Check valves that trigger at a certain pressure?

[Al Skierkiewicz]

There is actually a check valve in the output of many of the legal compressors. It is required for operation. However, in all cases, COTS pneumatic parts must allow all stored pressure to be released when the Pressure Vent Plug Valve is operated.

[FrankJ]

What you are looking for is called a back pressure valve. The simpler ones are essentially a check valve with either an adjustable spring tension or preset to open at the desired pressure. "back pressure valves" were not a listed legal component under 2016 rules. "Check valves" were listed components and legal under 2016 rules. A definition thing. In any case it would have to be plumbed to meet the other rules, as Al said. The relief valve required on the robot is actually a check valve with adjustable opening pressure.