The data in this catalog is given at its worst condition. Moment of inertia was calculated for each of the customer’s largest B1 bore combined with the smallest B2 bore shown for each size coupling. Torque and torsional stiffness tests were performed at the maximum misalignment ratings, not in a straight line.

The torque rating is the buckling point of the beams, not the breaking point. If the buckling point is exceeded, the beams have gone beyond the elastic limits and will fail.

These ratings have no safety factor. We want you, the customer, to know what the worst conditions are that can be expected. You decide what safety factor is needed for your application.   

    
Torsional Deflection, Torsional Stiffness, Torsional Rigidity and Wind-Up are all synonymous. Windup occurs when torque is applied and the rotation of one end of a shaft is greater than the other end. The ratings in this catalog are shown in arc minutes per newton meters and per pound inch at their maximum misalignment rating NOT WHEN THE SHAFTS ARE IN PERFECT ALIGNMENT.

Hysterisis or Lost Motion
This occurs when the driven shaft side of the coupling winds up after the drive shaft side has decelerated to zero RPM. When the direction of rotation is reversed it unwinds and rewinds before driving the driven shaft.

Backlash
The motion between two or more parts of one component or two components connecting two shafts such as two gears, some belts and pulleys, and some take apart flexible couplings.

Static Torque
Torque applied while in a non-rotating condition. Rocom static torque ratings are below the buckling point of the flexible beams. If the beams are run in a buckled condition or have exceeded the torque rating, the coupling will fail.

Please note: The correct dynamic safety factor should be determined by the customer in accordance with the system's requirements.

Click here for Flexible Couplings Installation