Page 255 - Subyek Teknik Mesin - Forsthoffers Best Practice Handbook for Rotating Machinery by William E Forsthoffer

4

Gear and Coupling Best Practices

Gears pitch line velocity and the number of teeth per inch
of pitch diameter.
Gears have a greater potential for low reliability
than other types of rotating equipment, because Couplings
they use gear meshes, and a minimum of four
bearings to transmit torque and change the speed of Couplings in current use are normally dry, non-lu-
the driven equipment. Gears typically have thou- bricated types that use discs or diaphragms to
sands of gear teeth meshing per second, and require transmit torque and allow misalignment and axial
proper alignment and lubrication to achieve opti- movement.
mum reliability. Figure 4.1 below is a plot of the This chapter will present gear and coupling best
number of gear meshes per second as a function of practices used since the 1970s.

Fig 4.1 Tooth engagement frequency

Copyright Ó 2011, W E Forsthoffer. Published by Elsevier Ltd. All rights reserved