Compressed Air Grooved Piping

[goldnwhite]

I have a project for compressed air piping (50 psig sterile air used in our process) and in the specifications to contractors I asked for 304 SS, Schedule 10 with Victaulic fittings. It came to my attention that one of the contractors actually may have bid Gruv-lok (calling it "combination grooved fitting and butt welding methods" in the quote). I understand there's a difference due to extra welds on the Gruv-lok and, more importantly from a fair bidding standpoint, there is a price difference. Gruv-lok was almost used in the past here, but got nixed for hot water piping due to corrosion concerns at the welds. This judgement was probably not based on any engineering standards. A lot of knowledge around here comes from what I like to call "tribal knowledge" and isn't really based on engineering so I'd like to know if Gruv-lok got a bad rap from this previous project or is there an industry standard. Also, is there any rationale behind specifying one or the other for the air piping in this project?

Thanks for any clarification.

 

[TBP]

Gruvlok is the Grinnell (now Anvil?) equivalent of Victaulic. No welding involved. Any place I've seen with problems with grooved piping in general has normally:

a/ used the wrong gaskets for the service or

b/ failed to make proper expanion allowances for systems that heat up.