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In engineering, that is, fundamentally solve the problem of precipitation of chromium carbide (crc) on the grain boundary. Generally, the requirement of intergranular corrosion resistance can be met when the amount of carbon in steel is reduced to less than .%.When installing and welding the fixed port of stainless steel pipe, and some sides are easy to be blocked. In this case, water-soluble paper + blocking plate can be used for blocking. That is, the easy to vent and good side can be blocked with blocking plate, the difficult to vent and bad blocking plate side can be blocked with water-soluble paper, and the weld on the outer side can be blocked with adhesive tape (see Table ) .Ayia Paraskevi,Allowable depth of straight track: hot rolled and hot-rolled steel pipes with diameter less than or equal to mm shall not be greater than % of the nominal wall thickness, the atmospheric corrosion resistance of steel increases significantly and the large depth shall not be greater than .mm.When the addition of chromium reaches %, but when the chromium content is higher, although the corrosion resistance can still be improved, it is not obvious. The reason is that when alloying steel with chromium, the type of surface oxide is changed to be similar to that formed on pure chromium metal. This tightly adhered chromium rich oxide protects the surface from further oxidation. This oxide layer is very thin. Through it, you can see the natural luster of the steel surface, which makes the stainless steel have a unique surface. Moreover, if the surface layer is damaged, the steel surface will react with the atmosphere to repair itself, re form this passive film and continue its protective effect.Zakho,Austenitic stainless steel has good resistance to uniform corrosion, but there are still the following problems in local corrosion resistance: intergranular corrosion of austenitic stainless steel. Austenitic stainless steel will have intergranular corrosion when it is kept warm at ~ ℃ or cooled slowly. The higher the carbon content, the greater the tendency of intergranular corrosion. In addition, intergranular corrosion also occurs in the heat affected zone of the weldment. This is due to the precipitation of Cr rich CrC on the grain boundary. The chromium poor area is formed in the surrounding matrix, which is caused by corrosion of the primary cell. This intergranular corrosion phenomenon also exists in the ferritic stainless steel mentioned above.At low temperature, ferritic stainless steel pipe has low-temperature brittleness like carbon steel, but austenitic steel does not. Therefore, ferritic or martensitic stainless steel produces low-temperature brittleness, while austenitic stainless steel or nickel base alloy does not show low-temperature brittleness. Sus (Cr) and SUS (cr) of ferritic stainless steel pipe It shows that the impact value decreases sharply at low temperature. Therefore, it is necessary to pay special attention when using at low temperature. As a way to improve the impact toughness of ferritic series stainless steel, the embrittlement temperature is in the range of - ℃ to - ℃Hardness test: annealed stainless steel pipes with inner diameter of more than mm and wall thickness of less than mm can be tested by w-b Vickers hardness tester, which is very fast and simple, and is suitable for rapid and nondestructive qualification test of stainless steel pipes. For stainless steel pipes with inner diameter of more than mm and wall thickness of more than mm Rockwell hardness tester shall be used to test HRC hardness. Stainless steel pipes For stainless steel pipes with inner diameter greater than mm and wall thickness less than mm, the surface Rockwell hardness tester shall be used to test HRT or hrn hardness. For stainless steel pipes with inner diameter less than mm and greater than mm, the special Rockwell hardness tester for pipes shall be used to test hrt hardness. When the inner diameter of stainless steel pipes is greater than mm, the Rockwell or surface Rockwell hardness tester can also be used to test the hardness of pipes.

Stainless steel pipe factory stainless steel products are widely used in hardware products, furniture, mechanical structure, mechanical accessories, precision medical instruments, fluid transmission pipelines, such as furniture, machinery, medical oil, natural gas, water, gas, steam and other industries.Surface feature surface feature manufacturing method summary application silver white matte hot rolled to the specified thickness, and then annealed and descaled. A rough and matte surface does not need surface gloss. Silver white cold rolled heat treatment and pickling D products are used for applications with lax surface requirements. Generally the gloss of deep drawing materials is stronger than that of D treatment, After finishing a light cold rolling with polishing roller, the general material Ba is as bright as a mirror. There is no standard, but it is usually the surface processing of bright annealing,Ayia ParaskeviStainless steel plate perforated mesh plate, and the surface reflectance is very high. For building materials, ~ # (unit) abrasive belt is used for kitchen coarse grinding to grind building materials, stainless steel coil and stainless steel belt, Stainless steel pipe quality assurance. New and old customers are welcome to consult during the preferential activities. HL hair line grinding in the kitchen is carried out by grinding materials with appropriate particle size for hair line grinding ( ~ #). There are many buildings and building materials close to mirror grinding. # rotary polishing wheel is used for grinding for art, mirror grinding for mirror, and polishing wheel is used for grinding reflector, For decoration, according to the purpose, bridge steel plate boiler steel plate, shipbuilding steel plate, armored steel plate, automobile steel plate, roof steel plate, structural steel plate, electrical steel plate (silicon steel sheet), spring steel plate, special solar plate (Hairui special steel) are common Japanese brands in other steel plates for ordinary and mechanical structures.Proper heat treatment process can prevent intergranular corrosion and obtain excellent corrosion resistance.Superior quality,Austenitic stainless steel has good resistance to uniform corrosion, but there are still the following problems in local corrosion resistance: intergranular corrosion of austenitic stainless steel. Austenitic stainless steel will have intergranular corrosion when it is kept warm at ~ ℃ or cooled slowly. The higher the carbon content, the greater the tendency of intergranular corrosion. In addition, intergranular corrosion also occurs in the heat affected zone of the weldment. This is due to the precipitation of Cr rich CrC on the grain boundary. The chromium poor area is formed in the surrounding matrix, which is caused by corrosion of the primary cell. This intergranular corrosion phenomenon also exists in the ferritic stainless steel mentioned above.CE--“ Code for design of cold formed stainless steel structural parts & rdquo; And & ldquo; jointly published by nidi and euro inox; Structural stainless steel design manual & rdquo; The design of structural parts for buildings with long service life and good integrity has been simplified.Therefore,Ayia Paraskevi20 stainless steel welded pipe, there are requirements for the service environment of stainless steel, and it is necessary to remove dust frequently and keep it clean and dry.

At the same time, the Ministry of construction attaches great importance to the application of stainless steel pipes. The industry standard of stainless steel water pipe was issued and implemented in . The Ministry of construction has issued documents on relevant technical specifications and installation sets of pipeline engineering, which are being prepared by Tongji University. All kinds of stainless steel plate, stainless steel coil, there are stainless steel pipes in Sichuan, Guangdong, Zhejiang, Jiangsu and other places, and the products have become mature. Therefore, the time for application has come.production costs, the responsibility of the calender is that the annealed steel strip is blackened, the furnace liner is perforated, and ammonia leakage will cause rust. . The responsibility of the steel plant is that the peeling and trachoma of the steel strip will cause rust. Substandard materials will cause rust. the responsibility of the calender is that the annealed steel strip is blackened, the furnace liner is perforated, and ammonia leakage will cause rust. . The responsibility of the pipe manufacturer: the welds in the pipe manufacturer are polished rough,Ayia ParaskeviWhich is a good stainless steel pipe, which will cause rust.According to different metallographic structure of stainless steel, it is divided into semi Ferritic and semi martensitic stainless steel pipe, martensitic stainless steel pipe, austenitic ferritic stainless steel pipe, etc.Stainless steel pipe is a kind of hollow long round steel, which is widely used in industrial transmission pipelines such as petroleum, chemical industry, medical treatment, food light industry, mechanical instruments and mechanical structural parts. In addition, when the bending and torsional strength are the same, the weight is relatively light. It provides L stainless steel pipe, s stainless steel pipe and L stainless steel pipe for a long time. It is an old brand of , with advantages in price and guaranteed quality It is also widely used in manufacturing mechanical parts and engineering structures. It is also commonly used as furniture, kitchenware, etc.Ayia Paraskevi,Stress relief treatment. Stress relief treatment is a heat treatment process to eliminate the residual stress of steel after cold working or welding. It is generally heated to ~ ℃ for tempering. For steels without stabilizing elements Ti and Nb, the heating temperature shall not exceed ℃, so as to avoid intergranular corrosion caused by chromium carbide precipitation. For cold worked and welded parts of ultra-low carbon and stainless steel containing Ti and Nb, they need to be heated at ~ ℃ and then cooled slowly to eliminate stress (the upper limit temperature is taken for eliminating welding stress), which can reduce the tendency of intergranular corrosion and improve the stress corrosion resistance of steel.There shall be a special storage rack. The storage rack shall be a wooden or painted carbon steel support or padded with rubber pad to isolate it from carbon steel and other metal materials. During storage, the storage position shall be convenient for lifting and absolutely isolated from other data storage areas. Protective measures shall be taken to avoid purification, collision with other components, purification and damage of iron metal.Production process of stainless steel pipe A. preparation of round steel; b. Heating; c. Hot rolling perforation; d. Cutting head; e. Pickling; f. Grinding; g．； h. Cold rolling; i. Degreasing; j. Solution heat treatment; k. Straightening; l. Pipe cutting; m. Pickling; n. Finished product inspection.