Changsha Zoomlian Pump Co., Ltd. 长沙中联泵业股份有限公司

language
    language

    How can we prevent the mining multi-stage centrifugal pump from running dry?

    Publication Date:

    2025-10-31

    Author:

    Source:

    Facebook Linkedin Twitter Tumblr Pinterest

    It's common in mines to encounter this situation: just after starting a multi-stage centrifugal pump designed for draining underground water, operators hear unusual noises from the motor, and upon touching the pump casing, they find it’s already overheating. Upon disassembling the pump for inspection, they discover that the impeller has been worn out due to dry running—resulting not only in costly part replacements but also significant delays in the mine’s drainage operations. In fact, dry running doesn’t happen "suddenly"; with proper preventive measures taken in advance, such failures can easily be avoided. In this article, we’ll explore how manufacturers of mining-grade multi-stage pumps are addressing this issue. Changsha Zhonglian Pump Industry The technician will briefly discuss how to prevent cavitation in mining multi-stage centrifugal pumps, for reference by user organizations.

     

     

    First, you need to install a liquid-level monitoring device on the pump. In mining environments, water levels can change rapidly, and relying solely on manual observation of the tank or pool often leads to missed detections. Therefore, it’s recommended to equip the system with either a float-type liquid-level switch or an ultrasonic level sensor, and set an appropriate minimum water-level threshold. Once the water level drops below the pump’s required suction level, the device will automatically cut off the power supply, preventing the pump from running dry. For instance, in underground sumps, when the water level falls to 1 Below the set level, the system triggers a shutdown—much faster than manually running to turn off the pump.

    Secondly, regular inspections of the seals and inlet pipes are essential. A common cause of dry running is air leakage in the inlet pipe, which prevents the pump from drawing water effectively. Each week, check whether the flange gasket at the inlet pipe connection has deteriorated, and inspect the steel pipe for cracks caused by impacts from ore. Additionally, examine the mechanical seal area carefully—if you notice any signs of water seepage, replace the sealing components promptly to prevent air from entering the pump chamber through the seal, which could lead to dry running.

    Before starting the pump, always perform a water-inlet check. Many technicians, looking for convenience, skip this step and start the pump without verifying the liquid level—only to discover later that the water tank is empty. The correct procedure is to first open the pump’s air vent valve before turning on the machine, then fill the pump chamber with water until clear water begins to flow out of the vent valve, after which you should close the valve. At the same time, make sure the suction inlet isn’t blocked by coal slag or gravel, ensuring that water can flow smoothly into the pump body. This way, you’ll prevent the pump from running dry once it’s activated.

    You can also add an idling protection module to the motor. Explosion-proof motors used in mining typically come with overload protection, but during idling, the current may not reach the overload threshold, rendering standard protection ineffective. By installing a dedicated idling protection module, the system can monitor the motor’s vibration frequency and current changes to determine if it’s idling—once idling is detected, 0.5 It can shut down within seconds, preventing the impeller and motor from being damaged due to prolonged idling.

    Finally, regularly maintain the wear-and-tear parts. Impeller 、 Guide Vane After these components wear out, the pump's water suction efficiency will decrease, indirectly increasing the risk of dry running. It is recommended to inspect the impeller for wear every month—especially if the blades have notches or show excessive wear beyond 3 Replace it promptly when it reaches the millimeter mark; at the same time, clean out any impurities inside the pump chamber to prevent foreign objects from jamming the impeller, ensuring the pump's water-handling efficiency and minimizing the risk of dry running at its source.

    Do this well 5 Pointing out this issue can significantly reduce the likelihood of dry-running in mining multi-stage centrifugal pumps. If you encounter any problems during equipment maintenance, feel free to contact the Zoomlion Pump Industry technical team at 15616442288 (WeChat also available). We offer specialized overhaul solutions tailored for mining drainage pumps, helping you minimize downtime due to failures and ensuring stable drainage operations at your mine site.

    Previous:

    The Role of Couplings in Centrifugal Pump Systems

    Next:

    Common Causes of Air Entering Multi-stage Pumps and Solutions

    Related Products