The thermal image of the target is different from the visible image of the target. It is not a visible image that human eyes can see, but an image of surface temperature distribution. Infrared thermal imaging makes it impossible for human eyes to directly see the surface temperature distribution of the object, and becomes a visible thermal image representing the surface temperature distribution of the target. All objects whose temperature is above absolute zero (-273℃) will continuously emit thermal infrared rays. Infrared (or thermal radiation) is the most extensive radiation in nature, and it also has two important characteristics:
(1) The thermal radiation energy of an object is directly related to the surface temperature of the object. This characteristic of thermal radiation enables people to use it to measure the temperature and analyze the thermal state of objects without contact, thus providing important detection means and diagnostic tools for industrial production, energy saving and environmental protection.
(2) The atmosphere and smoke clouds absorb visible light and near infrared rays, but are transparent to thermal infrared rays of 3~5 microns and 8~ 14 microns. Therefore, these two bands are called "atmospheric windows" of thermal infrared rays. Using these two windows, people can clearly observe the situation ahead in the completely dark night or in the battlefield with dense smoke. Because of this feature, thermal infrared imaging technology provides advanced night vision equipment in the military, and installs all-weather forward-looking systems for aircraft, ships and tanks. These systems have played a very important role in modern wars.
With the deepening of people's understanding of it, the application of infrared thermal imager is more and more extensive: it can detect the poor contact and overheated mechanical parts of electrical equipment very quickly to avoid serious short circuit and fire. For all devices that can be directly seen, infrared thermal imaging products can determine the thermal hazards of all connection points. For those parts that cannot be directly seen due to occlusion, we can find their thermal hidden dangers according to the heat conduction to external parts. In this case, the traditional method has no choice but to disassemble, inspect and clean the joint. Infrared thermal imaging products are irreplaceable for the operation test of circuit breakers, conductors, buses and other components. Infrared thermal imaging products can easily detect loop overload or three-phase load imbalance.
In the field of infrared thermal image prediction and maintenance, infrared thermal imager is used to check all electrical equipment and distribution systems, including high-voltage contactors, fuse panels, main power circuit breaker panels, contactors and all distribution lines, motors, transformers, etc. , to ensure that all operating electrical equipment does not have potential thermal hazards, and effectively prevent accidents such as fire and shutdown. The following are some facilities that infrared thermal imaging products need to check:
1. Various electrical equipment: hidden dangers such as loose joints or poor contact, unbalanced load, overload and overheating can be found. The potential effects of these hidden dangers are arc, short circuit, combustion and fire.
2. Transformer: The hidden dangers that can be found are loose joint, overheated bushing, poor contact (tap changer), overload, unbalanced three-phase load and blocked cooling pipe. Its effects are arc, short circuit, combustion and fire.
3. Motors and generators: The hidden dangers that can be found are excessive bearing temperature, unbalanced load, short circuit or open circuit of windings, heating of carbon brushes, slip rings and slip rings, overload and overheating, and blockage of cooling pipes. Its influence is that the faulty bearing will damage the iron core or winding coil; Defective carbon brushes can damage slip rings and slip rings, and then damage winding coils. It may also cause harm to the driving target.
4. Electrical equipment maintenance inspection, roof leak detection, energy saving inspection, environmental protection inspection, security and theft prevention, forest fire prevention, nondestructive testing, quality control, medical inspection and so on are also very beneficial.
The main applications in scientific research field include: automobile research and development-injection molding, mold temperature control, brake disc, engine piston, electronic circuit design, baking paint; Motor and electronics industry-printed circuit board thermal distribution design, product reliability test, electronic component temperature test, notebook computer heat dissipation test, micro-component test; Wind tunnel experiment of engine combustion test: Target characteristic analysis; Testing of composite materials; Building thermal insulation and humidity detection; Study on heat conduction; Animal and plant ecological research; Mould temperature measurement; Metal fusion welding research: surface/ocean heat distribution research, etc.