In this category we gathered sophisticated valves, performing very specific functions, and which are usually installed directly after air preparation unit.
One of those valves is so called soft start valve, which is used to avoid equipment damage or injuries caused by rapid hit of pressure into pneumatic system. The valve elements allow for the smooth pressure build-up to the 50% set value, further increase occurs instantly.
Closing valve serves for somewhat similar purpose, but in this case it protects sensitive equipment from damages caused by power (electricity) failure. In situation of power outage valve will close and cut off pressure from the system.