The speed of the pump is limited by the actual operating conditions. If the viscosity of the fluid being metered is high, after the pump speed exceeds a certain point, the fluid cannot enter the interdental space and the pump cannot obtain enough fluid to maintain normal volumetric efficiency. Lack of sufficient feed is known as underfeed or cavitation. It can be solved by increasing the inlet pressure of the pump or reducing the speed of the pump.
The metering of low viscosity fluids requires a different approach. Since the lubrication of the bearing surfaces within the pump is dependent on the fluid being metered, the speed is limited. High speeds can cause increased wear and even seizure, which is more likely to occur if the fluid has poor lubricity or contains abrasive particles. Therefore, in some applications, it is recommended to use a large displacement pump for low speed operation.
For the specific situation of the pump speed, please contact our engineers for more technical support.
