Filler for 316 to LCS
Posted: Mon Oct 30, 2017 11:05 pm
I'm preparing to work up a PQR for joining 316L to LCS pipe. Investigating the filler choice I find that 309 is not suitable because 316L needs moly in the filler to maintain parent alloy. 309 has no moly. I looked at 312, surely it has moly, nope. Super missileweld, nope. Stumped, can't find a suitable filler. Anybody know of one?
Got to thinking of consequences of using 309 anyway. The main difference between 304L and 316L (and 309) is the moly, 304L and 309 has none. Carbon, chrome and nickel content are similar so if 309 is used to join 316L to LCS the result would be reduction in moly in the local parent fusion zone making it more like 304L. If I don't need the extra corrosion resistance that 316L provides over 304L (which I don't), strength should be maintained and 309 should be OK to use.
Can't find anything in Australian Standards specific and don't have access to AWS, ASME or EN.
Anyone find any flaws in this logic or got anything to add?
Reason for using 316L. Coupon will be 2" sched 160, available in 316L but haven't found any in 304L yet.
Got to thinking of consequences of using 309 anyway. The main difference between 304L and 316L (and 309) is the moly, 304L and 309 has none. Carbon, chrome and nickel content are similar so if 309 is used to join 316L to LCS the result would be reduction in moly in the local parent fusion zone making it more like 304L. If I don't need the extra corrosion resistance that 316L provides over 304L (which I don't), strength should be maintained and 309 should be OK to use.
Can't find anything in Australian Standards specific and don't have access to AWS, ASME or EN.
Anyone find any flaws in this logic or got anything to add?
Reason for using 316L. Coupon will be 2" sched 160, available in 316L but haven't found any in 304L yet.