Keyed shafts rotate inside axial bearings to transmit power. Keys are fit into keyways to fix wheel hubs, gears, sprockets, and other accessories to keyed shafts.
Power transmission often requires rotating shafts with sprockets, brakes, pulleys, gears, wheels, and many other types of devices attached in unique configurations.
A round steel shaft with a keyway allows for similarly keyed interchangeable components to be positioned securely along it's entire length. Such a shaft can be manfactured from round stock with as little as a broach and a hammer.
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ISO 500-3 for PTO splines<br> ISO 5673-1 is a good start for other splines.<br> ANSI B92.1<br> DIN 5480 & ISO 4156<br> JIS B1603<br>
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