For those who have the book on John Moubray page 302 states : Quote

There is often a tendency to focus too heavily on primary functions when assessing maintenance effectiveness. This is a mistake since, apparently trivial secondary functions often embody bigger threats to the organization if they fail than primary functions. As a result,
every function must be considered when setting up maintenance effectiveness measures and targets . . . . .

I agree on this statement, no questions

Page 304 on RCM2 Book by John Moubray

The OEE as defined above only relates to the
primary function of any asset. This is misleading leading because as in the case of the gasoline storage system, every asset, machine tools included have many more functions
than the primary function and each of these functions have their own unique performance standards, Consequently, OEE is not a measure of the overall effectiveness at all but only a measure of the effectiveness with w/c the primary function of the asset is being
fulfilled. . . .

This I somewhat disagree, let me lay down the facts as practicioner of TPM for more than 10 yrs.

1) OEE is the primary measure of TPM
2) The activities of TPM will ensure that secondary functions are being taken care off
3) Autonomous Maintenance pillar will take care of slight defects and abnormalities whereby taking chance of screeing secondary functions that ain't working
4) Planned Maintenance will restore equipment by bringing back failed primary and secondary functions.

TPM activities by the different pillars will ensure that both primary and secondary functions on the equipment will be addressed to achieve their OEE goal.

Although, TPM have a different term, Primary function in TPM refers to Function Loss and Secondary Functions refers to Function Reduction loss. Function reduction loss are failures of secondary functions wherein the equipment is still capable of running.


Regards,

Rolly Angeles

This message has been edited. Last edited by: Rolly12,

Rolly, I think what John was saying was that OEE can only define the state of the primary function. You can still operate an asset with a high OEE in the primary function but this figure does not reflect the performance of any of the secondary functions. EG: I can have a powder carton filling machine operating at 80% OEE but if it is leaking powder all over the place this secondary function OEE is obviously well below that.
Yes you are right when you say the displines of TPM when applied correctly should be preventing this from happening, however it is more a theoretical point than a practical that John is trying to empahsize.

Mike.

Sorry I mean secondary function performance standard - not OEE.

M.

Rolly, Mike,
The KPI called OEE measures that of the primary function (only), as pointed out by Mike. Rolly you are quite right in stating that TPM practioners will automatically ensure that secondary functions are addressed. True, but you dont measure them. One could argue that TPM practioners will take care of primary functions too. So why measure OEE?

I have seen situations when pump bearings that run hot are kept cool by blowing air or pouring water over the housing. This will perhaps help OEE, because you can try to find an opportunity window some time later, to minimize lost production. Similarly, if a mech seal leaks slightly, you can collect the drips in a drip tray and keep the OEE up. What does it say of the behaviour, and possible reliability trends in the facility?

Vee,

here's my advise, If you will measure OEE without applying TPM then its useless and pointless.

if you are going to measure OEE by applying TPM then we dont need to argue since secondary functions will be addressed.

In your statement I think these plants dont perform TPM and just measure OEE.

my 2 cents,

Rolly Angeles

Here is how Tomo Harada of Toyota replied to the question "Do you measure OEE?":

No it is not a good management metric for us. It is a good spot analysis tool for use some times. OEE has several flaws from a practical point of view. Anytime you measure six things and multiply them together to get a number, there is danger. It is better to have six components understood and tracked individually. Otherwise you can't tell the difference between 75% OEE and 85% OEE. The former could be better if it was due to the production mix and number of changeovers. The latter could have fifteen percentage points of scrap for example, and be a total disaster.

Just thought this was interesting.

Hans,

Appreciate your feedback, although I personally respect your industry decision not to measure OEE. Althought what I am going to tell is not mostly found in TPM books and is well based on my 10 years of experience in developing, promoting, implementing and feeling the frustration and fruits of TPM.

First, the real reason why OEE is measured is to determine the loss your equipment is suffering and to designate the correct and most appropriate KPI's and Mean Indicators for the loss.

OEE is calculated using 3 variables as explained in any TPM book namely AVAILABILITY x PERFORMANCE RATE x QUALITY RATE. Now, literally what the Japanese had been saying is that they use the term availability but their formula is more of utilization. I have change their terms to OEE is Utilization x Efficiency x Yield. So it is much more convenient.

Once the OEE had been derived, your software or if this is done manually should always look upon in in 3 levels so that we know for a fact where are u suffering, will it be utilization, efficiency or yield. For example you are low on utilization now, a 2nd level OEE will indicate what losses seems to affect your utilization is it Breakdown, Set-up & change-over, cutting tool change, and so on.

If your efficiency is low what seems to be affecting it will it be the design speed or minor stoppages and so on.

After you have learn of the losses your equipment is suffering then a 3rd level OEE will let u understand to use an indivual indicator to track these losses as we improve upon them.

Lets say your utilization is low and breakdown seems to be affecting you, then you can either use MTBF, MTTF to improve upon the failure.

If you are suffering from efficiency and minor stoppages are affecting you, then you can use the mean time indicator called MTBA or Mean Time Between Assist.

From my own understanding and simple perspective what is important in measuring OEE will be to derived what are the losses your equipment is suffering and to designate the most appropriate indicator for each type of loss.

I hope this clarifies my point.

Rolly Angeles

Rolly,
You say,

quote:

if you are going to measure OEE by applying TPM then we dont need to argue since secondary functions will be addressed.

TPM followers choose to measure the OEE of primary functions. I am not sure why it is not important to measure that of secondary functions. Since TPM takes care of the latter, AND it also takes care of primary functions, so why measure only one set and not the other?

Perhaps the way secondary functions are treated are to be treated as a given, an act of faith. If so do TPM followers not have faith in the way they handle primary functions?

Rolly,
I'm not agreeing or disagreeing with anyone's view of OEE. I just thought Mr. Harada's statement was interesting. I can just imagine how many times he's been asked "why" some key metric was up or down. If the metric is OEE, which has several components, then each time OEE changes, each component must be analyzed in order to get at the root cause of things. I just think it is interesting that Toyota blows by OEE and goes directly to it's components.

Vee,


Sorry for the late reply I was busy lately. First let me define so we have a common understanding. Primary failures or TPM term call this Function-loss breakdown is a failure where the equipment will be stopped. Secondary failures, again TPM called this Function-Reduction Breakdown, is a failure of secondary functions in which the equipment is still capable of running.

It has been a common practice that majority of industries I know only tracked primary failures. While secondary failures are often left unrecorded for example a pressure gauge is missing or broken, they will not record this as a breakdown. They only consider breakdowns which will halt the equipment which are primary failures. I totally agreed with you and Mr. Moubray that OEE deals only with what you call the primary function of the equipment, but the point I would like to clarify as a practicioner of TPM is that I just wish that Mr. Moubray (I heard that he passed away ) should also state that although OEE will only address primary functions, TPM Pillars such as Autonomous Maintenance and most specially Planned Maintenance will address these secondary functions through their restoration activities.
Hence, I think you will agree on the following :

- That OEE will not address the primary function
- TPM activities will address secondary functions
- Achieving OEE of 85% is not the real goal of TPM but understanding that the 3 components of OEE should be satisfied which are Utilization x Efficiency x Quality Rate. There is no reason to celebrate when you achieve an OEE of 88% if you have severe leak in your system and your Quality rate is at 90%
- OEE is measured to determine what loss the equipment is suffering,

Vee, I do not know of any KPI, or indices that can measure secondary functions, most maintenance indices, MTBF, Breakdown Rate, OEE are geared on measuring the primary function of the equipment. Do you have a measurement for secondary functions ?

My Warm Regards,

Rolly Angeles

Rolly,
#

quote:

Vee, I do not know of any KPI, or indices that can measure secondary functions, most maintenance indices, MTBF, Breakdown Rate, OEE are geared on measuring the primary function of the equipment. Do you have a measurement for secondary functions ?

Not in TPM terms, but certainly in RCM terms. For example:

A pump's primary function is to transfer X litres of liquid with a pressure difference of Y barg using Z KW of power. If it misses any of these measures, it FAILS, even if keeps running in OEE terms. As a TPM person you may say that autonomous maintenance will take care of it; possibly, but the whole purpose of measuring something is to make things transparent, not depend on good faith alone.
One secondary function is to contain the liquid. So if the seal or flange gasket leaks, the pump has FAILED, even if it can continue to physically run and perform its primary function. The pump MTBF will be therefore reduced because it has failed to meet one of its functions..
Secondary functions are not unimportant also-rans; sometimes they are more important than the primary ones. For example,
1. A Crude Oil Tanker's primaty function is to transport crude oil in time and with a given fuel consumption for the trip in question.
Its secondary function is to contain the crude oil. This function is arguably far more important else we may have an Exxon Valdez scenario if there is a hull leak due to say, corrosion.
So your example of pressure guages is not very appropriate because it trivializes secondary functions; in fact some pressure guages fall under the category of superfluous function.
2. The insulation on a hot steam pipe is primarily to prevent heat loss. If there is a fuel oil line running over it, a secondary function of the insulation is to prevent any oil leak from above resulting in a fire.

Dont get me wrong. I support TPM and OEE. In a production line scenario, the primary function may be significantly more important, so you measure OEE. But in other situations, as illustrated above, it does not always paint the full picture. In these cases measuring performance for non primary functions may also be important. I think all that Moubray was saying was that OEE does not tell the whole story in every situation.

I hope you can agree that he was right.

Hello Vee,

I'm beginning to agree with you that Moubray does not tell the whole story in every situation, my impression with Moubray's interpretation on OEE was that I think he was/is hateful of something Japanese.

There are lots of best practices from the east and the west, and I do not confine myself on one culture but I try to cater them both as there are always good things to both side, in fact, I structured to used RCM in our Planned Maintenance activities since it fits perfectly in the later phase of the activities for Planned Maintenance.

As Steve pointed out some opportunities for improvement in the SAE JA1011 RCM Version, thats why he developed a streamlined approach on RCM he called PM Optimization. I learn a lot from these approaches, yet in the end it's your call on what to use, what is important is knowing the tools on best practices and when to correctly apply them in actuality.

Vee, let me tell you if what I know is correct, Stanley Nowlan and Howard Heap are instrumental in the formulation of the report on MSG for the airline industries, One of Stanley's student was John Moubray, since RCM use was for the airline industries, Moubray was thinking on how to adopt this to industries on land, so he tried to revise the decision diagram and logic tree to include environmental consequences.

Hope Moubray is still alive to join in this friendly argument.

My Warm Regards,

Rolly Angeles

Rolly,

quote:

Hope Moubray is still alive to join in this friendly argument.

Unfortunately, he passed away in 2005.

quote:

I'm beginning to agree with you that Moubray does not tell the whole story in every situation.

Sorry, I never said what you attribute to me, so I dont know what you are agreeing with. I said that John was right in his commment on OEE, and gave some examples to support my position.
I do not also subscribe to tour view that JohnM did not like Japanese inititives.
John was very thorough in his approach to RCM, and did not accept the flexibility that many others wanted, deviating from N&H's original thesis. Some see this as an attempt to prevent progress, others as retaining the ontegrity of the process. You can choose the one you like.
I have had several converstaions with John over the years. He held very strong views, and I have disagreed with him from time to time. But his insight was clear, structured and well researched, so while one may not always agree with him, he certainly knew what he was talking about. I always held him in great respect.

Yes, I too am a TPM practitioner of many years experience however I don't read anything in to Moubrays comments that would indicate anything against TPM.

Mike.

Guys,

I think that you will find that Mr Moubray was impressed when he read a TPM guru state that RCM was the next step of TPM. (But I am pretty sure his opinions had nothing to do with it being Japenese)

He also resisted streamlined forms of RCM for reasons of the integrity of the approach. If you read through any of his articles he states clearly, logicaly, and concisely why that is.

I have posted this here a number of times but think it is worthwhile posting again to clear the issue.

The_Case_Against_Streamlined_RCM.pdf (126 Kb, 21 downloads)

Any articles showing TPM improves bottom line results of companies outside Japan?

I never heard John Moubray say anything bad about TPM and I don't know of anything he published that was negative towards TPM.

I think he had much more to say about streamlining RCM as Daryl mentioned.

Dear all,

As we are talking about OEE I thought this may be a useful link to put here.

I don't know these guys but their system looks pretty good. (Watch the movie, not exactly Harry Potter but interesting)

http://www.oeetoolkit.com

quote:

He also resisted streamlined forms of RCM for reasons of the integrity of the approach. If you read through any of his articles he states clearly, logicaly, and concisely why that is.

Daryl,
The paper you refer to is highly emotive and lacks logic in my opinion... so much so that I wrote a paper in response and delivered it at several conferences around the world. Sections of it were also published in magazines.
I have attached an extract from this paper for those that are interested in an opposing view.

The_Case_for_Alternatives_to_Classical_RCM.pdf (172 Kb, 13 downloads) The Case for Alternatives to Classical RCM

quote:

I never heard John Moubray say anything bad about TPM and I don't know of anything he published that was negative towards TPM.

Delboy,
In the early days of RCM2, John Moubray was quite critical of TPM. It seemed he lessened his public criticism in later years. TPM and RCM have overlapping principles and both are compatible. What TPM of itself lacks, is the analytical framework that RCM provides. TPM needs RCM to be highly effective particularly in environments where there is a need for deep levels of maintenance not executed by operators.
Regards
Steve
www.reliabilityassurance.com