I need to spec out some high pressure ball valves for dry CO2 injection (between 1000 and 3000 psig) and was wondering about trim.
No prior experience with high pressure CO2 per se but after researching, I'm thinking electroless nickel on carbon steel for the ball and stem (since the service is relatively benign) with nylon seats but then I'm kind of stuck on the body seals. The typical Buna-N and Viton materials aren't compatible with CO2 (rapid depressurization issues) and beyond that it isn't clear from the manufacturer's literature what alternatives might be commonly available. Everyone seems to have a "proprietary" reference in their catalogues.
1. Any thoughts on seals that are commonly available and suitable for this application - dry high pressure CO2.
2. In a wet high pressure CO2 application (say Water alternating with CO2) I would switch to 316 SS for bodies and trim but would I need different elastomers ?
I guess my alternative would be to leave it open ended with a requirement that the elastomer be qualified to some acceptable test standard (NORSOK M-701, Shell, John Walker, etc.).
No prior experience with high pressure CO2 per se but after researching, I'm thinking electroless nickel on carbon steel for the ball and stem (since the service is relatively benign) with nylon seats but then I'm kind of stuck on the body seals. The typical Buna-N and Viton materials aren't compatible with CO2 (rapid depressurization issues) and beyond that it isn't clear from the manufacturer's literature what alternatives might be commonly available. Everyone seems to have a "proprietary" reference in their catalogues.
1. Any thoughts on seals that are commonly available and suitable for this application - dry high pressure CO2.
2. In a wet high pressure CO2 application (say Water alternating with CO2) I would switch to 316 SS for bodies and trim but would I need different elastomers ?
I guess my alternative would be to leave it open ended with a requirement that the elastomer be qualified to some acceptable test standard (NORSOK M-701, Shell, John Walker, etc.).