Selecting, Specifying, and Purchasing Infrared Imagers(requires registration to view)
Buying a thermal imager can be a daunting task for a seasoned thermographer; it can be especially difficult for the less experienced. Because the success of an infrared inspection program is dependent upon the chosen test equipment, it is imperative to select proper equipment. Knowing how to correctly specify and choose proper test equipment can help to avoid a costly purchasing mistake and ensure the success of an infrared inspection program.
Fixed Thermal Imaging Camera Systems for Process Measurement & Control(requires registration to view)
Non-contact temperature measurement has long been used for industrial process monitoring and control. Although thermal imagers can provide more detailed information, their use in fixed process monitoring has been limited due to high cost and technological limitations. Recent advances combined with lower cost have made the use of fixed, high resolution thermal imaging systems a viable solution for a wide variety of process monitoring and control applications. This paper will address the use of thermal imaging for process monitoring and control, the state of current technology, installation considerations, and several application solutions.
State of the art IR-Imager in the near infrared spectral range for monitoring high temperatures in industrial applications are characterized by a number of small measurement ranges. Scenes with a high temperature contrast require several measures switching between these range and result in pictures with under range and saturated parts.
A newly developed high temperature IR-Imager with a spectral range in the near infrared provides for a wide dynamic range by utilizing specialized signal processing. A continuous temperature measurement range from 600°C up to 1500°C is realized with a resolution of 640×480 points and a measuring frequency of 25Hz. Each resulting image contains the full dynamic range and is transmitted via a Fast Ethernet interface in real time.
There exists the demand for a high degree of accuracy in measuring and controlling the temperature of flue-gas in power generation plants that must be maintained within a very narrow range as directed by EPA standards, while still assuring the energy efficiency and production of steam within the boiler and safety of the plant. Conventional contact-type thermocouples come up short when compared to the reliability and accuracy displayed by carefully specified non-contact infrared temperature sensors. Use of thermocouples limits the area being measured to the boiler wall surface areas rather than the centermost points of the boiler where the temperature is significantly higher. Also, coal fired boilers typically tend to accumulate soot and ash deposits, insulating the thermocouples, and falsely indicate lower temperature measurement readings inside the boiler or incinerator.
Both circumstances are less than desirable as they indicate lower than actual temperatures and can lead to refractory and boiler tube damage. Ideally, a balance must be struck that allows the most favorable system performance while still safeguarding all the related components against damage or destruction. A remote sensing infrared detection system that operates in the mid four micron wavelength, CO2 Gas absorption band region offers just such a solution.