It looks like this effort has once again stalled even after much hard work by several of the members.

I hope it can restart again soon.

FYI: I posted a duplicate challenge for a new Reliability Centered Maintenance Forum at the Association for Maintenance Professionals web site at http://www.maintenance.org

Membership is FREE and once accepted - simply click Forums to locate this project.

Again - I hope this effort and restart right here on the forum. Please let me know what I can do to re-energize this wonderful effort.

Terry O

This message has been edited. Last edited by: Terrence O'Hanlon,

Sorry, I have entered little late but it is a great effort.I will contribute to this forum to the best of my knowledge.
Should we start the process by selecting the modes first?

Hello Probin,

Thanks for your interest.
Looking forward to your contribution.

Start with reading the topic from start with the business case. Then review the failure modes and continue with adding/remarking the failure effects.

If you send a mail to rcm2study@gmail.com I will grand you access to make modification directly to the online spreadsheet.
Responding by this forum is naturally also ok.

Kind Regards,

Rogier

Rogier,

Do you already have a decision diagram or algorithm for the 2nd half of the analysis which is the decision worksheet ?

If not, email me at rollyangeles@rsareliability.com

and I will provide you one, this is the original version althought I made it in excell SAEJA1011

My Warm Regards,

Rolly,

I send you an email.
Would be nice to use a digital version of the decision sheet.

But first let's continue with the failure effects.

Regards,

Rogier

Come on guys - the Reliability world are waiting for the outcome of this virtual RCM..........lets see some results...........

quote:

RCM Analysis

It seems to me that RCM Analysis as you virtually demonstrated is mostly discussion and rationalization and as I have seen in reality, it is a management tool only. One truly skilled maintenance person as in the one that turns the wrench and greases the bearings has this skill to know when action is needed and what actions are needed. The one that bites you is most likely the one that falls out side the mean of RCM Analysis and that is where individual aptitude can and has improved reliability. Therein the best way to improve reliability and lessen operating cost is to dump all the management tools and invest and trust the skills in the one that turns the wrench and greases the bearings. It is a proven fact you can not program a maintenance person with a list of tasks like some PLC, if you do you will only have another dumb program.

Re: fin fan with gearbox and motor is there more parts, direction of flow, is the fan a variable pitch, what protects the bearing is there a slinger, what is the duty cycle intermittent or continues, is there lubricators or grease fittings, what type of belt V or cog, is there a tensioner on the belt …

One aspect of proper RCM - done with the involvement of the millwright - it doesn't replace his knowledge - it ensures that the care given that machine is carried on once he's left/retired etc.

This message has been edited. Last edited by: mike66,

Hello All,

Recently there was again an update on Failure Modes by Alfredo.

Information Worksheet 4.1

quote of the day
There's no difference between a pessimist who says, "oh it's hopeless, so don't bother doing anything, "and an optimist who says, "Don't bother doing anything, it's going to turn out fine anyway." Either way nothing happens.

Let's prove this virtual study can work by focusing on failure modes first.
When replying to this topic please give your opinion about these FM or add the missing ones.

A few to add before diving into the decision diagram ;o)

Regards,

Rogier

Ok, failure modes and solutions

Corrosion, rust and contamination this can be controlled. Pant can be used but must be applied properly because it masks damage until it is too late. The best that I have found is a spray wax, mix your own (wax, solvent, linseed oil and emulsifier) or buy the stuff in the aerosol can. This stuff can be easily removed for disassembly unlike paint. Bad part is that it has to be reapplied every year or two depending on the environment. Use a two piece slinger of sufficient diameter to keep contaminates reaching the bearing seals. The bushings on the fan and bearings must have particular attention. I have found that the trusted never seize Never-Seez can turn to Always-Seez in some applications such as a CIP with chlorinated caustic, dip them in wax if need be. V-Belts, get rid of them because they rely of friction. Salt spray is a lubricant and when it dries it is an abrasive. Use a cog belt with an occasional application of belt dressing or use a dynamic coupling. Use lubricators instead of grease fitting, chances are that this fin fan is subject to weather and weather typically messes up PM schedules. Have a reserve in the lubricators so they can be filled when the weather is good. Find some way working on these without down time. Use a spray of water or cross connect some or all the units. Heck, I could write a thousand page book on this… I think I like the old way, see a problem and fix it, no RCM Analysis needed and pass this knowledge on to your apprentices. You do have an apprentice program, don’t you?

Old Millwright,
I agree that you can’t replace good old know-how and experience. There is validity to consistency though. I’ve seen so many times that the same job is done different ways by different persons. Sometimes even the same person does it different ways at different times. Some people maintain equipment with their perceived ideas and never check the manuals or job plans, others like to go by the manuals. Some of our most talented techs prefer detailed job plans when given a choice. Others who are also in the most talented class of techs hate any detail in job plans. I say consistency allows for good baseline comparisons of whatever comparisons you’re trying to make.

I’m not a fan of FMEAs in real life practice, but I do see value in its concepts. People sitting in a room might guess all the failure modes they and think of, but in the end, the equipment does what it will. Maybe the group guessed it, maybe they didn’t. There’s no real consistency to the FMEA process either. It’s as subjective as the FMEA group and the facilitator.

I think it best to staff both a Reliability Group and Planner Group with some percentage of inside maintenance technical staff with inside equipment know-how. The Reliability and Planner Groups aren’t for every floor tech, that’s for sure. But there are some out there who see some logic in it, would like to give it a try and see it as a hopeful future. That’s me I guess. There is a lot to learn about equipment reliability as a craft.

Our plant was set up with equipment manual recommendations and floor technician know how for job plan tasks and PM frequency. Was there room for improvement? You bet. In the end, I think all of our groups have respect for what the other does.

You put a lot of quick shots out there for design and maintenance. Somehow, that needs to be quantified into an actionable plan. That's my view of it.

Hi all,
I've taken the liberty of transposing from Rogiers spreadsheets onto an RCM database to give a clearer picture of where we are at.
Rogiers done a fine job in getting the info down - this should allow us to progress a little faster.

Steve - we are assuming maintenance people are happy with everything as it stands - in particular failure effects and how things happen at Ollies Olifines when there is a breakdown? Is there anything you might want to add?

Mike.

Ollies_Fan.pdf (410 Kb, 43 downloads) RCM Database

RE: Ollies_Fan.pdf

Failure Mode (cause of failure) #1 is a bit off

Deduction from the installation of an accelerometer indicates a modern installation controlled by a PLC. Therein the PLC sends and receives the parameters, tachometer RPM to the HMI and the RPM request to the frequency drive. A less then and grater then statement using these two parameters can be used to monitor slip angle thus shutting down the motor preventing catastrophic failure and alert the operator to immediately call maintenance. Because there is a frequency drive there are a number of fault parameter for such thing as phase imbalance and on some of the more fancy ones have an adjustable ground fault. Or you can install a separate motor monitoring system if these parameters are not available on your drive or if you are using contactors. Therein the (cause of failure) could also be improperly set parameters or protection is missing.

One more at the risk of sounding hypercritical… This is likely a TEFC motor and you are highly unlikely to smell a burnt motor winding, maybe some cooked paint.

Oops, on number two… 2hr to change motor according to #1 and 6hr to repair? Heck, the boss is not going to like that. Bet you don’t do that again… and…

Old Millwright.
Great to have your input. Love your comments. They are right in many ways. Question is - what happens when "old millwright" retires and the new young bucks move from site to site and dont know the detail? If you have Old millwrghts knowledge on paper, many people can learn. If you keep it stored in your head, then it is hard to access.

Re:
fin fan with gearbox and motor is there more parts,
What you see is what is part of the scope of the analysis.

direction of flow,
The flow goes up.
is the fan a variable pitch,
The pitch is fixed.
what protects the bearing is there a slinger,
The fan shaft bearing is a sealed bearing.
Not sure about the bearings in the gearbox... what is standard with these bearings?
Motor bearings are sealed.

what is the duty cycle intermittent or continues,
Fan runs 24/7

is there lubricators or grease fittings,
No... No lubricators or grease fittings.
Bearings are sealed with the exception of gearbox.
what type of belt V
One V belt for the sake of the example
or cog,
is there a tensioner on the belt …
No auto tensioner - belts can be tightend by adjusting the position of the pulleys / sheaves.
Rgds
RCM Team Members

This message has been edited. Last edited by: Steve Turner,

This is a low tech fan.
tacho is only needed in the case the belt breaks or comes off. it sounds an alarm if this happens.
There are no other smarts except for vibration switch and thermistors in the motor.

quote:

Deduction from the installation of an accelerometer indicates a modern installation controlled by a PLC. Therein the PLC sends and receives the parameters, tachometer RPM to the HMI and the RPM request to the frequency drive. A less then and grater then statement using these two parameters can be used to monitor slip angle thus shutting down the motor preventing catastrophic failure and alert the operator to immediately call maintenance. Because there is a frequency drive there are a number of fault parameter for such thing as phase imbalance and on some of the more fancy ones have an adjustable ground fault. Or you can install a separate motor monitoring system if these parameters are not available on your drive or if you are using contactors. Therein the (cause of failure) could also be improperly set parameters or protection is missing

Hey guys... some great work.
The analysis has been done after working hours and the team is back. The team has the following to offer.

1A4 Coupling fails due to fatigue
Dominant failure mode is rubbers wear.
1A8 Door switch fails for any reason
Door switch is a microswitch and the contacts are normally closed. To activate the switch the contacts need to open. If it fails in almost all cases the failures are hidden. The only way the fan will shut down is if the wiring open circuits.
1B2
Belts fail for many reasons:
Normal wear
Accelerated wear due to poor pulley condition
Incorrect installation – misalignment
They stretch after installation
Delamination
Manufacturing defects, normall associated with the joint.
I will post the relevent failure pattern and data when the time comes.
1B3 The locking device failure will not stop the fan on its own.
The lock is there to prevent the blade coming off if the hub nuts are not installed correcty
10A1 Door switch fails for any reason.
Dominant failure mode is the plunger sticks, followed by the switch seizes closed followed by the spring fatigues.
The plunger sticking is by far the biggest problem.
12A1 Vibration switch fails for any reason
Vibration switch failure is usually associated with spring fatigue or internal parts sticking due to moisture and corrosion. Both equally likely.
14A1 Tacho fails for any reason
Tacho fails because the pick ups (targets) come off or the bolts holding the proxy come loose and the proxy fails to sense the pick ups.
Regards
RCM Team

One other thing. Thermistors are a closed switch. If the thermistors fail, they fail open circuit which shuts the fan down.
They can fail closed but this is extremely rare.

I guess firstly hi all as I am new to this forum and this is one of my first threads here so hopefully I can put some new spins on things for all the readers and offer some challenging views.

So lets get things started...What will this achieve by comparing methods? We will probably end up with a similiar maintenance strategy and argue about whether it is the right one or not for some time and during this time, life still goes on in the asset and it will be out dated before it gets implemented? How long has this thread been going for?? (just over 4 years )

In my experience I have perfomed many RCM studies using the majority of software and methods listed above. In many cases I have been asked to a site to redo an RCM analysis because the software, philosophy or approach used the first time was seen as wrong by the asset owner. I remember one of my first RCM studies that was completed at a large petrochemical facility where after 2 years work with over 100 years experience in the room, ended up on a book shelf in a unused office....Does this sound familiar to anyone? Is it really the RCM approach that failed?

So I guess my point is that the RCM analysis needs to be implemented in a way that connects your CMMS so that the data it collects can be returned for useful decsion making. Many organisations set up their CMMS without considering what they are going to use the data for and rarely define clear work process for their reliability engineers. Reliability Engineering is at the end of the day the study of statistics related to the plant perfomance of your equipment so it is these work processes that should be focussed on to deliver continuous improvement over the asset life once the RCM strategy has been delivered. So where do these statistics sit in your CMMS, what are they and how do they link to your RCM?

This is typically the missing link with most companies who implement an RCM snapshot solution (current practice) and then find that over time things change and such static solutions no longer provide the desired perfomance. It is the reliability engineering processes that sustain the initial strategy and it is these work processes that become the reponsibility of the site reliability engineers over the asset life so that another RCM software or tool, philosophy or approach not need to use heavy resources again.

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

Hi Paulius
Weclome
Can you tell us what industry you work in - CMMS data value tends to vary across industries.
Also, the thread is only 9 months old... I think you might have mistaken the date the originater joined the forum as the date that the thread started.
The thread started 31 August 2007 09:09 AM
Rgds
Steve

Steve Turner,

Sharing information, the customary response from us old timers is “I don’t bother any more because they are going to do it their way regardless”. This seem to be more prevalent the in top companies. Likely the results from too many failed methodology programs like Kaizen, S5, TPS, RCM and so on. Factor in an occasional management of “my way or the highway” and you will find old millwrights are reluctant to write much. However, give them an apprentice willing to learn... Granted we may occasionally send a new apprentice to the boiler room for a bucket of green steam to clean something but it is all part of the leaning process that takes a long time. Yes, I am I writing all this down. Where will it end up and will it ever be use, likely in the trash and never used. Should someone go around and collect all this information, categorize it, and post it all on the net before it is lost for good, sure would be nice to see that?

Ok, it is “a low tech fan”. Next question is what costs more, upgrade the parts or replace as a unit or a combination of. I see every part listed can be upgraded, door switch replaced with a sealed reed switch, bearings replace with auto-lube, thermal switch replaced with a thermo-disk used in HVAC, rubber parts replaced with polyurethane, use a slinger to protect the bearings, bring the PM parts to the outside - belt tension and grease, use some spray wax and so on. Heck, why can’t you all list the failed part with an upgrade? Otherwise replace as a whole unit, rip out the old and drop in a new. Spray the heat exchanger with a fire hose or something so there is no shutdown. Caution; if you use a fire hose make sure you disconnect the alarm system. Heck, I found it a bit humorous but the boss didn’t.