Pump Vibration Troubleshooting 0511
description
Transcript of Pump Vibration Troubleshooting 0511
![Page 1: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/1.jpg)
Piedmont Chapter Pump Vibration Troubleshooting
by William D. Marscher, P.E.President & Technical Director
Mechanical Solutions, Inc. www.mechsol.com
Whippany NJ
May 13, 2011
![Page 2: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/2.jpg)
Piedmont Chapter
Open Impeller
Shrouded Impeller
The Centrifugal Pump (End Suction)
Suction
Discharge
Impeller Shaft
Casing
Seal
Flow
VaneShroud
Hub
![Page 3: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/3.jpg)
Piedmont Chapter
Impeller rotation versus the volute tongue
Volute Tongue
Discharge Nozzle
Impeller
![Page 4: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/4.jpg)
Piedmont Chapter
Potential for Cavitation from Pressure Depression at Impeller Eye
No Cavitation
Cavitation
![Page 5: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/5.jpg)
Piedmont Chapter
Time (msec) =>
Microphone SPL 85dB
Inboard Pressure +/-150 psi pk
Outboard Pressure +/-150 psi pk
Inboard Accel on Suction Wall +/- 300 G pk
Cavitation Eventv
Scope Traces of Cavitation Event
![Page 6: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/6.jpg)
Piedmont Chapter
Axially Split Case Dbl. Suction Pump
• 180 degree “drip pocket” allows bearing hsg and stuffing box to flex downward due to pressure pulsations, e.g. at 1x or vane pass
• Double suction impeller typically equalizes thrust side-to-side, but at off-design is prone to axial shuttling
• Suction recirc & cav have been issues
![Page 7: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/7.jpg)
Piedmont Chapter
Boiler Feedwater Ring-Section Pumps
“Donut” Pump with Balance Disk
• 180 Less robust than barrel pump, but fewer Fnproblems.
• Designs where thrust disk totally replaces oil lubricated thrust bearing have encountered rub and binding problems during process upsets
![Page 8: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/8.jpg)
Piedmont Chapter
Hero or Enemy? The Thrust Balancing “Disk”
Can have rubs at start-up or during severe process transients, may permit “axial shutting”.
![Page 9: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/9.jpg)
Piedmont Chapter
Pacific BFI Barrel Pump
Barrel Pump with Balance Drum and
Stiff Shaft
• 180 degree “drip pocket” allows bearing hsg Fn near vane pass
• Pedestals weaken with age, structural modes drift into 1xRPM resonance
• Diffuser “strong-back” plates can resonate at vane pass
![Page 10: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/10.jpg)
Piedmont Chapter
Pacific RLIJ
Barrel Pump with Balance Drum, and
Thin Shaft
• Rotor critical speeds sensitive to LomakinEffect and therefore wear ring & drum clearances
• Pedestals weaken with age, structural modes drift into 1xRPM resonance
![Page 11: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/11.jpg)
Piedmont Chapter
Ingersoll-Rand C
Barrel Pump with Balance Disk
• Balance disk is theoretically prone to “control system” phasing instabilities, causing axial shuttling
• Pedestals weaken with age, structural modes drift into 1xRPM resonance
![Page 12: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/12.jpg)
Piedmont Chapter
Worthington WNC
Barrel Pump with Composite Balance
Drum/ Disk
• Balance disk portion may have Ax shuttling
• 180 degree “drip pocket” bearing hsgs have Fn’snear vane pass
• Pedestals weaken with age, structural modes drift into 1xRPM Fn
• Develops rotating stall easily at lower flows
• Design is particularly prone to thermal differential growth top v. bottom causing rotor binding/ rubs
![Page 13: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/13.jpg)
Piedmont Chapter
Axial Split Case Pumps: e.g. Bingham MSD
Axially Split Case Issues:
• Acoustics in x-over
• Top casing half “humps, allowing interstage jet leakage
• Axial shutting at off-design conditions
• High sensitivity of 1st
bend mode to center bushing clearance
![Page 14: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/14.jpg)
Piedmont ChapterPumps for Wastewater Applications
• Excitation of structural natural frequencies– 1X, 2X, Vane Pass
• Packing vs. mechanical seals• Material selection
– ‘Wear’ parts – rings, etc.– ‘Non-Wear’ parts – casings and impellers
• Vertical with intermediate shafting• Submersible
– Wet pit– Dry pit
![Page 15: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/15.jpg)
Piedmont Chapter
Chemical & Pharmaceutical Process Pumps
• Nozzle Loads– Distortion– Stress in non-metallic pumps
• Bearings – low precision– Affect on rotor behavior
• Baseplates– Flexibility
• Seals– Nozzle loads effect on mechanical seals– Packing – over-tightening
• Product lubricated bearings in mag drive and canned motor pumps
![Page 16: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/16.jpg)
Piedmont Chapter
Slurry Pumps
• Similar issues to process pumps, distortion due to nozzle loads is less
• Material selection and specification– Abrasive pumpage– Special coatings and liners
![Page 17: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/17.jpg)
Piedmont Chapter
Vertical Turbine Pump (VTP) Issues:
• Above ground “Reed Freq”
• VFD as a “shaker”
• Lineshaft is “violin string”
• Shaft enclosure tube Fn’s
• Disch nozzle loose joints
• Sump vortices or odd flows
• Column piping acoustics
![Page 18: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/18.jpg)
Piedmont Chapter
Vertical Pump Shaft Thrust Effects
![Page 19: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/19.jpg)
Piedmont Chapter
The “Concept” of Imbalance
![Page 20: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/20.jpg)
Piedmont Chapter
Vibration Problem No. 1:
1x Running Speed
![Page 21: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/21.jpg)
Piedmont Chapter
What Is Resonance?
![Page 22: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/22.jpg)
Piedmont Chapter
Natural FrequencyVibration & Phase vs. Frequency
![Page 23: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/23.jpg)
Piedmont Chapter
Shaft Response to Imbalance
![Page 24: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/24.jpg)
Piedmont Chapter
Shaft Response to Imbalance
![Page 25: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/25.jpg)
Piedmont Chapter
Balance: Single vs. Two Plane
![Page 26: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/26.jpg)
Piedmont Chapter Angular Misalignment
![Page 27: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/27.jpg)
Piedmont Chapter Offset Misalignment
![Page 28: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/28.jpg)
Piedmont Chapter
Vibration Problem No. 2:
1x & 2x .Running Speed
![Page 29: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/29.jpg)
Piedmont Chapter
Observing Alignment Continuously with “Dodd Bars”
![Page 30: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/30.jpg)
Piedmont Chapter
High Energy Density Equipment Alignment Limits
Speed (rpm)
0 1800 3600 10000 20000
Offset, hub-to-hub, mils
1.5
1.0
0.5
0
![Page 31: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/31.jpg)
Piedmont Chapter
Flow Through Elbows(Courtesy Cheng Fluid Systems, Inc.)
![Page 32: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/32.jpg)
Piedmont Chapter Stationary Piping Load Sources
![Page 33: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/33.jpg)
Piedmont Chapter
Piping Acoustic Natural Frequencies
![Page 34: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/34.jpg)
Piedmont Chapter
“Lomakin Effect” in Centrifugal Pumps
![Page 35: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/35.jpg)
Piedmont Chapter
Concept of the “Wet Critical Speed
![Page 36: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/36.jpg)
Piedmont Chapter
Lomakin Effect
![Page 37: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/37.jpg)
Piedmont Chapter
Lomakin Result:Critical Speeds Shift Up
![Page 38: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/38.jpg)
Piedmont Chapter
Approximate Calculation of Lomakin Stiffness
R= Radius
L= Length
C= Radial . clearance
P=Pressure . drop
= fric factor
![Page 39: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/39.jpg)
Piedmont Chapter
Some Key Issues in Lomakin Effect Strength:
![Page 40: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/40.jpg)
Piedmont Chapter
Wild Cards: Swirl & Grooving
![Page 41: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/41.jpg)
Piedmont Chapter
Impeller Radial Support Forces:
Sulzer/ EPRI Tests
/x /x
![Page 42: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/42.jpg)
Piedmont Chapter
Some Typical Exciting Frequencies
![Page 43: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/43.jpg)
Piedmont Chapter
Rolling Element Bearing Parameters
![Page 44: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/44.jpg)
Piedmont Chapter
Rolling Element Bearing Frequencies
-
+
![Page 45: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/45.jpg)
Piedmont Chapter
Lateral Excitation Forces (Sulzer)
![Page 46: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/46.jpg)
Piedmont Chapter
Vibration Problem No. 3:High Vane Pass
![Page 47: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/47.jpg)
Piedmont Chapter
Vibration Problem No. 4:High Harmonics of Run Speed
![Page 48: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/48.jpg)
Piedmont Chapter
Marked-up Copy of Pump Curves
![Page 49: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/49.jpg)
Piedmont Chapter
Flow Rate and the “Angle-of-Attack”
![Page 50: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/50.jpg)
Piedmont Chapter
Vane Stalling at Low Flows
![Page 51: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/51.jpg)
Piedmont Chapter
Example of Stalled Blade
![Page 52: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/52.jpg)
Piedmont Chapter
Onset of Internal RecirculationDischarge Recirculation
Suction
![Page 53: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/53.jpg)
Piedmont Chapter
Vibration & Pulsation vs. Flowrate
![Page 54: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/54.jpg)
Piedmont Chapter
An Unexpected Hydraulic Problem:
Rotating Stall
![Page 55: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/55.jpg)
Piedmont Chapter
Four Stage High Speed Boiler Feed Pump
![Page 56: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/56.jpg)
Piedmont Chapter
Rotating Stall Pulsation Spectrum
![Page 57: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/57.jpg)
Piedmont Chapter
Stall Vibration vs. Speed
![Page 58: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/58.jpg)
Piedmont Chapter
Vibration Problem No. 5:Subsynchronous (below 1x)
![Page 59: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/59.jpg)
Piedmont Chapter
![Page 60: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/60.jpg)
Piedmont Chapter
Rotor Dynamics
Critical Speeds & Mode Shapes
Forced Response
Stability
![Page 61: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/61.jpg)
Piedmont Chapter
Rotordynamics Is Best Evaluated by Computer
![Page 62: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/62.jpg)
Piedmont Chapter
Typical Rotor Vibr. Response vs. Speed Exhibits Several Natural Frequencies
![Page 63: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/63.jpg)
Piedmont Chapter
Avoiding Resonance w/ Campbell Diagram
![Page 64: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/64.jpg)
Piedmont Chapter
Rotordynamic Critical Speed Map
![Page 65: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/65.jpg)
Piedmont Chapter
Forward vs. Backward Precession
![Page 66: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/66.jpg)
Piedmont Chapter
Typical Torsional Critical Speeds and Worst Case Excitations
x2/POLES
![Page 67: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/67.jpg)
Piedmont Chapter
Typical Vibration Problems
![Page 68: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/68.jpg)
Piedmont Chapter
Instrumentation Options
![Page 69: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/69.jpg)
Piedmont Chapter
Converting Vibration vs. Time to Vibr vs. f with “FFT”: Fast Fourier Transform
![Page 70: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/70.jpg)
Piedmont Chapter
Meaning of RMS vs. Peak Vibration
![Page 71: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/71.jpg)
Piedmont Chapter
Vibration Measure Numbers
![Page 72: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/72.jpg)
Piedmont Chapter
Vibration Measurement Format
![Page 73: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/73.jpg)
Piedmont Chapter
Housing vs. Shaft Vibration:Which Should Be Measured?
![Page 74: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/74.jpg)
Piedmont ChapterNatural Frequency
![Page 75: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/75.jpg)
Piedmont Chapter
Approximating Natural Frequency
![Page 76: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/76.jpg)
Piedmont Chapter
Vibration “Mode Shapes”
![Page 77: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/77.jpg)
Piedmont Chapter
Finding Nat. Freq. Resonances with a “Waterfall” Plot of Stacked FFT’s from Test
![Page 78: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/78.jpg)
Piedmont Chapter
Approximate Identification of Natural Frequencies
![Page 79: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/79.jpg)
Piedmont Chapter
A Modal Field Test In-Progress on an Operating Pump
![Page 80: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/80.jpg)
Piedmont Chapter
Short Force Application Excites Wide Frequency Band
![Page 81: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/81.jpg)
Piedmont Chapter
Principle of Time Averaging
![Page 82: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/82.jpg)
Piedmont Chapter
Rotor Impact Testing Case History
![Page 83: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/83.jpg)
Piedmont Chapter 14 Stage Axially Split Case Pump
![Page 84: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/84.jpg)
Piedmont Chapter
Time Averaging Field Example: Watch the Harmonics Disappear
In the End, Natural Frequencies Are Clear
![Page 85: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/85.jpg)
Piedmont Chapter
Impact Test
Rotordynamic Result
Critical Speeds of 14 Stage Pump
![Page 86: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/86.jpg)
Piedmont Chapter
First Critical Speed, Dbl. Suction SS Pump
![Page 87: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/87.jpg)
Piedmont Chapter
Sources of Damaging Forces in Centrifugal Pumps
![Page 88: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/88.jpg)
Piedmont Chapter
Typical Failures in Centrifugal Pumps
![Page 89: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/89.jpg)
Piedmont Chapter
Risk of Accepting Bad vs. Risk of Rejecting Good
![Page 90: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/90.jpg)
Piedmont Chapter
Stuffing Box & Bearing Skew Case Histories
![Page 91: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/91.jpg)
Piedmont Chapter
Cartridge Pump Seal Rub Example
![Page 92: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/92.jpg)
Piedmont Chapter
Vibration Problem #6: Repeating
Impacts
![Page 93: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/93.jpg)
Piedmont Chapter
Double Suction Pump “Breathing” Tilts Stuffing Boxes
![Page 94: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/94.jpg)
Piedmont Chapter
FEA Model of Twisting Pump Bearing Housing
![Page 95: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/95.jpg)
Piedmont Chapter
Vertical Pump Failure Case Histories
![Page 96: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/96.jpg)
Piedmont Chapter
Typical Structural Vibrations of VTP’s
![Page 97: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/97.jpg)
Piedmont Chapter
Six Vertical Pumps on Platform, with Column Exposed to Air
![Page 98: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/98.jpg)
Piedmont Chapter______ ___________
|||||
Vertical Pump Column Vibration with & without Water in Column
1xN 1xN
|
With Water Without Water
![Page 99: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/99.jpg)
Piedmont Chapter
Multistage Pump Inboard Bearing Chronic Failure
Case History
![Page 100: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/100.jpg)
Piedmont Chapter
Pump with Inboard Bearing Failures
![Page 101: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/101.jpg)
Piedmont Chapter
Shaft Orbits of Problem Pump
![Page 102: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/102.jpg)
Piedmont Chapter
Vibration Spectra for Problem Pump
![Page 103: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/103.jpg)
Piedmont Chapter
Impact Test Results Showing Shaft Critical Speed at 5280 rpm
![Page 104: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/104.jpg)
Piedmont Chapter
“What If” Analysis for Problem Pump
![Page 105: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/105.jpg)
Piedmont Chapter
Bearing Groove Change from 0.040 in. Deep to 0.010 in. Deep
Vibration decreased a factor of ten
![Page 106: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/106.jpg)
Piedmont Chapter
Vibration Spectrum After Bearing Fix
![Page 107: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/107.jpg)
Piedmont Chapter
Use of Dynamic Absorbersin Constant Speed Equipment to Decrease Vibration Motion
![Page 108: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/108.jpg)
Piedmont Chapter
Dynamic Absorber Design- Vertical Pump/Motor
![Page 109: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/109.jpg)
Piedmont Chapter
Effect of Dynamic Absorber on Vibration
![Page 110: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/110.jpg)
Piedmont Chapter
Gear Box Noise & Wear Problem
![Page 111: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/111.jpg)
Piedmont Chapter
![Page 112: Pump Vibration Troubleshooting 0511](https://reader034.fdocuments.in/reader034/viewer/2022042422/55cf99c8550346d0339f20e0/html5/thumbnails/112.jpg)
Piedmont Chapter
Conclusions
1.There’s More to Pump and System Vibrations than You Might Expect
2.Keys to Success: Knowledge, Experience, the Right Tools
3.Good Condition-Based Methods & Instrumentation Are Getting Better