SS 201/304 Stainless Welded Steel Tube

                                     SS 201/304 Stainless Welded Steel Tube

Stainless Steel is the abbreviation of stainless and acid-resistant steel, it is resistant to air, steam, water and other weak corrosive media or stainless steel, such as 201 (1Cr17Mn6Ni5N), 202, etc. 2 series of steel; and will be resistant to corrosion of chemical corrosive media (acids, alkalis, salts, etc.) corrosion of the steel become acid-resistant, such as 304 (06Cr19Ni10), 316 (0Cr17Ni12Mo2), etc. 3 series of steel. ) and other 3 series of steel. Because of the differences in chemical composition of the two resulting in their ability to resist corrosion is different, like 2 series of Stainless Steel Pipe is generally not resistant to corrosion of chemical media, and 3 series of stainless steel have the ability to resist corrosion of chemical media.

The common labelling methods on the market are chemical (06Cr19Ni10), SUS (SUS304), of which 06Cr19Ni10 generally indicates that the national standard production, 304 generally indicates that the U.S. ASTM standard production, SUS 304 indicates that the Japanese standard production.

Of course, stainless steel is not completely will not rust, just relative to ordinary steel has more excellent corrosion resistance, even if the same stainless steel corrosion resistance is also a big difference, like 2 series and 3 series is very obvious

. Sometimes we get a material in the absence of a long time before the environmental test is difficult to distinguish between the material is 2 series or 3 series, there are many testing methods on the market, briefly introduce two relatively simple methods, one is to look at the appearance of the 201 as a representative of the 2 series contains a high degree of carbon and manganese, the surface will be relatively dark even if polished will also be processed black bright colours; the second is to look at the cutting spark, the 201 material is relatively hard when cutting Sparks will be more not larger.

On the contrary, the 3 series, represented by 304, will be brighter, with a relatively softer texture cutting much less spark.

Stainless steel and our lives are closely related, the largest amount of 201 and 304, 316 quality to be higher, 304 and 316 are stainless and acid-resistant steel, both are sanitary stainless steel, suitable for use in coastal areas, but when the use of environmental chlorine content is relatively high, or is recommended to use the 316, because the 304 anticorrosive is mainly the form of the surface layer of chromium oxidation that is the passivation layer, when the environment of chlorine content is relatively high will corrode the chromium oxide layer, thus achieving corrosion of the substrate. High is corrosive chromium oxide layer, so as to achieve the purpose of corrosion of the substrate, but 316 stainless steel contains molybdenum, molybdenum elements added to form a special corrosion-resistant structure. 304 and 316 are sanitary stainless steel, there is no obvious difference in daily use, for example: often people ask insulation cup with 304 good or 316 good, in terms of the material of course, is 316 good, but in the use there is no obvious difference, 304 and 316 are good. There is no obvious difference in the use of 304 than 316 price is low, choose 304 can meet the demand, of course, more money or can choose 316, just in the use and will not feel the difference. Some special occasions, such as thermal expansion of strict requirements, high-temperature precision parts or to choose 316 material, after all, 316 basically does not exist thermal expansion and contraction phenomenon.

201, 304, 316 are Austenitic Stainless Steel, according to the performance of non-magnetic, some of the performance of the weak magnetic because of the smelting of the composition of segregation or improper heat treatment leads to austenite in the presence of a small amount of martensite or ferrite leads. Austenitic stainless steel corrosion resistance comes from the formation of chromium oxide protective layer on the metal surface. When the material temperature is heated to 450 degrees -900 degrees, the structure changes, will form chromium carbide along the edge of the crystal and can not form a protective layer of chromium oxide, thus reducing the corrosion resistance, which is also known as "intergranular corrosion". As a result, there are 304L and 316L, the two due to the low carbon content also reduces the intergranular corrosion. Special note is that the higher sensitivity to intergranular corrosion does not mean that non-low carbon content is more prone to corrosion, in a highly chlorinated environment, this sensitivity is also higher. Foshan Tianbiao Metal Materials Co., Ltd. specialises in providing various specifications of 201,304,316 and other materials such as pipes, plates, etc., can be whole rolls of open plate and cut to size, and accept custom-made.