Highly durable: Page 3

In order to achieve reproducible trial results, it is necessary to subject the test gearbox only to the known, specified load and speed levels. The test gearbox is therefore decoupled from the reverse transfer gearbox and from the star gear using the ROBA-DS shaft couplings. Due to alignment deviations during installation and load displacement in operation, 0.2 to 0.8 mm axis displacement and minor angle misalignments may occur. These axis and angle misalignments must be compensated for by the shaft couplings. A ROBA-DS disk pack coupling Size 2200 in double-jointed design is installed between the test and the reverse transfer gearbox.At 24,000 Nm, the nominal torque lies slightly over the maximum test torque. Other ROBA-DS disk pack couplings are used in the test stand bracing cycle.

Test stand coupling requirements are subject to highly diverse requirements. In flywheel mass test stands, large flywheels are accelerated with high mass moments of inertia to high speeds. Shaft couplings which transfer the stored kinetic energy onto the test item have to be extremely robust, reliable and dimensioned for high test stand speeds. Should shafts be connected over longer distances in high-speed test stands, it is often necessary to position a length-adaptable sleeve between the two coupling hubs. The bend-critical speed for the sleeve must not lie within the operating speed range. Intermediate sleeves made of carbon fibre-reinforced plastics (CRP) allow high speeds even for long couplings. In comparison to steel sleeves, these CRP variants have a far higher bend-critical speed. Apart from that, the CRPsleeves weigh up to 80% less. This characteristic is particularly valued for large construction sizes and long sleeves. A further advantage of this plastic material is its high corrosion resistance. If leakage current resistance, meaning electrical insulation, is also required, glass fibre-reinforced plastic (GRP) is used instead of carbon fibrereinforced plastic. The other characteristics of this material are approximately identical with carbon fibre-reinforced plastic.