sure. what I mean is the motor is bolted to the wall, not the floor. and it's bolted to a flimsy mounting plate that has no real jacking bolts so they can't get the proper tension on the belt for one thing.
I would very much like to figure out a new mounting arrangement for the millwrights if...
thank you very much Franko. Millwrights replaced shaft bearings and belt and the readings are even worse at the motor and shaft bearings. also the motor mounting bolts are actually in the horizontal direction! I should have noticed that last time.
I notice robinson doesn't differentiate between...
Excellent idea jmack. What I have is a "balancing kit" with the ability to take phase measurements and an instruction manual with the Commtest instrument vb1000-T.
OK then. Will the phase measurement tell me how much the sheave is wobbling, that is, rotating through an angle...
hi micjk,
I would very much like to understand what you are asking about pulley misalignment and the axial direction and driver versus driven but I don't. Can you please rephrase and try again? What do you mean driver being the driven and vice-versa?
-nisqually
Franko,
Thanks. I will try out the vibe calculator. I wish it could tell me how to lower the vibe on my equipment :)
Did you look at the picture? How do you use a flexible coupling with a belt driven fan? I thought that is for direct coupled fan/motors. I am new at this. Please explain. A link...
Most likely the fan RPM *is* showing up at the motor.
Motor RPM must be 3600 RPM. Belt is at an angle. Here are all readings at the biggest spike.
H V A
Bearing 1(RPM) .748(3750) .171(3600)
Bearing 2(RPM) .569(3750) .215(3600)...
Greetings -
- pulley
fan - -------------|||---shaft
- /\ /\ |
- brg4 brg3 | belt
|
motor|||pulley
What could cause high horizontal readings on the motor bearings? Pulley...
Fred- thanks much for the compliment on the diagram.
JMack- thanks for the tip on interpersonal relations. i need all the help i can get in that area. have you ever worked for a company that has more v.p's than electricians? have you ever worked at a company where education is not valued...
Final -
Bearing#3 .09H .04V .08A
Bearing#4 .12H .03V .08A
Original -
Bearing#3 .18H .13V
Bearing#4 .31H .04V
These are all in/sec 0-to-peak.
No axial recored in original.
Thanks everyone for all the info. We finished the job last week. The end result was lower vibration readings.
Bearing#3 .09H .04V .08A
Bearing#4 .12H .03V .08A
These are in/sec 0-to-peak.
No chance of bringing in someone. Months of training hoops to get thru just to be able to walk into that...
Hi. No this wasn't a student noticing a bump. I was called into this at the last minute. I was told the fan needed balancing because of a keyway problem. This fan is used to ventilate large tank of nuclear waste. I'm not sure what maintenance activity had been done previously but probably no...
-
- pulley
fan - -------------|||---shaft (with unfilled keyway
- /\ /\ | on this side of pulley)
- brg4 brg3 | belt
|
motor|||pulley
OK. Tell me. Is a picture really worth a thousand...
Hi. I just came back from the field. The situation is the keyway extends all the way to the end of the shaft so there is missing material (not extra material like I thought). What is usually done in this case? I did take vibration readings in the horizontal and vertical directions on both shaft...
With little more info. maybe I can get a little more help? the equipment is a horizontal fan (shaft) driven (via belts/sheaves) by a 5HP motor (that's five, pretty small I guess). I believe the motor speed is about 3600 RPM. I'm not sure of the fan shaft speed until the test but it is less than...
Hello,
I am in need of assistance. I am very new at this. I am told a larger than normal key on a shaft must be balanced with some mass added on the other side of the shaft. That's fine. But we are supposed to use a vibration test to verify the shaft is balanced properly. I assume the location...
