INFRARED THERMOGRAPHY
PRESENTED BY BALAKRISHNAN.B
What is infrared thermography
Definition of Infrared Thermography Infrared thermography is equipment or method, which detects infrared energy emitted from object, converts it to temperature, and displays image of temperature distribution. The equipment to be called as infrared thermograph and the method to be called as infrared thermography.
Thermal Imaging - How it works:
A special lens focuses the infrared light emitted by all of the objects in
view. The focused light is scanned by a phased array of infrared-detector elements. The detector elements create a very detailed temperature pattern called a thermogram. It only takes about one-thirtieth of a second for the detector array to obtain the temperature information to make the thermogram. This information is obtained from several thousand points in the field of view of the detector array. The thermogram created by the detector elements is translated into electric impulses. The impulses are sent to a signal-processing unit, a circuit board with a dedicated chip that translates the information from the elements into data for the display. The signal-processing unit sends the information to the display, where it appears as various colors depending on the intensity of the infrared emission. The combination of all the impulses from all of the elements creates the image.
Operation of infrared thermography
What the infrared thermography do
thermograph or a "thermal image" which reveals
components that are overloaded or faulty. Working on the simple principle that faulty components, or poor electrical connections, exhibit readily detectable temperature increases when compared to the ambient temperature profile, IR scanning quickly and easily locates problem areas that can be corrected before failure occurs.
Infrared light
Infrared light can be split into three categories: Near-infrared (near-IR) - Closest to visible light,
near-IR has wavelengths that range from 0.7 to 1.3 microns, or 700 billionths to 1,300 billionths of a meter.
Mid-infrared (mid-IR) - Mid-IR has wavelengths
ranging from 1.3 to 3 microns. Both near-IR and mid-IR are used by a variety of electronic devices, including remote controls.
largest part of the infrared spectrum, thermal-IR has wavelengths ranging from 3 microns to over 30 microns.
Thermal-infrared (thermal-IR) - Occupying the
Thermal Imaging Electrical System
All electrical systems, equipment and components are subject to
deterioration once commissioned. This deterioration may be in many forms, for example, loose or corroded connections and joints, insulation resistance breakdown or worn and pitted parts.
excessive loading of electrical systems and equipment or
phase imbalance of electrical systems may also lead to failure. However, when energized and under load, these faults can become clearly visible with the aid of thermal imaging techniques. this allows for instant fault diagnosis allowing the necessary remedial action to take place at an early stage
Thermal imager use in industrial
Problem: V-Belt pulleys show excessive heating. Recommendations: Inspect belt and pulleys, check alignment and ensure tension is correct. Problem: Center phase, line side showing excessive heating compared to adjacent phases. Recommendations: Disassemble, clean, dress all points, reassemble and set torque to specications
Advantages of thermography
It shows a visual picture so temperatures over a large
area can be compared It is able to find higher temperature components prior to their failure It can be used to measure or observe in areas inaccessible or hazardous for other methods It is a non-destructive test method It can be used to find defects in shafts, pipes, and other metal or plastic parts. It can be used to detect objects in dark areas
Some Uses Of Infrared Thermography
Electrical Inspections
Hot Connections Failing Components Overloaded Circuits Medical Severe Acute Respiratory Syndrome (SARS) Manufacturing Processes Plastics Carpet
Fire
Hot Spots
People Rescue
Animal
Equine Hot Joints Ligaments
Building
Thermal Envelope
Roof Leaks
Military
