Assuming this is an induction motor, the CBM team should be able to take high resolution spectrum data to separate the running speed (1X) peak from pole-passing frequency peaks and the 2X peak from the 2xLF (Line Frequency) peak, assuming that this is a 2 pole motor. The pole passing frequency...
Does your blower have fluid film or rolling element bearings? What kind of vibration transducers are you using to monitor and balance the unit. It is recommended to use a pair of transducers or orthogonally (90 degrees apart) mounted at each radial bearing to quantify the vibration.
The...
I interpret "we fixed the issue by tightening the alignment bolts horizontally. Now the vibration at motor feet reduced to about 2.5 mm/s." as using the jacking bolts to restrain the horizontal motion of the motor. Jacking bolts are used to move the component (motor in this case) while it is...
ADRE is software that is used to collect vibration data from a 408 data acquisition system. Both the hardware (408) and software (ADRE) are Bently Nevada products. Typically, critical turbo-machinery has permanent vibration instrumentation (proximity probes, velocity sensors, accelerometers...
Although technology is necessary, the most important part of your vibration analysis program is the people. They need the proper training and experience (hopefully with some mentorship mixed in) to be successful. Standard vibration training (in the US, there is Vibration Institute, Mobius...
I appreciate the recommendations for preventing this happening again, although my solution will probably be take the flag down when it's windy. I was more interested in the engineering analysis of the situation, out of curiousity.
Been windy the last couple of days and I left my flag up until mother nature decided it needed to be on the ground. I have a flag bracket that was secured to a facia board with three screws. It appears that the force from the wind on the flag caused the screws to loosen/backout, which then...
Lots of good advice provided in this thread, specifically there's no "right decision" and it's up to you (and your family) to make the decision. As others have mentioned, the decrease in commute time could be very beneficial.
Speaking about a leap into the unknown, I certainly feel like that...
Just based upon the description (vertical motor/pump, highest amplitude at the top of the motor (NDE), in one direction) suggests resonance. Recommend performing a bump test or impact test (using a modal hammer) to identify natural frequencies.
Jboggs - I haven't heard this one
"There's an old engineering proverb: "There comes a time in the course of every project when its time to shoot the engineers and start production." I think you have arrived at a similar point in this issue."
but I like it. LPS for you!
Steve
Could it be unbalance associated with the manner in which the unit is uncoupled? An issue with the key/coupling in the uncoupled state? That would fit the characteristics of high radial 1X vibration. The 2X vibration in the axial direction could result from an overhung unbalance condition...
There is not enough information in your post to make an assessment of the situation.
"New turbine tripped on high vibrations during startup."
Did it trip when attempting to transition through a critical speed, at full speed no load, after being synchronized to the grid and at X% of base load...
Pete - A "tiny" bit of disagreement is an understatement.
Maybe try Isidor "Izzy" Kerszenbaum, I know that his expertise is in generators and transformers, but he may be able to help you or direct you to someone else.
http://izzytech.com/blog/staff/
949-230-5986
