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Asset Condition ManagementPosts About vibration/alignment/balance
I.D Fan strange Balancing response
Registered Member Hello Kishore, I am very pleased at the amount of detail you have shared with us, I have experienced similar problems before but the cause was different in every instance. 1. Have you removed trial weights when putting in correction weights and is your system doing correction calculations based on removing or leaving on trial weitghts? 2. Is your tacho firmly achored on the magnetic base or whatever mounting method you use and your 0-degrees blade or mark inline with a reflector tape and... [ more ]
Registered Member Hello Kishore, I will send you the procedure. BTW. Did you check to see if the closely spaced peaks in your spectrum are 1/3x apart? Please see the attached doc file. Thanks and Have a Great Day, Ralph [ more ]
Registered Member Greetings Ralph Stewart , Thank you very much for your prompt response . "easy" 2-plane setup " -Please share the details of that procedure . [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Lobes Compressor (A headache!!!)
Registered Member Mr. CJ,You apear to be a sales person who has offered nothing of technical value to an old discussion! Walt [ more ]
Registered Member We offer blowers and pneumatic systems. You can see more info here: https://www.palamaticprocess.c.../pneumatic-conveying [ more ]
Registered Member HI Reliable Analyst, Can you share root cause of your compressor high vibration if it was solved ? Regards Imran [ more ]
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Asset Condition ManagementPosts About Ultrasound Testing
Ultrasound vs. Vibration Analysis
Registered Member Which failure modes can US detect but Vibration cannot effectively detect? Which failure modes can Vibration detect but US cannot effectively detect? Regards- Ali M. Al-Shurafa [ more ]
Registered Member Greetings Zach from BAMA , Ultrasound is a value added tool when we use with Vibration and Infrared Thermography but not an alternative to them . We can find bearing faults / Lubrication issues with it but can not find the root cause with it .For example Bearing damage due to misalignment .Integrated approach is the best strategy . [ more ]
Registered Member Maybe (just a suggestion), you need to revisit ultrasound through training to see how others in reliability use this technology as a complimentary tool? Best Regards, Jim Hall, CRL, Mister Ultrasound, The Ultrasound Institute.(next TUI Level I Jacksonville FL October 2021 [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
bearing failure analysis on a 900hp compressor motor deep groove bearings
Registered Member I was about to raise same thing Ralph related to obstruction of topic. It would be better to cut the cage and see the inner ring surface as well. IMO, It seems like abrasive wear due to inadequate lubricant and would be ended with spalling if allowed to run longer. Excessive axial load didn't allow lubricant to perform as it supposed to. Suggested lubrication frequency and quantity would be suitable for design load. However, Installation of asset, operations and behavior of the driven... [ more ]
Registered Member Looks like there was a tremendous axial load being applied, causing a heavy, 360 Degree contact with the outer race. Why are the pictures obstructed by the Topic definition? Thanks, Ralph [ more ]
Registered Member Thanks for the closeup pictures. Unfortunately they are not really sharp so hence difficult to see exactly what you describe in your text. You might want to review the document at Bearing damage and Failure Analysis [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
The sawtooth vibration behavior occurs after steam turbine running up to normal speed
Registered Member I have attached Exhaust Temperature & Inlet Steam Flow Curve of a Single Stage (Curtis) Back Pressure Steam Turbine where effect of Governor Valve movement on Exhaust Temperature is more evident. [ more ]
Registered Member Hello lux You have mentioned no obvious relation with Differential Temperature b/w Upper & Lower Casing and also you have mentioned Casing Temperatures of 400-410 Deg Celsius. May I ask how Casing Temperature is measured ? You have mentioned current behavior is not related to Process Loading. May I ask if the Turbine Inlet Steam Flow remains constant from the time Vibration fluctuation starts till the time it is vanished ? During Startup Temperature within Steam Turbine changes sharply... [ more ]
Registered Member Hello Dear All- Thanks for your kind comments above. For the casing expansion----Actually this was measured duirng the commissioning (at the beginning of this year), didnot find an uneven expansion from the readings of several dail gauges at that time. Also as I mentioned above, the vibration behavior is not related to starting mode. Even for hot start ( Time interval between shutdown and restartup is less than 1 hour), the temperature of casing compared to normal operting basically was same... [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
what is insensitivity check as per API
Registered Member I don’t think there is anything that API defines as an “insensitivity” test. Can you site a link that uses that terminology? [ more ]
Registered Member Dear Sir, Earlier i asked about sensitivity test, But now it is insensitivity check, can any tell which clause no. in API or explain in detail. Ravishanker [ more ]
Registered Member It isn’t “insensitivity” check, it is sensitivity check and you asked the same question back in April. See https://www.maintenance.org/to...-system-with-a-rotor For the responses from back then. [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Machine age vs vibration level
Registered Member A bathtub curve graphically relates three types of failure: early, random (constant failure), and wear out . Manufacturing and material defects typically result in early, rapid failure of objects: that region of a bathtub curve is called infant mortality. new machine also can fail as above infant failures. So age /vs how the machine is operated with respect to its design /vs maintainability of the machine FFT Spectrum gives you instant healthiness of the machine so no need to trend the... [ more ]
Registered Member Your results may vary! If a pump is built with proper parts balanced and has the correct shaft clearances and runout it may exhibit lower vibration levels than it the new baseline. I was just involved in a pump that was rebuilt 4 months ago. It was installed without motor shims. When the coupling failed four months later, it was found to be over .080 high. The alignment was corrected and the levels were down but not as far as I would have expected. The gross misalignment had taken it's toll... [ more ]
Registered Member But in our case Malcolm, age is getting to be more of a factor, especially when we consider buying green bananas. Best regards, JGW (BN-MDS 100% retired) [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Motor shaft broken
Registered Member ''Just running your numbers with an assumption in that regard, the calculator indicates the power is excessive for (10) 8V belts so I reduced the transmitted power to 100 kW (the calculator provides that guidance). Doing that yields a static shaft load at the recommended tension of about 17,300 N.'' 8 belt for 100 kw trails taken what is the vibration reading post it in this forum [ more ]
Registered Member As mentioned the center distance makes a big difference on the required belt tension. If you can move the motor further from the pump you will get more wrap and will require less belt tension. This with proper number of belts may help reduce the failures. [ more ]
Registered Member I would not reduce the number of belts without some further analysis including perhaps establishing the load on the motor (Becar has suggested that earlier). As I've already stated: "There is a belt tension calculator at https://www.mitsuboshi.com/eng...alc_tool/v-belt.html that does a good job in calculating belt tension and static shaft load. One variable you need is pulley center distance. I had calculated, based on the belt length and pulley sizes you provided, a center distance of 2180... [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Cement Mill Maag Gear High Vibration & Sound
Registered Member ... [ more ]
Registered Member I see by a video at https://www.youtube.com/watch?v=qBffsEtiBh4 that this is a relatively complex gearbox. It incorporates an axial floating shaft that is the gear of the 1st reduction and pinions that also have some freedom radially. All this is being done to insure good load distribution. As Becar has pointed out the attached document has nothing about the behavior of this machine. So we need the proper document and preferably a list of the bearings and tooth counts to properly work out... [ more ]
Registered Member I suppose wrong document has been attached. [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Effect of using an extension bar to collect vibration
Registered Member If you use a pole every time data is collected the data will be consistent enough to identify any issues. Don't worry about it. [ more ]
Registered Member Thanks for comments and sharing your valuable experience [ more ]
Registered Member I have basically always used an extension pole since the beginning of my condition monitoring career. Best I recall, it started back in 1987. Seems like just yesterday. Like the ole saying, "time flies when doing something you enjoy". The pole I used was 4 1/2 feet at its shortest length and extending out to near 10 feet. Had a swivel ball connection at the transducer mounting end and a 90 pound "pull", dual rail magnet on the transducer. Never ever had many, if any, signal problems from... [ more ]
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Asset Condition ManagementPosts About Asset Condition Management
Cavitation in API process pumps
Registered Member Greetings Akashri, Mr. Kumar is correct in all the above, problem is now you have to determine which one it is and how to correct it. Most of the time I have found it to be a Engineering design issue by Turbulence, improper positioning of elbow, strainer etc.. but the best way I have found to determine this is by using an Ultrasonic leak detector head-set. Using this can help you determine the location of the cavitation then guide you to what you should be looking for i.e. bad pump seals,... [ more ]
Registered Member Greetings Akashri , Cavitation can form in any type of fluid transfer centrifugal pump . Cavitation occurs when air, steam, or thermal fluid vapors become entrained in the fluid. Fortunately, cavitation exhibits clear warning signs before it becomes a facility-threatening issue. Some of the symptoms of cavitation include Decreased flow or pressure: When a pump produces lower flow volume or pressures than expected, it may be a result of cavities forming in internal components. Noise:... [ more ]
Registered Member Sure, cavitation can take place in H/C pumps. Regards- Ali M. Al-Shurafa [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Increased vibration level at engine firing frequency!
Registered Member As much of my resource material is quite old, I unfortunately I don't have the phase diagrams for any V-type engines. You should be able to get that information readily from the engine manufacturer. It will tell you if the "5x component (firing frequency)" is a major or minor order. You might try contacting them yourself, again you need the firing order which you didn't supply. With regard to the phase diagrams see the paper at Torsional Vibration in The Diesel Engine . The content is very... [ more ]
Registered Member Thanks John, will go through the paper. Firing order is 1-6-5-10-2-7-3-8-4-9 [ more ]
Registered Member Thanks John, its a 4 stroke engine with 'V' type configuration. [ more ]
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Asset Condition ManagementPosts About Motor Testing
NO LOAD CURRENT UNBALANCE ISSUE
Registered Member I tested one 25 Hp L.V motor. In no load condition, the motor winding is showing 10% current unbalance.When I removed the rotor and do the current balance test for the stator winding,then found current unbalance only less than 2 %. Can someone explain this phenomenon. The supply voltage is balanced in both tests(less than 1 %) [ more ]
Registered Member Jan - Those are some fantastic experiments. This is very useful stuff imo. Where I work we occasionally take measurements, but we rarely have the opportunity to do controlled experiments where we vary one variable at a time to look at the effect. Regarding the unbalance experiment results that you posted 26 January 2010 07:24 PM – attached I summarized/analysed your results. In row 24, are the unbalances for each of 3 tests. The test with lowest voltage unbalance had lowest current... [ more ]
Registered Member It is not only the large DC current that creates the residual magnetism, as is shown below. And it is not the time that modifies the residual magnetism. The beauty of the following experiments is in the fact, that anybody can repeat them with very little effort. For the owners of the low voltage equipment, it is just few minutes exercise (if they have the guts to do it). I had a 200 hp, 460V, 1782 rpm, 223 Amp motor on the test bed for a load test the other day, so I had a chance to take a... [ more ]
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Asset Condition ManagementPosts About Motor Testing
Cryogenic Pumps(LNG Intak pump) Surge test fail
Registered Member Hello We always make these settings to the EARs of the surge test, as recommended by the manufacturer Megger baker: - LL EAR with rotor at 50%, due to the influence of the rotor - LL EAR without rotor at 10% - PP EAR always at 10% We always try to rely on the PP EAR, to diagnose, different responses between phases may indicate weak isolation between turns or shorts between turns, even when the comparison of waveforms comes out almost identical. I am attaching an example video of impulse... [ more ]
Registered Member I guess you may have tested the motor with the rotor still inside. The mutual inductance will cause the unbalance, quite common for what some people call a high influence rotor. Best to take the rotor out and re-test, cause a change in the rotor position will give a different P-P Ear value each time. Regards, Aditya [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
High spot
Registered Member The concept is similar for acceleration and velocity.. One must note that velocity and acceleration are not taken at the same location, since they are on the stationary component (unless using a shaft rider). More or maybe less, if the displacement has a 100 degree lag, the velocity should have a 190 degree lag - except that they are not the same measurement location. [ more ]
Registered Member You might want to read the content at https://dam.bakerhughesds.com/...ing-machines-pdf.pdf . Keep in mind that the high spot is the response of the rotor and that may vary as the rotor approaches and passes through resonance. There is also a “heavy spot”; that is a physical location on the rotor as opposed to a response. [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
fluidizing blower high horizontal vibration(what else can be done, running out of ideas?)
Registered Member Since the vibration is high on Horizontal and low on Vertical, kindly check the absolute phase first. Either it is steady or fluctuated. As looking to the spectrum, I assume it is unbalance issue same as Becar stated on 12/05/202117:26 . Looking at the pictures, since there is no room for in-situ balancing, please do shop balancing as speed near to operating speed. If cannot, need to interpolate the G limit accordingly. [ more ]
Registered Member Where about are you located? There are consulting companies that can help you with the data acquisition and analysis. You would need someone familiar with transient data analysis which is something Bently Nevada did very well.. at least back in the days when I worked for them :-). There would be a number of skilled folks out there who can help. Without understanding the problem it may be a hit and miss going through possible fixes plus the cost of implementing a solution that doesn't work. [ more ]
Registered Member at first, this blower are very delicate. the speed are very hight end every condition changed like pressure or pipe valve position can change the reaction. the maker offer you a specific design for silent-blocks. it depends about baricenter of machine, number of foot, type of elastic suspension. when we forgot one (too much difficult to mounting), the frame broken... normally the vertical reaction is less than horizontal, but not so much as yours. in vertical direction you have a floor, in... [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Is there any problem with my PeakVue Waveform?
Registered Member I use these three sets of parameter. the original from CSI. in according with the revolution velocity [ more ]
Registered Member I think the reason that it is useful to know the length of the waveform is to ensure that the lower frequency episodes can be seen. For example, in most cases the cage will do one complete revolution for each two and a half shaft revolutions. So if 4 cage revolutions are to be seen, then 10 shaft revolutions will be required. Ian [ more ]
Registered Member After looking back at old AP Sets (over 200) made by a client who uses wizard, CSI doesn't appear to default to a Special Waveform for Peakvue. Again, it is not wise to use order based Special Waveform options on Peakvue or Velocity on variable speed machines, as the HP Filter might go to a very large number and basically make the Peakvue and velocity waveform data not as useful had it been at a more useable lower number. As far as number of averages goes, I personally have used 1 average... [ more ]
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Asset Condition ManagementPosts About Motor Testing
High voltage winding test fails with the influence of rotor
Registered Member Thank you for the feedback! we will check the rotor centering and the clearance between the stator, also try to analyse or look at the closest possible points of contact to stator winding. [ more ]
Registered Member > Had there been some contamaination or debris found or some particles stuck in way of winding than when we test without rotor at that time also it should have been shorted to ground right? In my defense, I didn't know you checked again after disassembly, so I thought it could be slot section contamination or damage introduced during resassembly. ..But that scenario is ruled out since you found it good after removing rotor again (and stator slot section ground plane is relatively... [ more ]
Registered Member Thanks @electricplte for the reply. No.nothing has been changed since last test. Had there been some contamaination or debris found or some particles stuck in way of winding than when we test without rotor at that time also it should have been shorted to ground right? subsequently after test failed with installation of rotor and complete asembly, it was dimantled again and DC step voltage was carried out once again but test passed without any short to ground and leakage current found to be less. [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
GRADUAL CHANGE IN GAP VOLTAGE TREND
Registered Member Much of what I've marked has been presented or determined by the OP. [ more ]
Registered Member If You present only GAP-DATA, I do assumption that all other data are typical – they do not change. If You present (with the GAPs) only RPM, I do assumption that typical PROCESS VARIABLES do not influence the GAP CHANGES (including VALVE openings). If You do a presentation of some DATA – obviously information about Xdcer’s orientation should be provided (as You did it with a delay). One additional data which are important and are not provided: information about type of bearings (the typical... [ more ]
Registered Member Dear FSX, Apologies. When digging out this issue, I am getting many new information. I am just two month old in this plant. There are no SDs after 2018. Even in 2018 SD, they just opened the compressor top cover, inspected and closed it seems as they had some issues related to seal removal / its spares. I thought that the ESD will change the shaft property similar to electrical run out and the shaft position is not really changing. I could not understand why this extreme shaft position... [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Overhung Mill With High vertical Vibration
Registered Member If welding is ok, have checked for soft foot possiblity. Soft foot can also cause high vertical vibration. [ more ]
Registered Member I have looked over every inch of this mill. Cant spot any broken welds or loose bolts. Im thinking excessive clearance on the shaft/Bearings. Can that cause directional vibration like that? id think the horizontal and vertical should be close to the same displacement. [ more ]
Registered Member Have you checked any welding that may be involved with the mounting? I’m thinking perhaps a crack in a weld that might not make itself apparent visually. [ more ]
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Asset Condition ManagementPosts About Motor Testing
rotor bar analysis for motor operated valves?
Registered Member We can monitor changes in time-waveforms ! [ more ]
Registered Member If you are serious about MOV analysis, ask them to show you the Ultracheck M system. It uses thrust, torque, displacement, current & voltage sensors; required once to calibrate a valve. Subsequent analyses are done from current & voltage only. I believe it a big improvement over the old VOTES system from Liberty. Regards, Aditya [ more ]
Registered Member Thanks Aditya, that sounds like a promising lead. I fired them an email. [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Hump in an FFT spectrum.....!!!!
Registered Member These are clearly harmonics. Harmonics tend to make these humping patterns and it can be difficult to reproduce these in simulation, but thanks to some very good fortune I happened to simulate a distortion at 45° on a sine wave some time ago and got a very similar pattern. Notice that I mentioned the angle which is the crucial variable, that's Bullard Laws of Harmonics #2. The pattern of humps and notches is due to the phase angle where the distortion intercepted the sinewave. Everything... [ more ]
Registered Member Mathematically - oh that devil - one can show that pk >= rms. Take away some rms and the pk can go up. Example. Take a square wave. Low pass filter it (ideally) removing all but the first harmonic. The first harmonic has a greater pk or pk-pk than the square wave, but obviously it has a lower rms value because of the removal of the harmonics. I think that this has been discussed on this forum previously; someone may be able to find a link. [ more ]
Registered Member My point of view is that hump in FFT is multiple forcing function. The example that you present is a sine wave position, superimposed sine wave represent the raw data of waveform at diffrent direction and this will be will filtered to form sine wave for a better analysis,the hump in FFT with increase noise floor cause irratic or undirectional time waveform. Every forcing function have thier own time waveform to analyzed if it is a pure sine wave, irratic, undirectional etc. correct me if im ... [ more ]
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Asset Condition ManagementFor PdM Beginners Only
Vibration analysis for Pump at different pressures.
Registered Member Hello Dave, thank you for your reply. I have attached a cross section of the pump, the model i took readings on is a PFCS440, running at 1500 rpm These pumps are usually used with presses, but work great with other applications, so they the working pressure can continuously be changed, say 10 bar to 700 bar back to 200 bar to 300 and so on, just depending on what the customer desires. And it can also be left running at a constant pressure. Coupling is Flexible- Bush Pin Coupling Mounting:... [ more ]
Registered Member Vibman, I see you asked this question awhile back, I will offer some knowledge, attached example, 9 piston axial hydraulic pump, varying load every month, velocity data shows piston pass up and down when pressure increases/decreases. Same pump in operation for over 15 years. If you can provide additional details of make/model of your pump, how is it driven, operating speed, how is it mounted to earth, does the manufacturer have any vibration limits Dave [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Non-synchronyezed peaks at Main lube oil pump with BPFO defects
Registered Member Thanks for comment i gonna check the pump type bearing to confirm first and then we will make bump test to identify the Natural frequency of moto-pump. regards Anis [ more ]
Registered Member Dear ANIS VA , you have made a great consolidated report, from the data i am suspecting a pump bearing innerrace defect since, 8.56 is modulated with 1X, there are some cases we can get such strange frequencies with out matching with bearing fault frequencies. my suggesting for you to inspect any one pump bearings thoroughly [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Cat1 certification
Registered Member Re: Cat1 certification [ more ]
Registered Member Training hours should be part of the requirements. I have not seen them count real education in the subject. [ more ]
Registered Member I suggest you open the Certification Handbook at https://www.vi-institute.org/w...20-Cert-Handbook.pdf and specifically go to the bottom of page 9. [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
NSPECTR Manual
Registered Member Nspectr is still offered through Emerson's AMS Machinery Manager. But.. Will not be in the new AMS Machine Works software that is replacing MM. With that being said MM will still work like normal but there will no longer be improvements made to the software as the main focus is now Machine Works. It is nice having the artificial Art Crawford right at your side. -Chris [ more ]
Registered Member Don't know myself. I do know that the CSi brand is no more according to Emerson. You would need to approach them directly to see if they still support Nspectr. [ more ]
Registered Member Is the Nspectr program still offered and supported by Emerson-CSI? Walt [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Spikes in direct signal due to Possible Aliasing
Registered Member I no longer have the 3500 config software as I'm retired but as best I recall, the frequency ranges that are displayed (and user selectable) are a function of the transducer selected. In other words, should you select an accelerometer then you will be able to select a range that includes out to 10 kHz, or perhaps even more. Also, the best way to check for spiking due to electrostatic discharge is to view (with the 408) multiple direct orbits, and by multiple I mean 50 or more over a several... [ more ]
Registered Member Dear John, William & Walt Many thanks for useful inputs The Grounding Brush on Steam Turbine was connected to ground through an Ammeter. Ammeter resistance was found high and Grounding Brush was directly connected to ground and the Full Scale Spikes we were seeing in ADRE 408 DSPi vanished. However after some time we started seeing persistent increase of about 40 microns in Direct Value on all probes on ADRE 408 DSPi. However again there is no change in direct Vibration Value on DCS... [ more ]
Registered Member We both have a few "good" years at BN under our belt; even worked in the same office for awhile. I'll let readers determine the "good" years! [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Setting Parameters to Detect Misalignment
Registered Member Good morning, Flexible couplings can accept some misalignment before transmitting that force to the machine. As vibration analysis is the detection and measurement of force, then if the misalignment is not enough to impart a force to be detected then it cannot be seen in the vibration data. Thermal changes also play a role. If alignment is not measured while the machine is at normal operating temperature and compared to it's non-operating alignment then discrepancies can occur. Precision... [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
High 1x Axial at Motor
Registered Member was the case been solved? [ more ]
Registered Member Hi, in my experience when we have axial vibration on a fan like this or similar (belt drive for example), we check first the basement, to find if is well connected and the dumpers if have the same height, to avoid axial oscillation (like some table at restaurant) or you have to stiffen the baseplate (sometimes welding a X beam). [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
SCR Frequency
Registered Member I have 2 550kw DC motors, but the vibration is high when using 1 of these 2 motors. The spectrum show 300Hz at hight vibration motor (SCR frequency). Someone be able to tell me what troubles with hight vibration DC motor? Thanks! [ more ]
Registered Member As pointed out by others, it depends on whether the specific drive is six-step, etc. The real difficulty is that a LOT of drives out there particularly of fairly old vintage, get remarkably noisy, with respect to line frequeuncy generated vibration, at low loads, which can lead to confusion as to whether an SCR misfiring, etc. Another thing that particularly older vintage DC drives are senstive to is phase imbalance (voltage) on the input side....this can produce all manner of odd vibration... [ more ]
Registered Member Hi Jamie, Is this drive half wave rectified (3 SCR’s) or full wave rectified (6 SCR’s) You will always see electrical activity in the spectrum but I find it’s best to trend the values taking into account the loading e.c.t and don’t jump to conclusions, here is some info for you; DC Drive Problem Symptoms: DC Drive Problems typically show up on a vibration spectrum as amplitude peaks at multiples of FLine between FLine and FSCR. With a full-wave rectifier, this includes 2 x FLine, 3 x FLine,... [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Misleading inputs
Registered Member First of all the maker of the machine is the best source of information regarding alarm and danger set points. I also do not see any signs of ESD in the data you've presented. You might want to examine the document at https://dam.bakerhughesds.com/...-App-Note_R4-pdf.pdf and specifically page 13 (as numbered in the document). In the content you will find Mount the probes at the thrust bearing end of the machine and within 12 inches (300 mm) of the thrust bearing to minimize the effects of... [ more ]
Registered Member Any feedback regarding the above? The axial position alarm set points were adjusted with a very tight range. The cold axial float is 0.25mm, alarm set point is 0.25 and the danger is 0.38mm. I feel like it need to be adjusted to alarm 0.38mm and danger 0.50mm. AM I RIGHT? [ more ]
Registered Member Mr. John, I tried to gather more data as i can to determine the spiking in the orbit plot and the shaft centerline behavior. please see the PDF file attached. Regarding the probe mounting I couldn't get a solid answer to it. For this time I was able to get the steam parameters across the stages and all of them concluded that the rotor should move away from the probe. Inlet pressure: 41.1 Bar After 1 stage pressure: 22 Bar Extraction pressure: 10.5 Bar After extraction pressure: 5 Bar Exhaust... [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
ID FAN VIBRATION
Registered Member Checked DBSC of coupling for axial vibration and fire horizontal vibration need to check any crack in impeller shroud area..or any foundation looseness.. [ more ]
Registered Member Were you able to determine the sideband frequencies around so many of the "harmonics", including the 14x bladepass frequency? Thanks [ more ]
Registered Member First suction is for motor non drive side the second is for motor drive side the third is for fan drive side and fourth for fan non drive side [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
Vibration limits for exhaust fan
Registered Member Thank you @Registered Member @Registered Member fan is operated by vfd motor through belt drive; nominal speed 800 RPM. [ more ]
Registered Member May we know the speed of the fan? [ more ]
Registered Member You might want to review the presentation at http://acc-usersgroup.org/wp-c...ibration-in-ACCs.pdf , especially the slides from #10 onward. Otherwise, perhaps think of purchasing the applicable ISO specification. [ more ]
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Asset Condition ManagementPosts About Infrared Thermography
Lower end IR Cameras: do you REALLY get what you pay for?
Registered Member The ultimate factor for any brand of camera in cost is resolution and temperature range. If your planning on using an IR camera for just walking by and doing closeup inspections and to just keep it in a tool box...you probably wont need that higher resolution camera. If you are planning on providing a service, or inspecting any targets that are far away such as high voltage electrical equipment, then resolution is your friend. To more directly answer your question, you get what you pay for... [ more ]
Registered Member All, I have used a high end Flir P-640 professional IR Camera for years, and after leaving that company I have used several different Fluke and Flir IR cams with good success since, mostly for industrial plant applications. As an Electric Motor Engineer with Level II training- (Not an Expert), I agree with Bob Berry above, in stating to have you understand your needs. Get the basics down first, then get ideas from potential customers about the needs such as typical distance to target, target... [ more ]
Registered Member It would also be good if some domain experts suggest some good models of FLIR /FLUKE (both are considered to be most prominent in condition monitoring fraternity) which can do well for machinery condition monitoring and generating good reports through SW interface. Hope this will not be offending to anyone. Thanks [ more ]
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Asset Condition ManagementPosts About vibration/alignment/balance
SSS Clutch High Vibe Shutdown at 20 MW
Registered Member Thanks for the update. We all learn considerably more when the resolution is shared. [ more ]
Registered Member I just wanted to say thanks for all the help! We found the problem to be that the feet had not been fully torqued by several hundred pounds! Runs smooth as butter now. I hope if anyone reports a issue like mine again this response will come in handy. [ more ]
Registered Member One of my engineers is talking to GE, nothing yet. What SSS wants is to have GE and Brush and themselves onsite to troubleshoot the issue, big dollars. I agree, SSS clutches are incredibly reliable, worked with them many moons ago. The proper channels are taking longer than i would like. I would like any info as to how a SSS clutch could act this way. Or any one who has perhaps had this event occur. [ more ]
See all 6 replies...

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