When welding stainless used in food service, you then need to re-passivate all the joints. Can be a bit of a pain for long pipelines. You'll often see acrylic

When welding stainless used in food service, you then need to re-passivate all the joints. Can be a bit of a pain for long pipelines. You'll often see acrylic piping used in food plants partially for this reason (another reason is that it's easy to see any blockages or growths etc through the pipe walls).