The external gear pump generally speaking is simple in const

The external gear pump, generally speaking, is simple in construction and low in cost, but its volumetric efficiency is not so high as that of the piston pump. In design of a gear pump, a variety of measures can be taken to reduce the leakage. Give at least 3 ways to improve volumetric efficiency.

Solution

Gear pump volumetric efficiency can be enhanced by increasing the oil viscosity,due to increasing the oil viscosity the volumetric efficiency can be improved.

The volumetric efficiency has to be improved by minimizing the mechanical tolerances of manufacturing .

Gear pumps can produce a high frequency pressure pulsation and thus increase of fluctuations of delivery flow ‘flow rate ripples’ in suction and impulsion chambers, which tends to damage pressure gauges. To reduce the ripples, tooth profile, gear shape and pump body plates are needed to be improved. Investigations show that it is not possible to get external gear pumps with no delivery fluctuation . The efficiency of the pump is directly related with the relationship between the moving parts and clearances factors. In addition, the viscosity of the flow will effect for a thin fluid (such as water) or a moderately viscous fluid (such as particular oil). Increasing the performance of an external gear pump can be achieved by reducing the size of the pump, increasing the pressure as well as the rotational velocity.