Contents
Overview
Other IR Applications
Sample IR Images:
- Hydraulic Oil Coolers
- Crane Gantry House
- Power Turbine Surface Hot Spot
- Power Turbine Exhaust Leak
- Generator Heater
- Crane Motors and Idler Wheels
- DC Hoist Motor Brushes
- Gearbox
- Compressor Leak
- Lube Oil Tank
Overview
Machinery will usually display thermal signatures of various failures and normal operating conditions.
Cooling systems, rotating components, combustion, vibration, electrical current, and other sources of energy will have an effect on the infrared radiation emitted. As with electrical inspections, the load on the equipment and environmental factors such as sun and wind will affect temperature changes.
With both rotating equipment and machinery, infrared thermography is often used to find immediate failures and critical problems. Perhaps an even greater benefit, however, is in trending equipment in conjunction with other maintenance technologies such as vibration analysis, acoustics, and oil analysis. All of these monitoring methods should work together in a comprehensive predictive maintenance program. If the data is gathered and correlated consistently, the cost benefits are phenomenal.
As with all infrared inspections it is also important to understand the theories involved in how infrared radiation works and how heat transfer is affecting the objects in a thermal image. Concepts such as emissivity, thermal reflections, thermal conductivity, and indirect temperature measurement are crucial to the identification and diagnosis of mechanical problems.
1. Hydraulic Oil Coolers
These two hydraulic oil coolers were side-by-side and fed by the same line. The inset cooler is operating normally, with good flow and heat transfer throughout. The inlet is in the bottom left corner of the coolers and the outlet is at the top. You can see that there is not consistent heat transfer in the cooler pictured in the background. Instead, it is just conducting heat at a slower rate away from the warmer oil at the inlet. There blockage, likely at the inlet to this cooler.
You may left-click on the picture for an expanded view.
Table of Contents
2. Crane Gantry House
This fan motor housing is well in excess of 200° C. The windings would be somewhat higher. This is the cooling fan for the electrical gantry house on a large crane. A GPS cable had fallen into the blades, jamming them. During the several minutes required to find and shut off the power source, this motor housing rose in temperature by at least 14° C.
You may left-click on the picture for an expanded view.
Table of Contents
3. Power Turbine Surface Hot Spot
This image shows a hot spot on the surface of a power turbine. With infrared, both quantitative and qualitative data can be collected to identify the thermal signatures of different stages of failure and to calculate the temperatures to determine the criticality.
You may left-click on the picture for an expanded view.
Table of Contents
4. Power Turbine Exhaust Leak
This image shows an exhaust leak on a power turbine near the exhaust cone.
You may left-click on the picture for an expanded view.
Table of Contents
5. Generator Heater
This image does not show a problem. It is, however, clear evidence that the heater in this diesel generator engine is working properly. It is also a good example of both natural convection currents and good thermal focus.
You may left-click on the picture for an expanded view.
Table of Contents
6. Crane Motors and Idler Wheels
Thermography is an excellent trending tool on machinery which can be easily scanned from a distance during normal operation, such as the motors and idler wheels on large gantry cranes.
You may left-click on the picture for an expanded view.
Table of Contents
7. DC Hoist Motor Brushes
The brushes on the lower portion of this image of a DC hoist motor are dirty and worn. The motor cover was removed and the hoist was operated to capture this image.
You may left-click on the picture for an expanded view.
Table of Contents
8. Gearbox
Infrared thermography is used in conjunction with technologies such as acoustical testing, oil testing, and vibration analysis for predictive maintenance of equipment such as gear boxes. When these different methods are used together for trending purposes, safety and reliability is vastly improved.
You may left-click on the picture for an expanded view.
Table of Contents
9. Compressor Leak
The heat from this leaking cover on a compressor is transferring to the area of least energy, which is the nearby instrumentation tubing. The tubing is acting as a heat sink in this case.
You may left-click on the picture for an expanded view.
Table of Contents
10. Lube Oil Tank
The levels and flow of fluids such as lube oil can often be monitored using a thermal imaging system.
You may left-click on the picture for an expanded view.
Table of Contents
Don't miss any of these great application pages!
