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What is the classification of stainless steel pipe?

301– Good ductility for molding products. It can also be quickly hardened by machining. Good weldability. Wear resistance and fatigue strength are better than 304 stainless steel.
302– The corrosion resistance is the same as 304, and the strength is better due to the relatively high carbon content.
303– Make it easier to cut than 304 by adding small amounts of sulfur and phosphorus.
304– that’s 18/8 stainless steel. GB brand number is 0Cr18Ni9. 309- Has better temperature resistance than 304.
316– After 304, the second most widely used steel, mainly used in the food industry, pharmaceutical industry and surgical equipment, the addition of molybdenum to make it a special corrosion resistant structure. It is also used as “Marine steel” because of its better chloride resistance than 304 stainless steel tubes. SS316 is commonly used in nuclear fuel recovery units. Grade 18/10 stainless steel tubes usually also meet this application grade.
Model 321- Similar to 304 except that the addition of titanium reduces the risk of weld corrosion.

Series 400 – Ferrite and Martensitic stainless steels.

408- Good heat resistance, weak corrosion resistance, 11% Cr, 8% Ni.

409- Cheapest model (Anglo-American), usually used as a car exhaust pipe, is a ferritic stainless steel (chromium steel).

410- Martensite (high strength chromium steel), good wear resistance, poor corrosion resistance.

416- The addition of sulfur improves the processing properties of the material.

420-” tool-Grade “Martensitic steel, similar to brincott high chromium steel, the earliest stainless steel. It is also used in surgical knives and can be made very shiny.

430-Ferrite stainless steel, for decorative purposes, e. g., for automotive accessories. Good molding, but poor temperature resistance and corrosion resistance.

440-High strength cutting tool steel, slightly higher carbon content, after appropriate heat treatment can obtain higher yield strength, hardness up to 58HRC, belongs to the hardest stainless steel. The most common example is the razor blade. There are three commonly used models :440A, 440B, 440C, and 440F(easy to process).

Series 500 – Heat resistant chromium alloy steels.

Series 600 – Martensite precipitation hardened stainless steel tubes.


Post time: Jul-11-2022