Your pipeline can be protected even without power supply


With the Fahlke MHAZ® your pipeline can be protected against overpressure, underpressure or line breaks even without power supply.

How does the system work

Pressure is built up in the pressure accumulator with the Fahlke hand pump. Herewith, you can automatically move your valve, for example, up to three times and monitor the line with an integrated pressure pilot and, as needed, automatically move to the failsafe position. Thus, a power supply on site is not necessary.


Alternatively, the Fahlke MHAZ®-SR can be used, which moves your valve by spring force in the failsafe position you predefined.


Furthermore, solenoid valves for automation and remote control of your valve can be integrated in the control. Manual operation on site is also possible.


The system is built in the tried and tested Fahlke modular technology (MCE) and is thus leak-proof and provides a maximum of compactness, user friendliness and operability. With the individually combinable hydraulic Fahlke MHAZ control units nothing stands in the way of the perfect safety device.


You have a choice among numerous components, which can be integrated such as solenoid valves, pressure limit valves, line break detection systems for all standard or control processes of your valves or for high and low pressure protection; differential pressure controls can also be integrated.

Technical data

  • Double-acting (failsafe close / failsafe open / fail in position)
  • Spring force return (SR)
  • Actuation via integrated hand pump
  • Control cabinet of mat. 1.4301
  • Pressure reserve accumulator for up to 3 actuator strokes
  • Pressure monitoring with system pressure gauge
  • Control voltage: 24V DC / 110V DC / 220V DC // 230V AC, 13W (optional)
  • Signalling of the end positions: Open / closed / current position (4-20 mA) (optional)
  • Actuator/gear protection class: IP68
  • Temperature range: -60°C to +70°C
  • Safety systems: Spring-return, hydraulic pressure accumulator, hand pump


  • Functions: Emergency Shut Down (ESD)
  • Pressure monitoring (high pilot and/or low pilot)
  • Line break detection system (LBC, pneumatic)
  • Control on a separate stand
  • Galvanic separation from the cathode-protected pipeline
  • Isolating spark gap