What is an AL6XN pipe?
The prestigious FDA of the Food and Drug Administration of the US Government recognizes only a few alloys. AL6XN is one such super austenitic alloy with recognition by ASME BPE standards. These standards identify the many specifications in Part MM or metallic materials for these alloys. 6-moly alloy with a high molybdenum content of 6%, is best to make high strength and corrosion resistance pipes and tubes.
Al6xn Pipe dimensions, sizes and specification
What do you weld AL6XN material?
UNS N08367 welded pipe made from AL6XN material is hard to weld because it is high purity with low carbon alloy. Also, as a super-austenitic alloy with nitrogen-bearing and better performance than duplex steels, proper training is essential for proper welding for UNS N08367 pipes.
Welding AL-6XN pipe is possible using the same parameters for welding 316 steel, which includes the weld current and travel speed. But it is essential not to use filler wire but a weld insert ring for manual or orbital welding. And the insert rings should have higher molybdenum than AL-6XN alloy for compensating any dilution of alloy while cooling.
AL-6XN vs 254 SMO tube
AL-6XN and 254 SMO tubes are made from 6 moly alloys with over 6% molybdenum to have many similar properties, like resisting localized corrosion for seawater applications. Though with almost similar composition, the significant difference between the two is the high PREN of AL-6XN® alloy tubing than SMO alloy.
AL-6XN, with a high PREN of 45 than 42 SMO, makes it better for use in applications in extreme environments. A few such applications include. pharmaceutical, biotech, food, dairy, personal & home care and many others.
What is the rigid inspection process of AL-6XN tubing?
AL-6XN tubing has to undergo a rigid inspection process to fulfil the many specifications of ASME SA 249, SB 676, and ASTM A270. Such a stringent testing process makes these tubes get the recognition of the FDA or Food & Drug Regulatory a prestigious approval authority in America. Hence pipes made from these specifications are useful in the food, beverage, and pharmaceutical industries.
Inspecting pipes for high quality is a continuous process during their manufacture, from raw material to finished product. N08367 Stainless Steel Tubing undergoes many rigid inspection processes like metallurgical, NDT, destructive, hydro test, and others. A few metallurgical tests for AL-6XN high-pressure tubes include rain size, IGC or intergranular corrosion, HIC or hydrogen-induced cracking, and others.
AL-6XN vs 316L
AL-6XN and 316L are alloys of austenitic steel alloys and have many similar properties like high strength and corrosion resistance. It is because both have chromium, nickel, molybdenum and nitrogen in various percentages. But AL-6XN has a high content of all, like chromium, 20 to 22%, 316L, having 16.5 to 18.5 %.
Why is AL6XN stainless steel pipe called sanitary (hygienic) tubing?
AL-6XN stainless steel pipe is also known as AL-6XN sanitary tubing because of its many excellent properties. The chromium in the AL-6XN reacts with the steel to form chromium oxide to give outstanding corrosion resistance properties. It reduces the iron oxidation rate that corrodes sanitary pipes and tubes.
AL-6XN seamless pipe has a lifespan of over a century, which suits sanitary purposes well. And the rust-free property AL-6XN is additional property because of the high PERN of 43, which is extraordinarily suitable for sanitary usage.
