Tagged With "High"

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0.6 pk IPS High Vibration at Large Axial flow pump

Ayaz Ahmed ·
We are facing high vibration an axial Flow Morris Type 54” MPAF pump which is designed for re-circulation of Caustic Liquid. This is an overhung design pump with no bearing support on the Non drive end side and pump is directly installed to elbow of a large pipe. Following are the specifications of equipment Flow: 20,000 m3/ hr. RPM: 242 Driver: 1185rpm, 530 kW Motor Driven through a Gear box and universal coupling Observations:- Highest Vibration at P1H (Pump Inboard Horizontal) of 0.5-0.6...
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45000 dwt Chemical tanker Diesel Generator 4 high vibration on Alternator bearing

chary tatta ·
Greetings team, on 8th July I attended another Chemical tanker and DG no4 alternator bearing Horizontal overall vibration showing 23.4 mm/s in velocity scale. The Marine classification society satisfactory limit is 18 mm/s. Attached the engine and Alternator end vibration spectrum FFT in velocity. All engine details are available in photo sheet. Appreciate your feedback. Kind regards Chary TSR
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6000 v elecric motor high vibration

aziz58 ·
dear all i am facing with high voltage vertical electric motor as follow pole:6 out put:1250kw frequency:50hz speed:993 voltage;6000 v we have high vibration about 5.5 mm/s at 100 HZ de side.but at nde side vibration is 1mm/s. free run test was as same.phase measurement is fluctuated around the body and base.we mount the motor on the same another foundation but vibration was still exist .we decide run the motor on wokeshop on the ground and we put wood block under motor.we tun motor at...
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23 MW Steam Turbine Generator set - High Shaft & Casing Vibration on Generator Front Bearing

vipul@cmc ·
Rated RPM : 3000         Test RPM : 2500 ( No load , Without Excitation ) MW  Rating : 23  ( Russian Make ) Critical Speed : 1590  to 2100 Types of Bearings :  Journal Bearings Problems : (1)High Shaft Vibration on  Generator Front brgs. ( No.:3) ( Trip Value 180  Microns p-p)  machine tripping @  2600-2700 rpm taking while trials  (2) High Casing Vibration on  Generator Front brgs  10  mm/s...
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2x Axial Vibration

ConfMx ·
Hi guys, i,ve a problem with 4Poles Generator 8Mgw in Turbocompressor Solar Mars (Turbine-gearBox-Generator), High Level Vibration Axial NDE 2x (2x1800=3600cpm), 0.26 in/seg(pk). The Last test were with change Load level (decrement from 8Mgw to 0.5 Mgw), Decrease in amplitude is observed due to the change load level: 8Mgw, Level vibration @2x= 0.26 in/seg(pk), the last level (0.5Mgw)= 0.08 in/seg(pk). View Anex. Phases: NDE Axial 1x= In fase (4 axial points, 12,3,6,9) 2x= OutFase 90degres...
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30MW CONDENSING STEAM TURBINE PEDESTAL HIGH VIBRATION

ramonruiz ·
Dear Experienced panel I would like to share one concern about high casing vibration (1x rpm) in horizontal direction of pedestal showed in picture attached. the vibration is 10 mm/sec -rms. the another Steam Turbine pedestal vibration is 1 mm/sec. the question are? 1.- can we allow this part of machine vibrate with this severity? 2.- can the grouting issue to be the cause of this high vibration? 3.- can some resonance frequency be the cause? 4.- can be possible this pedestal has design...
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Boiler feed pump high vibration at discharge pipes than pump and motor

chary tatta ·
Greetings team Please find the attached XL sheet is self explanatory. The boiler feed pump running with high vibrations and the discharge pipe vibration is much higher than pump side. Appreciate your feedback on this pump. Thanks and regards Chary
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Chiller Pump 1-A

Bijoy pradhan ·
Dear all Here with I attached spectrum file of chiller pump-1-A May month pump was running good and vibration was normal but yesterday take vibration vibration was very high so kindly any body suggest me what is the problem on pump .
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Cable requirement for Battery of High Pressure Integrity System Panel

Ratheesh ·
Good day! In our platform, we are installing a battery bank and battery charger for High-Pressure Integrity Protection Panel.Is there any special requirement for the cable entering to battery bank from the battery charger?If yes, please mention the details along with the standard. Thank you for your quick response. Regards, Ratheesh Vidyadharan
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continous high vibration on pump drive and non drive

white walker ·
i just want to clarify my doubt.a pump having 20gE and 27gE at drive and nondrive.velocity was below 1.5mm/s.recently operations were informed they were not getting exact flow.so they removed stainer and cleaned it.they found wastage.after that it was in standby mode.what type of experiments i can do in futurefor same issues.please share ur knowledge.
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Conveyor Gearbox high axial vibration

VANDA BAB ·
Hi every one   iam having problem in Gearbox high axial vibration (High speed I/p shaft)   Conveyor for coal handling in Thermal power station maintaining high axial vibration: (H: 4.0mm/sec    V: ...
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Cooling Tower Fan High Motor Vibration

Andy$ ·
Dears, We have a CT made by 22 cells, separated in 2 Blocks. Last week one of them tripped because of HH vibration on the Motor side (the limit is set to 9mm/s). I checked the spectrum and I found a “strange” frequency that I have never seen on these fans (around 88Hz). The behavior was confirmed by the SKF portable instrument. The speed of the motor is 1485 rpm and fan speed is 106 rpm (6blades). I suspected some looseness so I suggested to make an inspection, looking for some loose bolts...
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Cooling Tower Gearbox High Vibration

Fahad Qureshi ·
Hi! We have five induced draft cooling fans installed at our site. Recently we experienced high vibration on one of our fan gearbox having accelerometer installed in horizontal direction to gearbox casing. The max vibration was around 17 mm/sec and spectrum revealed GMFs with modulation where 2 x GMFs dominated for first set gears which are spiral bevel gears. Any idea what could be the probable issue?? Is it due to misaligned gears?? If yes then what factors could contribute to this issue?
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Re: High Vibration

electricpete ·
If some kind of rotor asymmetry is causing vibration oscillation of at pole pass frequency during solo run, vibration will vary very very very slowly (pole pass period might be 30 minutes). Rotor asymmetry could include a static bow or a dynamic bow (operating near flexible rotor resonance) or excess bearing clearance or (less likely) rotor bar problem. by the way, we don't know anything about your machine (horizontal/vertical, bearing type, which direction was 1x measured).
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Re: 6000 v elecric motor high vibration

Abdul Hakkeem ·
2x LF ??? pls post FFT... Did you check any side bands around there..
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Re: seal air fan (Radial Fan) Axial Vibration

Walt Strong ·
" that 7.6 orders matching with bearing outer race but after checking the bearing outer races are normal" You have outer race fault frequency with 1xSS sidebands (modulation), so it sure looks like an outer race fault! How did you or someone actually "check the outer race"? Most bearings require destructive disassembly (cut apart) to actually see the full bearing race surface. Don't get lost in a pile of data! Walt
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Re: seal air fan (Radial Fan) Axial Vibration

Shurafa ·
Were these spectra collected before after the "bearing checks"? Did you replace the bearings or you reinstalled them? It looks there is a bearing defect. Regards-Ali M. Al-Shurafa
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Re: seal air fan (Radial Fan) Axial Vibration

y@sh ·
Above spectrums are After checking the bearings and alignment and we find inner clearances but there is no outer race defect physically
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Re: seal air fan (Radial Fan) Axial Vibration

y@sh ·
We check the bearing clearances with feeler gauge inner and outer
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Re: seal air fan (Radial Fan) Axial Vibration

y@sh ·
We disassemble the both de and nde bearing and checked physically but there is no Outer race defect
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Re: seal air fan (Radial Fan) Axial Vibration

y@sh ·
bearing images
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Re: seal air fan (Radial Fan) Axial Vibration

y@sh ·
BEFORE ALIGNMENT
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Re: 6000 v elecric motor high vibration

aziz58 ·
hi abdul this is not 2x LF. because we turn off the motor but 100 HZ don t disappear rapidly . we dont have side band around there. best regards
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Re: 6000 v elecric motor high vibration

Abdul Hakkeem ·
Hi post the FFT and vibration reading... Did you check coupling???
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Re: 6000 v elecric motor high vibration

aziz58 ·
I try post fft. all test don free run and uncoupled .
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Re: 6000 v elecric motor high vibration

Shurafa ·
Did you notice any noise? Are you sure the data collected have a good resolution to separate possible nearby frequencies? Regards- Ali M. Al-Shurafa
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Re: 6000 v elecric motor high vibration

Becar ·
You should make some shutdown waterfall. ˝this is not 2x LF. because we turn off the motor but 100 HZ don t disappear rapidly ˝ Word rapidly is not enough for a good analysis.
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Re: 6000 v elecric motor high vibration

aziz58 ·
thanks for all we dont have side band. my question is why 100HZ freq disappear when we start motor at600 rpm on the ground at work shop. what was happened for that. i think it is related to soft foot or distortion of motor frame. do u agree with me?
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Re: 6000 v elecric motor high vibration

Becar ·
That is because you reduced rpm. 600rpm/993rpm = X / 100Hz. So at 600rpm you should see disturbance at app. 60Hz. The amplitude should not be so dominant because of reduced speed. Normaly you should better see this electric source disturbances in the envelope spectrum.
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Re: 6000 v elecric motor high vibration

aziz58 ·
thanks becar after reduce rpm we dont have 60HZ at de side. envelope was normal with out any specific frequency. just at ndes side we have 1x peak at fft.
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Re: seal air fan (Radial Fan) Axial Vibration

electricpete ·
[quote] inner race clearances was 0.3 mm.[/quote] Can you explain more about this measurement? I hope it is not between bearing and shaft (that should not be clearance) What style bearing is it?
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Re: seal air fan (Radial Fan) Axial Vibration

montaser ·
I advice you to make mark using (correction pen) between the bearing outer race and lower part of housing and another mark between bearing inner race and shaft, and keep the fan running for some hours, then stop and inspect the marks position for the possibility of bearing rotation inside the housing.
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Re: seal air fan (Radial Fan) Axial Vibration

y@sh ·
Tnq for reply its not b/w shaft and bearing ,clearances are b/w balls and bearing inner ring.
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Re: seal air fan (Radial Fan) Axial Vibration

y@sh ·
thank you sir but it is a heavy equipment . so,it's impossible to open the machine at present conditions.
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Re: seal air fan (Radial Fan) Axial Vibration

Jim1 ·
Oil filled housing? Did you sample the oil? What caused the satin finish on the rollers and inner raceway?
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Re: seal air fan (Radial Fan) Axial Vibration

Walt Strong ·
Y@SH, I looked at your three photos. None of the photos show the surface of the outer race/ring that is in the contact path of the rollers. The bearing would have to be destructively taken apart to do so. Therefore your limited inspection does not prove or disprove an outer race defect. The only way to do that would be to remove the grease and cut the bearing rings apart. You can save that activity for a later date when you change the bearing. If you actually put in new bearing when those...
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Re: 6000 v elecric motor high vibration

Ron Brook ·
Put the motor back on it's base, uncoupled and loosen one foot while up at speed. Tighten and do next foot and so on until you find foot that drops the vibration. That would confirm your theory of a twisted frame due to soft foot. Ron Brook
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Re: 6000 v elecric motor high vibration

Dan Timberlake ·
pictures please. Vibration of a vertical motor on a pump is usually higher than a horizontal motor. Structural weakness and even resonance are frequently the problem. 1X, blade pass, or any other excuse is all the structure needs to throw a tantrum.
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Re: High Vibration due to flow turbulence

Alvaro Loayza ·
Hello, We also experienced a similar case, it's very usual to see this condition on recirculation mode. There is a water pump system where we have 4 pumps working to boost water to our cupper concentrator plant. In minimum flow requeriment one of them was supposed to recirculate water to the tank and had flow restriction on pipe because of its diameter and valve flow restriction itself. We recommend to recirculate for short periods and the valve fully opened because this valve was suffering...
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Re: High Vibration due to flow turbulence

electricpete ·
Yup. Operating at too low flow creates excess internal recirculation and can result in recirculation cavitation (not your normal cavitation due to low npsh) Increase in broadband and in blade pass are classic symptoms Prefer nto avoid that condition too long., There are certainly design changes that could be made to make a pump more tolerant of this condition. Ordinarily that would only be pursued after pump inspection showed evidence of a particular damage mechanism from the recirculation.
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Re: High 2660 CPM vibration at variable speed 4 pole electric motor

Bill Keeter ·
Does this occur in one motor only, or in all six?
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Re: High 2660 CPM vibration at variable speed 4 pole electric motor

Ander ·
Proceed a shutdown test, you will know if the vibration comes from eletric problem.
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Re: High 2660 CPM vibration at variable speed 4 pole electric motor

Rotate ·
I have seen and corrected vibration problems coming from the VFD controls. Change the VFD control speed and see if it goes away. If it goes away, look into the controller.
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Re: High 2660 CPM vibration at variable speed 4 pole electric motor

Callum S ·
if the vibration frequency of interest is present on all 6 machines it may be from another source completely. 2660 / 3 = 886 rpm . Possible vane pass from a nearby pump or mixer etc rotating at 886 rpm?
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Re: High 2660 CPM vibration at variable speed 4 pole electric motor

Dave Reynolds ·
What does the vibration do when you run the motor slower or faster than 87-97%? What type of bearings are in the motor? 1) Data you posted shows a high 2x TS peak, the ratio of vibration from 1x to 2x is over 4:1, this is not normal, can indicate a resonance issue. 2) At the base of the 2x TX peak, notice how it has a small "haystack" of energy, this is can be an indication of a natural frequency, done any bump tests, startup/coastdown tests? 3) With the motor running at trouble some speeds,...
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Re: continous high vibration on pump drive and non drive

y@sh ·
Go for CFD , spectrum shows exact flow peaks if its a flow issue
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Re: Examples Of High frequency vibrations?

Dave Reynolds ·
Your request is not something that most people are involved with....most machinery vibrations occur way below 6khz, the range you are requesting belongs in the "ultrasonic" range, typically ultrasonic equipment measures this frequency range. http://www.uesystems.com/resources https://www.maintenance.org/top...ed-us-training-class Dave
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Re: Examples Of High frequency vibrations?

Vibration_guy ·
But sir, If no vibration generates with such high frequency then why the Instrument Manufactures gives instruments with frequency ranges upto 40 khz, 80 khz(for vibration). Are they fooling US?.
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Re: Examples Of High frequency vibrations?

Dave Reynolds ·
Ultrasonic evaluation in the 20-100khz range, is used for air leak surveys, steam traps, lubrication, bearings etc. Your statement "instrument manufacturer" encompasses millions of pieces of test equipment. Some people maybe using an instrument/data collector to identify frequencies in this range, but there would be a very small number of people doing this. Example, jet engine turning 26,000 rpm with 200 individual blades on one rotor, 26kX200/60=86,666hz/86khz or 5,200,000 cpm No one is...
 
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