What is Infrared Thermography?
Infrared thermography can help your business minimize downtime, avoid costly repairs and improve safety.
Infrared thermography is crucial for both condition-monitoring tasks and predictive maintenance plans. This non-destructive testing process measures the amount of heat (thermal radiation) flowing to, from, and through the tested component.
Infrared thermography utilizes an infrared camera to detect the amount of heat and energy disbursed by rotating electromechanical equipment like motors, pumps, fans and other components as they operate. Since the infrared (IR) wavelengths are shorter than the human eye can see, the camera converts the wavelengths into a viewable image with relative temperature readings.
In addition to mapping temperature levels and variances, infrared thermography is highly effective in determining corrosion damage, delamination, voids, and other flaws not visible to an equipment inspector’s naked eye. However, for IR to work effectively, a sufficient difference between the surroundings and the component being tested.
Where Can Infrared Thermography Be Used?
Unlike some other testing procedures, infrared thermography can determine asset conditions across several types of infrastructure essential to companies involved in the manufacturing, distribution, and processing industries.
Electrical Systems
Infrared thermography can quickly identify overloaded circuits and faulty connections by their higher heat signature. The most common causes for increased heat include excessive electrical resistance, load imbalance, and improperly sized components. With infrared thermography, these issues can be found and scheduled for maintenance or repairs before they can fail and bring your production line to a standstill.
Mechanical Systems
Motors and other rotating assemblies are especially susceptible to excessive heat created by the friction of moving parts. For mechanical applications, infrared is especially helpful in locating worn bearings and the need for increased lubrication. Thermography provides real-time data which can give an advanced warning of potential problems and confirmation of sustained damage.
Fluid Systems
Infrared thermography lets facility teams quickly check any line for blockages, temperature fluctuations, and missing insulation. Heat exchangers, valves, and storage tanks can be quickly scanned for proper operation and fluid levels.
Electric Motor Testing
While a complete motor testing program includes offline and online testing, infrared thermography can be especially helpful for online testing of your current.
- Power quality
- Rotor health
- Power circuit
- Stator condition
- Winding insulation
Infrared allows techs to test the equipment online and use the data to determine needed maintenance, repair, or replacement before a critical failure occurs.
Benefits of Infrared Thermography
Infrared thermography is a safe practice for inspectors since the surveys are conducted with minimal contact between the inspectors and running equipment. The portability of the infrared thermography equipment allows scanning of large areas while providing valuable data unavailable via other conventional testing methods.
Identifying potential problems before a component fails can prevent unexpected shutdowns and expensive replacement costs. Infrared thermography testing provides the best ROI for owners, managers, and facility management teams. Several recent studies suggest that infrared thermography testing combined with timely equipment repairs can give an ROI of five to ten times the cost of the testing program.
Infrared Terminology
If you’re not familiar with infrared thermography yet, here is a short list of the jargon used, along with their definitions.
Reflectance: Refers to the amount of light (not heat) reflected from a material’s surface.
Transmittance: Refers to the ability of a material to transmit thermal energy (heat) from the tested component to the infrared camera.
Emissivity: Refers to the ability of a material to emit infrared energy. This score is typically expressed as a number between 0 and 1 where a perfect mirror surface scores a 0, and a blackbody scores 1.
For example, a material with an emissivity score of 0.85 absorbs and emits 85% of infrared radiation, while reflecting 15% of the surrounding radiation.
The next two terms are closely related and are commonly used interchangeably, although they have different definitions.
Temperature: Describes the average energy of molecular motion of an object and is not affected by the object’s size. Temperature can be measured directly unlike heat.
Heat: Describes the total energy of molecular motion of a specific object and is affected the object’s size. Heat can also describe how thermal energy transfer from object to another, or its surroundings.
Heat Transfer: Refers to the movement of thermal energy moving from a hotter region to a colder one. There are three ways heat transfer can occur.
- Convection is the heat transfer occurring through gases and liquids.
- Radiation is the heat transfer occurring through electromagnetic waves.
- Conduction is the heat transfer occurring between solids.
