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Vibration Acceptable Limits at Vertical Motor

  • 1.  Vibration Acceptable Limits at Vertical Motor

    Posted 03-11-2024 06:52

    Hi every one , 

    If anyone can support me with a vertical induction motor, how can we find the acceptable vibration limit , I know that for this type of machine, the vibration limits depend on the height of the motor and the speed, but I don't know from which source we can find this chart , API or ISO. please if anyone knows this information, share it with us. Thanks in advance 



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    ahmad alfakeer
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  • 2.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 03-27-2024 08:21

    ANSI/HI Standard 9.6.4 is a good source of reference for acceptable vibration limits for many styles of pumps. Vibration limits are based on horsepower and pumps actual operating point on pump curve, not height or speed.



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    Dave Reynolds
    www.midlandsrc.com
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  • 3.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 03-28-2024 13:35

    ANSI/HI 9.6.4 is really more appropriate for pumps.  There is only a "recommended" limit for vibration at the top of a vertical motor.  Use ISO 10816-3 for motors, because it allows for base flexibility.  Set your acceptance limits to the Zone B/C boundary.



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    Lyn Greenhill
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  • 4.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 03-28-2024 16:52

    Perhaps the overall vibration level is much less important than the source of the vibration. The overall level is like a sum of all the individual vibrations that when added together give the overall amount. The specific frequencies of each vibration relate to the causes. Their amplitudes reflect the severity of each condition. It is common for a low amplitude vibration, one that has either very little or almost no effect on the total, can be a cause for impending catastrophic failure.

     

    Please don't get sidetracked by 'vibration severity levels' even if they are produced by 'reputable' sources. Seek the advice of a qualified and certified vibration analyst, one who can tell you all the specific conditions present and if any of them are severe enough to warrant action.



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    Jim Carrel
    COO
    Forum Reliability, Inc.
    Fate TX
    2068928074
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  • 5.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 03-28-2024 06:44

    check ISO 20816-3



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    Ayman Gamal
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  • 6.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 04-04-2024 10:35
    Edited by Ali Al-Shurafa 04-04-2024 10:36

    You might be looking for something like this.

    Regards- Ali M. Al-Shurafa



  • 7.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 04-04-2024 18:42

    Nice figure, but not supported by any standards, so couldn't be used for acceptance.



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    Lyn Greenhill
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  • 8.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 04-06-2024 02:37

    Dear Lyn, 

    I guess what you meant was that all limits must be mentioned in international standards otherwise, they couldn't be used for acceptance.

    May I understand why?

    Regards- Ali M. Al-Shurafa



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    Regards- Ali M Shurafa
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  • 9.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 04-06-2024 12:46

    Ali,

    Your chart makes perfect sense.  However, nearly all of the specs for vertical motor acceptance vibration we (DynaTech) deal with reference either ANSI/HI 9.6.4 or ISO 10816-3.  As such, while your chart certainly captures the characteristics of vertical motor vibration, it couldn't be used for acceptance.  For low speed (< 600 rpm) pumps, the HI standard does have a vertical height adjustment, and we always assume that the modifier also applies to the "recommended" motor vibration limits, although it doesn't explicitly state that.

    What I would suggest is that you submit your chart to the Hydraulic Institute, since they are doing an update to the vibration limits for 9.6.4 and are looking for input, preferably from test data.  I am planning on compiling our 24 years of test data and submitting it, primarily based on power, but I could sort on height with the motors as well.



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    Lyn Greenhill
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  • 10.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 04-07-2024 07:26
    Edited by John Winterton 04-07-2024 07:28

    That symbol after the 12 means feet.   12'

    The IEEE standard symbol for a foot is "ft". In some cases, the foot is denoted by a prime, often approximated by an apostrophe, and the inch by a double prime; for example, 2 feet 4 inches is sometimes denoted as 2′ 4″.



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    John from PA
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  • 11.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 28 days ago

    Thank you @ for your explanation, 



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    ahmad alfakeer
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  • 12.  RE: Vibration Acceptable Limits at Vertical Motor

    Posted 04-07-2024 05:27

    Thanks, @Ali M. Al-Shurafa, for your reply. Do you have any references for the attached chart? Because this chart doesn't make sense for the big induction motor and this chart for the very small motor, from the chart, the highest H = 12 INCH is equal to 30 cm. For my case, I have a vertical motor with a height of 1.20 m. How can I use this chart?!!! 



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    ahmad alfakeer
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