​​Pump Vibration Monitoring

• Shut down a clarifier, lift station, or process line
• Force emergency bypass or discharge, increasing environmental and safety risks
• Drive up overtime and rush-repair costs
• Shorten the life of motors, couplings, seals, and bearings

• Run to failure → reacting after the fact
• Calendar-based PM → doing work whether it’s needed or not
• Condition-based / predictive maintenance → using real vibration data to decide when to intervene
• Not every pump needs continuous monitoring—but pumps with high consequence of failure, difficult access, or critical impact on flow or quality usually do.

• Velocity sensors or accelerometers mounted on the pump or motor casing
• Measuring vibration in units such as mm/s or inches per second (ips) for velocity, or g’s for acceleration
• Tracking both:
• Overall vibration level (how “rough” the machine is running)
• Frequency content (which speeds or harmonics are causing the vibration)

• Motor inboard and outboard bearings
• Pump inboard and outboard bearings
• Casing or bearing housings near points of highest vibration response

• The motor and upper bearing housings
• The support structure or pedestal, where vibration from the submerged stages is transmitted

• Piping vibration near the pump discharge or suction, where hydraulic issues or resonance can show up
• Nearby structures or baseplates when looseness or soft foot is suspected

• Running speed (1×) is the pump’s operating speed; many faults show up here or at multiples of this frequency.
• Imbalance typically shows up as elevated vibration at 1× running speed.
• Misalignment and looseness often create vibration at 1×, 2×, and higher harmonics.
• Bearing defects tend to excite higher-frequency bands and grow gradually over time.

• A single overall vibration value (e.g., in ips)
• Warnings and trips when vibration exceeds configured thresholds

Pump vibration monitoring is most valuable when it points you to specific, fixable problems.

What it is: Uneven distribution of mass around the rotating assembly.

Elevated vibration at 1× running speed, often growing over time.

• Clean or flush the pump to remove deposits
• Balance or replace the impeller
• Inspect for erosion or damage that may indicate process issues

What it is: The motor and pump shafts are not properly aligned at the coupling.

• Skid movement or settling
• Inconsistent alignment practices after motor replacement
• Thermal growth not accounted for during alignment

Elevated vibration at 1× and often 2× running speed, sometimes accompanied by heat at bearings or couplings.

• Perform laser alignment and correct angular/offset misalignment
• Check baseplates, shims, and foundation for soft foot or distortion
• Review alignment procedures and standards

What it is: Degradation of pump or motor bearings due to wear, contamination, or poor lubrication.

• Over- or under-lubrication
• Contaminated grease or oil
• Misalignment, imbalance, or excessive loads

• Increasing overall vibration
• Elevated levels in higher-frequency bands associated with bearing defect frequencies
• Often a gradual upward trend rather than a sudden spike

• Plan bearing change-out before catastrophic failure
• Correct underlying causes (alignment, lubrication intervals, contamination, overhung loads)
• Review lubrication type, quantity, and schedule

What it is: Mechanical looseness in the pump, motor, baseplate, or foundation.

• Loose anchor bolts or hold-downs
• Inadequate grouting or cracked foundations
• Soft foot conditions at motor feet

• Broadband vibration across multiple frequencies
• Changes in vibration following maintenance, moves, or piping changes

• Tighten and torque fasteners to spec
• Re-grout or repair foundations and baseplates
• Diagnose and correct soft foot conditions

What it is: Formation and collapse of vapor bubbles in the pumped liquid, causing noise, vibration, and damage.

• Insufficient Net Positive Suction Head (NPSH)
• Low suction levels, clogged strainers, or restrictions
• Over-throttled valves or improper control schemes

• Distinct “chattering” or “gravel” sound
• High-frequency vibration content that may increase as cavitation worsens
• Often accompanied by flow or pressure fluctuations

• Adjust operating conditions (suction head, valve positions)
• Clean strainers and suction piping
• Review pump selection, NPSH margin, and control strategy

Not every pump needs the same level of monitoring. The right approach depends on criticality, cost, and risk.

What it is: A technician uses a handheld vibration instrument on a scheduled route (e.g., monthly or quarterly).

• Non-critical pumps with low consequence of failure
• Facilities that already have vibration tools and skilled staff
• Verifying the health of pumps that operate intermittently

• Misses short-lived or rapidly developing fault conditions
• Depends heavily on the consistency and skill of the technician
• Provides limited real-time protection between routes

What it is: Fixed vibration sensors installed permanently on pumps, feeding data to transmitters, local monitors, or control systems.

• Critical pumps that must not fail unexpectedly
• Pumps in hard-to-access locations (wet wells, galleries, confined spaces)
• 24/7 operations where a brief shutdown has high cost

• Real-time alarms for sudden changes or unsafe vibration levels
• Trend data that shows the progression of faults
• Integration with SCADA, PLCs, or DCS for unified plant views

• Tier 1 – Critical pumps:
  High consequence of failure, safety/environment impact, or costly downtime → Continuous online monitoring.
• Tier 2 – Important but not critical pumps:
  Noticeable impact when down but with workarounds → Periodic vibration routes plus visual/operational checks.
• Tier 3 – Non-critical pumps:
  Low-cost, easily replaced, low-consequence → Basic PM, no dedicated vibration monitoring (or spot checks as needed).

• 4–20 mA vibration sensors for simple integration into PLC, DCS, or SCADA systems
• Sensors designed for:
• Constant-duty operation in pump galleries and outdoor stations
• Wet, dusty, or dirty environments around wastewater and slurry systems
• Reliable operation on both motors and pump bearing housings

• Pre-engineered or custom monitoring panels
• Systems that monitor vibration on several pumps and motors
• Panels that include:
• Power supplies, fusing, terminals
• Alarm lights or horn outputs
• Interfaces to plant control systems

• Water and wastewater pump stations with high humidity, washdown, and splash zones
• Mining and mineral processing areas with dust, slurry splash, and heavy-duty cycles
• Outdoor booster and transfer stations exposed to temperature extremes

• List pumps and assign a criticality score based on:
• Safety and environmental impact
• Production impact and downtime cost
• Repair/replacement cost and lead time
• Designate Tier 1, Tier 2, and Tier 3 pumps.

For pumps selected for monitoring:

• Record vibration at normal operating conditions (flow, pressure, speed).
• Capture baseline data shortly after installation or overhaul.

• Decide which pumps receive:
• Fixed 4–20 mA vibration sensors
• Route-based periodic checks
• Determine how data will be used:
• Direct to PLC/DCS/SCADA for alarming and trending
• Into dedicated Metrix monitors or panels
• Integrated with existing condition-monitoring systems

Ensure compatibility with your control system standards and I/O capacity.

• Set vibration warning and trip thresholds for each monitored pump or use standard guidelines as a starting point.
• Document what happens at each level:
• Warning → schedule inspection or bearing check
• Trip → automatic shutdown and root-cause investigation

This prevents “alarm fatigue” and ensures clear, consistent responses.

• Combine vibration with:
• Bearing or winding temperature
• Suction and discharge pressure
• Flow and motor power

Examples:

• Rising vibration + dropping suction pressure → possible cavitation or suction restriction
• Rising vibration + rising temperature → bearing/lubrication issue
• Stable vibration + falling flow → process or hydraulic issue downstream

• Review vibration trends on critical pumps monthly or quarterly.
• Use the data to:
• Adjust PM schedules
• Improve alignment and installation practices
• Inform future pump and baseplate specifications
• Plan spares for bearings, seals, and critical components

Over time, you’ll build a clearer picture of which pumps are chronic offenders and where design or process changes may be justified.

• Select suitable Metrix vibration sensors and transmitters for each pump
• Recommend sensor mounting locations and wiring practices
• Design panels for single or multi-pump stations that fit your standards

• Sensor installation best practices and loop checks
• Verifying vibration signal integrity and alarms
• Training on how to interpret alarms and basic trends for pump health

• Supply replacement sensors and transmitters
• Help add vibration monitoring to new pumps, blowers, and fans
• Assist in integrating more assets into your predictive maintenance strategy

• Call Clipper Controls:(844) 880-2469
• Or send us a message: visit the Clipper Controls contact page