The backstop designs are externally mounted, self-contained on a shaft extension with a torque arm. (The original design was flange mounted onto the high speed shaft of the gear drive.) The external versions are available for both high speed (the RDBK-E, lift-off design) and low speed rotating shafts (the RDBR-E roller ramp design).
The torque capacity is up to 350,000Nm, although this will be extended up to 700,000Nm, says the company. Special solutions are available for where a higher torque capacity is required.
