Speed monitoring of centrifugal pumps
Speed monitoring of centrifugal pumps is an important part of ensuring their normal operation and efficient operation. The speed of a centrifugal pump refers to the number of revolutions of the rotor (such as the impeller) inside the pump body per unit time, usually in revolutions per minute (r/min). Correct speed monitoring is of great significance for maintaining pump performance, preventing overload, reducing vibration and noise, and extending the service life of the pump.
Importance of speed monitoring
The speed of a centrifugal pump is closely related to its performance, head, flow rate, and power. In practical applications, according to different working conditions, the speed of the centrifugal pump may need to be adjusted to achieve the best operating effect. Therefore, real-time monitoring of the speed of the centrifugal pump can ensure that the pump operates within the set speed range and avoid problems such as performance degradation, increased energy consumption, or equipment damage caused by excessively high or low speeds.
Methods of speed monitoring
Using a tachometer:
The tachometer is a commonly used measuring tool that can directly measure the speed of a centrifugal pump. When in use, place the sensor head of the tachometer on the pump body close to the rotor, and measure the speed by sensing the magnetic field or vibration generated by the rotation of the rotor.
The tachometer has the characteristics of intuitive readings and accurate measurements, and is suitable for speed monitoring under various working conditions.
Install the speed sensor:
Install the speed sensor on the centrifugal pump, convert the speed signal into an electrical signal or a digital signal through the sensor, and transmit it to the monitoring system for real-time display and recording.
The speed sensor can realize remote monitoring and automatic alarm functions. When the speed exceeds the set range, the system can automatically issue an alarm to remind the operator to take timely measures.
Inverter control:
For centrifugal pumps driven by motors, the speed of the motor can be controlled by the inverter, thereby achieving precise control of the pump speed.
The inverter can automatically adjust the output frequency and voltage of the motor according to the set speed curve or actual working conditions, so that the pump body runs at a constant speed.
Precautions
When monitoring the speed, the accuracy and reliability of the measuring tool should be ensured to avoid misjudgment caused by measurement errors.
Maintain and calibrate the speed monitoring equipment regularly to ensure that it is in good working condition.
According to the actual working conditions and needs of the centrifugal pump, reasonably set the speed range and alarm threshold to ensure the effectiveness and timeliness of the monitoring system.
