Dynamic test benches for gear units

Helicopter manufacturers around the world rely on VISCOTHERM technology to test the stringent requirements related to quality, reproducibility and the safety of mechanical drive systems. As the heart of dynamic test benches, the ROTODIFF solution from Viscotherm AG guarantees that these test benches can be operated with a fraction of the turbine power. In addition, this method allows gear units to be tested at various gear ratios under the stipulated operating conditions. In addition, dynamic test benches with the ROTODIFF can be operated in a mechanically closed loop, which substantially reduces energy consumption. 

Drive system for helicopter test benches

VISCOTHERM ROTODIFF units are used in test benches for helicopter gearboxes. The double transfer seal motors specially developed by Viscotherm AG meet all the requirements for use in complex closed-loop test benches of this kind. The energy consumption is significantly reduced by using ROTODIFF technology in the closed-loop set-up. Modern multipurpose test benches also make it possible to test gearboxes from different helicopter models on the same test bench. 

Test criteria

Manufacturers of helicopters use test rigs for new production and for maintenance and reconditioning purposes to test the helicopter gears on both the main and the rear drives. In addition to the main motor gear (MGB), the intermediate gear (IGB) and rear gear (TGB) are also tested.

The test criteria also include, in addition to the revolutions of the rotor and the torque, the oil pressure of the gearbox, the temperature of the lubricant and the oil temperature. These measurements are carried out with the gear box placed under load and are tested to ensure that threshold values are maintained.