Working through a batch of parts where the drawing says 316L and I’m not convinced the material call is doing any real work there, so I’m curious how other shops decide.
Both grades come through the shop regularly. The way I’ve been looking at it:
- 304 is fine for most general hardware. Decent corrosion resistance, machines predictably, easy to get.
- 316L earns its cost when the environment gets hostile: repeated washdown, standing moisture, chemical contact, or anything with chlorides in it.
What muddies it for me is food and packaging work. The material call tends to get tangled up with surface finish, how the thing gets cleaned, and whether the part geometry holds a puddle or drains. Specifying 316L on a part with a rough finish and a crevice in it doesn’t really buy you the corrosion resistance you thought you were paying for.
So where’s your line? Cases where 316L is genuinely required, and cases where you’d push back and run 304 instead?