Has anybody used online performance monitoring for their machines or equipment? This is contrary to doing an ad-hoc performance test eg after plant or facility start up ie take readings & then do calculations using certain formula. TQ

Josh,

Bruell & Keir, the Danish company specializing in vib monitoring and other PdM methods have s system called Compass. In brief, it uses process and mechanical/electrical condition data to compute equipment degradation , e.g., by trending polytropic efficiency of compressors or heat-transfer coefficients of exchangers along with vib, pr. drops etc to predict failure.

It is a web-based system that can talk to your vibration monitoring panel and DCS, so remote monitoring is possible.

I did an incomplte trial on an offshore compressor, but this was cut short for various reasons. I understand that an Australian O&G operator has used it a lot. No doubt B&K can tell you more.

Rosemount in the USA was working on a similar system, but I dont know its status.

V.Narayan.

Searched the Internet but couldn't find Bruell & Keir's web page. There are so many people have used Compass in the net. TQ

Vee, there is another post entitled "Remote Monitoring and Diagnostics". Is this considered online performance monitoring? TQ

This message has been edited. Last edited by: Josh,

Josh,

Sorry, wrong spelling! It is Bruel & Kjaer. Go to

http://www.bkhome.com/ip_template.asp?upid=3894

for their home site. You may have to search a lot more.

What is the URL of
Remote Monitoring and Diagnostics.

V.Narayan.

The URL link is under Posts about Technologies nery and Techniques for Condition Monitoring. Somehow I couldn't paste the link here. Rgds

Here you go -

Remote Monitoring and Diagnostics post

Josh,

PESS looks interesting but not the one I was talking about.

V.Narayan

I searched in the Bkhome but couldn't locate the online monitoring therein. TQ

The growth of integrated systems has meant that the need for stand alone vibration monitoring systems has dropped dramatically. Vibration is just another parameter going into the DCS, although you might find some systems that extract 1X info as well. To make up this loss of revenue, many manufacturers of these monitors have expanded into 'performance monitoring', so ...you might want to check out the websites of 'well known' vibration monitor manufacturers to see how they have evolved their product range.. try SKF, Bently Nevada, CSI,etc.

I am not endorsing any of these products but I would suggest that the very last person you ask about the effectiveness of their system is a rep from a vendor. You really do need to get hold of an end-user (its worth a visit to their site) to really understand the pros and cons of what they have.

You should also remember that it is easier to spec such a system into a plant that is going to be built - if yours is an existing plant, you need to talk to site personnel/end users of systems that have been retrofitted to an existing plant.

Buzz,

What are the cost benefit scenarios for implementing online vibration monitoring as part of an integrated system. And for what type of plants?

Rgds

Josh,

A Google search on B&K Denmark Compass brought me this site on Compass; this is the system I mentioned earlier. It can integrate vibration and process info, run algoriths and predict time to failure based on your parameters.

quote:

Bruel & Kjaer

http://www.bkvibro.com/db/files/compass_6000_opc_client.pdf

Since it is web based, if you have enough bandwidth, remote sensing is feasible.

V.Narayan.

What are the cost benefit scenarios for implementing online vibration monitoring as part of an integrated system. And for what type of plants?

The plants I am most familiar with are oil and gas, petrochem and large power stations.

Online vibration monitoring usually refers to a set of standalone vibration monitors hooked up to transducers fitted to a machine(usually in accordance with an API spec): when overall vibration (sometimes other parameters) reach a cetain level an alarm is raised (e.g. annunciator in the control room)and if vibration continues to increase the machine is automatically tripped - these are machine protection systems and considered to be primary safety systems, an essential part of the control system of any large machine.

Piggybacking on these these are the true monitoring systems which can return trends, spectra, orbits, bode and polar plots - of course, its important to have as much info about your machines available as possible but it is only of any value if it is put to good use. I am really not sure how much cost benefit there is in these systems since for example, there are very few people (compared to the number of plants) out there who can really identify a critical speed and understand what a change might mean, so this information is largely wasted. Because of this, my experience of these system is that they are very useful in providing lots of information of 'what went wrong' after the failure, rather than being used to figure out how to deal with and manage an ongoing problem. Often, these systems cause more problems than they solve.

On one of our assets, the company that built the compression train for us, bought all of the transducers from reputable companies and instead of using standalone monitors, fed the vibration signals back to their own cards which in turn gives the overall levels back to the DCS which provides the neccessary protection (with the appropriate failsafes)- treating overall vibration as just another parameter, trended with all the others (temperature pressure etc) works well for us - we can access the raw signals for baselines, troubleshooting and regular monitoring and we don't have to devote huge volume of control room space to vibration monitors.

The best scenario (IMHO) is the one where overall vibration levels are fed back to the DCS, along with all the other parameters so that any changes can be readily identified.

We do actually have an online monitoring system somwehere (complete with an entire orchestra of every type and bell and whistle that you could imagine), but the company who sold it went bust, the computer (and OS) became obsolete and unmaintainable, so it was quietly removed - the general consensus is that we paid a lot of money to learn that these systems don't bring much value to our operation (despite the somewhat compelling sales blurb).

Buzz, I presume that the OS you are talking about is a Unix type?

Buzz,

Thanks for the reply, interesting stuff. But what are the actual costs/benefits that you achieved. It appears, if I understand correctly, that in one case you achieved none and were happy to get rid of it, and in another case the information goes unused.

Do you really think that there is no way of utilising this information in a proactive sense rather than the "after the event" scenario you mentioned?

Would you personally recommend online performance monitoring to others?

I have been involved in a few projects around this, and have reviewed some others. In one case, that of transco in the UK, I am aware that they greatly reduced maintenance via these technologies. Is there a chance for you guys to do similar do you think or is it seen as a white elephant there?

Rgds,

In my opinion online monitoring systems have their place, but the infrastructure (people/knowledge) most be in place.
An online system would function well in an environment that has already established a seasoned CBM structure (analysists, data colection, PdM practices) and most important credibility

quote:

there are very few people (compared to the number of plants) out there who can really identify a critical speed and understand what a change might mean

With MBA 's running Production area's the focus may shift towards replacing humans with technology, resulting in herds of white elephants

Buzz feeding the signals to the DCS is a good option, but the DCS is in most cases Operations Territory. You need at least a board operator who can spell maintenance

A DCS is great for analysing, but most likely it will be done the day after

This message has been edited. Last edited by: svanels,

It appears, if I understand correctly, that in one case you achieved none and were happy to get rid of it:

I wouldn’t say we were happy to get rid of it, it was more a case of costing a huge amount of money and delivering enormous amounts of information that was never of any value (because no-one understood it and it never contributed to any problem solving); when the system ‘died’ it was difficult to find anyone who could justify the cost of replacement.


in another case the information goes unused.
The info that goes into a DCS always gets used, if anything steps out of line, its gets investigated: comparison of trends is a useful tool in understanding some problems.


Do you really think that there is no way of utilising this information in a proactive sense rather than the "after the event" scenario you mentioned?
As always, its down to people – these systems are nothing more than tools – if people don’t know how to use them (or will not, for whatever reason: inadequate training or poor design) then they are wasted– there was an example on the previous version of this board where a compressor wreck occurred. This plant had an all singing/dancing online system in its own cubicle (where no-one ever went), situated next to the main control room which faithfully recorded all of the ongoing deterioration that occurred during repeated attempts to start the train. If anybody had had bothered to look at the information that was available an extremely large bill would have been significantly reduced.

Would you personally recommend online performance monitoring to others?

Absolutely 100%, if only I could find one that works and benefits me more than it does the vendor (maintenance/upgrade fees, “what you want will be in the next release etc etc). However, in many classes of machine, performance drops off gradually so a periodic check/calculation is often sufficient. If performance drops off suddenly, it is usually obvious

I have been involved in a few projects around this, and have reviewed some others. In one case, that of transco in the UK, I am aware that they greatly reduced maintenance via these technologies. Is there a chance for you guys to do similar do you think or is it seen as a white elephant there?

Here’s my cynicism coming to the fore: nearly all machines will need some sort of maintenance irrespective of what technology you have at your disposal. Can you give some examples of how transco cut their maintenance using these technologies? What did they do differently to get the reduction - is it possible that the decision to adopt a new approach/technology triggered a review/comparison of what was being done against what actually needed to be done, allowing removal of a good deal of unnecessary/redundant effort?

Buzz feeding the signals to the DCS is a good option, but the DCS is in most cases Operations Territory. You need at least a board operator who can spell maintenance:

I have found that operations personnel are the front line 'eyes and ears' of maintenance efforts e.g. this doesn’t sound right, there’s a leak, this machine is running faster/slower than normal, this bearing temperature has increased – information such as this is invaluable and will rarely if ever be obtained from any online system. I guess I‘ve been very lucky – most of the places that I have worked have had a good team spirit and ops and maintenance work well together. I have always encouraged my team members to interact with ops people on a daily basis to find out what is going on, listen to their concerns and try to address them. Sitting back in an office waiting for them to come to you won’t work.

quote:

Sitting back in an office waiting for them to come to you won’t work.

I subscribe to that!

As I remember it, I was bitten by the condition monitoring bug in the mid 1960s after a maintenance manager said something like "there has to be a better way of maintaining steam turbine generators than just by opening them up every so often". He must have been looking at the overtime report, list of costly spares used, and the need to bring the machine off next weekend to fix up a heap of faults that had emerged just because of the outage.

My boss at that time took up the challenge, and we developed Valves Wide Open tests (later formalised in an ASME Code). Later at other plants, we developed these tests to advantage. The method requires some calibrated test instrumentation, and I think is really too expensive to use more than yearly.

This year, I reported on experience with a 500MW unit where its DCS enabled useful CM results that compared well with accurate tests for overall condition. This was at ICOMS2005 last June. Copy of paper attached (how about coming/presenting at the World Congress on Engineering Asset Management in Australia, July 2006? http://www.wceam.com) Ray

Beebe_turbs-018.pdf (154 Kb, 21 downloads) Turbines CM paper

How about an answer or discussion about the following?

I am specifically interested in finding out if 'technology' really did reduce the maintenance effort (and how) or whether the impending implementation of 'technology' caused a review of what was being done allowing unneccessary/duplicated effort to be removed


I have been involved in a few projects around this, and have reviewed some others. In one case, that of transco in the UK, I am aware that they greatly reduced maintenance via these technologies. Is there a chance for you guys to do similar do you think or is it seen as a white elephant there

Here’s my cynicism coming to the fore: nearly all machines will need some sort of maintenance irrespective of what technology you have at your disposal. Can you give some examples of how transco cut their maintenance using these technologies? What did they do differently to get the reduction - is it possible that the decision to adopt a new approach/technology triggered a review/comparison of what was being done against what actually needed to be done, allowing removal of a good deal of unnecessary/redundant effort?