General Purpose vs. Special Purpose Couplings.
Flexible couplings are a vital part of a power transmission system. What type is selected, how much the coupling costs, and how much effort one spends on selecting a coupling and determining how it interacts with a system should be a function of the cost of the equipment and how critical it is to the plant. In some cases, the coupling used will be a general purpose coupling and the selection process will take little time. However, for more critical equipment, the coupling used maybe a special purpose coupling and the selection process may take a great deal of time. When selecting couplings, one must also consider the application and past experience. One must evaluate the coupling's initial cost and also the ease of maintenance and replacement of the flexible elements, along with the lubrication schedule or lack of it. Then one must trade off features and characteristics of available couplings and pick the best one suited for the application.
Mancuso, Jon (1994). General Purpose vs. Special Purpose Couplings.. Texas A&M University. Turbomachinery Laboratories. Available electronically from