Tagged With "High"
Topic
6000 v elecric motor high vibration
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...
Topic
0.6 pk IPS High Vibration at Large Axial flow pump
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...
Topic
23 MW Steam Turbine Generator set - High Shaft & Casing Vibration on Generator Front Bearing
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...
Topic
Boiler feed pump high vibration at discharge pipes than pump and motor
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
Topic
Conveyor Gearbox high axial vibration
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: ...
Topic
Cooling Tower Fan High Motor Vibration
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...
Topic
GT SGT600 PT bearings 3 & 4 High Vibration
Dears, We have experienced dramatic change of vibration over GT24 "SGT600" where bearing 3, 4. We have stopped the unit and start it again and vibration trend still high, specially bearing 3. We also carried out NDT test on PT coupling shaft but found no trails for cracks! The high vibration parts are shown in following schematic: the attached files contains all the required data. any suggestions about this?? it will be appreciated
Topic
High Vibration due to flow turbulence
When Turbine driven boiler feed water Booster pump was running on recirculation(minimum flow condition) the vibration readings at pump DE and NDE vertical were very high but when pump started to give flow to turbine driven pump(Main Pump) its readings drastically dropped. I saw the spectrum the peak is exactly at the vane pass frequency. Therefore it is suspected that this is purely due to flow turbulence when pump is running in minimum flow condition. (See Spectrum in attachment) Any one...
Topic
high vibration in compressor
dear all we are facing high vibration in a screw compressor over a period of time which is situated in 660MW thermal power plant.the vibration in compressor is 22mm/s RMS on 25 of jan. then we cleared the air fillter & oil filter also but vibration is still high.After these action the vibration is now 19mm/s RMS. i attached the various spectrum & trend also. No other useful information i have.
Topic
high vibration in motor side
sir we are facing high vibration at motor side .its a 113 kw motor.sir give ur suggestions on urgent basis
Topic
high vibration in pump
Dear all would you please tell me what is the main reason of increasing vibration only in radical direction..
Topic
High vibration on 356 HP Motor- 742 RPM Vertical Pump- Sea Water Duty
Hi , We are facing High Vibration on 356 HP Motor- 742 RPM Vertical Pump- Sea Water Duty Kindly find the attached sheet with all details - Kindly give what could be the possible reasons for high Vibrations. Regards,
Topic
High Vibration peak at 110Hz
I am getting a high vibration peak at 110 Hz and it is there in the pump. The pump speed is 68Hz. This is a horizontal pump with a gear box between the motor and pump. Kindly advise what is the cause.
Topic
High gear pump vibration
Hello to everybody, We have 6 ball mills in a cupper concentrator plant. These mills suport over two pad bearings (fixed and floating) that are lubricated with high pressure oil. Every mill has a lubrication room with two oil modules, one for each pad and works with high pressure Rickemeir gear pumps. Our problem is that almost all of these high pressure pumps have a very high level of vibration in some cases they reach 54 mm/s at GMF of pump gears. Do you suspect which could be the source...
Topic
High horizontal vibration on gearbox
i have a dynamic separator fan in cement mill area. a motor, gearbox and a fan. gearbox has 2 shafts. i m facing 1x horizontal high vibration 8.5mm/sec and 8mm/sec on shaft 2 DE and NDE side. All other points showing less than 1mm/sec including Motor. also find attachment
Topic
High pressure gear pump vibration problem solved
Hello everybody, A few days ago i posted a topic about a problem we had in our high pressure gear pumps. Here is the original post: http://www.maintenance.org/topic/high-gear-pump-vibration I want to share with you the way that we solved this high vibration problem. After checking pad oil piping at discharge in both fixed and floating mill bearings, we noticed that high vibration was still significant and even higher on hosepipes that were connected in every pump discharge connection. So I...
Topic
High Rms @ x1 Axial
Guys/Girls if i could ask for some advise that would be a great help. I am pretty new to vibration analysis and i have come across what i think is a high reading taken from the axial position on the drive end bearing of a Kato 1540Kw Generator. From...
Topic
High turbo expander load bearing temperature
Dear all, I just finished overhauling the Atlas Copco Rotoflow turbo expander and now it has an issue that needs troubleshooting. I would deeply appreciate if someone can help me to troubleshoot this problem The problem is as follows: The load (compressor side) bearing temp is 73 C @ 23,730 RPM and it will increase when RPM increases. If the RPM reaches around 25 000, the load bearing temp will go up to 78 C which is over the alarm limit_75 C. When I did the overhaul, all clearances...
Topic
High Vibration
Hello, We installed a rebuilt electric motor and performed a solo run test after it had found it's mag center. We had a report of .1 IPS is threshold of acceptable this measures .235 IPS of 1 x unacceptable. The bolting was is tight to the motor and foundation to grout, We then pulled together the group went out and retested our reading were acceptable good condition. Could rotor sag caused the first bad reading? Unit has proximity probes we will tie equipment into them for further...
Topic
high absolute vibration in critical speed in a gas turbine
Hello all dears, A gas turbine having few problems has been shut down for about 4 years in an industrial plant. Now, after maintenance of the gas turbine and replacing of the turbine shaft and running it, the absolute vibration of journal...
Topic
High axial vibration at 18x in a flowserve pump electric motor.
Hello, I have 10 identical flowserve water pumps. They are driven by a 1620 HP ABB electric motor. In 9 of these pumps I have very low amplitudes of vibration in every direction at electric motor. (0.3 -- 0.5 mm/s) I supposed this is because of system stifness But in one of them, specifically in axial direction I have very high levels of vibration (7.1 mm/s at exactly 18x) This shafts turns at 1180 RPM. So frequency is aproximately 21200 CPM. This vibration is higher (7.1 mm/s) as close to...
Topic
High Electrical/ RBPF vibration
Looking for some help. We have a 300HP Siemens motor 4160V that we recently rewind from a 2 speed (900/600 rpm) to a single (600 rpm) speed. I'm getting ODE axial 0.475 in/s at 7200, ODE Horizontal I'm seeing 1xRBPF 0.218in/s with sidebands of 2xFL, ODE Vertical 0.529 at 7200 with multiply following and on the DE Horizontal i have 0.063in/s at 7200 with sidebands of running speed. i have checked with our PdMA tester and came back with no issues. Vibration spectrums
Topic
High Frequency Haystack - is this lack of lubrication
Hi I collected data from a 2 week old vertical mixer which is noisy and sounds like a dry bearing. The motor uses sealed bearings so they cannot be lubricated. The high frequency vibration data shows a haystack between 2KHz and 2.5Khz primarily...
Topic
NDE generator of ge frame 6 high 1x vibration
dear all i face to high vibration near alarm limit at 1x at NDE side of generator that coupled to gear box of ge gas turbine frame 6 driver. DE side of generator is ok. my question is about the difference phase between x and y sensor located at NDE IS 170 dgree.a magnitude x is near two times y direction. can i say we have unbalance defect .orbit shape is elliptical . can you show me standard or text book that mention difference phase at one bearing must be 90 degree when we...
Topic
seal air fan (Radial Fan) Axial Vibration
hello guys, help me out from this problem the radial fan getting 7.6 orders and its harmonics . high vibration on axial side 17 mm/sec .fan have 11 no.of vanes and that 7.6 orders matching with bearing outer race but after checking the bearing outer races are normal and inner race clearances was 0.3 mm. i am unable to identify the this problem please,help me guys
Reply
Re: High Rms @ x1 Axial
Do you have any comparison with previous values or other simular equipment? Diesel engines can generate high vibration without anything wrong. If there is an increase in axial vibration, especially 1X and, as i see in your spectrum, harmonics of it, you should check the alignment and if the coupling rubber got hard by aging.
Reply
Re: High Rms @ x1 Axial
Hi Edwin firstly thanks for your response. I have done 5 other generators which are the same. Same mount arrangement same load etc maybe 5-6 rpm difference. I am getting Rms values ranging from 5.223 being the lowest to 6.612 the highest which all seem to be consistent. It just got alarm bells ringing in my head with the high reading of 8.41on the generator which is basically an emergency back up generator with the least running hours on. I have initially advised alignment checks to be...
Reply
Re: High Rms @ x1 Axial
I'm not sure about the Vulkan coupling but on a competitor type of coupling in a diesel driven test stand application there was some recommended maintenance in the form of application of a rubber lubricant. We used to do this every six months. It was a relatively simple task that involved unbolting a plate and spraying rubber lubricant on the rubber blocks. It might be worth checking if the Vulkan has a similar maintenance procedure.
Reply
Re: High Rms @ x1 Axial
P Dunk, You are suggesting the two best causes for an elevated axial on a Kato gen set. Usually the lowest of the vibration readings. Ron Brook
Reply
Re: High Rms @ x1 Axial
Dear P Dunk, you have to look on your trend,if it's increase you have to be worry,we have for 3512 gen diesel pump,rms is on axial is 14mm/s but the trend at the begining is steady,just contunie to monitor it
Reply
Re: High Rms @ x1 Axial
Originally Posted by P.Dunk: From what i can make out i am getting my main peak at x 1 running speed and there after. I will upload the images. The generator is driven by a caterpillar 3516 diesel engine. Engine and generator are spring mounted. Generator speed is1202 Rpm. Coupling is a vulkan solid rubber spider type. I noted with interest that you state that the predominant vibration is in an axial direction referred to the input shaft. Comments (including my own) so far have been about...
Reply
Re: high absolute vibration in critical speed in a gas turbine
It is likely the rubbing when high vibration happen which show that it is dominant in 0.5X, the 2x in normal situation is due to misalignment but it is also by some other effects. how about the rotor? it is from OEM? how about a residual unbalance? The bent shaft after long time remaining in horizontal storage is able to be a case in this situation. But where the transducer probe located? how about the diagram of machine arrangement? type of bearings? how about clearance? type of...
Reply
Re: high absolute vibration in critical speed in a gas turbine
Originally Posted by m-afshar: 1-What kind of problem may the machine have according to the FFT graphs? 2-Is it possible the bend-shaft has occurred? 3-Is there more suitable condition monitoring system to measure relative vibration of the shaft? Thanks M. farhadi Afshar 1. We would need the "FFT Graphs" to better answer this question. 2. Yes, most likely the rotor was stored horizontally, taking on a bow. Did you have the rotor rebalanced prior to installation, or did you take it out of...
Reply
Re: 0.6 pk IPS High Vibration at Large Axial flow pump
Can you provide a multiple point waterfall, include HVA directions, at each bearing location on the gearbox and pump, if you can get the motor in there also that would help. 18 points maximum allowed in AMS software Resolution of your data is not sufficient enough to determine what frequencies are present, can you take a set of velocity readings on this machine with a 6000 cpm fmax, 1600 LOR, 4 avgs, 50% overlap. Also collect peakvue with 60,000 fmax, 1600 LOR, 500hz and 1000hz filters, 1...
Reply
Re: high vibration in motor side
sir after replacing the old motor with a new one same problm is occur. vibration still high on drive side
Reply
Re: high vibration in motor side
alingment is checked and it is under 0.02mm both angular and parallel
Reply
Re: high vibration in motor side
Check impeller or it may be bearing housing loosnes...Same specter I saw when I had to disassemble whole pump.
Reply
Re: high vibration in motor side
pump bearing is checked cage of the nde side bearing found damage.we replaced the both bearing. vibration is down at motor nde side but still high at de with same spectrum.no change in spectrum
Reply
Re: high vibration in motor side
Hi Vishal! what type of coupling installed in this pump, if it is disk pack.. Kindly check disk element, coupling bolts, and holes. I have experienced these spectra and found out to be defective coupling.
Reply
Re: high vibration in motor side
dear morse ! we check coupling and found the flange of coupling minor damage.i send the pic . tell us would it is the main cause of high vibration
Reply
Re: High gear pump vibration
It sounds like these are new (recently commissioned) equipment but with very high vibration. Despite the cause, I would recommend to involve the supplier/vendor/manufacturer/contractor responsible based on the contractual details. On the analysis side, it might be useful to take high resolution and high frequency vibration. High resolution plots may exhibit important components near the GMF. High frequency plots may exhibit orders or other higher frequencies this HTML class. Value is...
Reply
Re: High gear pump vibration
Shurafa, Thank you very much for your reply. Well, we have already contacted Polysius for further information about these pumps problem. We are waiting for their response. These mills have been working for 6 months and all our measurements have been trended with a 1000 hz 6400 lor even with pump vibration points. So if my electric motor turns at 1780 RPM and the gear pump has 11 teeth, do you suggest a 300000 CPM fmax with high resolution ? About time behavior there isn't a significant...
Reply
Re: 0.6 pk IPS High Vibration at Large Axial flow pump
First of all sorry for the late response; I could only make to the pump yesterday. Please find below the required information 1. I have attached multiple point waterfall for all the points except Peakvue plots. 2. I have attached different plot for the Pump with better resolution as required. 3. Two readings of Peakvue also attached. 4. Pump was completely replaced with an overhauled one, elbow is part of pipe and we didn’t replaced it. 5. I will take bump test reading in the next shutdown...
Reply
Re: 0.6 pk IPS High Vibration at Large Axial flow pump
I don't know why I can't attach anything in my reply and how to delete or edit my response
Reply
Re: 0.6 pk IPS High Vibration at Large Axial flow pump
When you reply, in the bottom right corner it shows "add attachment, see below now
Reply
Re: 0.6 pk IPS High Vibration at Large Axial flow pump
Response definitely looks like resonant energy. Have you checked all of the supporting piping connections and supports to ensure they ? I don't suspect a flow condition because the axial direction and vertical directions look OK. Check any supports that would affect horizontal stiffness. Ron Brook
Reply
Re: 0.6 pk IPS High Vibration at Large Axial flow pump
In that case the CSI Function of Bump Test "Equipment Running" will be on any help? Actually as discussed earlier and can be seen in the above attachment of Pump general drawing, there is no separate support for the pump, it's just directly bolted to the flange on the elbow. However the suction 86" line which is coming from a Caustic crystallizer must have some supports (which am not very aware of). However as mentioned earlier this problem started after replacing the complete pump in Plant...
