Thermographic Testing Vibrotech Reliability Services Limited

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

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

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

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

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

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

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

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

Electrical Switch Gear Fuse boxes Cable runs Electrical connectors Insulation Transformers

Junction Box

Fan

Fuse Box

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

Transformers Electrical connections Insulators Thermal profile Operating temperature Liquid Level

Refractory Linings Torpedo ladles Boilers Furnaces Exhausts Ducting Kilns

Rotary Kiln - Access Door

Kiln - Refractory Lining

Torpedo Ladle

Steel Carrying Ladle

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

Building Surveys

Moisture/Water Ingress Leaking Roof Bridged Cavity Leaking pipes

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

Vessel Surveys

Flare Stacks

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

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

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

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