Ten common mistakes in using water pumps that cause damage

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As a device for transporting and pressurizing water sources, the water pump plays an important role in water supply systems. Pumps often experience various faults during use, and most of these faults are caused by improper usage. 01、Overload: Whether it is flow rate, pressure, or speed, operating for an extended period at values that are significantly away from the rated design parameters can increase the load on the pump. For example, a centrifugal pump operating at its full capacity results in higher power consumption, which shortens its lifespan and may even lead to its failure. 02. Difficulty in sucking in the medium: 1. If the liquid level at the inlet is too low, vortices are likely to form, allowing air to be drawn in, which results in cavitation and a decrease in flow rate and head pressure ； 2. The water inlet pipe or inlet is blocked by foreign objects, resulting in a decrease in flow rate and head pressure ； 3. As the temperature of the medium increases, its vaporization pressure rises, the net positive suction head decreases, which results in a reduced suction lift ； 4. The water inlet pipeline is not properly designed (e.g., too many bends in the inlet pipe, or a pipe diameter that is smaller than that of the pump’s inlet); this increases pipeline losses and reduces the margin against cavitation, making cavitation more likely to occur ； 5. An increase in the altitude at which the pump is installed leads to a decrease in atmospheric pressure, which in turn reduces the net positive suction head and results in a lower suction lift. 03、Just closing the valve – the water pump remains powered on. Except for automatic and smart pumps, ordinary water pumps operate continuously with the valve closed, and without any bypass system; as a result, energy is wasted on heating the water, which causes cavitation in the pump, leading to unstable operation or even accidents. 04. The corrosive medium corrodes the flow components, mechanical seals, etc. For example, hydrochloric acid corrodes stainless steel, while hydrofluoric acid corrodes silicon carbide. Note: The corroded surface will exhibit numerous pinholes of varying sizes, resembling the surface of the moon. 05. Abrasive flow of liquids containing solid particles continuously washes the pump chamber, impeller, and other flow-related components, resulting in a reduction in the pump’s flow rate and head capacity as well as a shortened lifespan. Note: In cases of severe abrasion, the abraded surface develops a fish-scale pattern. 06. Pump casing cracking occurs due to blockage at the outlet or excessive inlet pressure, or because low temperatures cause the liquid inside the pump chamber to freeze, resulting in the actual pressure within the pump chamber being much higher than its tolerance limit, and ultimately leading to the cracking of the pump casing. 07. The vibrating water pump is installed on a rigid foundation that lacks vibration damping measures, or the foundation is too weak to provide sufficient strength. The inlet and outlet pipelines lack support, which ultimately results in uneven stress on the unit and restricts the vibration of the pump during operation; the pump keeps \"jumping\" as if it were on a trampoline. 08. Moisture exposure: 1. When land-based pumps are exposed to a humid environment for an extended period, or when the mechanical seal fails, the leaking liquid can splash onto the unsealed parts of the motor. 2. The mechanical seal of the submersible pump fails, there is no sealing for the cable; moisture enters the pump in a humid environment or the cable falls into the pool, allowing liquid to penetrate into the motor chamber. Note: If there is water or condensation inside the motor and the insulation resistance is < 50 megohms, it is considered to be damp. 09. Pump inspections are not carried out regularly, and thus they do not receive enough attention. Inspections and regular maintenance are not done as specified in the manual, seal replacements are also not performed on a timely basis. Iron and aluminum pumps are not repainted, and vibrations are not checked, which leads to the pump developing minor issues that eventually turn into serious problems that cannot be fixed. 10. Poor heat dissipation: 1. Submersible pump motors that operate with their parts exposed above the water surface for dehydration, or those that get stuck in sediment, result in slow heat dissipation from the motor, which can lead to motor burnout. In particular, oil-filled motors are prone to explosions due to poor heat dissipation. 2. Land-based pumps are installed in remote locations or within enclosed cabinets, where fans are unable to circulate the air around them, resulting in poor heat dissipation for the motor.