Join or Manage Your Profile
Posting Boards
Machinery Condition Monitoring and Predictive Maintenance
Posts About Technologies and Techniques for Condition Monitoring
Differentiate shock pulse spectrum and vibration spectrum|
Go
![]() |
New
![]() |
Find
![]() |
Notify
![]() |
Tools
![]() |
Reply
![]() |
|
Dear help
i'm ardi..operator in maintenace...have problem to identify shock pulse spectrum...in this case, i'm still confuse...is it similiar between reading vibration spectrum and shock pulse spectrum.....Spectrum shown high frekuencies 1x,2x,3x, etc..like excessive clereance bearing like in vibration chart.. the position in coupling machine..(refinery machine with cone blade,motor 1 Mw)...Alignment coupling was done..out tolerance in angularity 0.37 mm..and make it correctly to be 0.002 mm..but after..we.alignment coupling the problem still appear... high frekuencies in 1x,2x,3x.etc....is it..right the problem exist in execissive clereance bearing...because..i want to make my boss sure with my explanation.. thank's...i wait ,u r answer..soon sincerely ardi |
|||
|
Ardi,
Please post various plots, give more info on the motor and driven machine. Bearing clearance may not be the only cause. |
||||
|
thank for your respone sir
i attach my sket machine..in below....with spec.data.. We assume that filling gap...in 8.7 mm.. thank's sincerely Ardi sketsDispergerSP2.xls (49 Kb, 50 downloads) |
||||
|
Ardi,
It is difficult to accurately dianosis this problem with the data you have. Some generalizations can be made and assumed, but more specifics are needed. Do you have the capacity to perform the following: 1. Time waveform 2. Phase Analysis Also, although this can not be digitally recorded, it would be of interest to use a strobe for freeze frame analysis to try to visually identify movement on the affected components. If you can gather the above data and post it, I am certain this particular problem can be more accurately diagnosed. ( I did like the Excel sheet for the machine components though) |
||||
|
Thanks to mr david
My condition monitoring instrument isn't shown time waveform and phase analysis, because it's up grade yet...yesterday..in 28/01/2006, we try tighten lock nut bearing one move lock waser..,check nut impeller and alignment coupling by using dial indicator...with result -Parallel missalignment.. H.0.29 mmm to be 0 V. to be 0.08 mm -In angular ..we can't check.because spacer coupling...is too small.... But until now days..the problem still appears.... like the first problem, i tell... in this section i attach waterfall diagram.. waterfallDiagram.xls (20 Kb, 23 downloads) |
||||
|
Ardi,
dimana lokasi anda? anda ada email? |
||||
|
Ardi,
Check the attached chart diagrams. I would suggest getting a vibration spectra using a high resolution (3200 or 6400 lines of resolution) using the velocity mode on the following: 1. Motor - Drive End (output end) Horzontal 2. Motor - Drive End (output end) Vertical 3. Refiner - Driven End (input end) Horizontal 4. Refiner - Driven End (input end) Vertical 5. Refiner - Output End Horizontal 6. Refiner - Output End Vertical What is the RPM of the motor? What is the input RPM of the Refiner Does the Refiner change RPMs from input RPM to where the rotor and stator are? (Is it a straight shaft?) What type of bearings are in the Refiner (deep groove ball, angular contact ball, roller, needle)? See the attached charts, and then apply this to the vibration spectra you get when you perform the above velocity inspections. I think this will be helpful in accurately defining the fault. Please let me know what yo find. SEE ATTACHED CHARTS Descripton_2.tif (250 Kb, 33 downloads) TIF |
||||
|
Ardi, Sorry, I missed the first chart. Also see this one and apply to your spectra.
Description_1.tif (247 Kb, 32 downloads) TIF |
||||
|
Thank for all
Endless, the source of vibration was founded,yesterday....the spectrum with high frekuencies in 1X,2X,3x etc is diseppear..vibration to be normal.. to be 0.8 mm/s.....We realigned coupling once again...and check up tightening bolt impeller..... For Mr david...i had tried use 3200-6400 line resolution...the result is similiar with the first we founded..the differentiate lay on in the range spectrum display...and thank for u r vibration chart..is really help us.. we..r.still monitoring this machine.... |
||||
|
Dear mr david
i'll try to answer y'r question .... -Refiner input is come from rpm motor..it's in line...both of them is just connected by gear coupling... there'sn't reduction in this area...because isn't connected by gearbox... -In this refiner, rotor rpm are similiar with motor rpm.About type of bearing ...mr.D can see in the skets...that' mean...in coupling side...use double tapered roller bearing... thank....y...Cmiw best regrad ardi |
||||
|
| Previous Topic | Next Topic | powered by eve community |
| Please Wait. Your request is being processed... |
|
Join or Manage Your Profile
Posting Boards
Machinery Condition Monitoring and Predictive Maintenance
Posts About Technologies and Techniques for Condition Monitoring
Differentiate shock pulse spectrum and vibration spectrum
