Cavitation poses a significant challenge for engineers and pump system operators. Unfortunately, the causes of cavitation can be hard to identify—proposing significant damage to the pump equipment and system performance. But is this detrimental occurrence avoidable?
What is Cavitation?
Cavitation occurs when vapor pockets form rapidly inside the process fluid before imploding. These implosions send shock waves throughout the system and can cause significant damage to impellers, piping, casing, and other pump system equipment. When left ignored, cavitation will cause shutdowns and production delays for repairs and damaged part replacements. It will also hinder the performance of the pump system itself, leading to loss of suction pressure, vibration, or other challenging conditions.
When cavitation happens, your pump system will not perform efficiently and your equipment will not last as long. These are certainly problems any engineer or operator would prefer to avoid at all costs.
How to Prevent Pump Cavitation
Below are a few installation, maintenance, and troubleshooting tips you can utilize to avoid cavitation in your pump’s piping system. Or, if cavitation does occur, you’ll know what you can do to correct the problem(s).
- NPSH Calculations
Calculating the Net Positive Suction Head (NPSH) of the pump system can help you prevent cavitation. All centrifugal pumps have a set amount of NPSH that they require (NPSHr). Make sure the system consistently has a proper level of NPSH available (NPSHa) that is higher than the NPSHr. This can be factored in during equipment selection and system design process to ensure cavitation is not a concern.
- Evaluate Suction Piping and system
If the suction side piping, valves, and strainers are all sized properly then the chances of having cavitation are slim. Using the same size suction pipe as the inlet to the pump is NOT a guarantee the piping is sized properly. One must pay attention to critical factors like liquid viscosity, liquid temperature, tank liquid levels, tank venting, suction side filters/strainers, and avoiding suction side elbows/90s.
- Specialized Equipment
Not all pumps are designed to handle all fluids and flow rates. Select the right equipment and consider installing specialized accessories, custom design features, coatings, and monitoring systems.
- Pump Installation Location
Install the pump as close as possible to the liquid supply tank. The farther away the pump is from the liquid source the more likely the pump will experience caviation. Also, placing the pump as close to the ground as possible or raising the tank above the pump will help prevent caviation.
- Pump System Improvements
In many cases, cavitation occurs when the wrong pump is being used or when the system isn’t optimized for the specific fluid application. The system should be designed, configured, and customized for the application at hand. Installation needs to be precise. The pump system should be monitored constantly to recognize potential cavitation issues before they happen. Lastly, a sound maintenance plan is required to keep the equipment running right and prevent problems like cavitation from occurring.
If you are experiencing cavitation or you need a pump system to handle a very specific fluid processing application, contact DXP Pacific today. Let us help you select the right equipment, custom system engineering, installation, training, maintenance, or repairs. Our expert team will show you how to make cavitation a non-issue.