Standard & Non-Standard Shaft Key Sizes

When preparing to install sheaves or sprockets using either TaperLock or QD bushings, it is helpful to know what key sizes will be needed so key stock material can be obtained in advance.  While this information can be found in various industry publications, it is not often presented in a direct and concise form.  The following table includes standard rectangular shaft key sizes for shaft diameters ranging from 5/16" to 9":

 Standard rectangular key stock is readily available from most Gates Industrial Distributors.

As bushing bores approach the maximum recommended diameters, keyway depths are reduced in order to extend maximum bores as much as possible.  Reduced keyway depths then require special non-standard shallow shaft keys.  Because these special shaft keys are not readily available, the appropriate size is included with each bushing.  The special non-standard shaft keys required for TaperLock bushings are included in the following table:

This table includes the specific bushing size that each bore range and non-standard shaft key correspond to for handy reference.

The non-standard shallow shaft key sizes used for QD bushings are not all the same as for TaperLock bushings and bore ranges differ, so the following table includes special non-standard shaft keys required for QD bushings:

This table also includes the specific bushing size that each bore range and non-standard shaft key correspond to for handy reference.

A valuable part of every installation job is obtaining all needed components and then confirming that those received are correct.  These tables will enable installers to quickly confirm shaft key sizes needed for both TaperLock and QD bushings over a broad range of bores.
Feel free to contact us at ptpasupport@gates.com or 303-744-5800 if you have any questions.