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How to Reduce Reactive Maintenance

  • 1.  How to Reduce Reactive Maintenance

    Posted 09-28-2009 18:55
    I am looking for your thoughts, experiences, and technique for reducing reactive maintenance. Please include a definition; plus "what is an acceptable amount (percentage)" each week. I am understanding that reactive maintenance is more costly than proactive. If so, what advice would you give a client asking this question.


  • 2.  RE: How to Reduce Reactive Maintenance

    Posted 09-29-2009 13:17
    John, A good place to start is to examine the failed components and generate probing cause provoking questions. The machine wants to tell on itself...listen (look at) to the evidence.


  • 3.  RE: How to Reduce Reactive Maintenance

    Posted 09-29-2009 15:04
    thanks Dabbler. your answer is from practical standpoint and makes sense. but if you could, answer this question from a CMMS database standpoint, where there are thousands of assets, decades of history, and .... all of your senioe maintenance staff retired in the last 6 months (leaving you with junior staff).


  • 4.  RE: How to Reduce Reactive Maintenance

    Posted 09-30-2009 05:02
    John, Begin with defining conventions such as meaning of work order descriptive terms such as "overhaul", "rebuild", "replace", "repair", "restore", "refurbish", etc. so they cleanly mean the same thing to all. Also, select and build a failure modes table that is meaningful and specific and insist on its use when closing work orders. With thoughtful front end preparation users will surrender what they know and what they discover/learn during the work. It won't take long to identify tends/gaps/poor practices/training opportunities.


  • 5.  RE: How to Reduce Reactive Maintenance

    Posted 10-11-2009 22:02
    Hi John, if I read this right, you are ;
    1. Experiencing the dreaded exodus of knowledge coupled with
    2. Long standing high reactive maintenance levels.
    In one way this actually puts you in a "better" position; changing the culture of an entrenched maintenance team is much harder than doing it with new guys. I think this is what you are alluding to by your question, it sounds like you sniff the opportunity for change?

    I think to start you need to ask a few more fundamental questions if you haven't already. Things like :
    1. How will changing this culture improve your plant operation - just aiming for a simple benchmark of reactive vs PM will not guarantee improved plant performance (assuming that performance is defined - cost/unit, raw output etc). Measuring where you are is essential, and it has to be linked to plant performance otherwise it is just a number in isolation.
    2. Are upper management keen to assist (or at least not hinder you) They will generally not jump at helping you as this type of exercise can cost a lot of $$ if new systems and training are involved - unless they are exceptionally forward thinking management.
    3. As the other poster has touched on, the data can hide the answer for many issues. Your challenge will be making sense of years of mixed data. Not having your long termers with you means you have to try and sort the data into useable forms on your own (or getting some outside help would be advisable).

    Perhaps some forum gurus could offer some timely advice ?


  • 6.  RE: How to Reduce Reactive Maintenance

    Posted 10-11-2009 22:19
    thanks Damo for your response.
    Can you provide a definition of reactive maintenance.
    Changing culture will be an issue, ey, but to make this question easier, lets pretend it is not an issue. Also, lets assume the data is fairly good, ie failure/problem/cause coding. Otherwise we won't get off the dime on this conversation.
    So to restate,.... how would one go about reducing reactive maintenance?


  • 7.  RE: How to Reduce Reactive Maintenance

    Posted 10-11-2009 23:27
    John, definitions abound, essentially they all relate to "an unscheduled maintenance activity in response to system or equipment failure". I expect there are variations, including the level of planning, and the definition of "failure".

    So ignoring the issues of culture change and data interpretation (brave man), personally I would go about it in 2 ways :

    1. Just start by doing more of the opposite - that is planned maintenance activities. Depending on your plant type and industry, quantity of rotating equipment etc, you will need to assess the right balance of condition monitoring / periodic replacement / planned shuts etc. It doesn't fundamentally assure a corresponding reduction in reactive mtce, but it will by it's action improve understanding and ownership of plant condition; and

    2. Go after the main contributors to reactive maintenance activities. Look at top 10 equipment failures or whatever number is appropriate, pareto analysis of failures / downtime by equipment number etc will tell you where the bulk of your problems are. Getting on top of these will be important to giving you breathing space to start adding some finesse to your planned activities. It will also possibly provide you with some quick wins to give you some clout with managers (who control your budget).

    There are probably many other aspects to it, and I should state up front that this type of work(turning around reactive plants) is not my immediate area of expertise (which is in fact reliability/capacity modelling). I have an interest in all things maintenance however, as it pertains to my understanding of what I am trying to model. Which is why I hope for your sake the "old timers" out there can expand on my input as needed.

    Regards
    Damien.


  • 8.  RE: How to Reduce Reactive Maintenance

    Posted 10-14-2009 02:39
    John,
    quote:
    I am looking for your thoughts, experiences, and technique for reducing reactive maintenance. Please include a definition; plus "what is an acceptable amount (percentage)" each week. I am understanding that reactive maintenance is more costly than proactive. If so, what advice would you give a client asking this question.

    Permit me to start with some basics. A machine can be in two states, working or not working. If it is not working, it may be it is because we have decided not to use it, i.e., it is on standby or under repair. Or it is possible the machine has failed without our knowledge of when it would do so. The work we do to such a failed machine is reactive.
    So it our lack of knowledge of time of failure that is relevant to your question. The solution then becomes obvious. What can do to gain such knowledge?
    1. Failures may be age-related, and this is true of about 10-20% of all failures. The mechanisms that lead to age-related failures include e.g., wear, corrosion, fatigue, fouling etc. Usually, when the product is in active contact with a component, fouling, corrosion or erosion is likely. If parts in contact move relative to each other under load, wear is likely etc. For age-related failures, age-based maintenance is applicable - enter Preventive or Time Based maintenance. What 'knowledge 'do we need? Historical data of past 'run lengths' is the information we need, e.g. how long does it take for a new filter or heat exchanger to get fouled? Age related failures tend to have consistent 'lives'.
    2. The vast majority of failures are non age-related, ca 80-90%. Such failures are often called 'random' though that is not strictly correct. The main idea is to predict a forthcoming failure. We detect the onset of failure and the rate of degradation. This is Condition Based or Predictive Maintenance (CBM or PdM). Typically, we track vibration, noise, temperature, oil quality etc. This is a powerful source of knowledge.
    3. There is a class of failures which are 'hidden'. In these cases, we do not know whether the item is in a working or failed state. Examples - Relief Valves, Standby pumps (will they start on demand?), Emergency generators etc. Here we have to 'detect' the failed state in time. For this we need to test them at the right time. To do that we need their MTBF data.
    A long answer to a short question, sorry.


  • 9.  RE: How to Reduce Reactive Maintenance

    Posted 10-14-2009 08:20
    I’d like to add a few concepts which I’ve come to understand over time.

    I believe a portion of Vee’s age related failure definition actually fits usage related failures better. My understanding of true age related failures include equipment that has a constant wear mechanism which exhibits itself over time.

    Examples include oil which may loose important additive properties over time and equipment which operates in constant corrosive conditions; in other words, the wear mechanism is constant and time is the variable.

    The economic slow down has demonstrated that time based PMs are not optimal for most equipment in which usage is the wear mechanism. We found ourselves manually adjusting PM calendar frequencies to match our economically induced lower run rates. By switching to usage based PMs and PI Historian based usage tracking, the PMs are able to adjust themselves to our run rates.

    Since most of our PMs are truly usage related but are activated by the calendar, the ones which we haven’t converted will need to readjust when our run rates increase.


    As for work type percentages, I don’t think there is a single percentage breakdown you can use. For instance, your RTF system will be nearly 100% reactive by design. For critical systems, PM would hopefully be higher, but since many failures are random in nature, CMs will be inherent.

    Many systems are PMed using older maintenance techniques which RCM has demonstrated to actually be a failure mode in itself. Leaving an operating system intact is in many cases your best option.


  • 10.  RE: How to Reduce Reactive Maintenance

    Posted 10-14-2009 08:46
    Thanks for everyone’s feedback so far. I am always looking to learn and improve my skills & knowledge.

    I would like to re-phrase my question however on (how best) to reduce reactive maintenance.
    In particular I want to make use of the existing CMMS/EAM product as to data reviews, analytical reports, and trending technique to help the user site become more proactive.
    I also believe there are many definitions for “reactive maintenance”.
    Right or wrong, this is mine: any repair work done outside of the weekly schedule.
    Emergency work is done right away – and therefore is reactive. Urgent work may also be labeled as reactive.
    But if a normal repair job is identified in advance, completely planned, and scheduled in advance, then I do not believe this is reactive maintenance. I don’t care if it was identified by PdM or CBM or PM inspection/walkdown. My experiences tell me that when work is planned/scheduled in advance it is safer for the work force, more efficient for them, and aides in overall crew/craft coordination. Conversely a reactive job has staff running around, making errors, potentially wasting time, and, often expediting materials (all of which adds cost).

    Final notes:
    (1) there are more CMMS client sites at the low end of the spectrum that have small engineering staffs and maybe do no planning or failure analysis. They may also be a predominantly reactive maintenance shop. This is the audience I am targeting. So how do we help them?
    (2) there are several data reviews any CMMS organization should be performing on a regular basis (to help them assess trends, problems, and data). And this………… is what I am looking for…as well as any other related thoughts.

    >>> looking forward to this on-going dialog

    w/br
    j.r.


  • 11.  RE: How to Reduce Reactive Maintenance

    Posted 10-14-2009 09:38
    quote:
    Look at top 10 equipment failures or whatever number is appropriate, pareto analysis of failures / downtime by equipment number etc will tell you where the bulk of your problems are. Getting on top of these will be important to giving you breathing space to start adding some finesse to your planned activities. It will also possibly provide you with some quick wins to give you some clout with managers (who control your budget).


    Having re-read Damiens response (below) I did think he was closest to where I want to end up.
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Look at top 10 equipment failures or whatever number is appropriate, pareto analysis of failures / downtime by equipment number etc will tell you where the bulk of your problems are. Getting on top of these will be important to giving you breathing space to start adding some finesse to your planned activities. It will also possibly provide you with some quick wins to give you some clout with managers (who control your budget).
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


  • 12.  RE: How to Reduce Reactive Maintenance

    Posted 10-15-2009 02:32
    John,
    The term preventive maintenance (PM) is a legacy from the 1950's Manufacturing Industry, particularly the automobile plants. The concept was to 'prevent' failures through a hard-time task, replacing a susceptible component well before it failed and stopped a whole production line. This alone was considered pro-active.
    Then PdM came along, allowing us to predict time-to-fail for these susceptible components. That allowed us to plan and schedule the replacement, addiing to our list of pro-active tasks.
    In the 70's and 80's, RCM influenced our thinking. We could allow items with a low failure consequence to run-to-failure. Such breakdowns are anticipated, because we have decided to let the items fail, so they can be planned, i.e. work steps, resources, spares, logistics etc. identified. But we do not know when exactly they will fail, and hence they cannot be scheduled. In such cases, the planning can be pro-active, but the scheduling is always reactive. In addition, there are breakdowns that we did not anticipate, so there is no plan or schedule, thus reactive on both counts. Since in many Companies, for both types of breakdowns, no plan or schedule exists, your position that any activity not in the weekly schedule is reactive can be supported. For those Companies that do do plan run-to-failure tasks, most of the benefits of pro-active work are there, but there is some loss due to rescheduling the weekly workload. In practice, it is hard to make this distinction from a CMMS, so your concept of treating all unscheduled activities as reactive is justified.
    The problem has always been the term PM, meaning time-based maintenance. It is true that PM is pro-active, but so is PdM, and in theory, some run-to-failures too, because that is what WE decided to do, not what the machine decided to do (refer my earlier post).
    All work that we decided to do in advance and planned are pro-active, the rest is reactive. Ron Moore in his book "Making Common Sense..." provides data to suggest that the best performers limit reactive work to 10%. That is a good target, IMHO.


  • 13.  RE: How to Reduce Reactive Maintenance

    Posted 10-15-2009 06:01
    We look at top items from a few different perspectives.
    Top items by downtime - using level 2 system to record all process downtimes - this is the top items that break the process

    Top items by number of maintenance hours charged - review of all reactive work orders - look where guys are spending their time - this is where the reactive work is concentrated

    Top items by number of calls - review of all reactive work orders - this is the where the small items that continually break your schedule and annoy you are typically found - focusing on these drops the number of times you have to drop your tools and go check something out again

    Top items by total maintenance costs - review of all work orders - never want to forget the big picture and combine this with the downtime picture

    Strategy to protect schedule - establishment of reaction team and strategy. all calls go to small group (rotating shift maintenance team) to be handled, the remaining resources (day maintenance teams) are focused on scheduled work and they are protected by the smaller team.

    Next, the strategy turns to how much scheduled work can the reaction team execute.

    In addition, the reactive work performed by day maintenance crews (does not come from calls) originates from pm and pdm inspections... and other random failures occurring inside the scheduling window. Therefore, this data is collected and viewed in frames similiar to those described above.

    All data is reviewed by focused teams.
    Monthly corrective actions to prevent are just scheduled and executed. Larger initiatives and annual goals are established through a series of meetings and analysis where everyone has input and the priorities are agreed upon. This is the driver for the next round of improvements.

    sorry for the quick short & dirty answers... I typically just read and respond to these items on quick breaks


  • 14.  RE: How to Reduce Reactive Maintenance

    Posted 10-15-2009 06:18
    Vee - as always I appreciate your input.
    Seigga813 - I think you are very close to where I want to end up. There are many techniques that can be used for reducing reactive maintenance. It sounds like you have a scheduling process that includes repair work (as well as PM/PdM). And it sounds like you have different teams working different types of urgencies (fix-it-now versus routine repair).In any case I made note of the data analysis techniques you mentioned. bt.w. -- is this a weekly schedule? Thanks.

    >> to the audience, please note, I am still after "data reviews".


  • 15.  RE: How to Reduce Reactive Maintenance

    Posted 10-15-2009 15:22
    Yes - we work with a weekly schedule. The data is reviewed monthly and over longer periods for trending and analysis.
    Steven


  • 16.  RE: How to Reduce Reactive Maintenance

    Posted 10-30-2009 04:17
    JR, it sounds like you servicing customers in industries where reactive maintenance is high and where data review is helpful.

    CMMS can provide data and also productivity from better planning & scheduling to manage their maintenance performance KPIs.


  • 17.  RE: How to Reduce Reactive Maintenance

    Posted 11-01-2010 22:57
    A good maintenance program and a dedicated team will answer to that.