How to Reduce Downtime If Cavitation Happens

Fast Fixes That Often Prevent a Full Shutdown

If you catch cavitation early, these quick changes frequently stabilize the system without major downtime:

• Clean or temporarily remove a plugged suction strainer (then address why it’s plugging).

• Open suction valves fully and remove any “temporary” restrictions added during maintenance.

• Reduce speed/flow to lower NPSHr (many systems cavitate only at the top end of the flow range).

• Shorten suction hose or move the pump closer to the supply (reduces friction losses).

• Increase suction line size (even a short undersized section can starve the inlet).

• Lower the pump elevation or raise liquid level to increase static head.

Permanent System Fixes That Stop Repeat Cavitation (and Repeat Rebuilds)

If cavitation keeps returning, the permanent solution is to redesign suction conditions so the pump has margin under worst-case operation. This is where downtime prevention actually happens.

• Increase NPSHa: raise supply head, lower pump elevation, use a larger/shorter suction line, and reduce fittings/valves on suction.

• Reduce suction friction losses: remove unnecessary elbows, replace restrictive strainers, and avoid reducers right at the inlet.

• Reduce NPSHr: operate closer to best efficiency point (BEP) for centrifugal pumps, reduce speed, or select a pump with lower NPSHr for the duty.

• Control temperature: keep fluid cooler when possible, or treat hot cleaning/upset temperatures as the design case.

• Add a booster pump or change tank configuration for applications that inherently have low inlet pressure.

Monitoring That Prevents “Surprise Cavitation” Downtime

Cavitation is easier to prevent when you measure it. Griswold® recommends taking baseline vibration readings (when the pump is not cavitating) and comparing them over time. That gives you an early-warning indicator before damage escalates. See How to Prevent Pump Cavitation Using NPSHa Calculations.

Practical monitoring also includes: tracking suction pressure, watching tank level, and documenting when cavitation occurs (seasonal temperature shifts, batch changes, minimum-level operation). These patterns often reveal the real cause faster than a tear-down.

Technology Choice Matters When Inlet Conditions Are Poor

Some systems are simply hard on pumps: long suction runs, warm hydrocarbons, low tank pressure, or vapor-prone fluids. In those cases, pump technology can change the downtime story.

If your primary issue is vapor formation and poor inlet conditions, review cavitation guidance such as Blackmer’s® Cavitation Concerns and Simplified Prevention and Wilden’s® Cavitation and Pipe Friction Guide (PDF). These resources help connect suction losses and vapor pressure behavior to repeat failures.

In some applications, teams shift from centrifugal pumps (which are sensitive to vapor and NPSH deficits) to positive displacement or diaphragm technologies that behave more predictably under variable suction conditions. That decision depends on the fluid, viscosity, solids, required flow, and safety constraints.

Next Steps: Get Help Fixing the Cause (Not Just the Symptoms)

If cavitation is repeatedly causing downtime, you may need help evaluating suction conditions, NPSHa margin, and pump selection. Contact the PSG® Store team if you'd like to discuss your application.