DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
Contents of a Course
1.
Introduction
2.
Maintenance Philosophy
3.
Diagnostics Parameters
4.
Fundamentals of Vibrations
5.
Transducer Characteristics
6.
Condition Monitoring Measurements
7.
Data Analysis and Visualisation
8.
Common Malfunctions
9.
Machinery Condition Evaluation
10. Trend Monitoring and Forecasting
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DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
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Bibliography
1. Cholewa W.; Diagnostyka techniczna maszyn. Wyd. Pol. Śl., Gliwice,
1992
2. Cempel C.; Diagnostyka wibroakustyczna maszyn. PWN, Warszawa,
1989
3. Wiśniewski W.: Diagnostyka techniczna wytwórczych urządzeń
energetycznych w Elektrowniach, PWN, 1991
4. Morel J.: Drgania maszyn i diagnostyka ich stanu technicznego, PTDT,
1992
5. R.C.Sr.Eisenmann: Machinery Malfunction Diagnosis and Correction
Vibration Analysis and Troubleshooting for the Process Industries,
Prentice Hall, 1997
6. Mitchell J.S.: An introduction to machinery analysis and monitoring
Penn Well Books, 1993
7. R.Barron: Engineering Condition Monitoring. Practise, Methods and
Applications, Addison_Wesley Pub., 1997
8. Bruel & Kjaer: Application Notes
9. Solartron Instruments: Technical Reports
10. Bentley Nevada: ORBIT magazine
DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
Forms of energy conversion:
-
→
→
→
→
→
→
→
→
chemical
nuclear
combustion
chemical
thermal
kinetic
thermal
vibration
thermal
thermal
thermal
electric
kinetic
vibration
internal
internal
Where the energy conversion occurs ?
Its occurs among the others in different types of rotations machines like:
turbogenerators,
fans,
pumps,
electric engines,
combustion engines.
Most popular ways of energy conversion
nuclear energy
combustion energy
water energy
solar energy
TURBOGENERATORS
electric energy
LIGHTING
ELECTRIC MOTORS
HEATERS
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DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
DIAGNOSTICS
-
4
the idea
“...The identification of a disease on the base of set of symptoms...”
Petit Larousse
Three important words:
Disease – to diagnose one should have a consciousness what it is „disease”
(in machine maintenance we understand disease as a fault or set of faults,
which deteriorate the machine condition and make difficult its proper
functioning)
Symptom – to diagnose one should have appropriate information
(parameters which allow to identify the disease like: vibration, temperature,
stresses, material wear)
Identification – an operation which puts in order a various information to
determine one or more most probable faults
(comparison between the observation and the information gathered in
KNOWLEDGE BASE).
For simple machines analysis of the cause → effect relations.
For complex machines – much more complicated diagnosis.
DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
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Subject areas of the Diagnostic
Diagnostics
Wear
Vibrational
fault diagnosis
stress monitoring
condition estimation
creep monitoring
condition checking
Efficient
process parameters
monitoring
crack propagation
monitoring
trend monitoring
forecasting
* Condition monitoring must be carried out during different stages of machine
operating time
e.g. for turbomachinery:
¾ during constant load:
- most important is monitoring of vibration and efficiency
¾ during load change as well as run-up and rundown:
- most important is monitoring of vibration and wear
DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
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DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
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Stages of Inference Diagnostic Process
Condition estimation
-
checking of actual condition
-
estimation of condition change based on historical data
-
Forecasting of a “lead” time to break-down.
Fault diagnosis
-
Detection of machine malfunction.
-
Localisation of a fault.
-
Diagnosis of fault causes.
-
Estimation of fault development.
Breakdown
Vibration Level of Frequency
Componenet (Frequency Band)
Maintenance needed
at this Vibration Level
Projected
Trend
Maintenance
carried out
Maintenance Engineer
diagnoses fault
& plans maintenance
Fault begins
Normal Running to develop
Level
Warning
(lead time)
Time
Periodic condition Measurements
made by maintenance personnel
Time between Measurements
decreases as fault develops
DIAGNOSTICS OF
ENERGY CONVERSION
PROCESSES
Chapter 1 –INTRODUCTION
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