01-beginning vibration analysis.pdf

8/20/2019 01-Beginning Vibration Analysis.pdf

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Beginning Vibration

Analysiswith

Basic Fundamentals

By: Jack Peters


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Jack D. Peters

Beginning Vibration

2

Introduction

Understanding the basics and fundamentals of vibration analysis arevery important in forming a solid background to analyze problems on

rotating machinery.

Switching between time and frequency is a common tool used for

analysis. Because the frequency spectrum is derived from the data inthe time domain, the relationship between time and frequency is very

important. Units of acceleration, velocity, and displacement are

typical. Additional terms such as peak-peak, peak, and rms. are often

used. Switching units correctly, and keeping terms straight is a must.

As much as possible, this training will follow the criteria as established

by the Vibration Institute.


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Jack D. Peters

Mass & Stiffness

3

Mass & Stiffness

All machines can be broken down

into two specific categories.

Mass & Stiffness

Mass is represented by an object

that wants to move or rotate.

Stiffness is represented by springs

or constraints of that movement.


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Jack D. Peters

Mass & Stiffness

4

Mass & Stiffness

f n = 1 / 2П k/m

Where:

f n = natural frequency (Hz)k = stiffness (lb/in)

m = mass

mass = weight/gravityweight (lb)

gravity (386.1 in/sec2)


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Jack D. Peters

Mass & Stiffness

5

Concept !

f n = 1 / 2П k/m

If k increasesThen f increases

If k decreases

Then f decreases


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Jack D. Peters

Mass & Stiffness

6

Concept !

f n = 1 / 2П k/m

If m increases

Then f decreases

If m decreases

Then f increases


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Jack D. Peters

Spectrum

7

What’s This ?

0.0002

inch

Peak

0

Magnitude

Hz1000 Hz

1


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Jack D. Peters

Spectrum

8

FFT, Frequency Spectrum, Power Spectrum

0.0002

inch

Peak

0

Magnitude

Hz1000 Hz

1


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Jack D. Peters

Spectrum

9

Scaling X & Y

0.0002inch

Peak

0

Magnitude

Hz1000 Hz

1

X

Y


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Jack D. Peters

Spectrum

10

Scaling X & Y

0.0002inch

Peak

0

Magnitude

Hz1000 Hz

1

FREQUENCY

AM

P

L

I

T

U

D

E


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Jack D. Peters

Spectrum

11

Scaling X & Y

0.0002inch

Peak

0

Magnitude

Hz1000 Hz

1

What is it

H

o

w

B

a

d

I

s

I

t


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Jack D. Peters

Time Waveform

12

What’s That ?

0.0004

inch

-0.0004

Real

s7.9960940 s

1


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Jack D. Peters

Time Waveform

13

Time Waveform

0.0004

inch

-0.0004

Real

s7.9960940 s

1


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Jack D. Peters

Time Waveform

14

Scaling X & Y

X

Y

0.0004inch

-0.0004

Real

s7.9960940 s

1


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Jack D. Peters

Time Waveform

15

Scaling X & Y

TIME

A

M

P

L

I

T

U

D

E

0.0004inch

-0.0004

Real

s7.9960940 s

1


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Jack D. Peters

Time Waveform

16

Scaling X & Y

What is it

Ho

w

Ba

d

I

s

I

t

0.0004inch

-0.0004

Real

s7.9960940 s

1


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Jack D. Peters

Time Waveform

17

Scaling X & Y

What is it

Ho

w

Ba

d

I

s

I

t

0.0004inch

-0.0004

Real

s10 s

1


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Jack D. Peters

Time & Frequency

18

Double Trouble

0.0004

inch

-0.0004

Real

s7.9960940 s

1

0.0002

inch

Peak

0

Magnitude

Hz1000 Hz

1


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Jack D. Peters

The X Scale

19

The X Scale


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Jack D. Peters

The X Scale

20

Hertz (Hz)

One Hertz (Hz) is equal to 1 cycle / secondIt is the most common term used in vibration

analysis to describe the frequency of a disturbance.

Never forget the 1 cycle / second relationship !

Traditional vibration analysis quite often expresses

frequency in terms of cycle / minute (cpm). This is

because many pieces of process equipment haverunning speeds related to revolutions / minute (rpm).

60 cpm = 1 cps = 1 Hz


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Jack D. Peters

The X Scale

21

Relationship with Time

The frequency domain is an expression of amplitudeand individual frequencies.

A single frequency can be related to time.

F(Hz) = 1 / T(s)

The inverse of this is also true for a single frequency.

T(s)

= 1 / F(Hz)

Keep in mind that the time domain is an expression

of amplitude and multiple frequencies.


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The X Scale

22

Concept !

If: F = 1/T and T = 1/F

Then: FT = 1


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The X Scale

23

Concept !

FT = 1

If: F increases

Then: T decreases

If: T increasesThen: F decreases


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Jack D. Peters

The X Scale

24

Single Frequency

1

V

rms

0

Magnitude

Hz1000 Hz

Pwr Spec 1

1

V

-1

Real

ms62.469480 s

Time 1

X:55 Hz Y:706.8129 mV

dX:18.18848 ms dY:2.449082 mV

X:27.00806 ms Y:3.579427 mV


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The X Scale

25

Multiple Frequencies

1

Hz1000 Hz

Pwr Spec 1

1 Hz1000 Hz

Pwr Spec 1

1

Hz1000 Hz

Pwr Spec 1

1

Hz1000 Hz

Pwr Spec 1

X:55 Hz Y:706.8129 mV

X:78 Hz Y:706.9236 mV

X:21 Hz Y:706.7825 mV

X:42 Hz Y:706.9266 mV


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The X Scale

26

Multiple Time

1

V

ms62.469480 s

Time 78 1

1

V

ms62.469480 s

Time 21 1

1

V

ms62.469480 s

Time 42 1

1

V

ms62.469480 s

Time 55 1


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The X Scale

27

Real Life Time

4

V

-4

Real

ms62.469480 s

TIME 1

55 + 78 + 21 + 42 = Trouble !


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The X Scale

28

Frequency Spectrum

4

V

-4

Real

ms62.469480 s

TIME 1

1

V

rms

Hz1000 Hz

FREQUENCY 1

X:78 Hz Y:706.9236 mV

X:55 Hz Y:706.8129 mV

X:42 Hz Y:706.9266 mV

X:21 Hz Y:706.7825 mV


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The X Scale

29

The Most Copied Slide in the History of Vibration Analysis !

A m p

l i t u d e

I n p u t T i m e F r e q u e

n c y

T i m e W a v e f o r m S p

e c t r u m


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Jack D. Peters

The X Scale

30

Lines of Resolution

0.0002inch

Peak

0

Magnitude

Hz1000 Hz

1

The FFT alwayshas a defined

number of lines

of resolution.

100, 200, 400,

800, 1600, and

3200 lines are

commonchoices.

This spectrum

has 800 lines, or

the X scale is

broken down into

800 points.


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Jack D. Peters

The X Scale

31

Filter Windows

• Window filters are applied to the timewaveform data to simulate data that

starts and stops at zero.

• They will cause errors in the time

waveform and frequency spectrum.

• We still like window filters !


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Jack D. Peters

The X Scale

32

Window Comparisons


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The X Scale

33

Filter Windows

• Hanning (Frequency)• Flat Top (Amplitude)

• Uniform (No Window)

• Force Exponential

• Force/Expo Set-up

(Frequency Response)

Hanning 16% Amplitude Error

Flat Top 1% Amplitude Error

Window functions courtesy of Agilent “The Fundamentals of Signal Analysis”

Application Note #AN 243


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Jack D. Peters

The X Scale

34

Filter Windows

• Use the Hanning Window for normalvibration monitoring (Frequency)

• Use the Flat Top Window for calibration

and accuracy (Amplitude)

• Use the Uniform Window for bump

testing and resonance checks (NoWindow)


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Jack D. Peters

The X Scale

35

Minimum Derived Hz

The minimum derived frequency is determined by:Frequency Span / Number of Analyzer Lines (data points)

The frequency span is calculated as the ending

frequency minus the starting frequency.

The number of analyzer lines depends on the analyzer

and how the operator has set it up.

Example: 0 - 400 Hz using 800 lines

Answer = (400 - 0) / 800 = 0.5 Hz / Line


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Jack D. Peters

The X Scale

36

Bandwidth

The Bandwidth can be defined by:

(Frequency Span / Analyzer Lines) Window Function

Uniform Window Function = 1.0

Hanning Window Function = 1.5

Flat Top Window Function = 3.5

Example: 0 - 400 Hz using 800 Lines & Hanning Window

Answer = (400 / 800) 1.5 = 0.75 Hz / Line

Note: More discussion

later on window functions for the analyzer !


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Jack D. Peters

The X Scale

37

Resolution

The frequency resolution is defined in the following

manner:

2 (Frequency Span / Analyzer Lines) Window Function

or

Resolution = 2 (Bandwidth)

Example: 0 - 400 Hz using 800 Lines & Hanning Window

Answer = 2 (400 / 800) 1.5 = 1.5 Hz / Line


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Jack D. Peters

The X Scale

38

Using Resolution

The student wishes to measure two frequency

disturbances that are very close together.

Frequency #1 = 29.5 Hz.

Frequency #2 = 30 Hz.

The instructor suggests a hanning window and 800 lines.

What frequency span is required to accurately measure these two frequency disturbances ?


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Jack D. Peters

The X Scale

39

Using Resolution

Resolution = 30 - 29.5 = 0.5 Hz / Line

Resolution = 2 (Bandwidth)

BW = (Frequency Span / Analyzer Lines) Window Function

Resolution = 2 (Frequency Span / 800) 1.5

0.5 = 2 (Frequency Span / 800) 1.5

0.5 = 3 (Frequency Span) / 800

400 = 3 (Frequency Span)

133 Hz = Frequency Span


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Jack D. Peters

The X Scale

40

Data Sampling Time

Data sampling time is the amount of time required to takeone record or sample of data. It is dependent on the

frequency span and the number of analyzer lines being used.

TSample = Nlines / Fspan

Using 400 lines with a 800 Hz frequency span will require:

400 / 800 = 0.5 seconds


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Jack D. Peters

The X Scale

41

Average & Overlap

• Average - On• Overlap Percent - 50%

TR#1 TR#2 TR#3

FFT#1 FFT#2 FFT#3

TR#1

TR#2

TR#3

FFT#1

FFT#2

FFT#3

0% Overlap

50% Overlap

How long will it take for 10

averages at 75% overlap

using a 800 line analyzer anda 200 Hz frequency span?


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The X Scale

42

75% Overlap ?

• 10 Averages• 75% Overlap

• 800 Lines• 200 Hz

Average #1 = 800 / 200

Average #1 = 4 seconds

Average #2 - #10 = (4 x 0.25)

Average #2 - #10 = 1 second

each

Total time = 4 + (1 x 9)

Total time = 13 seconds


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Jack D. Peters

The Y Scale

43

The Y Scale


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The Y Scale

44

Amplitude

The “Y” scale provides the amplitude value for each

signal or frequency.

Default units for the “Y” scale are volts RMS.

Volts is an Engineering Unit (EU).

RMS is one of three suffixes meant to confuse you !

The other two are:

(Peak ) and (Peak - Peak)


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The Y Scale

45

Pk-Pk (Peak - Peak)

1

V

-1

Real

ms62.469480 s

Time 1

2

V

Pk-Pk

0

Magnitude

Hz1000 Hz

Pwr Spec 1

dX:9.094238 ms dY:1.994871 V

X:22.43042 ms Y:-993.8563 mV

X:55 Hz Y:1.999169 V

The Peak - Peak value

is expressed from the

peak to peak amplitude.

The spectrum value

uses the suffix “Pk-Pk”

to denote this.

Th Y S l


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The Y Scale

46

Pk (Peak)

1

V

-1

Real

ms62.469480 s

Time 1

1

V

Peak

0

Magnitude

Hz1000 Hz

Pwr Spec 1

dX:4.516602 ms dY:997.4356 mV

X:27.00806 ms Y:3.579427 mV

X:55 Hz Y:999.5843 mVThe time wave has notchanged. The Peak

value is expressed

from zero to the peak

amplitude.

The spectrum value

uses the suffix “Peak”

to denote this.

The Y Scale


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The Y Scale

47

RMS (Root Mean Square)

1

V

rms

0

Magnitude

Hz1000 Hz

Pwr Spec 1

1

V

-1

Real

ms62.469480 s

Time 1

X:55 Hz Y:706.8129 mV

dX:2.288818 ms dY:709.1976 mV

X:27.00806 ms Y:3.579427 mV

The time wave has

not changed. The

RMS value is

expressed from zeroto 70.7% of the peak

amplitude.

The spectrum value

uses the suffix

“RMS” to denote this.

The Y Scale


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The Y Scale

48

Suffix Comparison

2

V

rms

0

Magnitude

Hz1000 Hz

Pwr Spec 1

2V

Peak

0

Magnitude

Hz1000 Hz

Pwr Spec 1

2V

Pk-Pk

0

Magnitude

Hz1000 Hz

Pwr Spec 1

1

V

-1

Real

ms62.469480 s

Time 1

1

V

-1

Real

ms62.469480 s

Time 1

1

V

-1

Real

ms62.469480 s

Time 1

X:55 Hz Y:706.8129 mV

X:55 Hz Y:999.5843 mV

X:55 Hz Y:1.999169 V

dX:2.288818 ms dY:709.1976 m

X:27.00806 ms Y:3.579427 mV

dX:4.516602 ms dY:997.4356 m

X:27.00806 ms Y:3.579427 mV

dX:9.094238 ms dY:1.994871 V

X:22.43042 ms Y:-993.8563 mV

RMS

Peak

Peak - Peak

The Y Scale


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The Y Scale

49

Changing Suffixes

Many times it is necessary to change between suffixes.

Pk-Pk / 2 = Peak

Peak x 0.707 = RMS

RMS x 1.414 = Peak

Peak x 2 = Pk-Pk

The Y Scale


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The Y Scale

50

Standard Suffixes

Now that we have learned all about the threestandard suffixes that might possibly confuse the

“Y” scale values, what is the standard ?

Vibration Institute:

Displacement = mils Peak - Peak

Velocity = in/s Peak or rms..

Acceleration = g’s Peak or rms..

Note: 1 mil = 0.001 inches

The Y Scale


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The Y Scale

51

Engineering Units (EU)

Engineering units are used to give meaning to the

amplitude of the measurement.

Instead of the default “volts”, it is possible to incorporate

a unit proportional to volts that will have greater

meaning to the user.

Examples: 100 mV / g 20 mV / Pa

1 V / in/s 200 mV / mil

50 mV / psi 10 mV / fpm

33 mV / % 10 mV / V

The Y Scale


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EU’s the Hard Way

Sometimes we forget to use EU’s, or just don’t understand howto set up the analyzer.

There is no immediate need to panic if ????

You know what the EU is for the sensor you are using.Example: An accelerometer outputs 100 mV / g and there is a

10 mV peak in the frequency spectrum.

What is the amplitude in g’s ?

Answer = 10 mV / 100 mV = 0.1 g

The Y Scale


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Jack D. Peters 53

The Big Three EU’s

Acceleration

Velocity

Displacement

The Y Scale


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Converting the Big 3

In many cases we are confronted with Acceleration,Velocity, or Displacement, but are not happy with it.

Maybe we have taken the measurement in

acceleration, but the model calls for displacement.Maybe we have taken the data in displacement, but

the manufacturer quoted the equipment

specifications in velocity.

How do we change between these EU’s ?

The Y Scale


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Jack D. Peters 55

386.1 What ?

1g = 32.2 feet/second2

32.2 feet 12 inches

second2 X foot

386.1 inches/second2

g

The Y Scale


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Go With The Flow I

Acceleration (g’s)

Velocity (inch/s)

Displacement (inch)

x 386.1

÷ 2(Pi)f

÷ 2(Pi)f x 2(Pi)f

x 2(Pi)f

÷ 386.1

The Y Scale


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Jack D. Peters 57

Metric Go With The Flow I

Acceleration (g’s)

Velocity (mm/s)

Displacement (mm)

x 9807

÷ 2(Pi)f

÷ 2(Pi)f x 2(Pi)f

x 2(Pi)f

÷ 9807

The Y Scale


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Go With The Flow II

Peak - Peak

Peak

RMS

÷ 2

x .707x 1.414

x 2

The Y Scale


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Doing the Math Units

0.5g x 386.1 inches

second2

g

2π x 25 cyclessecond

0.5g x 386.1 inches x 1 second

g second2

2π x 25 cycles

0.5 x 386.1 inches

2π x 25 cycles second

cycle

1.23 inches/second

There is a 0.5 g

vibration at 25 Hz.

What is the velocity ?

The Y Scale


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Acceleration - Velocity

Example: Find the equivalent peak velocity for a 25 Hzvibration at 7 mg RMS ?

= (g x 386.1) / (2 Pi x F)

= (0.007 x 386.1) / (6.28 x 25)

= 0.017 inches / second RMS

Answer = 0.017 x 1.414 = 0.024 inches / second Pk

The Y Scale


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Velocity - Displacement

Example: Find the equivalent pk-pk displacement for a25 Hz vibration at 0.024 in/s Pk ?

= Velocity / (2 Pi x F)

= 0.024 / (6.28 x 25)

= 0.000153 inches Pk

Answer = 0.000153 x 2 = 0.000306 inches Pk-Pk

The Y Scale


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Jack D. Peters 62

Acceleration - Displacement

Example: Find the equivalent Pk-Pk displacement for a52 Hz vibration at 15 mg RMS ?

= (g x 386.1) / (2 Pi x F)2

= (0.015 x 386.1) / (6.28 x 52)2

= 0.000054 inches RMS

Answer = (0.000054 x 1.414) 2 = 0.000154 inches Pk-Pk

Sensors


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Jack D. Peters 63

Sensors

Sensors


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Accelerometers

• Integrated CircuitElectronics inside

Industrial

• Charge ModeCharge Amplifier

Test & Measurement

Sensors


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Jack D. Peters 65

Accelerometer Advantages

• Measures casing vibration• Measures absolute motion

• Can integrate to Velocity output

• Easy to mount

• Large range of frequency response

• Available in many configurations

Sensors


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Jack D. Peters 66

Accelerometer Disadvantages

• Does not measure shaft vibration• Sensitive to mounting techniques and

surface conditions

• Difficult to perform calibration check• Double integration to displacement often

causes low frequency noise

• One accelerometer does not fit allapplications

Sensors


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Jack D. Peters 67

Mass & Charge

Mass

Ceramic/QuartzPost

Relative movement

between post &

mass creates shear

in ceramic

producing charge.

Sensors


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Jack D. Peters 68

Accelerometer Parameters

Performance Suited for ApplicationSensitivity (mV/g)Frequency Response of target (f span)

Dynamic Range of target (g level)

Sensors


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Jack D. Peters 69

Mounting the Accelerometer

500 2000 6,500 10,000 15,000 15,000

Hz.

Sensors


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Jack D. Peters 70

Realistic Mounting

Stud

Bees Wax

Adhesive

Magnet

Hand Held

100 1,000 10,000Frequency, Hz

In the real world,mounting might

not be as good as

the manufacturer

had in the lab !

What happened

to the high

frequency ?

Sensors


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Jack D. Peters 71

Mounting Location

Axial

Horizontal

Vertical

Load Zone

Radial

Vertical

Horizontal

Axial

Sensors


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Mounting Location

Load Zone

Radial

Vertical

Horizontal

Axial

Sensors


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Jack D. Peters 73

Accelerometer Alarms

Machine Condition

rms peak

Acceptance of new or repaired equipment < 0.08 < 0.16

Unrestricted operation (normal) < 0.12 < 0.24

Surveillance 0.12 - 0.28 0.24 - 0.7

Unsuitable for Operation > 0.28 > 0.7

Velocity Limit

Note #1: The rms velocity (in/sec) is the band power or

band energy calculated in the frequency spectrum.

Note #2: The peak velocity (in/sec) is the largest positive

or negative peak measured in the time waveform.

Sensors


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Jack D. Peters 74

Proximity Probes

Sensors


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Jack D. Peters 75

Proximity Probe Theory

Driver

Target

Cable

Probe

The tip of the probe broadcasts a radio frequency signal

into the surrounding area as a magnetic field.If a conductive target intercepts the magnetic field, eddy

currents are generated on the surface of the target, and

power is drained from the radio frequency signal.

As the power varies with target movement in the radio

frequency field, the output voltage of the driver alsovaries.

A small dc voltage indicates that the target is close to the

probe tip.

A large dc voltage indicates that the target is far away

from the probe tip.

The variation of dc voltage is the dynamic signal

indicating the vibration or displacement.

Sensors


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Jack D. Peters 76

Output Values

• Typical – 100 mv/mil – 200 mv/mil

• Depends onprobe, cable(length), anddriver.

• Target materialvaries output.

Calibration Examples

• Copper 380 mV/mil

• Aluminum 370 mV/mil

• Brass 330 mV/mil• Tungsten Carbide 290 mV/mil

• Stainless Steel 250 mV/mil

• Steel 4140, 4340 200 mV/mil

Based on typical output sensitivity

of 200 mV/mil.

Sensors


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Jack D. Peters 77

Proximity Probes - Advantages

• Non-contact• Measure shaft dynamic motion

• Measure shaft static position (gap)

• Flat frequency response dc – 1KHz

• Simple calibration

• Suitable for harsh environments

Sensors


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Jack D. Peters 78

Proximity Probes - Disadvantages

• Probe can move (vibrate)• Doesn’t work on all metals

• Plated shafts may give false measurement

• Measures nicks & tool marks in shaft• Must be replaced as a unit (probe, cable &

driver)

• Must have relief at sensing tip fromsurrounding metal

Sensors


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Jack D. Peters 79

Typical Mounting

vertical probe horizontal probeH

V

time

Facing Driver to Driven(independent of rotation)

Sensors


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Looking at Orbits

Vertical for

AmplitudeHorizontal for

Time Base

Sensors


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Jack D. Peters 81

The Orbit Display

i l s

M i l

s

Mils

Sensors


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Jack D. Peters 82

Unbalance

Sensors


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Jack D. Peters 83

Unbalance with Orbit

Sensors


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Misalignment

Sensors


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Misalignment with Orbit

Sensors


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Jack D. Peters 86

And the problem is ?

Sensors

P i it P b Al


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Jack D. Peters 87

Proximity Probe Alarms

Machine Condition

< 3,600 RPM < 10,000 RPM

Normal 0.3 0.2

Surveillance 0.3 - 0.5 0.2 - 0.4

Planned Shutdown 0.5 0.4

Unsuitable for Operation 0.7 0.6

Al lowable R/C

Note #1: R is the relative displacement of the shaft

measured by either probe in mils peak-peak.

Note #2: C is the diametrical clearance (difference between shaft OD and journal ID) measured in mils.

Sensors

A l I t F t E d


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Jack D. Peters 88

Analyzer Input - Front End

• Coupling - AC, DC

• Antialias Filter - On, Off

AC coupling will block the DC voltage.

It creates an amplitude error below 1

Hz. DC coupling has no error below 1

Hz, but the analyzer must range on the

total signal amplitude.

Prevents frequencies that are greater

than span from wrapping around inthe spectrum.

Analyzer Input Capacitor

Blocks DC

AC Coupling Capacitor in DSA

If the antialias filter is turned off, at what

frequency will 175 Hz. appear using a 0 -

100 Hz span, and 800 lines ?

1024/800 = 1.28

100 x 1.28 = 128 Hz175 Hz - 128 Hz = 47 Hz.

128 Hz - 47 Hz = 81 Hz

Sensors

L E d F R


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Jack D. Peters 89

Low End Frequency Response

0.01

V

rms

0.002

Magnitude

Hz250 Hz

Input 1

0.01

V

rms

0

Magnitude

Hz250 Hz

Output 2

2

0

Magnitude

Hz250 Hz

Freq Resp 2:1

1.1

0.9

Magnitude

Hz250 Hz

Coherence 2:1

X:2.8125 Hz Y:984.7542 m

X:500 mHz Y:720.0918 m

X:5.34375 Hz Y:1.000001

To the right is a typical

problem with frequencyresponse at the low end of

the frequency spectrum.

This low end roll off was aresult of AC coupling on

CH #2 of the analyzer.

Values below 2.8 Hz are inerror, and values less than

0.5 Hz should not be used.

Data Collection

D t C ll ti


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Jack D. Peters 90

Data Collection

Data Collection

T R d “I P li ”


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Tape Recorders “Insurance Policy”

Multi-channel

digital audio tape

recorders.

For the

Measurement that can’t get away !

Data Collection

Dynamic Signal Analyzers “Test & Measurement”


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Dynamic Signal Analyzers Test & Measurement

Large PC driven solutions

with multiple channels and

windows based software.

Smaller portable units

with 2 – 4 channel

inputs and firmware

operating systems.

Data Collection

Data Collectors “Rotating Equipment”


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Data Collectors Rotating Equipment

Data Collection

Data Collectors “Rotating Equipment”


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Data Collectors Rotating Equipment

• Route Based• Frequency

Spectrum

• Time Waveform

• Orbits

• Balancing

• Alignment

• Data Analysis• History

• Trending

• Download to PC

• Alarms

• “ Smart” algorithms

Beginning Vibration

Bibliography


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Bibliography

• Eisenmann, Robert Sr. & Eisenmann, Robert Jr., Machinery

Malfunction Diagnosis and Correction, ISBN 0-13-240946-1

• Eshleman, Ronald L., Basic Machinery Vibrations, ISBN 0-

9669500-0-3

• LaRocque, Thomas, Vibration Analysis Design, Selection,

Mounting, and Installation, Application Note, ConnectionTechnology Center

• Agilent Technologies, The Fundamentals of Signal Analysis,

Application note 243

• Agilent Technologies, Effective Machinery Measurements usingDynamic Signal Analyzers, Application note 243-1

Beginning Vibration

Thank You !


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Thank You !

You can find technical papers on

this and other subjects at

www.ctconline.comin the “Technical Resources” section

01-beginning vibration analysis.pdf

Documents