Working on biogas compressor units where they have 350Bar very natural gas vibrating at 100+ mm/s and the pipe couplings leak and at one plant piping broke so it´s suddenly full gas. So on the coolers they swapped from stainless to copper tubing for the water when rerunning the piping, still at 100mm/s at normal operation, my issue was on how much better the copper piping is compared to stainless regarding fatigue? Or am I wrong and it will fail quicker? I am suggesting some support so we hopefully never will know from this case but I was wondering. Olov

There's an issue of alloy and piping configuration and a photo would help. Were there pigtails and loops to remove hammer and control expansion? What type of couplers or joints?

First thought would be: SS is better.