Audio acoustic plant condition monitoring of spiral bevel gearbox

Plant condition monitoring (PCM) is widely used by a variety of industries as part of a condition based maintenance programme. This replaces the previ ous 'schedule' based maintenance programme, in which individual components of a machine are replaced at specified intervals. With PCM the condition of the individual components is monitored, and they are only replaced when th eir performance is deemed unsatisfactory. PCM techniques are often capital and/or labour intensive, and their use limited to critical machines only. T he objective of the present research is to develop a system comprised of mi crophones and accelerometers which is able to screen industrial environment s, such as the hot rolling mill at Corus's Port Talbot plant, for machine f aults. The system would use the minimum number of transducers to remotely s creen the maximum number of machines, but is not required to provide detail ed diagnostic information. To date, an omnidirectional microphone has been used successfully to detect badly damaged gear teeth. The method does not r equire the use of a soundproof enclosure to filter out background noise. A finite element analysis model of the test rig has been created to determine the eigenfrequencies and eigenmodes of the test rig and to improve the und erstanding of the vibration behaviour of the faults.