Liquid ring vacuum pump with cavitation regulation

摘要

A method for operating a liquid ring vacuum pump employs taking vibration measurements of the pump and comparing the measurements with a prescribed cavitation threshold. In addition, a measurement representing the liquid content in the gas to be conveyed is taken. This measurement is compared with a prescribed threshold. The rotational speed of the liquid ring vacuum pump is reduced if the prescribed cavitation threshold has been exceeded and the liquid content is less than the prescribed threshold. The rotational speed is increased if the prescribed cavitation threshold has been exceeded and the liquid content is greater than the prescribed threshold. A liquid ring vacuum pump is designed for implementing the method. Due to the regulation depending on the oscillations of the pump, the pump can be operated near the cavitation boundary without any risk of damage.

主权项

1. A liquid ring vacuum pump having a gas with a liquid content, said liquid ring pump having a pump housing, and an impeller which is mounted eccentrically in the pump housing and operates at a rotational speed, and a vibration sensor for recording vibrations of the pump, characterized in that the pump comprises a logic module which compares a measured value of the vibration sensor with a predefined cavitation limiting value and which compares a measured value which represents the liquid content of the gas to be delivered with a first limiting value, a control unit being provided to adapt the rotational speed of the pump:
i. the control unit reduces the rotational speed if the predefined cavitation threshold value has been exceeded and the liquid content lies below a predefined limiting value; ii. the control unit increases the rotational speed if the predefined cavitation threshold value has been exceeded and the liquid content lies above the predefined limiting value.