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At present, most of the water pipes are concealed and pipe wells. If the material selection is wrong, it is likely to cause huge losses. The common water supply materials include stainless steel pipes, copper pipes, galvanized pipes, composite pipes and plastic pipes. Next, we will compare these materials to see which material is the most suitable. Intensity aspect The most used in stainless steel pipe is 304 or 316 stainless steel, which can meet most of the water treatment and transportation requirements. The tensile strength of the 304 stainless steel pipe is 2 times that of the ordinary steel pipe, about 4 times of the copper pipe, and more than the 8-10 times of the plastic pipe. As the strength of the material determines whether the water pipe is firm and reliable, it is also the most important requirement for the water supply of the building. And under the external force impact, the stainless steel pipe will not leak, and the leakage rate of copper pipe and plastic pipe is higher, and it will be easily damaged by construction or two time decoration. Thermal expansion and thermal expansion The thermal expansion coefficient of the stainless steel pipe is about the same as that of the copper pipe, which is 1.5 times that of the ordinary steel pipe, and the heat expansion and cold shrinkage of the stainless steel pipe is still relatively slow. The expansion coefficient of the plastic pipe is too large, which is fatal and is not suitable to be used as a heat pipe. Under the condition of environmental temperature change, the plastic pipe can also easily produce the hidden danger of leakage and so on, especially in the concealed engineering. The composite pipe has two different kinds of material expansion coefficient, which causes the joint to crack easily, which makes the pipe easier to burst. The thermal conductivity of stainless steel pipe is 1/25 of copper pipe, 1/4 of ordinary steel pipe, very suitable for hot water transportation, and the thermal insulation performance is much better than copper pipe. Corrosion resistance One of the best advantages of stainless steel pipes is the excellent corrosion resistance, which is the best of the five pipes. Because the stainless steel will produce passivation and oxidant to form a layer of dense tenacity the chromium oxide protective film on the surface of Cr2O3, can effectively prevent further oxidation reaction. Other metal pipes are far from stainless steel in corrosion resistance. Health and environmental protection performance The sanitary properties of stainless steel pipes are excellent, which can ensure that the water quality does not have all kinds of strange problems, nor does it smell or foul. It does not precipitate harmful substances, ensure the purity of the water, and is healthy and harmless to the human body. Stainless steel pipe not only in the food industry including beverages, dairy products, brewing, pharmaceutical industry, and other industries and long-term use of tableware cookware has become standard timber in these industries, but also a large number of materials used in the safety and cleanliness requirements of high medical body implants such as various stents, artificial joints and steel nail body, and become a standard material requirements for cleanliness of clean room of semiconductor industry’s extreme. Therefore, with the continuous improvement of water quality and the strict regulation of regulations on hazardous substances in water pipes, stainless steel pipes become the best choice for transporting high-quality water. Price Although the price of stainless steel pipe is higher than that of other pipes, it is very limited, but the material performance is much superior, and it also greatly improves the grade of the pipe. In fact, the selection of stainless steel water pipes is much more than initial investment, but the life cycle cost is very low, which is the absolute advantage of stainless steel compared with other materials in terms of economy. Source: China Stainless Steel Pipelines Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

When chromium – nickel austenitic stainless steel is heated to the temperature range of 450-800 C, corrosion often occurs along the grain boundary, which is called intergranular corrosion. Generally speaking, intergranular corrosion is actually carbon element precipitated from Cr23C6 in the metallographic structure of saturated austenite, resulting in poor austenite structure at grain boundaries. Therefore, it is an effective way to prevent chromium poor from grain boundary to prevent intergranular corrosion. The elements in stainless steel are sorted according to the affinity of carbon affinity, and the order is titanium, niobium, molybdenum, chromium and manganese. It can be seen that the affinity between titanium and carbon is greater than that of chromium. When titanium is added to steel, carbon will give priority to titanium bonding to form titanium carbide, which can effectively prevent the formation of chromium carbide and precipitation, resulting in grain boundary chromium depletion, which can effectively prevent intergranular corrosion. Because titanium and nitrogen can combine to form titanium nitride, titanium and oxygen can form titanium dioxide. Therefore, the amount of titanium added is limited. In order to avoid intergranular corrosion in the actual stainless steel production, the amount of titanium is mainly about 0.8%. In order to avoid intergranular corrosion, stabilization treatment must be made after solid solution treatment of titanium containing stainless steel. After solution treatment of austenitic stainless steel for single-phase austenite, but the state is not stable, when the temperature is raised to more than 450 DEG C, solid solution of carbon in the form of carbide precipitation will gradually, of which the formation of Cr23C6 temperature is 650 degrees Celsius, 900 degrees is the formation temperature of TiC. To avoid intergranular corrosion, the Cr23C6 content is reduced, so that the carbide is completely in the form of TiC. Because the stability of titanium carbide is higher than that of chromium carbide. When the stainless steel is heated to 700 degrees, the carbide of chromium will start to transform to titanium carbide. Stabilization treatment is to heat the stainless steel to 850-930 degrees, and to keep it for 1 hours. At this time, chromium carbide will be completely decomposed to form stable gray or black titanium carbide, and the intergranular corrosion resistance of stainless steel can be optimized. In addition, the addition of titanium in stainless steel can also diffuse and precipitate Fe2Ti intermetallic compounds to improve the high temperature strength of stainless steel under certain conditions. However, titanium is not completely harmless in stainless steel, and sometimes titanium will also harm the properties of stainless steel. For example, TiO2 and TiN are their high content of inclusions, and uneven distribution, to a certain extent, reduce the purity of stainless steel will make the surface quality of stainless steel ingot; the variation of grinding process leads to increased, it is easy to cause waste; the polishing performance of the finished product is not very good, very high processing difficulty and high precision surface the. Source: China Stainless Steel Flanges Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

There are many ways to connect the stainless steel pipe fittings, the main ones are the pressure-type connection, the ring pressure connection, the flange connection, the groove connection, the welding connection and the taper thread connection. They are both good and bad, and in practice they need to find the best way. Compression coupling The connection principle of this method is to use the hydraulic clamp to clamp the stainless steel pipe fitting on the pipe, and to achieve the stop water effect with O ring seal, thus having the connection effect. Although this way is simple, but the wall is thin, only too low connection strength to around a third of the pipe body and pipe cannot remove, stainless steel pipe port burr, flash removal without clean easily damaged aprons, easy to leak in the future. Ring pressure connection The principle of ring pressure connection is to use hydraulic forceps to tighten the stainless steel pipe fitting on the pipe, and to stop the water with the wideband rubber sealing ring to achieve a good connection effect. Because this way more than the viega profi-press a pit, so is slightly stronger than the viega profi-press connection strength, moreover is pit due to the ring type, so easy to turn the pipe, it will affect the sealing effect of the whole. Flange connection The method principle of flange connection is to use tightening bolts to connect two connecting pieces with flange pieces, then the corresponding connection effect can be achieved by sealing the plane seal. The advantage is that the connection strength is high quality and stable, easy to install and detachable, but the disadvantage is that the cost of flanges is high. Groove connection The principle of this method is to use a tight fitting nut, the expansion of a convex ring of stainless steel pipe and tube axial compression, and then through a conical seal water effect, so as to achieve a wireless connection. The advantage is removable, the disadvantage is that the installation process increases the process of pipe end rolling ring, the casting cost is high, and can not be used in the pipeline with negative pressure. Welding connection The connection principle of this method is to weld the two connectors directly through the hot melt process to reach the connection. Its advantage is high bonding strength, but the disadvantage is that the scene the seam gas protection welding at the mouth of the hard to improve, weld easy to rust, this will reduce the service life of pipeline, and installation quality to a large extent depends on the welding technology, so the stability of the quality is not high. Taper thread connection Is directly to tighten the connection principle of stainless steel pipe fittings, the tapered pipe thread with two fittings tighten internal and external interface to connect mouth thread pressure to achieve sealing effect, so as to complete the connection. Its advantage is easy to remove, joint strength reached the strength of pipe body, simple installation and easy, quality reliable, stable, and the pipe wall thin leads to lower costs, in addition if the external thread interface ptfe teflon tape, need strength, but if you use liquid ribbons, is basic guarantee interface does not leak for a long time. Source: China Stainless Steel Pipe Fittings Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

During the process of solid solution treatment, stainless steel pipes need to pay attention to the influence of protective atmosphere, temperature and cooling speed. The first is the light online solution treatment procedures, stainless steel pipe in the production process caused by rolling, drawing and welding heat effect, will lead to pipe structure and mechanical property will have no small change, will affect the quality of the stainless steel pipe to serious, changes may occur mainly cold hardening the phenomenon, it refers to the regular fault of a column or several columns appear atomic microstructure crystal lattice distortion, which, as a significant stress concentration zone, this phenomenon is also called dislocation. This is because of high temperature and uneven cooling will generate welding stress and the formation of ferrite in the original single austenite, carbide produced uneven organization, in order to increase the processing efficiency, ensure that the stainless steel pipe surface light level standards, to remove residual stress, single austenite microstructure and high quality stainless steel pipe, it must to take the online light solution treatment method. The second is to protect the atmosphere, light online solution treatment is usually used as a protective atmosphere gas ammonia decomposition, ammonia at 400 ℃ will be decomposed into hydrogen and nitrogen, hydrogen is a reducing gas to restore some metal in the corresponding conditions, nitrogen is neutral gas. Using the liquid ammonia decomposition atmosphere as a protective gas, it can make the surface of the stainless steel pipe smooth and bright, so it is also the most cost-effective and effective protection gas. In addition, the need to pay attention to the solution temperature, because it is one of the most important parameters in the process of solid-liquid processing, high or low temperature will directly affect the quality of the products of stainless steel pipe, high temperature will make the stainless steel pipe microstructure coarsening, reduced performance, low temperature will not dissolve completely, can not completely eliminate stress so, need the appropriate temperature and appropriate insulation, so as to fully dissolve carbide. The effect of cooling rate should also be paid attention to in the later period of solution treatment. For austenitic stainless steel at 650 ℃ -850 ℃ interval, brittle phase may be occurred, in general is a form of needle flake in the austenite grain or grain boundary, will greatly plasticity, toughness and strength of the material decreases at 450 ℃ -850 ℃ interval is austenitic stainless steel intergranular corrosion in sensitive areas. The metal grain temperature range in the supersaturated solid solution of carbon atoms to grain edge diffusion, and edge layer of chromium carbide formation, and along the grain boundaries, which makes the grain edge because of poor chromium and loss of corrosion resistance, the austenitic stainless steel is heated to 1080 ℃ + 10 ℃, usually insulation, stainless steel the carbide can be fully dissolved, followed by rapid cooling, to prevent stainless steel at 450 ℃ -850 ℃ interval to stay, so not only can avoid phase sigma intergranular corrosion, also won’t let carbide Precipitation along austenite grain boundary can directly get the uniform saturated single austenite metallographic structure, so as to perfect the stainless steel pipe online bright solution treatment. Source: China Stainless Steel Pipes Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Because the passivation of the stainless steel plate occurs in the oxidizing medium, the corrosion resistance in the general sense refers to the corrosion resistance of the oxidizing medium. While in the non oxidative acid environment, such as sulfuric acid and strong acid, the conventional chromium stainless steel and chromium nickel stainless steel are not corrosive, especially in the medium containing chloride ions in the environment, because the passivation film of chloride ion can destroy the stainless steel board, leading to local formation of corrosion, that is the point corrosion. Is there no way for stainless steel plates to corrode the non oxidizing medium? The answer is, it is proved by experiments and practical use that adding molybdenum and copper to stainless steel can effectively improve the corrosion resistance of stainless steel in the non oxidizing medium. Molybdenum can make the stainless steel surface passivation reaction, can effectively improve the performance of stainless steel pitting corrosion and crevice corrosion in ferritic stainless steel, if does not contain molybdenum, chromium content high is not satisfactory pitting ability, but only in the chromium stainless steel adding molybdenum elements can play a role. Generally, the higher the chromium content, the better the corrosion resistance of the molybdenum reinforced stainless steel. The practice shows that the ability of molybdenum to improve the corrosion resistance of stainless steel is basically three times that of the chromium element. Adding 1% of the molybdenum element in 1Cr17 stainless steel can significantly improve the corrosion resistance of organic acids and hydrochloric acid. Adding 1.5-4.0% molybdenum element in 18-8 chromium nickel stainless steel can increase the corrosion resistance of stainless steel plate in dilute sulfuric acid, organic acid, hydrogen sulfide or sea water. Molybdenum is an element to form ferrite. Therefore, the addition of molybdenum to 18-8 chromium nickel stainless steel ensures that the pure nickel content of austenite must also be improved. After adding the molybdenum element, the nickel content of 18-8 stainless steel usually increases to 12%. Molybdenum can also improve the mechanical properties of austenitic stainless steel at high temperature. Adding 0.5%-4.0% molybdenum element in martensitic stainless steel can also improve the tempering stability of stainless steel. Molybdenum can also precipitate precipitates in stainless steel and increase the strength of stainless steel. Adding copper to stainless steel can improve the corrosion resistance of stainless steel in the sulfuric acid environment. The molten steel of copper containing stainless steel is more fluidity and is easier to be cast as a better quality component. Copper can also enhance the cold working performance of stainless steel. Source: China Stainless Steel Plate Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The deformation resistance of the stainless steel plate is very high. It is very easy to stick to the mould when drawing the stainless steel plate, which leads to the scratch on the stainless steel plate. In order to ensure that the drawing process can be carried out smoothly, it is necessary to make proper surface treatment for stainless steel plates, including surface oxide coating and surface coating. The composition of the oxide sheet on the surface of the stainless steel plate is very complex, which is influenced by the alloy elements in the stainless steel composition. Therefore, it is necessary to understand the properties of the common elements and their oxides in the stainless steel plate. According to the order of influence from large to small, chromium and its oxides and chromium metals are stable in nitric acid, alkali, carbonate solution and organic acid, but they are easy to dissolve in hydrochloric acid and hot concentrated sulfuric acid. The common chrome oxide mainly include chromium oxide, chromium oxide and chromium oxide chromium oxide three, which is very unstable in the air will be oxidized to form Cr2O3. Chromic oxide is a kind of green insoluble material, basically insoluble in acid solution. Three chromium oxide is chromic anhydride can dissolve in sulfuric acid and nitric acid solution. In addition to nickel and its oxides, nickel metals are basically insoluble in sulfuric acid and hydrochloric acid, only in nitric acid. The oxide of nickel mainly consists of two kinds of nickel oxide and three oxidation of two nickel. The former is dissolved in hydrochloric acid and sulfuric acid, and the latter is very dense and insoluble in sulphuric acid. Then, manganese and its oxide, manganese metal can be dissolved in acid, manganese oxide more common, there are MnO, Mn2O3, MnO2, Mn3O4, Mn2O7. Low valence oxide is alkaline, manganese dioxide is two, and high valence oxide is anhydride. Because the oxide skin on the surface of the stainless steel plate is a low price manganese, it can be dissolved in acid. The oxide of silicon is mainly silica, which can only act with hydrofluoric acid, and it will dissolve in hot alkali solution to form the corresponding silicate. The alloy element molybdenum in stainless steel does not interact with hydrochloric acid and dilute sulfuric acid, but it will only be dissolved in nitric acid and hot sulfuric acid. The oxide is MoO3, it can dissolve in acid and alkali. Titanium is always stable at room temperature and can resist corrosion. It is easy to form compounds with oxygen and nitrogen at high temperature, namely titanium dioxide and titanium nitride. The former will be dissolved in sulfuric acid and alkali. Stainless steel plate surface oxidation in the skin of main component of chromic oxide and nickel oxide form they are chrome spinel and nickel spinel. The oxide scale is dense and thin, and is firmly combined with stainless steel substrate. It is difficult to remove simple acid pickling. It is usually removed with alkali leaching and mixed acid washing. Source: China Stainless Steel Plate Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The removal of the surface oxide of stainless steel plate is to soak the material in alkaline molten salt or solution, which is called alkaline leaching, and alkali leaching is pided into two types: molten salt and solution alkali leaching. The molten salt is made up of alkali metal or alkaline earth metal hydroxide or carbonate and oxidant, commonly used antioxidants including sodium peroxide, nitrate, potassium permanganate, borax and dichromate, etc. Molten salt leaching process is to put the stainless steel plate is placed in an alkaline solution of molten corresponding time rapid quenching after soaking in water, the action principle of this method is mainly have two aspects, one is stainless steel plate expansion coefficient of metal oxide coating and the magnesium substrate have distinction, scale of plasticity is lower, stainless steel plate in the quenching water will cause the scale burst or fall off; The second is that some components of the oxide skin, such as MoO3, SiO2, Al2O3 and TiO2, will be dissolved in alkaline solution, and Cr2O3 will also act with molten salt to form high price chromate. As part of the skin of the stainless steel plate is dissolved and the high price of chromium salt is produced, it will loosen the skin and be easily dissected in the subsequent pickling. Molten salt to remove oxide skin has the advantage of not etching stainless steel substrate, nor cause acid hydrogen embrittlement, due to the strong alkali molten salt oxidizing, alkali leaching can skim and remove the stainless steel panel black ash, moreover the alkali leaching as long as according to the proportion of added regularly molten salt, alkali leaching processing can continue. But need to pay attention to in alkali leaching operation into the base groove stainless steel plate must be kept dry, can not with water, or it will lead to explosion, stainless steel plate also must be completely immersed in the molten salt, alkali leaching after rapid quenching water quenching is completed in a timely manner to clean water, remove residual alkali on the surface of the stainless steel plate, avoid stainless steel plate by alkali corrosion. Molten alkali trough in the application after a period of time, the bottom of the channel will deposit base mud, stainless steel plate in the alkaline mud not by alkaline process, will form in the pickling local scale couldn’t remove defects, so be sure to get rid of precipitation alkaline mud on a regular basis. In alkali leaching operation, need to pay attention to some stainless steel materials, such as precipitation hardening stainless steel and high chromium iron ferrite stainless steel, during 450-600 ℃ for alkali Baptist abate material of plastic, need to strictly control the temperature and time. Principle and molten salt leaching solution of alkali leaching, alkaline leaching and acid pickling solution, can significantly reduce the time to remove the oxide of the stainless steel plate, the technological process is acid, water washing, alkali leaching solution, water washing and three pickling. Source: China Stainless Steel Plate Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

In various practical applications, the thickness of stainless steel water pipes will not be exactly the same. There are many factors that influence the adjustment of wall thickness, such as mechanics, corrosion resistance, wear resistance, economy, connection mode and so on. This is a detailed analysis of these factors. First, the effects of material mechanics, corrosion resistance and wear resistance are observed. Because stainless steel is recognized as the three excellent metal materials. The tensile strength of stainless steel pipe made of 304 stainless steel is more than 520Mpa, the surface of thin and dense oxide film of chromium also make stainless steel pipe in all water has excellent corrosion resistance, and can withstand a long time erosion of high-speed water flow, in addition to thick wall stainless steel pipe can fully meet the above 50 year service life. The second aspect connection of stainless steel pipe, the main traditional welding flange and so on, but due to the characteristics of their installation process, also decided to use only the thick wall stainless steel pipe, stainless steel pipe to ensure the connection strength and reliability of welding, usually require stainless steel tube wall thickness is greater than 2.0mm. The connection of other popular thin-walled stainless steel tubes is a unique design structure for pipe fittings. The third aspect is from the economic point of view. In some sense, of course, it is thicker stainless steel pipe with thicker wall thickness, which ensures the safety and reliability of the pipeline system. However, because the price of stainless steel material is more expensive, the increase of wall thickness will certainly increase the cost of the pipeline system. In terms of the user’s economic requirements, it is possible to use the wall thickness as long as it can meet the requirements of the service life. According to the experience of stainless steel pipe in European and American countries, the 0.8mm thick wall stainless steel pipe specified in the industry standard can meet the requirement of 50 years’ service life. As for the thin-walled stainless steel pipe, the thickness of the pipe is the key to the connection strength of the pipe. When the wall thickness is reduced to the safety factor, the reliability will certainly be reduced by several levels. The essence of the stainless steel pipe wall thickness is a surface, which essentially requires not only ensure the strength of pipeline connection, but also have good performance of external force collision resistant to various kinds of seismic performance, under various circumstances, and hidden works for the life of the product and corrosion allowance. The wall thickness of stainless steel pipes specified in the ASTM standard is a lot of calculation and practice. On the basis of many years experience of European and American countries, it is determined by referring to the advanced foreign standards. Therefore, it is possible to confirm that the wall thickness specified in the standard is suitable. Source: China Stainless Steel Water Pipe Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The oxide film on stainless steel plate is actually a five color transparent film. Its color change is influenced by the interference principle of light. What color does it appear in the light interference, mainly caused by the thickness change of oxide film on the stainless steel plate surface. Therefore, the oxidation resistance of the stainless steel plate is the most effective method to solve the high temperature discoloration of the stainless steel. The factors that affect the oxidation resistance of stainless steel are mainly chemical elements, the influence of oxide film and the influence of surface roughness. The first is the chemical elements, carbon content in stainless steel is low in the high temperature environment of carbon atoms in the oxidation process is easy to spread to the inside organization of stainless steel substrate, so the oxidation process of stainless steel plate with carburizing process, test chromium, silicon and nickel content of different types of stainless steel high-temperature cycle test. After the test, the ratio of carbon content in the stainless steel is measured, and the degree of oxidation of the stainless steel is determined by the carburizing amount. In order to further verify the effect of silicon on the carburizing resistance of stainless steel, the proportion of silicon element in 310S stainless steel should be adjusted, followed by high-temperature cycling test. The final test results show that the high temperature oxidation resistance of stainless steel plate has been significantly improved when the mass fraction of chromium is increased to 22% or the mass fraction of silicon is more than 2%. The effect of the oxide film on the oxidation resistance of the stainless steel plate is also seen. The tough oxide film on the stainless steel plate can prevent the oxidant from invading the stainless steel, that is to prevent the oxidation from continuing to produce, while the loose oxide film will make the oxide film continue to thicken. In continuous production line, a continuous acid washing method is used to make forced oxidation of the stainless steel plate to enhance the density of the oxide film on the stainless steel plate. The last is the influence of the surface roughness of the stainless steel plate, and the oxidation of the surface of the stainless steel plate will be thickened by the oxidation of the surface in the high temperature environment. There is a direct link between the material and its oxidation resistance and heat absorption capacity of stainless steel material, surface roughness, surface color of stainless steel plate will affect the heat absorption unit area and the influence degree of discoloration of stainless steel. The practice shows that when the surface roughness of BA stainless steel plate is below 0.022 m, the endothermic capability of stainless steel decreases obviously, and the stainless steel will not oxidize further. The thickness of oxide film is basically unchanged under high temperature, and the degree of discoloration is also very slight. Source: China Stainless Steel Plate Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

The normal working temperature of the heat exchanger is greater than 200 degrees, but sometimes the stainless steel bolts are easy to rust. The reason is that at high temperature, the thermal cycle will lead to some stainless steel models becoming non stainless steel. Therefore, stainless steel fastener materials must be chosen with caution. Contrary to general cognition, stainless steel will not remain stable forever. For example, the thermal cycle mentioned earlier will lead to chromium content in some stainless steel, which is reduced to rust prone level. Therefore, in the specific application scene, we should choose the stainless steel model which can meet the special needs of the scene. So, for stainless steel fasteners, what are the types of stainless steel that are suitable for use? First, the next 300 series of stainless steel, of which 18-8 stainless steel, are the most commonly used materials for fasteners, joints, pipes and pipes. This type of stainless steel has excellent corrosion resistance, but when heated to 200 degrees, the chromium content will be reduced because of the deposition effect of carbon. Chromium and carbon will generate chromium carbide at high temperature, which is not rust free. 304L and 321 stainless steel can alleviate this problem. In the ordinary environment, the above models of stainless steel can be used as fasteners. Let’s look at the next 400 series stainless steel, while the chromium content of stainless steel in less than 300 series stainless steel, but there is no carbon deposition problem is similar to that of 300 lines, and also used for heat treatment, indicating that the 400 series stainless steel can be used in operating temperature up to 400 degrees Celsius in the environment. However, the chromium content in the stainless steel is only about 12%-14%, and it will still be corroded in a serious chemical atmosphere. The 300 series stainless steel contains chromium elements of 16%-20%, but it will not be corroded. The strength of the 300 – line stainless steel and the 400 – system stainless steel is the same. In general, 410, 416 and 430 stainless steel are suitable for fasteners in 400 series stainless steel. Here are some special stainless steel, such as A-286 stainless steel, which is the most widely used in aerospace industry. It belongs to iron-based stainless steel. It contains 15% chromium, heat treatment and cold hardening. Basically, all aerospace industry fasteners can provide A-286 fasteners. There are also MP35N and MPl59, which are two very good materials in high temperature and high corrosive environments, containing 19% chromium. But their prices are high even in the space industry. This material is usually used only when there is no other choice, because the output is not high, except the price is very expensive. Generally speaking, if the working temperature is not high and the environment corrosion is serious, fasteners made of 300 series stainless steel can be used. If the strength requirement is high, but the environmental corrosion is not serious, the 400 series stainless steel can be used. A-286 stainless steel fasteners can be used if the 300 and 400 series stainless steels are not applicable. Source: China Stainless Steel Fasteners Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel fastener standard parts are made of stainless steel wire as raw material, and then processed according to the related working procedure of pier. At present, stainless steel fasteners have been widely used, because the performance advantages of their various aspects are very obvious. Below are the advantages of these fasteners. The first is the high temperature resistance of stainless steel fasteners. Because of its hardness and anti oxidation ability of stainless steel fasteners made of very strong, have high antioxidant properties, and also can work under high temperature, and will not suffer too much influence in high temperature environment, even if the stainless steel fasteners and passivation after manufacturing, the high temperature performance will be better. Stainless steel fasteners have high resistivity. Specifically, the resistivity of stainless steel fasteners is five times higher than that of carbon steel. The test shows that the higher the temperature is, the expansion coefficient of the stainless steel fastener will be improved to a certain extent. The capacity of stainless steel fasteners to withstand load is relatively moderate, though it can not be compared with high-strength bolts, but it is also enough to meet daily needs, and its price is much cheaper. The mechanical properties of stainless steel fasteners are mainly influenced by the mechanical properties of the stainless steel wires used, such as hard rust and strong corrosion resistance. And with the rapid development of stainless steel materials, the mechanical properties of stainless steel fasteners will become stronger and stronger. In the selection of fasteners, stainless steel material has no magnetism in fact does not show that its quality is good or bad, actually some Cr Mn stainless steel is also not magnetic, and austenitic stainless steel after certain processing technology, it may produce a certain magnetism, so to have no magnetic to judge the quality of stainless steel fasteners is not accurate. Stainless steel fastener material Cr Mn stainless steel can not replace the 300 series stainless steel fasteners, especially when the working environment is highly corrosive. In general, whether in manufacturing, application or processing, fasteners are made of stainless steel as raw materials are of considerable advantage, although the relatively high cost of stainless steel materials, but its use is actually longer cycle, fastener materials in many environments, is actually very cost-effective. Source: China Stainless Steel Fasteners Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

There are many available to make the fasteners material, which are made of stainless steel fasteners not only the appearance of texture better, higher strength and better corrosion resistance, which can also better machining and welding, and stainless steel fasteners can be electroplated or heat treatment, in order to obtain higher performance, in addition to be 100% recycled use. In the selection of the type of timber fasteners stainless steel, stainless steel is not a magnetic model can’t be judged as the material performance level of reference, because of the many types of stainless steel materials, stainless steel is actually not part of Cr Mn magnetic, but this kind of stainless steel and 300 austenitic stainless steel, the traditional non magnetic stainless steel performance is very large compared to the gap. So when judging the quality of stainless steel fasteners, need to distinguish between material types. In addition, the magnetic properties of stainless steel are not static. For example, the austenitic stainless steel itself, which is magnetically free, may produce some magnetism after being processed by some processes, but this austenitic stainless steel can also be used to make stainless steel fasteners with high quality. Ordinary stainless steel fasteners can be used in most of the daily working environment, but in some high temperature and high corrosive environments, special attention should be paid to stainless steel fasteners for stainless steel material selection. In addition, the use of nickel in stainless steel fasteners is also a matter of concern. In the past, when stainless steel was selected for fasteners, the performance of stainless steel was heavily dependent on nickel. However, with the rising nickel price, the price of stainless steel was also high, which also affected the price of stainless steel fasteners. Therefore, in order to save production costs, stainless steel fasteners manufacturers actively seek alternatives to nickel in stainless steel, and also consider that they will not affect the performance of stainless steel fasteners. To sum up, the selection of stainless steel fasteners is a comprehensive consideration. We should seek a balance in the relatively expensive stainless steel prices and performance, which is not only conducive to the production enterprises, but also conducive to users. Source: China Stainless Steel Fasteners Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)