ELIN Motoren and Voith launch electric motors with integrated safety coupling for the reliable and maintenance-free operation of tunnel boring machines

Depending on size and geology, the cutting head of a TBM is powered by between four and 24 drive units. These drive trains consist of a pinion, planetary gear unit, torsion shaft, safety coupling, and electric motor and represent the heart of a TBM that should be protected. Clogging in the cutting head causes a sudden torque much higher than the maximum permissible torque with which the drive train is rated. As it is activated at a predefined torque, the integrated safety coupling in the new MKH-SafeSet and MKH-SmartSet electric motors from ELIN Motoren accurately and reliably protects all the drive train components of tunnel boring machines. A triggered coupling can be re-activated within just a few minutes. If only a few couplings are released, the TBM can continue to tunnel until the next maintenance shift.

The weight of the new Voith SafeSet has been reduced by more than 80% and is only around 15% of that of conventional safety couplings. A lower mass minimizes rotor inertia and the bearing loads of the drive train, whichimproves efficiency and achieves lower temperatures, thus extending the service life of the drive train.

The MKH-SmartSet is an optional add-on to the MKH-SafeSet and allows continuous tunneling despite any torque peaks that are non-critical for the drive train. Adding a SmartSet results in an automatic reset if the TBM slows down or comes to a stop which allows continuous operation, even if the frequency of high torque load peaks increases, which positively affects the productivity of the TBM.