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

language
    language

    Common Issues and Solutions for High-Pressure Multistage Pumps

    Publication Date:

    2025-10-10

    Author:

    Source:

    Facebook Linkedin Twitter Tumblr Pinterest

    Many customers often encounter sudden vibrations, unusual noises, a significant drop in water pressure, or even leakage from the shaft end when operating high-pressure multistage pumps, leading them to hastily call for repair technicians. In fact, many of these issues can actually be identified and resolved by the users themselves—this article explains how. Changsha Zhonglian Pump Industry Just starting with the common ones 3 Let me thoroughly explain the specific causes and practical solutions for these frequently occurring failures—after reading, you’ll have everything clear.

     

    Multi-stage pump

     

    1. After turning on the machine, is there unusual vibration noise, and does your hand feel noticeably numb when touching the pump body?

    This is the most common issue—don’t immediately blame the pump’s quality; chances are, it stems from one of two reasons: First, impeller imbalance—perhaps due to long-term pumping of water containing impurities, causing sand or debris to get stuck in the impeller or leading to localized wear. Second, misalignment of the piping system—during installation, the pump’s flange wasn’t properly aligned with the pipe flange. Keep in mind that high-pressure multistage pumps operate at very high pressures. Centrifugal pump Therefore, the impellers are mostly enclosed. If there are large particles or fibrous materials present, the impeller can easily get stuck.

    The solution is simple: First, shut down the machine and disassemble the impeller, then rinse the blade gaps with clean water. If there are any worn-out notches, replace the impeller with one of the same model. Next, use a level to check the coaxiality between the pump body and the pipeline flange—any deviation must be kept within the specified tolerance. 0.1mm Within this range, simply adjust the gasket until it meets the specifications. Remember to clean the inlet filter weekly as part of your routine maintenance, preventing impurities from entering the pump body.

    2. Insufficient water pressure—does the head fail to reach the design value?

    Some people think it’s due to the wrong model selection, but most of the time, it’s actually caused by “internal blockage” or “sealing failure.” For instance, the flow passages in a multi-stage impeller might get clogged with scale, restricting water flow; or the sealing ring between the impeller and the pump body could wear out, creating a larger gap that allows high-pressure water to leak backward, resulting in pressure loss.

    Troubleshooting steps: Disassemble the pump and inspect the flow passages of each impeller stage, using a stiff brush to remove scale and debris. Then, use feeler gauges to measure the clearance of the sealing rings—any readings exceeding 0.5mm It simply has to be replaced—don't settle for less; after switching to a new one, the head pressure can be restored. 90% That's all. Additionally, every 3 Lubricate the pump shaft with grease once every month to reduce the wear rate of the sealing ring.

    3. Is axle-end leakage, dripping onto the ground, a safety hazard?

    The main issue lies in the mechanical seal: either the sealing surfaces are scratched by impurities, or the cooling system fails to keep up, causing the seal to overheat and age prematurely.

    The handling method involves two steps: First, disassemble the mechanical seal and inspect the dynamic and static ring surfaces for any scratches. If scratches are found, replace the mechanical seal with one of the same specifications. Next, check the cooling water pipes and use a pressure gauge to measure the cooling water pressure, ensuring it remains within the required range. 0.2-0.3MPa Ensure the water flow is smooth to carry away heat. When installing the new mechanical seal, remember to apply a thin layer of grease onto the sealing surfaces to prevent scratches during installation.

    If you encounter the issues mentioned above, following this troubleshooting method should generally resolve them. However, if you run into more complex situations such as motor overload or abnormal current, feel free to contact us at 15616442288 (same number on WeChat) for technical support and repair services.

    Previous:

    Method and Specific Steps for Aligning Horizontal Multistage Pumps

    Next:

    The working principle, advantages, and application areas of high-head centrifugal pumps