The direction of flow of the compressed air is determined by means of a check valve. While the compressed air can flow freely in a given direction, the backflow in the opposite direction can be blocked.
Controlled check valve
A controlled check valve has the advantage over mechanical non-return valves that the blockage can be released and also reactivated by means of a pneumatic signal (control air connection).
Stop valve
With a stop valve, the compressed air can flow in both directions. The valve is closed or opened by a control signal. Stop valves are often used on pneumatic cylinders, so that the cylinder piston can be stopped quickly and accurately for positioning tasks or in emergency switching.
Throttle check valve
The throttle check valve is a special type of check valve. This valve shape can be found in the product area flow control valves.
Connection sizes
| Valve type | Connection sizes |
| Check valve, mechanical | Plug connection 4 to 12 mm, G 1/8 to G 2 |
| Check valve, controlled | G 1/8, G 1/4 |
| Stop valve | G 1/8, G 1/4 |
