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When TPM says that failures and breakdowns can be zeroed out or eliminated, it simply means that the Mean Time Between Failure is lengthened and that breakdowns will happen but this time on a longer period or interval. Technically speaking, the breakdown was not eliminated, the MTBF was only prolonged. Zeroing out breakdowns is simply not possible in the real sense.

By Rolly Angeles

To answer this question directly and bluntly, the answer is “NO”. Breakdowns and failures are simply not possible to eliminate in your equipment and machines. For those of you reading this and practicing TPM or Total Productive Maintenance, they claim that one of the goals of TPM is to eliminate breakdowns or to zero them out in your equipment. The only time you can actually have a zero breakdown and zero downtime is when your equipment will no longer be used or decommissioned.

I was invited in Malaysia last May 2011, and participated on a maintenance conference in which I was one of the resource speakers during their morning session. My topic was about comparing “TPM vs RCM which is the Best Pound for Pound Maintenance Strategy”. I was discussing about the importance of shifting our maintenance focus from trying to eliminate breakdowns to eliminating or reducing the consequences of failure since in reality breakdowns simply cannot be eliminated in the first place. During the afternoon session, a speaker from TPM Club India was presenting about TPM and discussing about the possibility of eliminating breakdowns through the implementation of Total Productive Maintenance and was contradicting what I was discussing previously. If you were one of the delegates that attended that conference then there would be confusion in the first place on which side to believe.

First, let me clear them out to you, when TPM call them zero breakdown, it does not necessarily mean that there is zero downtime. Preventive Maintenance is included as one of their Planned Downtime. This means that when a part is about to break or fail in operation and maintenance replace them in advance prior to the actual failure and took them 30 minutes to replace then no breakdown is recorded but there is an actual downtime of 30 minutes. Downtime caused by parts replacement, PM shutdown and overhauling, and other maintenance activities will be included as part of their Planned Breakdown or Planned Downtime. If we speak about manufacturing plants, breakdowns are not the only cause of downtime, downtime can also be caused by assists or errors (TPM called this minor stoppages), set-up and conversion, start-up losses and cutting tool changes.

Second, the word Zero Breakdown is quite confusing and in fact very intriguing. If I have an equipment with a severe oil leak, a safety officer can declare the equipment fail for safety purposes even if it is still running. From a maintenance point of view when the level of oil is always below the minimum then they may declare the equipment in a failed state. Operations people may declare the equipment fail when it overheat due to failure of the lubricant. Therefore, before one can declare a zero breakdown, your maintenance and operations people must first understand what failures and breakdowns is all about and understand its diversity in the first place. Kindly click this link for a more thorough description of each failure and breakdown. Click Here!

A) Patterns of Failure

• Infant Mortality Failures - failures occurring at the beginning happens mostly right after a PM overhaul

• Random Failures - failures the occur at any given period

• Age-Related or Wear Out Failures - failures that will survive to the age or period specified

B) Classification of Failures

• Hidden Failures - failures that will not be immediately felt by operator unless a second failure happens

• Evident Failures - failures that will be known and become evident to operator

C) Types of Failures and Breakdowns

• Function Loss Breakdown - failures in which the equipment will totally stop

• Function Reduction Breakdown - failures in which the equipment can still run and produce output

D) Occurrences of Breakdowns and Failures

• Sporadic Breakdowns - breakdowns that result from a single cause that is easy to rectify

• Chronic Breakdowns - breakdowns that have a wide array of probable causes

E) Categories for Failures

• Maintenance Induced Failures - failures caused by maintenance people themselves

• Non-Maintenance Induced Failures - failures caused by other parties aside from maintenance

F) Stages of Failure

• Potential Failure - indicates that a functional failure is on the verge of occurring

• Functional Failure - inability of an item to meet a specific performance standard

G) Groupings of Breakdowns for TPM

• Planned Breakdowns - non - machine related downtime due to PM, meetings, lunch break

• Unplanned Breakdowns - machine related downtime due to breakdowns, assists and conversions

Third, in TPM Planned Maintenance, whether you apply it in Steps or Phases this will always be done two folds. The first few Steps/Phases of Planned Maintenance will aim in reducing breakdowns to a minimum or eventually zero them out but expect the breakdown to occur once again during the later phases/steps of Planned Maintenance. Once the breakdown repeats itself, a system for determining the best frequency will be established. Meaning in the first few steps of Planned Maintenance the focus will be on eliminating breakdowns but as the team matures on their journey, the higher steps/phases of Planned Maintenance focuses more on developing a robust strategy on how to maintain the equipment and achieve a Predictive Maintenance stage. This is where the different maintenance tasks such as Preventive Maintenance, Predictive Maintenance, Maintenance Prevention, Corrective Maintenance, Time-based Maintenance will be introduced and a decision diagram or algorithm will be developed to fully understand when these tasks are feasible to used. Similarly much like RCM. If zero breakdowns are really possible in the technical sense then the team cannot go and move forward on the higher phases of Planned Maintenance. What TPM is actually doing is not about eliminating the failure but rather prolonging the life or Mean Time Between Failure of the equipment.

Fourth breakdowns and failures may be easy for mechanical parts as most of this parts will wear out or deteriorate when it reached a given time or period but we cannot say the same for electronic parts. Failures of electronic parts and components are random in nature which means that it can fail at any given period. Electronic parts do not wear out, failures and breakdowns we encounter for electronics always happens when we least expect them most.

Fifth, a typical equipment can fail in a hundred ways or more. What maintenance can actually do is to understand every single failure so that we can adopt a feasible task before it happens. What maintenance can do is prolong or actually control the duration of failure

• Understand which failures can be prevented and apply Preventive Maintenance

• Understand which failures can be predicted and apply Predictive Maintenance

• Understand which failures have minimum consequences and just allow them to fail

• Understand which failures have high impact and consequences but cannot be prevented nor predicted so the last remaining option for the maintenance is to modify or redesign the system

I have nothing against TPM in fact I have lived, eat, breathe TPM when I was handling the pillars of Planned Maintenance, and Initial Flow Control Activities during my time with Amkor for 8 years so I definitely know what I am saying and there are no contradictions on what I am pointing at. Sometimes you need to experience TPM before really understanding it in the first place. There are many items I have experience that are not written in any TPM books. Let me give you an example, during my time handling the Planned Maintenance, our goal was to zero out all breakdowns and so I asked each of the 22 departments involved in our Planned Maintenance to provide me the breakdown data of their pilot equipment for the last 6 months to create a benchmark. One department, (let us call this as Department A) was providing a data for their pilot machine with an average of around 10 breakdowns a month, the other department, (let us call this as Department B) was giving a data of a consistent 1 breakdown a month. If I ask you which department is performing better, obviously you will answer Department B, since it is only experiencing 1 breakdown a month. If you answer Department B is the better department then this is where you are terribly wrong because that department belong to the Facilities/Utilities group and their machine undergoing the Planned Maintenance was a sub-station. Meaning a failure of one sub-station in a manufacturing plant can paralyzed the whole manufacturing plant.

But before even thinking about a strategy on totally zeroing out all the breakdowns, maintenance must understand precisely what will eventually constitute a breakdown in the first place and this is where I think industry will have their own definition of breakdowns. Let me give you this quiz as an example and kindly answer the following questions. (Answer to be revealed on our next newsletter)

1) A Function Loss Breakdown where machine totally stop