The Vickers Model MHT50 vane motor with 38 in3/rev maximum displacement was chosen for an example. This motor is rated for a maximum pressure of 4000 psi. Maximum continuous speed at 3000 psi is 200 rpm and maximum speed at 2000 psi is 350 rpm. Efficiencies were calculated for an input flow of 35 GPM.
Volumetric efficiency declined linearly as pressure increased from 1000 to 3000 psi (Fig. 5.9). Torque efficiency increased as pressure increased from 1000 to 2000 psi and remained approximately constant at higher pressures. The decrease in volumetric efficiency was offset by the increase in torque efficiency in the 1000โ2000 psi range, and overall efficiency decrease was moderated. Overall efficiency declined from 85.4 to 81.2% as pressure increased from 2000 to 3000 psi.
