Maintenance valve used for example in tunnel boring machines, allowing for service of cylinders without shutting down the hydraulic system. Separated shut off and bleed valve guarantees safe isolation of media in accordance with DIN EN 982 with locking device for up to 3 padlocks and integrated on/off label.

1. Normal operating position
   In this position the main valve is open and the bleed valve is   closed.
2. Main close position
   First step in locking out the hydraulic supply to the machine is to  close the main valve.
3. Bleed position

Second step is to bleed the hydraulic consumer through the bleed val- ve. Through the cam plate design the bleed valve can only be operated if the main valve is closed. The possibility to lock the valve position  with up to three padlocks ensures a safe maintenance service for the workers.