Carbon steel seamless pipe is often referred to as carbon structural steel. It is iron, carbon and manganese as the main elements except C. It is not divided into other alloying elements. It is mainly divided into 10# seamless steel pipe, 20 # seamless steel pipe, 45# seamless steel pipe, of course, C is also controlled to a certain extent, and the hardness is larger than pure iron. Carbon steel has low cost, is prone to rust, and has a short use time, and is used in various structures and pipes that do not have any corrosion resistance.
Stainless steel pipe refers to alloy steel containing less than or equal to 13% Cr and not in the atmosphere. There are many types of stainless steel, such as ferritic stainless steel, austenitic stainless steel, and martensitic stainless steel. Different stainless steels have different resistance to corrosion and different corrosion resistance to different media. It is also different in terms of magnetism. Carbon steel is magnetic, and stainless steel generally does not have magnetic or magnetic properties.
The stainless steel tube contains a large amount of chromium, and some contain a large amount of nickel and a certain amount of titanium. The role of chromium is to make steel corrosion-resistant. Nickel is the main alloying element for the formation of austenitic stainless steel, but the role of nickel can only be fully demonstrated when it is combined with chromium. If pure nickel is used, a pure austenite single-phase structure is required in low-carbon nickel steel, and the nickel content needs to be more than 24%. In fact, when the nickel content needs to reach 27%, the corrosion resistance of the stainless steel pipe can be remarkably improved. , so there is no nickel as an alloying element in the stainless steel tube.
Common stainless steels are mostly austenitic stainless steels, such as 304, 316L, 321 and so on. The carbon content is lower, but the alloying element content is above 20%, of which the chromium is 18-20%, the Ni content is 8-10%, and there are elements such as vanadium, molybdenum and titanium. The stainless steel is used for corrosiveness. In the medium, especially in foods with high requirements for ring conditions, pharmaceuticals, daily chemical cosmetics and other industries, most of them are used. Of course, the chemical industry is also widely used. However, austenitic stainless steel is afraid of chloride ions and is very strict in controlling the chloride ions of water in the environment.