1. Classification of stainless steel pipe
Steel pipe is divided into ordinary carbon steel pipe, high quality carbon structure steel pipe, alloy structure pipe, alloy steel pipe, bearing steel pipe, stainless steel pipe, bimetal composite pipe and so on. As one of the commonly used steel pipe, stainless steel pipe are of many kinds and widely used.
Stainless steel tubes can be divided into Cr system (400 series), CR-Ni system (300 series), CR-Mn-Ni (200 series) and precipitate hardening system (600 series).
301----- Good ductility, used for molding products. They can also be hardened rapidly by machining.
302----- corrosion resistance is the same as 304, because the carbon content is relatively higher and the strength is better.
303----- by adding a small amount of sulfur, phosphorus to make it easier to cut than 304.
304----- is 18/8 stainless steel. GB 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 gives it a special corrosion resistance structure. Because of its better chloride corrosion resistance than 304 stainless steel pipe, it is also used as "Marine steel". SS316 is usually used in nuclear fuel recovery units. Grade 18/10 stainless steel pipe is also normally qualified for this application grade.
408 -- Good heat resistance, weak corrosion resistance, 11% Cr, 8% Ni.
409 -- The cheapest model (Anglo-American), usually used as an automobile exhaust pipe, of 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 - "cutting tool grade" martensitic steel, similar to Brinell high chromium steel, the earliest stainless steel. Also used in surgical knives, can do very bright.
430 -- ferritic stainless steel for decorative purposes, e.g. car ornaments. Good molding, but poor temperature resistance and corrosion resistance.
440 -- High strength cutting steel, slightly higher carbon content, after proper heat treatment can obtain high yield strength, hardness can reach 58HRC, is one of the hardest stainless steel. The most common example of this application is the "razor blade". There are three commonly used models: 440A, 440B, 440C, and 440F (easy to process).
600 series- Martensite precipitation hardened stainless steel tubes.
2. Stainless steel application requirements
The main use of stainless steel is the exhaust system, accounting for the total amount of automobile stainless steel 1/2 above, 80% for ferritic stainless steel. The exhaust gas produced by the automobile engine flows out of the muffler through the exhaust inlet pipe, front pipe, hose, converter, center pipe and finally. Exhaust system commonly used steel 409L, 436L and so on. Automobile mufflers mainly use stainless steel welded pipes. It is estimated that the stainless steel pipe used by the car accounts for about 1.5% of the whole downstream of the stainless steel pipe consumption, and the use of stainless steel seamless pipe and welded pipe ratio of about 2:1.
The demand for stainless steel pipe is great, the industry mainly uses stainless steel seamless pipe, specifications include: 304, 321, 316, 316L, 347, 317L, etc., the outer diameter in ￠18-￠610, the wall thickness in 6mm-50mm or so (generally choose specifications in φ159mm above the medium and low pressure pipeline), the specific application field is: Furnace tube, material conveying tube, heat exchanger tube, etc.
3. What is the difference between stainless steel pipe and carbon steel pipe
Carbon steel pipe can also be called carbon steel tube, such as the common Q195, Q235. Carbon steel can also be called magnet alloy steel, in addition to carbon, iron, and no other metal elements. And stainless steel is chromium nickel steel. In addition to carbon and iron, there are chromium, nickel, copper and other metal elements. In the steel pipe containing more than 12.5% chromium will form a protective film on the surface of the steel pipe (passivation film), so as to achieve the effect of corrosion resistance. So the main difference between the two is corrosion resistance, carbon steel pipe is easy to rust, and stainless steel pipe is corrosion resistant steel.
4. China Stainless Steel Pipe Manufacturers
HDT Tubing Co.,Ltd (https://www.hdtsteel.com) is a large Chinese manufacturer of stainless steel pipe. We have advanced production equipment, strong technical strength and perfect after-sales service. The steel products we produce are of high quality and comply with international standards. The company has sufficient inventory and provides 24-hour online service. Customized purchases are welcome.
Our stainless steel pipes have been sold to many overseas countries and received good comments from customers. Welcome to order again!