COUPLING SLEEVE

The curved OGEE* lines printed on the outer surface of the coupling sleeve are intended to be used as a simple torque indicator. The curves have been designed to become straight lines under given torque conditions. Hence, by viewing the coupling whilst running, with the aid of a stroboscope, a load estimate can be made. The lines have been nominally set at zero (C), nominal (B) and overload torque (A) for both directions of twist:

OGEE* lines at overload torque

As the sleeve nears the end of its design life, under normal ambient conditions, the torsional characteristics will change and you will see line straightening at lower torque values than those previously observed. This change can be used as an indication that the sleeve should be replaced. 

Note: When viewing the coupling, normal safety procedures must be followed and the use of a transparent guard is recommended.

* Patent applied for.