Stainless Steel 316 Pipe and Stainless Steel 316L Pipe are two of the most popular austenitic stainless steel piping materials that are remarkably resistant to corrosion and have high durability. Both grades comprise chromium, nickel, and molybdenum, while the addition of molybdenum facilitates the resistance to pitting and crevice corrosion caused by chlorides in the environment, especially seawater or chemical processing plants.

The main distinction between the two is carbon content. Stainless Steel 316L Pipe has a lower carbon content (generally a maximum of 0.03%) than Stainless Steel 316 Pipe (up to 0.08%). The lower carbon content in stainless steel 316L helps to prevent carbide precipitation during welding, which in turn reduces the risk of intergranular corrosion of welded structures. Therefore, 316L is generally the first choice in fabrication works which involve a lot of welding.

They are normally produced in accordance with ASTM A312 and ASME SA312 standards, which specify the requirements for seamless and welded austenitic stainless steel pipes. Dimensional standards might also be compliant with ANSI or ASME B36.19 specifications. In real-life scenarios, Stainless Steel 316 and 316L pipes find application in the processing of oil and gas, petrochemical plants, marine systems, power generation, and construction industries. Their selection is based on their high strength at elevated temperatures, superior resistance to corrosion, and good formability.

In summary, both grades are capable of performing well in highly demanding industrial environments. The decision whether to use 316 or 316L is mostly influenced by the welding requirements and the conditions of service.