13 Mechanical Power Transmission Systems

The purpose of this section is to describe world standards for the most commonly used power source in industry — the electric motor — and some of the important power transmission components, such as transmission chains and sprockets, endless belt drives, metric module gearing, splines and serrations, and keys and keyways. Some standards for these items have been based on the metric measuring system, and the others on the customary inch system. The main differences will be pointed out in this chapter to facilitate worldwide interchangeability of parts. A number of ISO and IEC standards have been issued on the subject, and some of the most important standards, as well as the ISO technical committee organizing the technical work behind each standard, are listed at the end of the chapter. Note that the technical committees are designated by the letters TC, followed by the appropriate committee number.

Information presented in ISO and IEC standards and draft proposals have been included, but since they are subject to change, care should be exercised with some of the material presented.