The B6R series is not a standard back pressure regulator being pressed into service for supercritical back pressure let down in a supercritical extraction system. The B6R (patent pending) is designed from a clean sheet to specifically address the demands encountered when rapid cooling occurs as a supercritical gas expands during decompression. The body is CNC machined from premium stainless steel 316/316L dual cert alloy bar stock. The diaphragm material choices include polyimide, PTFE, and PEEK depending on the co-solvents used and the maximum temperatures. O-ring cavities are designed to limit the explosive decompression that occurs when the SCO2 permeates the o-ring material. O-ring choices include Buna-N, Viton, PTFE, and DuPont Kalrez as determined by your application. The flexible diaphragm membrane is the only moving part. This membrane directly seals against field of multiple parallel orifices. The shape of the internal passages prevents the accumulation of ice or viscous oils so that the B6R remains free to keep the pressure regulated at your target set point.