MYTH: “It is acceptable to use a stinger attached to the vibration sensor.”
TRUTH: Stingers can be attached and used with most vibration sensors. However, stingers are the least desirable method to mount the sensor to the equipment. Stingers reduce the frequency range that can be measured with the attached sensor. Also, it is very difficult to use the same amount of pressure to hold the sensor to the equipment each time. This may further reduce the signal response as well as the consistency and quality of data.
MYTH: “Applying generic overall amplitude values allows the correct trending and identification of equipment faults.”
TRUTH: An overall level is a single number representing the amplitude of a vibration measurement. Overall values can be derived in many different ways. You should be very cautious when assigning generic and/or the same alarm values to your equipment. Similar machines can operate at different vibration levels. The individual characteristics of each machine should be taken into consideration when setting valid alarm levels.
MYTH: “Collecting vibration data quarterly, semiannually, or annually on equipment will identify all equipment defects.”
TRUTH: The collection frequency of vibration data should be determined based on several factors. Some of these factors are equipment load, the operational speed of the equipment, operational frequency, criticality, and more. It is possible to calculate the optimal measurement frequency required to routinely identify equipment defects. Assigning some collection frequency based upon manpower or other means almost always results in equipment failures that were not detected in time or at all by the vibration program.