Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

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

Search results for query: *

  1. Sofistioelevib

    Vibration spectrum analysis

    More informations should be fine to give you help (machine type, amplitude @1x, waveform type, gear schema and teeth.....) Anyway, the sidebands around frequency around 400Hz (i suppose to be GMF) seems to be not at 1X but lower, 1X and 2X are not visible in this view type but value seems to be...
  2. Sofistioelevib

    firing frequency = numebr cylinder-1 ??? Is this really firing?

    Thank you @GregLocock
  3. Sofistioelevib

    firing frequency = numebr cylinder-1 ??? Is this really firing?

    Update Performed measurement on identical machine. Same spectrum, same time domain, same amplitude this is an indication that 87Hz (7X firing, 3.5X RPM) is not really a faulty component but it is related to a work condition of the machine. Anyway for me still to be unknown phenomenous and...
  4. Sofistioelevib

    firing frequency = numebr cylinder-1 ??? Is this really firing?

    Thank you Greglocock, you are right... information about stroke is important. This is a 4 stroke engine with 16 cylinder and machine was full load. About resonance/bending is exactly what i suppose but i'd like (and i have a chance to do because i can stop machine at request ) to measure in some...
  5. Sofistioelevib

    firing frequency = numebr cylinder-1 ??? Is this really firing?

    Good morning to everyone, some strange spectra today during analisys. DIESEL TCG 2020 V16 (caterpillar) connected directly on MARELLI generator Speed: 1500 RPM I found about 87Hz as exactly 7 times firing frequency (1/2 RPM) till 10 mm/s as below Lot of time i found some problem with...
  6. Sofistioelevib

    Cardan shafts problem

    Thank you electripete for the PDF. Unfortunately i tried to attach photos directly on the message but lot of error appear ... @greglocock This is exactly my idea for lot of reasons. If nothing is cahged for years and only in this period is changed i'm afarid that vendor could be changed...
  7. Sofistioelevib

    Cardan shafts problem

    Hello to everyone, i have really strange case about cardan shaft problems. I attachment you find some photos about one of the cardan shaft failured. This is paper mill company and have big trouble during last year. All motors are DC motors with one AC/DC drive per unit motor. Some indications...
  8. Sofistioelevib

    Best European or world predictive maintenance exibition

    Thank you walt for your suggestion.
  9. Sofistioelevib

    Best European or world predictive maintenance exibition

    I'm creating a new company branch as predicitve maintenance for customers so i need to buy some instrumentation. I've already bought a vibration portable instrument but because i want to provide more services i'm looking for the rest of instrumentation. Often the best opporunity is in exibitions...
  10. Sofistioelevib

    Strange gear tooth pattern

    Thank you to all guys @Strong Really the gear resonance could create these effect? It is a real case you follow up by yourself?
  11. Sofistioelevib

    Strange gear tooth pattern

    Hello Guys, in attachments you found some photo about strange gearbox tooth pattern found. Before the inspection i made some vibration measurement on it discovered this:4 -1XM in axial 13,5 mm/s -2XM in radial 16 mm/s -1XGMF 2mm/s THis machine is forming roll in a papaer machine...
  12. Sofistioelevib

    Strange gearbox tooth pattern

    Hello Guys, in attachments you found some photo about strange gearbox tooth pattern found. Before the inspection i made some vibration measurement on it discovered this:4 -1XM in axial 13,5 mm/s -2XM in radial 16 mm/s -1XGMF 2mm/s THis machine is forming roll in a papaer machine...
  13. Sofistioelevib

    Kurtosis miss indication of impacting

    IRstuff i'm starting to use kurtosis as "new frontier to find bearing problem" as some salesman use to sell his products. Some other speak about technique to find impacting or impulsive signal.... I wanted to try personally and i found it is not really as aspected. Anyway i know some...
  14. Sofistioelevib

    Kurtosis miss indication of impacting

    Hello Guys, i have 2 data acquisition with 2 waveform one with impulse and one without. I made some calculation with my instruments and it is very easy to evaluate impulsiveness of the waveform. Why, instead, Kurtosis seems have missed this impulsiveness of the waveform? Let me know about your...
  15. Sofistioelevib

    Phase of the Frequency Response Function - FRF - Vibration

    Amin, look at higest peak, where you have enough energy to calulate correctly phase. Seems #2 resonance 12 and 37 Hz aprox. In 12Hz it is clear the change phase shift with 90degrees at resonant frequency. In order to well understand if your measurement is correct it is usefull to use choerence...
  16. Sofistioelevib

    Syncronous Magnetic Reluctance motor vibrations

    Just today I learned about the existence of synchronous magnetic reluctance motors. I'm trying to learn about the theory behind focusing on vibration measurements. I think that is as normal motor with some efficiency improvement but i think that in general some different vibrations could came...
  17. Sofistioelevib

    Transient current on 40MVA transformer

    Good morning everyone, i know during braker closing on 132KV system, transformer have a particular behavior. Firstly high current absortion called magentizing inrush current, this current have 10 times steady state current, have distortion because of core saturation. There are considerations...
  18. Sofistioelevib

    Gaussmeter to verify motor field problem

    @electripete yes this is what i want to understand. This technique is already used? It is really usefull as i think? Are commonly use in a investigation techniques?
  19. Sofistioelevib

    Gaussmeter to verify motor field problem

    @strong Exactly what i need, can you share here your experience with? Do you think good help in electric problem? What fault type this technology can reveal? Regard
  20. Sofistioelevib

    Gaussmeter to verify motor field problem

    @electripete i saw an SKF instrumentation (but i'm not certain) moving on rear of the motor to evaluate the magnetic flux of it but i don't remember details

Part and Inventory Search

Back
Top