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HYGUARD® –hydraulic safety coupling

HYGUARD® –hydraulic safety coupling

The primary task of overload protection devices in the drivetrain of machine systems is to protect valuable capital goods against damage due to the occurrence of unexpected and excessive strains.

Nonetheless, it is impossible to completely exclude machine breakdowns caused by sudden overloads that cannot be predicted. However, a single incident of damage can be far more costly than an effective overload protection device. Appropriate safety equipment is therefore still necessary to protect such systems. In the area of the drive train, these primarily include safety couplings, which are available in a wide range of designs today. With the HYGUARD® hydraulic safety coupling, the torque is transmitted exclusively via friction between the hydrostatically loaded surfaces of the shaft and hub. It functions without slippage as long as the preset torque is not exceeded.

If the torque exceeds this value, the hydrostatic pressure is swiftly released, shutting down the drive train immediately. Recommissioning requires little time. The system simply needs to be placed under pressure once more.


  1. Transmission of high torques in a small space
  2. Torsionally rigid / articulated shaft connections in conjunction with curved-tooth couplings®
  3. Overload protection with adjustable torque limitation
  4. Release accuracy of +/- 7–10%
  5. Constant release torque throughout the entire period of operation
  6. No disruption of operation due to material fatigue; low costs due to downtime
  7. Extremely rapid recommissioning
  8. No cost-intensive stocking of spare parts

Relevant products

Torsional flexible coupling | ELCO

Basic series

Gear joint couplings

Gear spindle couplings

High-speed series

Shifting gear coupling

Couplings Solutions Team

Get in touch with our experts in case of any questions:

Couplings Solutions Team
Phone number
+49 821 5700 0
[email protected]

Couplings Solutions Team

Phone number
+49 821 5700 0