Tagged With "data"

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CMMS as viewed by Reliability Engineers

planschd2 ·
I wish reliability professionals would recognize that we too are important . There are many experts in the field of condition monitoring, defect elimination, root cause analysis, RCM analysis, etc. and they believe strongly in their approach. The CMMS is a valuable database containing asset registers, asset failure history, asset criticality, spare part data, warranty information, asset age/installation-date/replacement cost, asset classification data, job plan libraries, PM/PdM...
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data requirement for cmms

aziz58 ·
hi all dear   if i want to  implement cmms , what are steps for this approach? do you have practical standard or procedure ?   best regard
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High 2x between 2800 to 3000 rpm on Gen DE

Nagaraja ·
Hi I am working on a 12 MW TG set vibration problem The history is generator was working fine with vibs in permissible limits. Due to earth fault there was a prob in stator. Stator was replaced. Both generator bearings were replaced. Now Gen DE...
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How important are asset taxonomy and coding?

Reliability ·
How can you zero in on maintenance improvements without failure data?  
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ODS - wire model move, problem visualization

czJKr ·
I discovered that there are multiple approaches for creating an ODS moving "wire" model. ODS data for model can be collected easy as amplitude and phase angle on problematic frequency (1x). Second approach return few spectrums datas (FFT, Coherence,...
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Orbital Data Collection (Training)

Pump Guy ·
I have two questions: 1. I would like to know name of places that offer training for orbital data collection and 2. How to calibrate proximity probes for different shaft materials? Thanks in advance for your help!
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Rollers turning sideways in agitator bearing

tcvib ·
We have had a failure in an agitator bearing that the area reliability engineer said the bearing rollers were turned sideways. The question has been asked if there is a way to pick this fault up? Thinking about this, if the rotating element gets turned in the bearing what type of signature should we expect. Looking at the data I see no indication of a severe condition in the agitator bearing.
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Smart Vibration Analysis

Reliability ·
From a article posted at Reliabilityweb.com Since leading indicators at inception are not yet typical “wall chart” fault conditions, finding them as they happen requires a really close look at every spectra and a comparison to historical signatures to distinguish them from normal, transient conditions related to load, temperature, process rates, accelerometer data, etc... Read the full article
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Sufficiency of Historical Time to Failure Data

lewiseyo ·
I am an M.Eng student and doing a work on determining the Reliability of a centrifugal pump. I have been able to get the Time to failure historical data of the centrifugal for 8yrs, but I want to know if this data is okay to determine its reliability using weibull and also if I can use same data to determine the MTBF of this pump.
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Re: High 2x between 2800 to 3000 rpm on Gen DE

John from PA ·
Is this machine equipped with proximity probes, and if so can you collect data appropriate to generate bode, polar and cascade plots? [Preferably compensated]
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Re: High 2x between 2800 to 3000 rpm on Gen DE

Walt Strong ·
I suggest impact (bump) test on Gen DE and NDE bearing housing in axial direction and also on Gen housing end plate. I assume that both shaft alignment and possibly natural frequency was disturbed during the repairs. Walt
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Re: High 2x between 2800 to 3000 rpm on Gen DE

Nagaraja ·
I do not have instruments to generate bode and polar plots...I am sorry....I took the phase data...already posted...it shows common phase between Gen DE and GB DE....bump test done on coupling....I got 135 Hz....tom we are opening the bearings for inspection.....will do the bump test on that also.....only thing is what changes in dynamic behaviour might be happening for the 2x along Gen DE axial to increase in the last 200 rpm before reaching rated speed...of 3000 rpm....???
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Re: High 2x between 2800 to 3000 rpm on Gen DE

Nagaraja ·
Gen DE bearing found in damaged condition
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Re: High 2x between 2800 to 3000 rpm on Gen DE

Nagaraja ·
Dear Members I have a question....in which direction do 2x line freq showup on Generator.......DE, NDE or both... HVA....???? In this case 2x is appearing on Gen DE axisl once generator speed crosses 2800 rpm and shows 8 mm/sec at 3000 rpm It was found that Gen DE bearing top half was damaged that too only on one side left hand side where as no damage was found on right hand side and also bottom half bearing. In real time I can see 2x freq component was hunting....from 6-9 mm/sec. Is 2x...
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Re: data requirement for cmms

candy ·
Not sure if there is a standard but CMMS is in fact maintenance management. So I thought one got to know the original substance before going computerised. Have you bought the CMMS software? Is implementataion of CMMS a collective decision by the whole maintenance dpet?
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Re: High 2x between 2800 to 3000 rpm on Gen DE

William_C._Foiles ·
A planet earth fault can result in serious torsional oscillations in the shaft. Shaft asymmetry can cause 2X vibration. A generator running at 3000 (?) has some natural asymmetry. Torsional oscillations can result in a shaft crack, which usually shows up as a shaft asymmetry (for bending). It might be prudent to setup a monitoring plan for this.
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Re: High 2x between 2800 to 3000 rpm on Gen DE

oscarsaenz ·
Originally Posted by Nagaraja: Hi I am working on a 12 MW TG set vibration problem The history is generator was working fine with vibs in permissible limits. Due to earth fault there was a prob in stator. Stator was replaced. Both generator bearings were replaced. Now Gen DE axial vibs are high. Turbine speed 7066 rpm and Gen speed 3000 rpm. Ita a 2 pole machine. My observation was till 2800 rpm the Gen DE axial vibs are normal (1.5 mm/sec rms) with slight 1x ampl and very low 2x ampl. After...
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Re: High 2x between 2800 to 3000 rpm on Gen DE

oscarsaenz ·
Originally Posted by oscarsaenz: Originally Posted by Nagaraja: good day engineer your case is very interesting because it has shared behaviors of different faults. I think the vibration at 1500 rpm (0.5 X). possibly induced by the friction which to change the rigidity of the system, move the natural frequency of the system. besides possible rigidity of coupling.
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Re: High 2x between 2800 to 3000 rpm on Gen DE

Nagaraja ·
Hi generator was balanced after bearing change....now the set is running with both casing and shaft vibs in the permissible limits thanks for all your valuable inputs.
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Re: Sufficiency of Historical Time to Failure Data

Joyce Brook ·
Reliability of a unit is not tied to its run time to failure alone. You also have to factor in environmental conditions, usage rate, maintenance policy, operator error etc etc. The MTBF is the run time to failure, based on the probability that the factors described remain constant and taking into account the age of the unit against its expected life. This means that a relatively new unit will not be expected to fail as frequently as one nearer to the end of its expected life. As I am not a...
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Re: Rollers turning sideways in agitator bearing

davidWHITMAN ·
One thing I'd watch for is FTF and FTF sidebands especially in a high frequency shot. If the cage wears the rollers can turn and that takes all the clearance out of the bearing. Can be more difficult to catch in a low speed shaft. Using the Time Domain can be useful. Especially if you have Auto Correlation available. Lack of lubricant can cause cage wear.
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Re: Rollers turning sideways in agitator bearing

Ralph Stewart ·
Quote: "Looking at the data I see no indication of a severe condition in the agitator bearing." Is this the last data before working on the agitator? How long before the shutdown was this data taken? Is the Fmax of 3000 CPM, the longest you take? Do you take some kind of enveloped data? What is the trend value above the 3000 CPM Fmax length in Gs? The data appears to have quite a bit of high frequency energy that does not appear to stop at 3000 CPM, IMO. Slow speed rotors usually, as a rule,...
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Re: Rollers turning sideways in agitator bearing

davidWHITMAN ·
The TWF is showing Pk to Pk at about .1 in/sec and this is not showing in the FFT (which shows Pk at .0225 in/sec). I might conclude that this is random impacting since the FFT only shows peaks that repeat. Compare past TWF to this. I like to take a high resolution shot at 300,000 CPM (5K Hz) and watch the FFT for side banding and raised floor and impacting in the TWF.
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Re: Rollers turning sideways in agitator bearing

Dan Timberlake ·
Please post pictures/drawings of the installation, and where the vibration is being measured. And provide historical info. As others said, the sequence was likely lubrication issues causing progressive cage wear. It probably did not happen in a few days. And measuring vibration using other parameters would have "caught" it. Are the agitators mounted with the shaft vertical? Or, are they "side entry?" http://www.vismec.co.th/images...8548223/P9250015.jpg If so, have there been problems with...
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Re: Smart Vibration Analysis

candy ·
Is this smart vib analaysis include in the vibration certification courses?
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Re: Smart Vibration Analysis

RRS_Dave ·
Narrow band alarms statistically set.
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Re: Orbital Data Collection (Training)

Mile High_PumpFE ·
I asked the guys at Technical Associates about this..... they cover a bunch of it in their level 4 class, and there is a rotor dynamics class that Texas A&M gives once a year in Houston that is supposed to cover quite a bit. I have looked for this also, as I have yet to find a class just dedicated to this topic. I have one of my engineers in the Texas class now.... will let you know how this goes.
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Re: Orbital Data Collection (Training)

Pump Guy ·
Someone in TX takes a class once a year dedicated to orbital analysis.
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Re: Orbital Data Collection (Training)

John from PA ·
I assume you have reviewed the "Orbit Tutorial" located at https://www.maintenance.org/topic/orbit-tutorial . Beyond that I'm not certain you will find dedicated course content. Perhaps Mobius or some other similar organization has a topic. As far as probe calibration for different materials if you can specify the exact material or provide a test coupon the probe manufacturer can provide a system with a proper calibration. You can also run a curve of gap vs. DC voltage and establish the...
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Re: Orbital Data Collection (Training)

ivibr8 ·
I did exactly as John stated in regard to calibration. In every field case using prox probes, I simply turned the probe in to touch the surface (0 gap) and measured the DC voltage as I backed the probe out say, every 1/2 turn (there is a little bit of slop so I lightly tightened the jam nut to fix the probe in place). You know the threads/inch so simply plot gap vs. voltage curve. The slope is the sensitivity for that particular setup (e.g. 209 mV/mil vs. published 200 mV/mil). This also...
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Re: Orbital Data Collection (Training)

Pump Guy ·
My thanks to everyone for providing me with valuable information.
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Re: Rollers turning sideways in agitator bearing

Big J ·
We have seen high thrust issues cause this type of failure very rapidly on fan sets.
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Re: ODS - wire model move, problem visualization

OLI ·
I used to take out the report and cut and paste amplitude/phase. Don´t over do it. You normally don´t need that many points for a basic structure if shape is a simple one. That is by the simple method with tacho reference and only looking at 1xRPM vectors at steady state operation that is. Keep track of sensor direction..... If you need the full modal analysis you may need the software tools to match. Olov
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Re: How important are asset taxonomy and coding?

candy ·
Are we going back to basics? It's still interesting and necessary though!
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Re: How important are asset taxonomy and coding?

Rusty Cas ·
I find that I usually have better equipment histories (of the machines I monitor) than my customers do, via "note codes" that I enter in my database as I make my rounds(new pump, new motor, new bearings, new base, etc). How can I get my customers to actually maintain good equipment histories, because many don't, in spite of having expensive asset management systems in place. "The trend is your friend"
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Re: How important are asset taxonomy and coding?

candy ·
If that's the case, I might consider the rotating equipment engineers to buddy your rounds. If there are many cases like that, are they still doing the maintenance philosophy of Don't fix if it ain't broken?
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Re: How important are asset taxonomy and coding?

candy ·
All those new things should be captured in the work order paper form or in the work order in the CMMS if used.
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Re: How important are asset taxonomy and coding?

candy ·
Has something been settled out of the forum?
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Re: How important are asset taxonomy and coding?

Amir Segal ·
There is Albert Einstein's quote which says: "Everything Should Be Made as Simple as Possible, But Not Simpler" So, how simple can you make your taxonomy before you start to loose valuable information? This depends on the goal for which you collect the data. For example, it can be interesting to compare failure rates of similar parts which are located at different sites. This entails keeping several hierarchy levels. Personally I never had to use 9 levels as depicted in the figure at the top...
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Re: How important are asset taxonomy and coding?

candy ·
The hierarchy should depict the actual plant hierarchy which could be plant, unit, packaged equipment, device/equipment/tag no. and parts.
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AMS MHM external connection

IgnacioFernandez ·
Good afternoon, I'm trying to extract data from magnitude and timing of vibration waves database AMS MHM. I tried installing the driver odbc but only lets me connect for Microsoft access. In a table I find the data I need but an OLE object, which can not extract this data. The idea is to achieve a method of automated data extraction and then fill them in another software. The webservice CSI Data Provider also gives me such information. Someone was able to extract data from the AMS for ODBC...
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Re: AMS MHM external connection

Dave Reynolds ·
http://www2.emersonprocess.com..._ru_InstallGuide.pdf There is a limited amount of software that you can extract too.....bottom of page 35
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Gear box data

AnibalM ·
Hi, I'm about to measure vibration on a Flender ZK-168-K4 gear box driving a cooling tower fan. Could someone help me with the data (# teeth, speeds, etc) ?
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Re: Gear box data

John from PA ·
You will likely have to gather this information yourself. Perhaps a spare unit exists or something in a repair facility where you can count the teeth? The Siemens site at http://www.industry.siemens.co...s/Pages/Default.aspx is very lacking in any specific information relative to Flender cooling tower drives. In addition, just knowing the model number usually isn't sufficient because any given model may come with several differing ratios.
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Re: Gear box data

John from PA ·
As I suspected, the site at http://www.industry.siemens.co...wergearedmotors.aspx indicates the ZK168 line is a double reduction and offers a range of ratios from 4.46 to 46.61.
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Re: Gear box data

AnibalM ·
Thank you John, Unfortunately, no spare units available. I'll try the site and look for some information with the owner as well.
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Re: Gear box data

John from PA ·
What is your motor speed? That tooth combination works out with an 1800 RPM motor to about 219 RPM fan speed. Not impossible to have that but seems high in my experience. I'm basing things on your profile which shows Brazil (60 cycle).
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Re: Gear box data

AnibalM ·
Z1=29; Z2=47; Z3=15; Z4=76 That's it.
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Re: Gear box data

AnibalM ·
Hi John, The motor speed really is 1780 rpm, 60 Hz. It is expected to have 216 rpm final speed.
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