Thermographic testing uses infrared cameras to detect differences in surface temperatures that may indicate issues. It allows non-contact inspection of electrical systems, buildings, industrial equipment and processes. Key advantages are that it is non-destructive, fast, and can detect problems like loose connections, moisture ingress, insulation issues from a distance. Proper equipment, operator experience and understanding emissivity are important to get reliable results. A variety of applications are described like evaluating switchgear, transformers, refractory linings, vessels, flares and detecting manufacturing or process faults.

1. Thermographic Testing
Vibrotech
Reliability
Services
Limited

2. What is Thermography?
Infra Red Thermography is a technique for
producing a visible image of invisible (to our eyes)
infra red radiation emitted by objects due to their
thermal conditions

3. Thermography
Objectives of Test
• To detect hot or cold area’s
• To determine absolute temperature
• To view Thermal profiles
• To detect temperature loss

4. Thermography
Infra Red is part of the
Electromagnetic
Spectrum
• It travels in straight lines at
the speed of light
• The useful part is divided
between Short and Long
wavelengths
• Use of the correct
wavelength is essential

5. Test Equipment
• Hand held portable camera
• Battery Powered
• Operating at correct
wavelength
• Range…..-20°c to +1500°c
• Sensitivity…..0.1°c at 30°c
• Real time display
• Image Recording capability

6. Why Thermography?
• Non Contact
• Rapid Scanning
• Data can be recorded in differing formats
• Images produced are comprehensive &
reliable
• Is there a viable alternative?

7. Principles of Operation
• Object radiates infra red radiation
• Temperature difference
• Differences are detected and displayed visually
• Emissivity values must be observed

8. Advantages
• Non Contact
• Non Intrusive
• Can work at a distance
• Fast and Reliable
• Portable
• Convincing Results

9. Limitations
• Non Intrinsically safe
• There must be a temperature difference for
certain surveys
• Operator experience is essential
• Filters may be needed for certain
applications
• Sensitivity and Resolution reduce with
distance and angle of view

10. Electrical
• Switch Gear
• Fuse boxes
• Cable runs
• Electrical connectors
• Insulation
• Transformers

11. Junction Box
22.7°C
43.7°C
25
30
35
40
SP01

12. Fan
18.7°C
37.4°C
20
25
30
35
AR01

13. Fuse Box
23.3°C
38.1°C
25
30
35
LI01

14. Electrical Connections
Used for the detection of;
• Corroded connections
• Slack / loose connectors
• Connectors at too high an
operating temperature
• Hot spots

15. Transformers
• Electrical connections
• Insulators
• Thermal profile
• Operating
temperature
• Liquid Level

16. Refractory Linings
• Torpedo ladles
• Boilers
• Furnaces
• Exhausts
• Ducting
• Kilns

17. Rotary Kiln - Access Door
77.8°C
129.3°C
80
90
100
110
120
SP01
SP02
SP03
SP04
LI01

18. Kiln - Refractory Lining
22.5°C
48.7°C
25
30
35
40
45
SP01
SP02
SP03
22.6°C
58.5°C
30
40
50
SP01
SP02
SP03
LI01
SP04

19. Torpedo Ladle

20. Steel Carrying Ladle

21. Building Surveys
Used to detect,
• Lack of insulation
• Cold air infiltration
Draughts
• Moisture traps
• Hot / warm air escaping
• Structural Integrity
• Heating / Cooling

22. Building Surveys

23. Building Surveys
Moisture/Water Ingress
• Leaking Roof
• Bridged Cavity
• Leaking pipes

24. Refinery & Petro-Chem
• Vessel Surveys
• Blockages
• Defective lagging or
insulation
• Steam traps
• Erosion / Corrosion

25. Vessel Surveys

26. Flare Stacks

27. Process Plant
The above Thermograms show how
Thermography can be used as a very fast and
effective maintenance tool.
– The image on the right has a defective cylinder

28. Process Plant
Thermography may be
used for;
• Corrosion surveys
• Ensuring valve operation
• Leaks
• Blockages

29. Process Plant
• Hot spots
• Cold spots (Cryogenics)
• Damaged or missing
insulation
• Tank levels

30. Miscellaneous
• The detection of
process or
manufacturing faults
• Can be used as a
quality control tool