Vibration Monitoring & Analysis

Slides:



Advertisements
Similar presentations
Machine Condition Monitoring
Advertisements

Filters and Enveloping - A Practical Discussion -
Gearbox Spectral Components and Monitoring Methods
Vibration Analysis (cont)
AMCA International Technical Seminar 2009 Equipment Vibration Presented by: Bill Howarth, Illinois Blower Inc.
CHAPTER 4: HARMONIC RESPONSE WITH A SINGLE DEGREE OF FREEDOM
Vibration Monitoring and Machine Protection Systems 1010 E. Main St., League City, TX Phone: Fax: /
Presentation outline Product development process: =>Design for Six Sigma =>Advanced modelling tools Practical examples => SKF quiet running bearing.
Lecture 30 November 4, 2013 ECEN 2060 Lecture 30 Fall 2013.
Advances in Condition Monitoring – Linking the Input to the Output Martin Jones Insensys.
Model-based V-I systems: - using your existing electric motors to tell you about your driven equipment’s condition Geoff Walker, Director, Artesis LLP.
Vibration Analysis – Case Study
Basic Vibration Analysis
Accelerometer’s for Wind Turbines Alternative Energy Wind turbines are a growing source of alternative clean energy sources. As individual machines, or.
WELCOME.
Vibration Sensors for Cooling Towers Challenges Cooling towers offer the vibration analyst many challenges in sensor selection, mounting and environmental.
BHEL, POWER SECTOR – TECHNICAL SERVICES (HQ), NOIDA
Vibration Control 1) Control of Excitation Control of Vibration Source. Example: Balancing of Machines 3) Control of System Parameters Change of system.
Dial Indicator 를 이용한 Shaft Alignment 의 이해와 절차
SIGNATURE ANALYSIS Which frequencies exist and what are the relationships to the fundamental exciting frequencies. What are the amplitudes of each peak.
Mechanical Vibrations
Problem Solving Part 2 Resonance.
Typical Steps of field Balancing Illustration with model 907
Presentation On Vibration Analysis
MONITORING AND FAULT DIAGNOSIS OF INDUCTION MOTORS
Vibration & Temperature Sensor. Contents ■ Why monitor vibration? ■ Monitor a wide range of machines ■ Vibration measurements ■ Set alarm levels ■ Mounting.
Rotor Track and Balance
Vibration Monitoring & Machine Protection Systems Copyright 1999, Frank Howard, STI Vibration Monitoring, Inc. League City, Texas USA Reciprocating.
Vibration Monitoring & Machine Protection Systems Cooling Tower Vibration Monitoring.
Where We Go Wrong - With Compressors Dick Hawrelak Presented to ES-317y in 1999 at UWO.
Rotor Track and Balance Only????. Agenda History of Rotor Track and Balance. Vibration Requirements Increasing. Using the Tools You Have. Cost Savings.
Wind, wave and tidal energy DNV serving the energy industry.
Power Generation from Renewable Energy Sources
GML-3 GPRS BASED METER AND LOGGER THREE PHASE METER WITH INBUILT DATA LOGGER © Embuilt Technologies Visit us at Or For.
Pressure and Speed Limits
Vibration Data Collector 911D - Economic, Very-easy-to-use Features: Full automatic measurement Automatic diagnosis of machinery faults by time domain.
Motor Testing (Motor Only)
Smart Rotor Control of Wind Turbines Using Trailing Edge Flaps Matthew A. Lackner and Gijs van Kuik January 6, 2009 Technical University of Delft University.
AIR BEARING SYSTEM.
Prepared by: Marimuthu Gurusamy Combined vibration analysis (velocity and acceleration envelope) for Prediction of rotating equipment (with rolling element.
Vibration in SAG Mill Foundation of Stream 3 - Chronological Sequence & An Update.
Steve’s Handy Guide to Orbits
EWEC 2007, MilanoMartin Geyler 1 Individual Blade Pitch Control Design for Load Reduction on Large Wind Turbines EWEC 2007 Milano, 7-10 May 2007 Martin.
Power Generation from Renewable Energy Sources Fall 2012 Instructor: Xiaodong Chu : Office Tel.:
Advanced Simulation Techniques for the coupled Fatigue and NVH Optimization of Engines. K+P Software, Schönbrunngasse 24, A Graz / Austria Tel.:
Vibration & Temperature Sensor. Contents ■ Why monitor vibration? ■ Health degradation curve ■ Predictive maintenance monitoring ■ Monitor a wide range.
DEMAS ENGINEERING SERVICES LIMITED. The Condition Based Monitoring maintenance Experts Our Vision To be the most sought after provider of high quality,
High Speed Balancing in the Service Industry – Deformed Rotors
LATHE VIBRATIONS ANALYSIS ON SURFACE ROUHHNESS OF MACHINED DETAILS LATHE VIBRATIONS ANALYSIS ON SURFACE ROUHHNESS OF MACHINED DETAILS * Gennady Aryassov,
Bird Strike on Jet Fan. Introduction Modelling of Bird Strike using EUROPLEXUS Full Lagrangian Approach Bird modelled by SPH elements (porous gelatine.
Modern Maintenance. Management
Fluke 805 Vibration Meter Redefining Vibration Screening 1.
Pg 1 AO Wireless Solutions Representantes exclusivos para Colombia de la Línea CSI de EMERSON.
Generator Condition Assessment through EMI Diagnostics Doble Power Services.
Rotor Track and Balance
Beginner's Guide to Machine Vibration
Level 2 Vibration Analysis
Optimum Pump Performance for Process Applications
Overview Focused on trip that took place on February 19, around 4:11 PM. Includes data to help understand the nature of the trip. Roughly 2 minutes prior.
Development of RCP Vibration Monitoring System using Power Line Analysis Method 정 재 천.
Project COMP10: Designing for Blade Aeromechanical Integrity
اندازه گیری جریان سیال.
Efftek Diagnostic Engineers St. James House, Temple Sowerby, Cumbria, CA10 1RS, United Kingdom. +44(0) SIGNATURE ANALYSIS u Which frequencies.
Motor Drive Prof. Ali Keyhani. Modern Variable Speed System A modern variable speed system has four components: 1. Electric Motor 2. Power Converter -
Vibration Monitoring & Analysis. What is Vibration ? It is motion of mechanical parts back and forth from its position of rest /neutral position. Vibration.
………. Your Partner in Condition Monitoring ……….2 Condition monitoring of ball and roller bearings using the patented SPM method (Shock Pulse Method)
SYSTEMS FOR AIRCRAFT PREDICTIVE MAINTENANCE
Vibration Analysis for Industrial
High Speed Balancing in the Service Industry – Deformed Rotors
Achintya Choudhury Bhartiya Skill Development University Jaipur India
Presentation transcript:

Vibration Monitoring & Analysis

Vibration Monitoring What is Vibration ? It is motion of mechanical parts back and forth from its position of rest /neutral position.

Vibration Monitoring What causes Vibration ? Induced Force & Freedom for Movement

Harmful Effects of Excess vibration Vibration Monitoring Harmful Effects of Excess vibration Increased load on BRGs: Reduced BRG Life Higher Forces on Mountings: Foundation Loosening and Damage of Support Structure Increased Stresses of M/c : Risk of fatigue components

Harmful Effects of Excess vibration Vibration Monitoring Harmful Effects of Excess vibration Decreased Equipment efficiency. Reduced Output Quality. Increased Maintenance Cost due to more Component Failures and Unplanned Operations Unsafe Operating Environment

Vibration Monitoring Problem Identifications Unbalance Misalignment Mechanical Looseness Antifriction / Sleeve Bearing Defects Gear Defects

Vibration Monitoring Problem Identifications Belt Defects Impeller / Blade Defects Bent Shaft Electrical Problems Resonance

Vibration Monitoring Fundamental Realities All Machines vibrate. An increase in vibration level is a sign of trouble & amplitude of Vibration depends on the extent of defect in the machinery components Each trouble will create vibration with different characteristics

VIBRATION FUNDAMENTALS 90 Upper Limit Neutral Position 180 TIME Lower Limit Period(T) (1 complete cycle) 270

Characteristics of Vibration Vibration characteristics are Amplitude Frequency Hz or CPM Phase Angle or clock face Displacement Velocity Acceleration

Parameter Selection Frequency sensitivity Displacement <600CPM Velocity 600-60,000CPM Acceleration >60,000CPM Spike Energy/SEE Ultrasonic range

Frequency sensitivity

Vibration Monitoring Displacement Velocity Acceleration

FFT FAST FOURIER TRANSFORM. THE PROCESS OF TRANSFORMING TIME DOMAIN SIGNAL TO FREQUENCY DOMAIN. THE TIME DOMAIN SIGNAL MUST FIRST BE SAMPLED AND DIGITIZED.

Time Domain - overall data is the sum of all exciting and reacting forces Imbalance Rolling Element Bearing Coupling chatter Gearmesh Time Resultant Complex Waveform

Enables precise evaluation of machinery condition and prediction Spectrum Analysis Enables precise evaluation of machinery condition and prediction

Fmax, LINES, AVERAGES. Fmax REPRESENTS THE MAXIMUM FREQUENCY RANGE IN CPM OR HZ TO BE SCANNED BY THE INSTRUMENT. Fmax SHOULD NOT BE SET TOO HIGH SO THAT THE RESOLUTION AND ACCURACY SUFFERS OR IT SHOULD NOT BE TOO LOW SO THAT WE MISS SOME IMPORTANT HIGH FREQUENCIES.

GUIDELINES FOR SETTING Fmax. FOR MACHINES HAVING ANTI-FRICTION BEARINGS:- Fmax = 60 x RPM FOR MACHINES HAVING SLEEVE BEARINGS:- Fmax = 20 x RPM FOR GEAR BOXES:- Fmax = 3.25 x GMF

LINES OF RESOLUTION THE RESOLUTION IS THE NUMBER OF LINES OR CELLS WHICH ARE USED TO CALCULATE AND DISPLAY THE FREQUENCY SPECTRUM. THE BANDWIDTH CAN BE CALCULATED BY DIVIDING Fmax BY THE LINES OF RESOLUTION. THE GREATER THE NUMBER OF LINES , THE BETTER IS THE ACCURACY.

FREQUENCY RESOLUTION = Fmax total lines of resolution Bandwidth = total lines of resolution total lines of resolution lines or bins or cells of resolution Amplitude Fmax Frequency

Spectrum Data Collection Time FFT Calculation Time = Time to calculate FFT from Time Waveform [assuming no overlap processing] (60) ( #FFT Lines) (#Averages) FFT Calculation Time = Frequency Span Where: #FFT = Number of FFT Lines or Bins in Spectrum # Averages = Number of Averages Frequency Span measured in CPM

FFT SPECTRUM

OVERALL VIBRATION Total summation of all the vibration,with no regard to any particular frequency.

OVERALL VIBRATION Overall vibration is the total vibration energy measured within a frequency range. Measuring the “overall” vibration of a machine or component, a rotor in relation to a machine, or the structure of a machine, and comparing the overall measurement to its normal value (norm) indicates the current health of the machine. A higher than normal overall vibration reading indicates that “something” is causing the machine or component to vibrate more.

Overall Vibration Total summation of all the vibration,with no regard to any particular frequency. OA = OA=Overall level of Vibration Spectrum , Ai = Amplitude of each FFT line n = No. of FFT Lines of resolution , NBF= Noise Bandwidth for Window chosen 2 2 2 A1 + A2 + ………………………+An NBF

NOTE: Don’t be concerned about the math, the condition monitoring instrument calculates the value. What’s important to remember is when comparing overall vibration signals, it is imperative that both signals be measured on the same frequency range and with the same scale factors.

What is Phase? The position of a vibrating part at a given instant with reference to a fixed point or another vibrating part. The part of a vibration cycle through which one part or object has moved relative to another part. The unit of phase is degree where one complete cycle of vibration is 360 degrees.

Phase is a measurement, not a processing method Phase is a measurement, not a processing method. Phase measures the angular difference between a known mark on a rotating shaft and the shaft’s vibration signal. This relationship provides valuable information on vibration amplitude levels,shaft orbit, and shaft position and is very useful for balancing and analysis purposes.

Vibration Phase

Additional Illustration on Phase

PHASE AN ILLUSTRATION 32 Micron 30 Micron 10 degrees 10 degrees Shaft centre line moves up and down in a planer fashion

PHASE AN ILLUSTRATION 32 Micron 30 Micron 190 degrees 10 degrees Shaft center line moves up and down in a rocking fashion

MACHINE TRAIN MISALIGNMENT TURBINE G/B HP COMP LP COMP AXIAL PHASE (degrees) 0 5 15 18 198 215 10 12 22 24 210 220 12 10 20 22 208 218 8 6 16 20 200 210 Note: All phase readings corrected for pickup direction

Comparing Overall Levels Across Mounting Interfaces

Phase application C B A A 5 Microns, 10 degrees B 7 Microns, 12 degrees C 25 Microns, 175 degrees Bolt at C is loose

Vibration Analysis of Common Problems

Vibration Analysis Unbalance Amplitude proportional to the amount of unbalance Vibration high normally in radial direction (may be also in axial direction incase of overhung and flexible rotors ). 1* RPM vibration is greater than 80% (normally) of the overall reading.

Vibration Analysis Unbalance Horizontal and vertical 1* RPM amplitude should be nearly same, although it also depends on system rigidity on the particular direction. Other frequency peaks may be less than 5% of the 1*RPM amplitude Phase shift of 90 deg. When sensor moves from horizontal to vertical.

UNBALANCE Operating conditions such as load, flow condition and temperature effect unbalance Balance under normal operating conditions Changes in track and pitch angle of fan blades can result in “Aerodynamic Unbalance”

Typical Spectrum For Unbalance

MISALIGNMENT BIGGEST PROBLEM INITIALLY Operating temperature can affect alignment Machines aligned cold can go out when warm Bases or foundations can settle Grouting can shrink or deteriorate Increases energy demands

MISALIGNMENT Forces shared by driver and driven (not localized) Level of misalignment severity is determined by the machines ability to withstand the misalignment If coupling is stronger than bearing the bearing can fail with little damage to the coupling

Three Types of Misalignment Combination (most common) Angular Parallel or Offset

General Characteristics Of Misalignment Radial vibration is highly directional 1X, 2x, and 3x running speed depending on type and extent of misalignment Angular 1x rpm axial Parallel 2x rpm radial (H & V) Combination 1,2,3x rpm radial and axial

Typical Spectrum for Misalignment

Vibration Analysis Misalignment Angular Misalignment High axial vibration ( Greater than 50% of the radial vibration) 1* , 2*, 3* RPM normally high. 180 deg. Out of phase across the coupling

Angular Misalignment Produces predominant 1x rpm component Marked by 180 degree phase shift across the coupling in the axial direction

Vibration Analysis Misalignment Off-Set Misalignment High Axial vibration. Also shows high radial vibrations. 1*, 2*, 3* RPM high. 2* often larger than 1* In case of severe misalignment, much high harmonics (4* - 8*) or even a whole series of high frequency harmonics will be generated. 180 deg. Out of phase across coupling

Parallel Or Offset Misalignment Produces a predominant 2x rpm peak in the spectrum Marked by 180 degree phase shift across the coupling in the radial direction.

Typical Spectrum for Misalignment

Axial Phase Showing Misalignment

Other Types Of Misalignment

Vibration Analysis Mechanical Looseness Caused by structured looseness / weakness of machine feet, base plate or foundation; also by deteriorated grouting, loose base bolts and distortion of the frame or base. Radial vibration high 2* RPM & 1* RPM dominant 180 deg. Phase differences between mating surfaces which have looseness between them.

Vibration Analysis Mechanical Looseness Caused by structured looseness / weakness of machine feet, base plate or foundation; also by deteriorated grouting, loose base bolts and distortion of the frame or base. Radial vibration high 2* RPM & 1* RPM dominant 180 deg. Phase differences between mating surfaces which have looseness between them.

Looseness Looseness produces 2X RPM Freq.

Vibration Analysis Mechanical Looseness Caused by looseness in bearing housing bolts and cracks in the frame structure. Radial vibration high 2* RPM normally dominant. 0.5*, 1* and 3* RPM may also be present Substantial Phase difference between mating surfaces which have looseness between them

LOOSENESS Not an exciting force Allows exciting frequencies already present to exhibit much higher amplitudes Loss or reduction in normal stiffness Caused by: loose mounting bolts deterioration of grouting cracked welds

Two Types Of Looseness Looseness of Rotating Components Loose Rotors Bearings Loose on the Shaft or in Housing Excessive Sleeve Bearing Clearances Looseness of Support System Loose Mounting Bolts Grouting Deterioration Cracks Poor Support Frame Distortion

Looseness Of Rotating System Rattling condition cause impacts due to excessive clearance in a rolling element or sleeve bearing Impacts cause multiple running speed harmonics to appear in the spectra Identified by: multiple harmonics unstable phase highly directional radial vibration

Typical Spectrum for Looseness of Rotating System

Looseness Of Support System FFT readings show 1x rpm, 2x rpm, and 3x rpm components Structural looseness / weakness will cause high 1xrpm peak in FFT Identified by Highly directional radial vibration Bouncing Taking comparative phase readings across interfaces and look for amplitude variation Typically loose in vertical direction

Looseness Of Support System

Modern Trend in Vibration Technology

Condition Monitoring System Integration WALKAROUND OFF- LINE Condition Monitoring System Integration CENTRALISED PROTECTION DISTRIBUTED CONTINUOUS SURVEILLANCE ON - LINE PERIODIC ON-LINE ANALYSIS NETWORK DCS SOFTWARE PdM TECHNOLOGIES CMMS

Overall Data Acquistion 4-20mA MONITOR THE DCS time waveform DCS OUTPUT

this is what the DCS records Overall Data Trends- this is what the DCS records current value changes over time lo alarm hi alarm The limitation is that it does not adequately reflect changes at higher frequencies which can increase by 100% but only add 1% to the overall energy level

Vibration Analysis transducer time waveform Protection Monitor and / or Data Collector Vibration Spectrum time waveform transducer

Band Alarms, associate with each rotating element frequency bands hi alarm lo alarm

Band Trending, the new way forward lo alarm hi alarm changes over time Trend and alarm the: Machine unbalance Alignment Gear mesh Bearings etc

Emonitor Odyssey: spectrum band alarming though its diagnostic tools feature for both On & Off line gives advanced machinery analysis and reduces False Alarms

EMONITOR Odyssey: Frequency Band Trends Frequency Trend of Single Measurement

DIAGNOSTICS - the advantage of frequency band trending Root cause analysis is a complex machine specific exercise considering all eventualities Expert systems are a one off diagnosis and do not show a trend Frequency band trending is specific to root cause analysis Band alarming also indicates vibration signals that are outside the established norms Trending alignment, unbalance, gear meshing and bearing condition condition is more specific A complex issue simplified without the need of specialist customisation and regular updates

DCS Limitations - Summary We have shown that putting total belief in the DCS vibration trend is highly risky Machinery failures still happen with on-line vibration monitoring with 4-20mA data to the DCS. Most causes are due to higher frequency signals swamped by the overall levels. Advanced machinery protection through Frequency Band Trending and Alarming - more specific than an Expert system. The latest S/w based Analysers incorporates Narrow Band Alarming. They offer machinery protection and narrow band alarming. A lower cost solution is periodic manual Data Collection.

ESHAPE: Modal analysis using phase for advanced diagnosis and better understanding of system response

On line Vibration and other monitors Innovative, fully-digital design Exceeds API 670 specification Widely-used system Fully field programmable Low installation cost ModBus protocol

TYPICAL APPLICATION

POWER PLANT INTEGRATION DCS OPERATIONS ENGINEERING ODYSSEY SERVER DATA LOGGER VIBRATION ANALYSER FS HP LP GEN EX BFP ID BFP FD CWP PA TURBINE SUPERVISORY STATOR END WINDING GATEWAY TO CMMS AUXILIARIES

Plant Integration with LAN or WAN DCS ENGINEERING ODYSSEY CLIENT SERVER VIBRATION ANALYSER ETHERNET CONTROL ROOM No 1 CONTROL ROOM No 2 CONTROL ROOM No 3 FS HP LP GEN EX FS HP LP GEN EX FS HP LP GEN EX GATEWAY TO CMMS ANURAKSHAN TG 1 TG 2 TG 3

NETWORKING THE INFORATION - LAN / WAN e.g. RIHAND TALCHER PLANT OPERATIONS VINDHYACHAL NOIDA HQ CM CELL GATEWAY TO CMMS ANURAKSHAN KAYAMKULAM UNCHAHAR

Hyperlink to equipment Using PlantLink Vibration Trend Plot Digital Picture of Plant Hyperlink to equipment Hierarchy Automatic E-Mail notification on Equipment Alarm Status Click on Measurement Label to link to plots or other views.

Information however you want it !

X-Window Screen Captures

Scenario of Instruments &Sensors & Probes Velocity sensors are made in India Accelerometers range over 150 types standard Low frequency High temperature (Gas Turbines) Special application Eddy current probes - comprehensive range Others available for process measurement

Vibration Datacollectors Many vendors Select on ‘Fitness for Purpose’ Intrinsic Safety Dust & Moisture proof Diagnostic Capability