Experimental tests of pressure pulsation of gear pumps

The paper presents results of experimental tests regarding pressure pulsation of the gear pump with external gear design. A cycle of measurements was carried out in relation to the selected parameters of system’s operation such as temperature of hydraulic fluid (viscosity) and pressure of the pressure line. The obtained results of pulsation measurements were analyzed in terms of time and frequency. The time analysis was carried out in order to determine the peak-to-peak value of pumping pressure that is responsible for generating increased levels of vibration and noise, as well as influences fatigue wear of the hydraulic system elements. The frequency analysis was carried out in order to identify the pressure values not related to periodical changes in pump capacity, which may be used to diagnose the operation condition of the pump. Research has shown that increase of pumping pressure and temperature of the oil causes significant increase of the pressure pulsation amplitude resulting from the eccentricity of gearwheels.