The term “pump cavitation” refers to a potentially destructive phenomenon that can occur in many industrial contexts, from the chemical to the pharmaceutical industry, including sectors that deal with water treatment or the management of special fluids such as diathermic oil.
The problem occurs when the static pressure of a liquid falls below its vapour pressure, causing the formation of vapour bubbles within the fluid. These bubbles, carried by the flow of liquid, implode violently when they reach areas of higher pressure, causing internal damage to the pump. If not addressed in a timely manner, the phenomenon of cavitation can result in serious long-term consequences, reducing operational efficiency and accelerating wear of pump components.
Pump cavitation: damage caused, prevention to be implemented and solutions to be adopted
Cavitation, therefore, is essentially the formation and implosion of vapour bubbles in a moving liquid. When the local static pressure drops below the vapour pressure of the liquid, bubbles are created. These vapour bubbles tend to form near the internal surfaces of the pump, where the pressure is lower, and then quickly implode as soon as they come into contact with higher pressure areas.
Such implosion generates shock waves that cause significant erosion, especially on interior surfaces, a process commonly called “pitting.” This mechanical damage can cause the gradual destruction of the internal parts of the pump, drastically reducing its life.
The effect of cavitation is particularly evident in operating machines such as centrifugal pumps, where the speed of the fluid and pressure variations create favourable conditions for its formation. The phenomenon can be very noisy and generate strong vibrations, symptoms of a problem that, if not resolved, will inevitably lead to the pump being compromised.
Cavitation damage on pumps
When we talk about pump cavitation, we can’t overlook the damage that occurs at different levels on the exposed pumps. First of all, the implosion of the vapour bubbles causes erosion of the surfaces, which in the short term can appear in the form of small cavities or craters, but in the long term leads to the complete disintegration of the most stressed components. This degradation compromises the correct operation of the pump, reducing its energy efficiency and its ability to transfer fluid effectively. In the worst cases, the pump can stop completely, causing significant interruptions in production and requiring expensive maintenance or replacement.
A typical example of cavitation damage is found in chemical pumps and water treatment pumps, where vapour bubbles form due to sub-optimal flow management. In such a situation, the operator may notice a drop in pump performance, accompanied by an increase in noise and vibration. If action is not taken promptly, erosion can become so extensive as to compromise the entire machine, forcing its replacement.
The prevention of pump cavitation on magnetic drive pumps and mechanical seal pumps
To mitigate the damage caused by cavitation, CDR Pompe offers advanced solutions that include the adoption of innovative technologies and personalised technical advice for each client. In particular, CDR stands out for the implementation of solutions for both magnetic drive pumps and mechanical seal pumps. By eliminating the need for dynamic seals, magnetic drive pumps reduce the risk of fluid leaks and improve the management of dissolved gases, thus reducing the chances of cavitation. This type of pump is particularly useful in environments where the management of chemical fluids is essential to avoid the risk of hazardous spills.
Mechanical seal pumps, on the other hand, are designed to withstand difficult operating conditions, such as high fluid speeds or critical pressures, making them less susceptible to the phenomenon of cavitation. Thanks to their advanced structure, they can handle conditions that facilitate the onset of cavitation with a lower incidence of damage.
Solutions offered by CDR to prevent cavitation
Among the main solutions that CDR offers to counteract pump cavitation, the use of diamond silicon carbide bushings (RSSiC) is one of the most effective. Thanks to their high resistance to wear and extreme temperatures, these bushings protect the internal surfaces of the pump from erosion caused by the implosion of vapour bubbles. Diamond silicon carbide has been shown to extend the life of the pump, reducing the need for maintenance and long-term operating costs.
For example, in a pump used for transferring high temperature chemicals, the adoption of RSSiC bushings can significantly reduce cavitation damage, while improving the overall efficiency of the system. The result is greater business continuity and a significant reduction in maintenance costs.
How to prevent cavitation: CDR consultancy
To prevent cavitation from occurring, it is essential to configure the system correctly from the beginning. CDR Pompe offers a tailored consultancy service, analysing every detail of our clients’ operating specifications to prevent the onset of the phenomenon. This means carefully considering parameters such as flow rate, operating pressures and the quality of the materials used to ensure that the pump always operates in optimal conditions.
If you would like more information or need assistance on how to prevent pump cavitation, please do not hesitate to contact us. Our team of experts is ready to help you safeguard your systems and optimise the performance of your pumps.