Standard
Traction Coefficient Measurement
2013-02-12
WIP
ARP6243
Aviation oils provide thin lubricating films between highly stressed bearing, gear and other lubricated contacts. The stresses and shear rates cause rapid rheological changes in the oil which affect the traction (friction) between the surfaces. Thin film dynamic forces are associated with the molecular structure of the oil provided by the oil supplier. Traction force divided by the normal load (i.e. traction coefficient) can be viewed as a fundamental property of aviation oil. Its value is a function of stress, temperature and shear rate. Appropriate measurements are made under dynamic conditions to characterize aviation oil products for engineering design purposes and service performance prediction.