During a recent cooling tower shaft alignment, using a Fixturlaser XA Alignment System, when we started taking our initial set of measurements the laser beam went slightly off the “S” sensor detector, even in 60 degrees of rotation.
Normally when the laser beam travels off the detector I use the laser beam, to perform the rough alignment, by adjusting the motor while watching the beam to set it halfway back to the center of the detector. The rule of thumb is to adjust the motor’s rear feet when looking at the laser beam striking the “S” detector and adjust the front feet when looking at the laser beam striking the “M” detector.
This method works great but in this case the laser beam only went off the top of the detector slightly so instead of starting with the beam in the center of the detector we simply adjusted it lower on the detector and started from there. The laser beam stayed in the 30mm detector and we used the measurement results to perform the alignment. The “S” Sensor setup and final results can be seen below.
Normal Sensor Set-up
Modified Sensor Set-up
Final Results
About the author:
Richard Talley is the owner of Motor Service Technology in Winston, GA. Motor Service Technology offers machinery alignment, balancing and vibration analysis services throughout the Southeast. Richard has over 25 years experience in the machinery reliability field. He can be reached at motorservicetech@bellsouth.net
