Stop Corrective Maintenance Repairs on Preventive Maintenance Work Orders.

Today's guest post by Blended Learning student Rick Clonan of Nissan is a sample of a communication to his organization to explain a problem that they had been facing. Interestingly enough it is a problem that many of us face in our sites. Thanks to Rick's willingness to share, you might be able to craft a similar example and share with your organization. 

There has been a lot of discussion as to why we are asking technicians to write corrective work orders for problems found on a PM instead of fixing the issue on the spot.  If we consider the example of the four machines below, it becomes clear why this is the case. 

        A technician is assigned a 2 hour PM for each of the machines below.  As he checks #1, there are no issues found and the PM is completed with no corrective work order generated.   As the inspection of #2 begins, he notices an issue.  This issue is not very critical and could wait until next  weekend.  He decides to fix it anyway.  The repair takes another 2 hours.  He moves on to machine #3.  There are no issues that demand immediate attention.  Since the PM of #2 and the corrective work order to fix the issue have taken a total of 4 hours, it is now time to go home, and the PM for  machine #4 does not get done. 

         The problem is, machine #4 has a failure in it that will shut the machine down in a day if not detected.  The next shift coming in has it’s own list of things to do and will not get to the PM on machine #4 that the previous shift did not complete.

    What we are trying to accomplish is to get as many failures detected as early on in the failure curve as possible.  It is understood that some repairs need to happen as soon as the fault is detected.   Most of the time this is not the case.  With the chance to plan for a repair, all of the parts can be ordered and the job will take less time.  We need to adapt to more of an inspection mindset when doing a PM and provide a clearly written corrective work order when a failure is detected.   This is not the way things have been done in the past.  We cannot continue to do things the same way and expect better results.  We must change the way we operate in order to improve. 




Great example! We hope this helps you with a topic to share or can be a model for a similar communication to your group as you chase after reliability.

Predictive Maintenance, Preventive Medicine and How Are You Feeling? Guest Post by Allen Canaday

Many procedures doctors are able to perform today are almost miraculous.  Science and technology have advanced at such a rapid pace over the last few decades.  Through integration of these new technologies with existing medical science, doctors are developing new procedures and medicines, when combined, allow for early intervention and even prevention of some diseases.  Culturally, preventive medicine has improved quality of life, provides greater longevity and lowers overall medical costs.
Much of the science and technology utilized in the medical profession has also found a home in the maintenance and reliability profession.  Today we have a myriad of proven technological tools available to diagnose asset health problems. Everything from ultrasonic and vibration to infrared and oil analysis,  these tools, when corrected applied, enable asset problems to be identified early on the failure curve, before the increasing costs of repair and potential catastrophic failure occurs.  Maintenance has evolved.  Maintenance is now the integration of science, technology, and training. 
Preventive medicine is firmly ingrained in our culture.  It works. Our confidence level is high and the experts tell us it is slowing the rate of costs increases for medical care.  It’s not uncommon to hear co-workers compare their “numbers”, it’s almost like a competition!  However, predictive maintenance is not nearly as culturally ingrained in the maintenance and reliability profession. Even though the science and technologies are proven many sites skip their appointment and miss the benefits. 
So why are the preventive/predictive technologies not advancing in maintenance and reliability profession at a more rapid pace?  Leave us your thoughts in the comments below.
Many companies can’t advance these technologies quickly enough while others continue to miss out on this competitive advantage.  If you are not utilizing the latest technologies in your facility start your business case now, before both yours’ and your assets’ health begin to diminish.
By the way, how have you been feeling?  It may be time for you and your maintenance strategies to have a check-up.  

Preventive Maintenance and Exercise: Three ways they are the same and one way they are different

Preventive Maintenance can be a lot like exercise but we will talk about just three of the ways they are the same and one major difference in today's post.
The three ways they are the same include the following:
Both of them can prolong the life of the asset. That asset may be a body or a machine but by doing the right activity at the right time it gives you the improved reliability that you need long term.
Both of them when done incorrectly will cause premature failure. If you go to the gym and start by lifting the wrong amount of weight or lift it in the wrong way you could pull a muscle, tear a ligament, or even worse. If you lubricate your equipment with the wrong grease or while the asset is idle you can also induce failures and unreliability. You need to understand what the machine needs in ever category from volumes, to clearances, to loads, to tolerances, to conditions. The best way to understand this is by completing a failure modes effects analysis to identify risk and then ensuring the right thing is done at the right time.
Both have to be targeted and planned. If you run off to the gym and only lift with you arms and never focus on your core and legs then you are destine to under perform if not suffer a complete breakdown. Everyone has seen the guy at the gym that does this. He stands like an ostrich with skinny legs and big arms. He looks like he could topple at any moment. The underling problem is  weakness in his core and legs which makes him prone to failure in real world situations. He needs a well balanced plan that includes all the major muscle groups. Without this plan he could possibly focus on the things he likes (the vanity muscles) and not the things he needs (the core). The same goes for the equipment in the facility. If you don't have a well defined equipment maintenance plan and the discipline to follow it you end up with equipment that is not serviced properly and unreliability makes its way into your area. Typically this will mean that only the easy task are done or only the task that are most obvious while the hard or cumbersome PM activities are either not identified or not completed at the right time.
So how are they Different?
They are different because you can skip one exercise in your routine but the one skipped PM step can send you to the bottom of the ocean. Exercises improve and preserve condition but PMs inspect and preserve condition. For example if you skip one visual inspection of a sealed connection and you miss the slight leak it could become a catastrophic blow out by the next scheduled date. So even though some days you might skip one step in your workout don't do the same to your PMs.

In the end you need to take care of your body like a well oiled machine and take care of your machines like a well trained athlete. Train hard but with a plan and follow the procedure to prevent failures. Use FMEAs to identify risk of failure and design your equipment maintenance plan to mitigate these risk. Build procedure that show what to do, how to do it, and when.  This will reduce the risk to you and the facility. Oh...and don't skip leg day in the PM world.  

Check the Pump: Same Step Different Results

Many of us have preventive maintenance task in our facilities that are made up of a noun, a verb and a few connector words. They look like these:

• Check the pump
• Check the valve
• Inspect the belts
• Clean and inspect

Do these look familiar? If they do then ask yourself  two questions. If you send your 20 year veteran mechanic and your 4 year technician out to do these task will you get the same results? And secondly, if you send your 10 year technician out twice over  a 3 year period will he or she do the same thing both times? The answer is probably not. This introduces variability into your equipment maintenance strategy and unreliability into your assets. So what can we do? Here is one examples of how we could very simply step up repeatability and effectiveness of your tasks.
Let's say you have a PM task that traditionally would have said "Inspect Hydraulic Hoses for Wear" You could get any number of different responses and levels of performance. Even if you add the levels of wear A through D you still leave room for interpretation. Whats the difference between mild and moderate? But if we add the descriptions in parenthesis then it removes quite a bit of the ambiguity. This become a much more effective and repeatable PM step. We can take it a step further if we are equipped to collect additional data. If you record instances of each on the asset you can improve the task even more to a quantitative level. This quantitative PM is the best indicator of asset health.
The key here is that PM task do not have to be long and full of loads of pictures to provide good results you just have to choose your words wisely.

Keeping Good Parts Good

When it comes to inventory availability, it’s important to have the right parts in like-new condition to best support maintenance operations. The standard used by many is the same method that the Original Equipment Manufacturers (OEM’s) and distributors use to store spare parts.
The location where some spare parts are stored is critical to meeting the “ready to use” requirement. Minimizing the effects of temperature and humidity is basic, but the protection of parts against the effects of handling during cycle counts and normal store room movements is also a contributor. When possible, it is favorable to have vendors keep the spare parts on their shelves and use a “Just In Time” delivery agreement for access. When not possible, precautions must be taken. Parts that are not in prime condition for use are just as detrimental as no parts at all.
Table 1 shows several types of parts kept in most warehouses or unit locations that need special attention and the category of environmental hazard for these parts.


Electrical Parts.
For many electrical parts, particularly parts with circuit boards, the three main environmental hazards that need to be guarded against are temperature, humidity and Electro Static Discharge (ESD).
During the last twenty years, the nature of electronics used in running a manufacturing plant has changed through the use of more advanced computer controlled equipment.  This equipment relies on the use of printed circuit boards that require a low humidity environment with little fluctuation in temperature.  Changes in temperature and humidity can cause the micro connections between the components and the printed circuit board to separate or warp.  These components are also subject to short circuits from small amounts of voltage, the source of which can be as small as a micro-discharge from the person holding the part.  For this reason, these electronic parts must be kept in their special ESD packages, usually a black bag made of non-conductive material originally supplied by the manufacturer.  These parts can be so sensitive that even when ESD parts are removed from their special package, the handling person should be grounded using a specially designed ground strap to avoid ESD damage.
Figure 1 is a picture of a typical electrical assembly properly packaged in an ESD bag and enclosed in a custom fit foam container. All employees should be alerted to “black-bag” parts and the caution required to keep them functional.

Belts and Hoses.
Belts and hoses are subject to degradation over time from the affects of UV light, heat, cold and humidity.  Unfortunately, there are no black or silver EDC bags to alert users of belts and few plants accurately date or rotate belts and hoses when aging occurs. Since many of the hoses and belts kept in a store room are an insurance spare, these parts may not have a high turnover.  When possible, it is best to allow the part supplier to keep these in their environmentally controlled warehouse.  This will ensure fresh parts are available for use when needed.  If not possible to keep the parts at the distributors’ warehouse, belts and hoses should be stored in an environment that is air conditioned in the summer and heated in the winter and not in direct sunlight. The store room should apply First In, First Out (FIFO) stocking practices so that the oldest parts are used first. In extreme cases, a lifecycle approach may recommend discarding and replacing dated belts and hoses after x number of years. We also recommends the use of flat storage wherever possible and hanging storage only with appropriate fully supportive fixtures.
Figure 2 shows properly stored gaskets.


Electric Motors.
Electric motors offer another possibility for degradation due to humidity, temperature extremes and vibration.  All motors should be kept in the same low humidity and stable temperature environment as belts and hoses, but they also require regular shaft turning to avoid low spots on the armature and coils and damage to the bearings from false Brinelling.  Motor turning can be managed through the use of tags attached to each motor that show the last turn date similar to the inspection date on a fire extinguisher.  Electric motors with horsepower greater than 25 should be kept heated through the use of electric heaters. This will prevent shrinkage and expansion from the effects of cold and heat on any metal parts that have different coefficients of shrinkage during temperature fluctuations.
Figure 3 displays an electric motor stored in a low humidity, heated and cooled warehouse.  Note the numbers on the motor used to align and indicate position on the shaft key way after rotation.  The date and position of rotation is also noted on the blue tag affixed to the motor.  The motor is bolted to a wooden skid to lessen area vibrations and ease movement

Summary.
It is important to recognize many of the parts kept in a maintenance store room can be subject to degradation and damage from the effects of the environment and improper handling or storage techniques.  Keeping unknown defective parts on the shelf for emergencies will compound a break down when the defective part is installed and subsequently removed/replaced because of improper storage.  Whenever possible, the use of the distributor’s stock should be used as this stock is turned over more frequently than the plants’ stores stock.  Typically, distributors and manufacturers are more likely to keep parts in their stores under tight environmental and handling controls.
If keeping parts on-site, keep them on-site correctly! Hidden damage is worse than known damage and will cost the site more in the log run.

Are You Doing PM Right: 5 Things to Keep You in Flight

So earlier this week I had the opportunity to fly the helicopter shown to the right in for its 100 hour Preventive Maintenance Inspection, which led to many of the thoughts in this post. Private or General  Aviation as it is known is really at about the same place as many of us on the reliability maturity scale. You might say they are "not quite best practice". Now for those of you that travel commercially don’t fret, that world tends to operate on a different level with a different mindset. While talking with the mechanic who was servicing the helicopter these points came to light. 
1. They could really remove a lot of non-value added step in the PM. Many of these have no discernible link to actual failure modes. Some of them looked more like an exercise by the vendor in selling parts and satisfying lawyers. As an aside someone should explain the basic tenets of RCM and the failure curves to lawyers so that they understand new does not equal reliable. Statistically, the most dangerous plane a private pilot can fly is one that just went through an overhaul and it is full of new bits.
2. If a skilled pilot or a skilled operator can perform the check then teach them and let them do these as part of a pre-flight or walk down inspection. This will lower maintenance cost and increase the organizations understanding and ability to identify failures early allowing for planning and scheduling of the repair work.
On the helicopter the rear drive pulley was worn and the damage was visible without tools or removal of guards but on the preflight checklist all it says is “check the pulley” and most pilots don’t know what the failure modes of the pulley are so they only check the most obvious and catastrophic. If a pilot noted the defect on the pulley during their inspection then the parts could have been ordered in advance and the ship would have been out of operation much less time and could have been  generating additional revenue and making the business more profitable.
3. Simply put, use Predictive Maintenance (PdM) technologies where you can to replace invasive Preventive Maintenance (PM) task that require downtime and can induce failures.
If you can check the equipment while it is running then you have less downtime and many times less maintenance cost not to mention you catch the failure much earlier allowing for the proper parts to be ordered and shipped in for your downtime windows.
4. PMs and check list should be quantifiable and repeatable. Each step should give tolerances or operating ranges that allow each operator or mechanic to do it the same way each time. One step in the Helicopter PM job plan ask the technician to use a screwdriver to pry against a valve and check for movement. This is quite ubiquitous. The mechanic and I both were left with questions like:
How big of a screwdriver? How much force should we apply? How much movement is acceptable?
In the end the mechanic shared with me that he does not follow the PM for that step because he has no idea what is “good”. He has opted for a different method that he was taught by others.
5. Lastly, If you see the phrase “As needed” or” As necessary” then you know you have a problem. Most of us do not know what these phrases mean therefor we need additional detail to be successful.
In the end, whether you are hanging on for dear life under a set of spinning blades or running a packaging line in a manufacturing facility you need to do great PMs to get great results and hopefully these suggestions might help you look at things in a new way.

How Long Does it Take to get from P to F on the Curve

The P-F interval (shown to the left) is sometimes taken as a graphic that shows how equipment fails and how long that failure will take. This is sometime called prognostics or remaining life. The truth of the matter is that it is really just a model of what one failure mode's failure probability looks like as it progresses down the path to functional failure.  The probability of failure goes up as you move down the curve. We can not plot out how long something can last once a defect is present. We simply do not have enough failure data on most common failure modes to accurately predict the time to point F or the point of functional failure. Our model is great for explanation of key concepts but fails to predict key points with anything more than probability. If we did have the number of failure data points for each failure mode then the down time collecting the data more than likely would have put us out of business or out of a job. Reliability Engineering is about eliminating and mitigating failures and by extension reducing the occurrence of data points.
Now their are exceptions where more is known about the individual failure modes and one example is some of the work the University of Tennessee is doing in the area of battery prognostics but, this is the exception not the rule.
Let me show you why we use the P-F model to make explanations not predictions. Let's take a bearing in a pump that was run with dirty oil. In that dirty oil was a particle of alumina or other hard substance. That particle is caught between the bearing element and the bearing race and a small dent or pit is created as the element tries to crush the hard impurity. Now our bearing has a defect that is not that different from a pot hole on the road over time it will grow.  When the elements roll over the pit the sides began to chip away these chips now contribute to additional impurities in the lube and the pit becomes larger the failure mode moves down the P-F curve in our model. Here is where chaos reigns. What if the load on the bearing increases and the elements presses on the spalling area with more force? What if an element catches a piece of the spalled out metal and skids creating additional heat and damage? What if the load decreases or the product being pumped changes? What if the filter that was bypassing is changed and suddenly the oil is cleaner? The point is all of these situations could change the time to point F. This is why we use the condition based maintenance (CBM) techniques to identify defects and start our planned replacement process not try to measure more frequently and "get all the good out of the bearing."
The point is that the P-F Curve is a great model for explaining why we do CBM and how it is different from traditional Preventive Maintenance and it is also very powerful for showing the link between the technologies and planning and scheduling but is not a timeline that can be used to "predict" when failure will take you down.
How do you use the P-F curve?

What I Learned from a Pharmaceutical Facility in Pennsylvania

This is a continuation of the "What I learned" series. 

Pharmaceuticals manufacturing is a very interesting business. For many years excess maintenance cost and maintenance down time has not been an area of prominent concern for many of these manufactures. But, with the need for additional capacity, the expiration of various block buster patents, and the rise of contract manufacturing their world is changing.
This facility was looking to be ahead of the curve and ensure they were ready for the changing environment. They wanted to be in charge of their destiny and not have it dictated to them.
The site showed me that there are many ways to succeed with reliability implementation and it can be called many different things.
This site used the energy behind the implementation of a new Enterprise Resource Planning (ERP) system and more specifically the Enterprise Asset Management (EAM) module as the framework for their reliability improvement efforts. As they implemented modules and sections they improved the processes and data that was required to be able to reach a new level of maintenance efficiency. This sounds like a logical choice but more often than not sites get over whelmed by this level of change all at once. Then the EAM implementation becomes simply a reimplementation of old practices, bad data, and ugly procedures in a shiny new software tool. It is a bit like adding a jet engine to a 1964 AMC Pacer. It sounds cool but it just does not end that well.
This site challenged the past standards and decided the old way was not good enough. They built a clear plan with managed subproject to prevent overloading of the organization.
They realized that the regulatory and product safety administrations were not there to put you out of business. Instead,  they are there to ensure you do what you said you were going to do. This site removed nonvalue added Preventive Maintenance (PM) task and refined procedures that once drove unreliability. They did all of this without increasing risk for the company or the customer. In fact, as they improved reliability with tools like Reliability Centered Maintenance (RCM) and Root Cause Analysis (RCA) in the later part of their ERP implementation they were able to provide more stable equipment and process which leads to a more quality product. Thanks to my time with this organization I know that when building a strategy for maintenance improvement it is very important to take a long hard look at the current state of the site, the culture, and the history of major initiatives and then prescribe an improvement plan that is specific to that site and it's culture.  As a consultant or a leader this means you can not always do it the same way you did your last project. You have to be constantly pushing the boundaries, matching the needs and using the culture to help them reach the goals they have set. This may change the title of your maintenance improvement initiative to a lean or Six Sigma project or it may be a part of an EAM or ERP implementation but in the end you use the site’s successful tools and momentum to drive the results that you need.

The Basics of Reliability Series: Preventive, Predictive, and Precision Maintenance

 

 

With the Triple P M single point lesson, you can cover multiple topics with two diagrams. There are two key points to be driven home with these graphics: first, a solely time-based maintenance strategy is destined to leave you missing the performance mark; and two, precision maintenance concepts and craft skills are imperative to effective maintenance. Other points can be added as the audience allows.

The first diagram shows the six failure curves from the many Reliability Centered Maintenance texts. When you realize that only 11 percent of the failure modes tend toward time-based presentation, you quickly see why a maintenance strategy solely based on time-based preventive maintenance activities is flawed. You also see that doing everything right with precision maintenance is crucial if you want to reduce the number of infant mortality failures.

The second graphic to devote to memory is the I-P-F curve, which shows that the most effective downtime prevention tool is to postpone the failure with precision maintenance and the second most important downtime preventer is to catch the defect early enough using predictive tools to plan and schedule the repair. One more point to make that ties into a later single point lesson on materials is that if you do not store it properly and maintain it in stores, then point S (the point it is put in stores), point I, and point P can become one and the same.

On this single point lesson, you can also talk about how, based on recent studies of PM maintenance tasks, the following holds true for the average facility:

·         30% of the PM tasks add no value.

·         30% of the PM tasks in the average facility could be more effective and efficient if they were done with PdM tools.

·         30% of the PM tasks should be reengineered to address the failure modes of the asset.

·         10% of the PM tasks are fine the way they are.

This sheds a bit of light on another substantial area of waste that can be removed with a plan and some patience.

More Preventive is Not Necessarily the Answer

More is not necessarily better when it comes to preventive maintenance you have to find the right amount done right with the right tools.

Lets first talk in extremes, there are some facilities that are truly reactive in nature and only fix equipment when it breaks. This keeps them very busy and leaves little time to do preventive (PM) or predictive (PdM) maintenance. This can lead them into a death spiral of unreliability. Many of these sites believe that if they could just get a bunch of PMs, then they will escape the spiral.

On the other side there are also other facilities that over time or in response to an incident have created a large portion of their backlog that consist of PM work and again they face many breakdowns and unreliability. If PMs are good why might these facilities experience an increase in breakdowns and unreliability?

One answer is infant mortality. In other words by doing more invasive PM inspections, such as opening a gear box to inspect the teeth, they actually induce failures. These failures can come from dirt and debris that accidentally gets into the box while it is open or improper reassembly upon completion. In this example many of the PdM tools could eliminate this PM activity in most cases and in turn eliminate the infant mortality issue entirely.

So the second enemy in more PMs is the possible loss of effectiveness because of low quality procedure, or poor execution in the field due to labor overload or has a lack of training on the added task. Many facilities ramp up the number of PMs by getting suggested PMs from vendors or coping other facilities PM procedure. This leads to task that don’t address the failure modes and in many case may not even address the equipment in question. 

So if you want to increase your level of preventive maintenance and your reliability take these steps:

1. Create a plan of what equipment and when. This could be based off of criticality.
2. Generate solid craftsman reviewed PM task that are failure mode based and detailed to the right level. You can base them off of example if they are reviewed and verified prior to deployment.
3. Finally use the predictive maintenance tools to eliminate the invasive preventive maintenance that plagues you by adding defects to your system.

Grow a good program a little at a time as apposed to a bad program overnight.