316L Stainless Steel Pipe VS 1.4404 SS Pipe
316L stainless steel tube has good corrosion resistance and mechanical processing properties, it is not only widely used in the chemical industry, also have a wide range of applications for other industries. 316L stainless steel is one of the typical representatives of austenitic stainless steel, and is also the most widely used material, especially in the European Union, the United States and some other developed countries.
So what is the difference between 316L and 1.4404, are they equivalent grade? Because we often have customers who need 1.4404 stainless steel pipe and fittings, we are unable to provide 1.4404 in practice and can only replace it with the ASME grade. So let’s take a sample of stainless steel pipe today and analyse whether they are interchangeable.
Why We Have This Question
Because we have a lot of customers in projects where they need EN/DIN standards. And EN standards are not common grades in the Chinese domestic market. When customers need small quantities, we usually request them to check if we can use equivalent ASME grade to replace EN grade, because ASTM is more readily available. So this brings us to the question, we will do a brief analysis today from their chemical composition and mechanical properties.
Most of 316L available is usually produced to the American Standard in China. For cost reasons, steel mills generally lean the Ni content of their products as far down as possible. The American standard stipulates that the Ni content of 316L is 10-14%, while the European standard stipulates that the Ni content of 316L is 10-13%. Due to the high price of nickel and the need for steel mills to reduce costs, the actual Ni content we detect is usually between 10.01 and 10.5, and rarely higher than 10.5.
316L VS 1.4404
Please see Table below, TP316L composition from ASTM A312, and 1.4404 from EN 10216-5 standard, they are the common standard for stainless steel pipes in the US and EU respectively. By comparison, we found that 1.4404 has a clear N content requirement and a minimum Cr content requirement of 16.5. The other values listed here are maximum requirements, so we think the other elements are the same. If TP316L is used instead of 1.4404, then it is important to consider whether the Cr content meets the minimum requirement of 16.5. If the Cr content is between 16.0 and 16.5, it would be a question we need to consider whether this is acceptable to the customer.
As we can see from the table below, the requirements for 1.4404 stainless steel tubes are higher, but the difference is not significant. According to our practical experience, ASTM A312 TP316L is able to meet the requirements.
From the above comparison, we think that TP316L is an alternative to 1.4404 if the customer has no special requirements. So if you need stainless steel pipe and fittings in 1.4404, please consider to allow us using 316L to instead of it if the quantity is not considerable.