Thermography techniques

Baumann, P. Phosphor thermography technique in hypersonic blowdown wind tunnel feasibility study with pinpoint measurement. Rech. Aerospace 1993, 5, 29. 

Applications involving the reduction-to-practice of pulsed thermography techniques include an Electric Power Research Institute (EPRI) project to detect the extent of erosion/corrosion damage in power generation boiler tubes. The material in this section is reprinted with permission from EPRI. 

This leads to the development of active thermography techniques, where a controlled heat source such as a halogen lamp and acoustic transducer is used (Chatterjee et al. 2011). A laser thermography technique is relatively new in the field of active thermography and uses a high-power laser as a heat source. Compared to a... 

Active thermography is a contactless NDE technique that consists in the detection of infrared emission after the transient thermal excitation of the inspected structure. 

A comprehensive program that includes predictive maintenance techniques to monitor and analyze critical machines, equipment, and systems in a typical plant. Techniques include vibration analysis, ultrasonics, thermography, tribology, process monitoring, visual inspection, and other non-destructive analysis methods. 

These techniques include (1) vibration monitoring (2) thermography, (3) tribology, (4) process parameters, (5) visual inspection and (5) other nondestructive testing techniques. This chapter will provide a description of each of the techniques that should be included in a full capabilities predictive maintenance program for typical plants. 

Thermography is a predictive maintenance technique that can be used to monitor the condition of plant machinery, structures and systems. It uses instrumentation designed to monitor the emission of infrared energy, i.e. temperature, to determine their operating condition. By detecting thermal anomalies, i.e. areas that are hotter or colder than they should be, an experienced surveyor can locate and define incipient problems within the plant. 

Inclusion of thermography into a predictive maintenance program will enable you to monitor the thermal efficiency of critical process systems that rely on heat transfer or retention electrical equipment and other parameters that will improve both the reliability and efficiency of plant systems. Infrared techniques can be used to detect problems in a variety of plant systems and equipment, including electrical switchgear, gearboxes, electrical substations, transmissions, circuit breaker panels, motors, building envelopes, bearings, steam lines, and process systems that rely on heat retention or transfer. 

Reliable micro-scale measurement and control of the temperature are required in developing thermal micro-devices. Available measurement techniques can be largely classified into contact and non-contact groups. While the resistance thermometer, thermocouples, thermodiodes, and thermotransistors measure temperature at specific points in contact with them, infrared thermography, thermochromic liquid crystals (TLC), and temperature-sensitive fluorescent dyes cover the whole temperature field (Yoo 2006). 

Stage I Parallel and quasi-parallel analytical techniques IR thermography Photoacoustic analysis Photothermal deflection... 

Thermography using heat radiation enables the observation of temperature differences, thermal emissivity, or thermal conduction of the studied object. This technique is mainly used in the examination of monuments [16]. 

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