What to do about fan vibration during startup?
If correction weights are applied during startup, then vibration is minimal during startup, but quite severe once the temperature differential is corrected. The solution is an auxiliary drive that rotates the fan rotor slowly during shutdown periods, ensuring uniform fan temperature.
What can be done about vibration in fan bearing?
One solution is a proximity probe, which is applicable in sleeve-type bearing installations. A proximity probe reaches down through the bearing housing and into the bearing liner where it directly measures the radial movement of the shaft. High levels of vibration can be detected before any damage occurs.
What causes vibration in a stiff support system?
A stiff-support system with low vibration sensitivity can make it difficult to monitor the health of the machine using the bearing housing as the point of reference. It would be possible for rotor cracks to cause great centrifugal force without significant vibration registering in the bearing housing.
Is it possible to measure the vibration of a fan?
High levels of vibration can be detected before any damage occurs. Proximity probes are not practical with roller bearings. Vibration can be measured effectively on the housing instead. Occasionally, it may be necessary to mount a fan on structural steel instead of a concrete foundation at grade level.
Which is the best way to assess vibration?
The assessment of vibration requires the use of an overall frequency-weighted value for each axis (x, y and z directions). This overall value is assessed against the preferred value for the relevant axis. An alternative to using frequency-weighted values is presented as a simplified screening technique in Appendix A.
What is the current technical guideline for vibration?
Evaluation of human exposure to vibration in buildings(1–80 Hz). BS 6472 (current and former versions) has guided the Department of Environment and Conservation’s (DEC) evaluation of vibration since the mid-1980s. Thus, this technical guideline does not represent a change in policy approach.
Which is the most important vibration problem in engineering?
5.4 Forced vibration of damped, single degree of freedom, linear spring mass systems. Finally, we solve the most important vibration problems of all. In engineering practice, we are almost invariably interested in predicting the response of a structure or mechanical system to external forcing.
What to do if your iPhone randomly vibrates?
Now, however, let’s return to what you can do if your iPhone seems to be vibrating randomly with no desire on your part to have it happen. With any iPhone problem, it makes sense to try the most obvious solution first. In this case, you should check to see if the vibration feature has been activated.