced in stainless steel grades 1.4301 (304) and 1.4401 (316). Some less common and more ‘specialised’ grades, including 1.4713 (a 6-8% chromium heat resisting ferritic steel) are also available. For information on how to select the most suitable grade for internal or external building applications, see articles Selection of stainless steels for building internal applications and Selection of stainless steels for building external applications Stainless Steel bars Stainless Steel Round bars, stainless steel square bars, stainless steel rectangular and hexagonal solid bars are generally widely available in stainless steel grades 304 (1.4301) and 316 (1.4401) and additionally in other more specialised stainless steel grades, including duplex 2205 (1.4462). Approximate range of available dimensions: Circular:diameter: 2 to 450 mmFlats:thickness: 3.0 to 25 mm, width: 12×150 mmSquare:width: 3 to 300 mmHexagonal:across flats: 5 to 100 mm Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

To ensure the highest quality gas at the point-of-use (POU), efforts have focused on the selection of the appropriate materials for construction of the distribution system. Traditionally, 316 stainless steel has been employed in the construction of subcomponents for use in reactive gas distribution systems. The proper selection of the stainless melt can improve thecorrosion resistance in UHP gas systems. In the case of high purity semiconductor gas filter assemblies, it is important to specify the proper chemistries, grain size and inclusions2. In addition, the suitability of the material to be formed, mechanically polished, and electropolished (EP) must also be evaluated. The careful selection of the 316L stainless steel utilized in the fabrication of filter assemblies is critical, as materials of similar composition can perform very differently. Wang and coworkers noted variability in the corrosion behavior of steel alloys with bulk compositions that are virtually identical when exposed to moist HCl3. Smudde et al.4 observed that when moisture is below 1 ppmv, bromine from HBr is not incorporated beyond the native oxide of 316L stainless steel and no macroscopic degradation of the metal occurs. ​ Fine and coworkers confirmed the latter observations by investigating the effect of moisture content on the extent of HBr corrosion for 316L electropolished stainless steel. The scanning electron microscopy (SEM) and x-ray emmision spectroscopy (XES) analysis of the exposed sample coupons indicated no effect upon exposure to HBr containing less than 0.5 ppm of moisture. A moisture content of 10 ppm resulted in bromide incorporation and the onset of corrosion. The formation of corrosion pits was noted upon increasing the moisture level in the HBr to 100 ppm. A dense bromide scale was noted at a moisture concentration of 1,000 ppm. Corrosion is typically quantified by techniques such as trace gas analysis, change of surface morphology, particle shedding and leakage. Wang and coworkers estimated the lifetime of EP 316L stainless steel tubing in HCl service, containing 1 ppm of moisture, to be of the order of 2-3 years based on particle shedding due to corrosion. The latter value is in agreement with field experience. The extrapolated lifetime of EP 316L stainless steel tubing at various moisture concentrations is shown in Table I. The extrapolated lifetime is based on the time required to produce 10 particles/scf at a flow rate of 3.531 scfm (100 slpm). Table I Extrapolated Lifetime of 0.25 – in. 316L stainless steel tubing [10 particles/scf at 3.531 scfm (100 slm)]H2O (ppm)Lifetime5170 Days2425 Days12.3 Years0.54.7 Years0.211.6 Years0.123.3 Years A number of maintenance practices are recommended to eliminate the introduction of moisture into the corrosive gas distribution system7. It has been demonstrated that if adequate purge and evacuation procedures are followed to remove corrosive gases (such as HBr), EP 316L stainless steel can be exposed to moist air without diminishing the initial surface quality. However, if the purge and evacuation procedures are not followed, iron and bromine rich crystalline deposits form on the surface. In order to maintain higher purity in corrosive gas service, new materials of construction have been investigated as a possible replacement for 316L stainless steel. One of the materials being investigated is nickel as it is corrosion resistant in aggressive environments. Nickel, however, is also a reactive material, commonly used as a hydrogenation catalyst.  The thermal decomposition characteristics of active specialty gases on various metal surfaces were investigated by Prof. Ohmi and his group at Tohuku University8. The metal surfaces investigated included nickel, oxygen passivated 316L stainless steel, chromium passivated 316L stainless steel, and 316L stainless steel with an electropolished (EP) surface. The thermal decomposition of the active specialty gases was monitored with the aid of a gas chromatograph (GC) and a Fourier Transform Infrared Spectrometer (FTIR). The FTIR was utilized to monitor the specialty gas concentration exiting the test sample (0.25″ diameter, 1 m long 316L stainless steel tubing). In the case of phosphine, 100 ppm of phosphine in argon was passed through the 316L stainless steel tubing at a flow rate of 5 sccm. The nickel sample exhibited a strong catalytic effect on the phosphine decomposition (see Figure 1). The nickel surface reduced the phosphine concentration to undetectable levels at a temperature of 55°C. In contrast, the EP 316L stainless steel sample resulted in complete thermal decomposition of the phosphine gas at 260°C. The chromium passivated 316L stainless steel surface resulted in complete thermal decomposition at 370°C. 316L Stainless Steel Media and Nickel Media in Corrosive Gas Service The purpose of the SEMI document “Test Method for Evaluation of Particle Contribution from Gas System Components Exposed to Corrosive Gas Service” is to provide a test method to compare gas handling components for potential particle generation in corrosive gas service. The document is intended as a practical means of generating performance data for a group of components to be compared in a selection process. A flow chart of the sequence of exposure of gas handling components to corrosive service and the subsequent determination of the particle contribution is shown in Figure 3. The test sequence was used to compare the corrosion resistance of a gas filter assembly employing nickel media and a gas filter assembly employing 316L stainless steel media.

Soil corrosivity is often classified by its resistivity. 0 – 1500 ohm.cm very corrosive 1500 – 2500 ohm.cm corrosive 2500 – 5000 ohm.cm mildly corrosive 5000 – 10000 ohm.cm slightly corrosive > 10000 ohm.cm non-corrosive Experience suggests that there is little likelihood of corrosion of 304 and 316 stainless steel with soil resistivities of 2000 ohm.cm and above if the pH is greater than 4.5 and there is clean drainage and backfill. As with other environments, chloride levels in relation to pitting and crevice corrosion may also influence the performance of stainless steel in soils and where higher chloride levels are anticipated inland or for non-tidal coastal areas or just where a greater degree of confidence is required, type 316 would be preferred. For coastal areas and other situations where a greater degree of resistance may be required, 2205 duplex stainless steel or super duplex stainless steel can be considered. If thought necessary, external protection such as appropriate protective casings or tapes (taking care to ensure an effective overlap to avoid crevice corrosion) may be used. Stainless steel can also be cathodically protected. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)