Have anybody used FMEA successfully for reliability purposes? Any success stories or pitfalls? Appreciate inputs for knowledge sharing purposes. TQ

Josh,
You are referring to Failure Modes and Effects Analysis, aren't you?

FMEA is one of the main steps in the process of Reliability Centered Maintenance. It helps to determine if the consequences of component functional failure are critical to operation, safety, or the environment.

The shortcoming of FMEA, if you want to call it that, is that the decision on failure criticality is subjective. Different experience levels between analysts could result in different criticality decisions on identical equipment.

I personally prefer Risk Based Analysis (RBA), which enables you to risk-rank equipment by considering the aggregate of failure detectability, likelihood, and consequence ranking. The resulting equipment risk priority numbers are sorted from high to low and a critical/non-critical cutoff value is selected. The equipment above the cutoff is considered ˜critical' and those below ˜non-critical'.

Regards,

Would Risk Based Analysis (RBA) be the same as Risk-Based Inspection (RBI) & Risk Based Maintenance (RBM)? If so what are the origins, distinctive concepts and procedures for such?

As I am a RCM practitioner and a beginner,
I realized that FMEA is a tremendous time consuming procedure for all assets(2,271 equipments )in my case even it is very good method.
So I developed a shortcut using a excel sheet for FMEA completion and modified to my situation. Maybe it's not special and already known method for anybody.
Just easy to do but useful.

It is very quick such as quick sigma.
It spent just 1week for a training crew who fill up blank on the sheet and for completion FMEA.
Now people are satisfied with the result.
And I am in the stage of generating proacitve task in MAXIMO.
Check the attach.

fmea.JPG (100 Kb, 106 downloads) FMEA&LTA overview

Thanks for sharing Dae. Can I see your shourtcut FMEA table to get the statistics that you attached? TQ

You're welcome. Josh.
I am still not confident what i am doing is whether appropriate or not at the RCM point of view.
In my case, I think there are not enough crew size to do maintenance jobs.
My crew do too.
SO why I make an excel sheet and try to develope so called "quick RCM".
I don't want to give a big burden to them.
Refer to the attach.

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

To_josh_from_daeil.xls (712 Kb, 73 downloads) FMEA&LTA excel worksheet for quick RCM

Dear L Johnson, yes we are trying to use FMEA with criticality, however still not sure whether this exercise is really worth to do. Any success stories?

To Gaspardk, I heard RBM originates from Exxon, am I right. In our case so far we only use Capstone/API RBI for static equipment. Your question is interesting and I guess only those who have used these methodologies extensively can differentiate them clearly. Have done any comparisons which you can show to us? TQ

The FMEA process has some value when it comes to determining the possible causes of failure of equipment. I have personally used FMEA techniques to narrow down the possible causes of a pump deterioration in hydraulic performance to two potential causes. I don't always think the analysis is helpful when you are dealing with an obvious problem, but it is very helpful for some equipment problems.

Charlie Martin

It depends upon the process used for FMEA. Personally, I try to follow some type of standard. In cases like this, I will normally follow a military standard such as:

MIL-STD-1629A: "Procedures for Performing a Failure Mode, Effects and Criticality Analysis."

I generally find these documents provide a detailed outline and process that is quite inclusive.

I also use FMEA in both directions. The FMEA provides information that I require when performing an RCM analysis and a maintenance effectiveness review (MER); It also provides the information I need for troubleshooting and root-cause-failure analysis.

It is a large file, so please feel free to contact me for an Adobe Acrobat copy. howard@motordoc.net

MotorDoc,
Please do me a favor share with me the documents.Thanks!
I have mail to you and surfing your net,it is nice site.

Hi daeil,
can you share with me the english version of your FMEA<A excel worksheet for quick RCM.
my email address is :ramonbaixf@hotmail.com

best regards!

I had a number of requests for the MIL STD on FMEA entitled:

MIL-STD-1629A "Procedure for Performing a Failure Mode, Effects and Criticality Analysis"

This can be downloaded from:

http://www.motordiagnostics.com/presentations.htm

I have also included MIL-HDBK-2173: "Reliability-Centered Maintenance Requirements for Naval Aircraft, Weapons Systems and Support Equipment"

If you have any questions on the application of either, please feel free to contact me: howard@motordoc.net

How is the MIL STD FMEA different from SAE FMEA? TQ

Josh:

The SAE J1739 provides design and applied machinery FMEA requirements. The primary difference between the military and SAE FMEA relates to how Risk is determined for selection of practices.

Other than that, the process is similar. In each case, it still depends on the intensity of FMEA that is required.

I have been presenting iPresentations on motor management programs: http://www.reliabilityweb.com/forms/tsol_reg.htm

In the present one on performing a maintenance effectiveness review, I discuss Risk using the NAVSEA scoring method. I had covered the RCM process and FMEA in a previous presentation.

In effect, both methods are similar and can be effective if properly applied. I just find that the MIL-STD's related to FMEA provide an easier to understand set of explainations and methods.

Guys -

Please use community standards of respect and civil language.

Debate is fine and diverse views are encouraged however respect and civility are the rule at MaintenanceForums.com.

You guys will scare everyone away from expressing themselves.

Sorry to let this post rage on unchecked as I am loath to intervene as this board belongs to the members - and I am not anxious to play the censor.

On a personal note - I happen to know both of the combatants here and both are professionals who are very passionate about the way forward. Both have specific areas of expertise and both have much to contribute.

I wish to invite both to remain as contributing members of the forum - just remember we are all just trying to find information that will help us do our jobs better.

Let us know what we should do as maintenance and reliability professionals - keep what you think of each other off the board.

Enough of these fireworks - I am off to set off our own fireworks in our back yard now!

Thanks and Happy Independence Day!

Terry O

Daryl,

Again, I make the request of you, Howard and any other poster on the forum - please be civil and respectful.

No one is interested in the personal debate - forum members simply hope to pick up some advice they may be able to put to use.

The great thing about this board and posting is that it comes from choice - to do so or not.

My advice to you and anyone else on the forum: stay focused on helping people by sharing what you know and do not worry too much about anything or anyone else.

Terry O

Josh,
Huge topic indeed!

In France, Aeronautics & Space Industries, Defence and Automotive Industries among others are using FMEA or FMECA in FEED / Design stage to improve reliability early in the system lifecycle.
The most common pitfalls I've found are:
- Lack of definition of the system breakdown
- Lack of clear definitions and sometimes overlap of "failure mode", "cause" and "effect(s)"
- Lack of clear definitions as to which phase of the system lifecycle or operational phase FMEA is made

System breakdown does matter as a failure effect at a given level of system breakdown can be a cause of failure to the next higher level.
If you link FMEA with maintenance activities, it's also important because then you need a clear policy of what is repaired at field level or at repair shop level.

FMEA / FMECA can serve various purposes: reliability/availability, safety and / or maintenance; according to the focus, the description of the effects can greatly vary.
If you're interested in reliabilty, your focus would be on redundancy where for safety you would rather look whether the design embed detection and mitigation devices. For maintenance / inspection applications, the focus is put on whether the failure can be anticipated so as to prepare for the relevant strategy. Of course, the boundaries are not fully hermetic between all these applications.

Automotive industry is the only one I know (Valeo and Magnetti Marelli for example) which uses various types of FMEA / FMECA.
Apart from the "traditional use" where FMEA is performed to analyse the effects from the end-user perspective, automotive industry is also using FMEA as a "design review / verification" process.
In this application, component failure causes are all related to design: material selection, spec. definition, choice of components (over or under-rated), etc. Failure effects address non-compliance with spec. and regulatory issues (like safety or environment). At the end, the automotive industry uses FMEA for specifying the tests to be performed in the factory.

The Defence industry has also extensively used FMECA and recent examples I've seen cover the use of FMECA for evaluating the coverage of built-in tests; most systems rely on built-in tests for maintenance purpose (of Line Replaceable Units - LRUs) or safety checks during operations. Matra company is even using it for specifying tests in repair shops when LRUs go back to shops for maintenance (Shop Replaceable Unit - SRU) which can't be done at field level because of spare policy / allocation, specific tools or simply the level of trade required required for maintenance performance.

Hope this helps.
Best regards
Bernard
PS: I've the RIMAP doc. you ask but need your individual e-mail address. Cheers!

There is a top down approach that is very practical and useful. It is much like the method that Larry described.
It is a Simplified Failure Modes and Effects (SFMEA) developed by Keith Mobley.

The end result is a Risk Priority Number or RPN as well as a Improved RPN that is calculated after doing a RCM analysis. All this is used in conjunction with the Criticality Analysis. The most critical systems/components are considered first.

It provides a prioritization of the critical components in a manner that allows logical decisons to be made based on the risk. When used in conjunction with the RCM analysis you can see how to reduce your risks.

It's just a more methodical way of selecting which low hanging fruit to pick first.

Regards all,

Has Keith Mobley published the SFMEA? Or, is there somewhere it can be obtained?

Howard

I don't know if Keith has published it or not it is in Excel Spreadsheet format. However, it may be propriatary since it is what we use in teaching and coaching Reliability Engineering.

I'll check and see if I may send you a copy.