Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. nisqually

    Want to lower HIGH horiz vibe readings !

    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...
  2. nisqually

    Want to lower HIGH horiz vibe readings !

    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...
  3. nisqually

    Want to lower HIGH horiz vibe readings !

    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...
  4. nisqually

    Want to lower HIGH horiz vibe readings !

    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
  5. nisqually

    Want to lower HIGH horiz vibe readings !

    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...
  6. nisqually

    Want to lower HIGH horiz vibe readings !

    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)...
  7. nisqually

    Want to lower HIGH horiz vibe readings !

    Greetings - - pulley fan - -------------|||---shaft - /\ /\ | - brg4 brg3 | belt | motor|||pulley What could cause high horizontal readings on the motor bearings? Pulley...
  8. nisqually

    Shaft unbalance caused by oversize key

    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...
  9. nisqually

    Shaft unbalance caused by oversize key

    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.
  10. nisqually

    Shaft unbalance caused by oversize key

    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...
  11. nisqually

    Shaft unbalance caused by oversize key

    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...
  12. nisqually

    Shaft unbalance caused by oversize key

    - - 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...
  13. nisqually

    Shaft unbalance caused by oversize key

    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...
  14. nisqually

    Shaft unbalance caused by oversize key

    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...
  15. nisqually

    Shaft unbalance caused by oversize key

    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...
  16. nisqually

    Bearings sealed or not sealed?

    Sorry I wasn't clearer on my last post. He said if his motor had zerk fittings the bearings inside were NOT sealed bearings. And they needed a thimball of grease per year unless they were running 24/7 then they needed two thimball per year. That was my understanding. I am new at this whole...
  17. nisqually

    Bearings sealed or not sealed?

    I talked to Jim at Baldor. He told me his company does not put grease fittings on motors with sealed bearings. He said his motor bearings need 1 or 2 thimballs of grease per YEAR! He said the grease must be Polyrex EM.
  18. nisqually

    Bearings sealed or not sealed?

    Hi. If I see zerk fittings on a motor then is it safe to assume that the bearings ARE sealed (ungreasable)? My millwrights have told me that motor manufacturers DO put zerk fittings on motors that have sealed bearings. Is this true? If so WHY would manufacturers put zerk fittings on motors with...
  19. nisqually

    Monitoring VFD motor current

    Can anyone give me a few good reasons for monitoring the current on a 5HP motor with VFD? What useful information could be obtained relative to motor condition? We own a Baker Instrument Company Motor Performance Monitor Explorer II Series. Thanks!
Back
Top