Monitoring bearings is certainly a hot topic these days, and there is a bewildering range of equipment available to acomplish this. In our opinion, there are three readily available technologies that can be used to check the state of a bearing. For this overview, we have ignored oil analysis, since we would not class it as an "instant" test.

Ultrasonic monitoring is the equivalent to improving our range of hearing.

The use of ultrasound can be applied to bearings of all speed, including those with extremely low RPM, and can give the first indication of bearing distress or a lack of lubrication. Since you are monitoring at a particular point on the bearing housing, the technique is very localised and it is easy to spot a fault. Much like Vibration Analysis, it is recommended to use the same point on the bearing, at a similiar angle and pressure. Conveyor bearings can also be scanned without contact.

Hand-held instruments, such as the Ultraprobe 9000 and Ultraprobe 10,000, are available, allowing the operator to collect route-based data and store sound files for analysis with software that comes supplied. The Ultraprobe 201 Grease Caddy, which attaches to a grease gun, alerts the user to just how much grease needs applying.

Another advantage to the Ultraprobe line of ultrasonic leak detectors, is that the same instrument, without additional add-ons, can be used to test steam traps, check valves, find leaks and detect electrical arcing in enclosed switchgear panels.

Vibration monitoring is the equivalent to our sense of touch.

This technology works for most bearings abvove 200 RPM. Because a longer wavelength is used, it is possible to detect defects in bearings and other areas such as couplings. This can be an advantage if you have the technical expertise to interpret the results, or a disadvantage in that it can be overly confusing and time consuming. This technology, however, isn't particularly useful for detecting a lack of lubrication, because damage would have already begun to occur. Hand-held units collect route-based data for spectrum analysis.

Thermal imaging is the equivalent to improving our range of sight.

Generally speaking, heat is the last effect to be produced by a bearing. If a bearing is running hot, it probably means it is damaged and needs immediate replacement. Whilst thermal imaging is a great technique for electrical applications, it could also be used in addition to other technologies, such as ultrasound, for bearing monitoring. Particularly suitable applications for bearing monitoring with a thermal imaging camera, like the Flir E-Series, may be things like conveyors, which are non-critical.

Much like ultrasound, thermal imaging also has a wide range of other applications.

Gives first indication of bearing distress, straightforward to use. Can be utilised with vibration analysis data collectors. With the Ultraprobe users hear the sound quality of a bearing as well as monitor amplitude changes on a meter. Requiring only one test point and very little training users learn to test bearings in minutes.

Because of the short wave signal the ultraprobe detects it is easy to separate out closely spaced bearings. Use the Ultraprobe with your current vibration analyser for enhanced diagnostic ability.

Lubrication Monitoring -- A major contributor to bearing failure. Hear your bearings and their proper lubrication LOUD and CLEAR with the Ultraprobe 201 Grease Caddy. Know when to STOP lubricating... With the ULTRASOUND Advantage.

Vibration Monitoring -- Ranges from simple hand held meters to highly sophisticated data collection and analysis systems.

Infrared Monitoring -- Complete thermal images of operating equipment can indicate problem areas. Alternatively laser guided infrared thermometers provide accurate point temperatures on bearings etc.

Should you have any questions, or if you would like to discuss any of this further, then please do not hesitate to get in touch.