All objects emit thermal energy (heat) in the form of electromagnetic radiation in the infrared (IR) spectrum. The hotter the object is, the more intense the infrared radiation emitted. This radiation is, however, outside of the human eye range. IR thermography is used to detect, image, and measure this radiation. By detecting areas of abnormal temperature, IR thermography can diagnose problem areas and their severity.
Modern IR cameras provide detailed photographs indicating each piece of operating equipment's "heat signature." The amount of temperature rise over the normal operating temperature provides a good indicator of the severity of a problem, such as an overload or imbalance, corrosion, or bad connection. This thermal profile, correctly interpreted, can reveal a great deal regarding the operating condition of the equipment being inspected.
Infrared has many applications such as electrical equipment, mechanical systems, and many, many others
Why IR Surveys Are Important
IR surveys are an investment in the safety, productivity, and profitability of a facility. Insurance industry loss statistics indicate that more than 30 percent of all fire losses are electrical in origin, resulting in electrical failures being the single most likely cause for industrial insurance claims. And more important to the small-business owner, even if an electrical failure doesn't cause a fire, it can result in equipment breakdown and productivity loss. In today's increasingly competitive world, even a short-term production loss could result in long-term customer loss.
Experts have recognized the benefits of infrared scanning in fire loss prevention. Section 18-16.5 of the NFPA (National Fire Protection Association) "Recommended Practice for Electrical Equipment Maintenance" states: "Routine infrared inspections of electrical systems should be performed annually. Where warranted by loss experience; installation of new equipment; environmental; operational; or load change condition, more frequent infrared inspections, e.g., quarterly or semiannually, should be performed."
In addition to preventing losses, IR inspections can help to extend equipment life. A 10-degree-C temperature rise over the rated temperature can reduce a motor's life by half and increase energy consumption substantially. As part of a comprehensive maintenance and loss prevention program, regular IR surveys performed by a properly qualified professional can find problems and allow plant management to schedule repairs when it is convenient, eliminating production upsets and unscheduled downtime, as well as extending equipment life and reducing energy consumption.
Many large and small sized corporations have made IR an integral part of their preventive maintenance and loss prevention programs. Most property insurance carriers recommend annual inspections.
Infrared Imaging Allows to See What our Eyes Cannot
How IR Is Performed
Performed on operating equipment and machinery, an IR survey is a nondestructive test that does not interrupt normal business operations. Measurements are made:
⦁ While the plant is operating.
⦁ Without contacting the target object.
⦁ With the equipment under full load.
⦁ From a safe distance from energized electrical equipment, rotating equipment, or equipment in hostile environments.
After the survey is completed, a report is prepared and can be delivered on-site in either electronic format or color print.