hi friends,

I want to learn about preventive maintenance basics. I want to improve my knowledge about preventive maintenance.

what must I do?

If you all help me I will be happy...

thanks for your help...

Quaresma:

I would forget preventive and concentrate on predictive maintenance. Time based preventive maintenance in most cases is not economical, missing failures that happen, or replace items on a time base system that will yield more life cycle time. Predictive surveys components allowing them to achieve maximum life cycles therefore saving money on parts and labor. Train, read, pratice, and begin all over again and again until sucess has arrived. Technical Ass. would be a good start in the training department.

quote:

I would forget preventive and concentrate on predictive maintenance

If you don't even master preventive, don't start with predictive.
Preventive maintenance starts with the basic concept: keep de machine clean and lubricated...

To jumpstart, learn the various curves of RCM:

http://www.reliabilityweb.com/excerpts/excerpts/rcm_chap4.htm

quote:

Originally posted by JB:
Quaresma:

I would forget preventive and concentrate on predictive maintenance. Time based preventive maintenance in most cases is not economical, missing failures that happen, or replace items on a time base system that will yield more life cycle time. Predictive surveys components
allowing them to achieve maximum life cycles therefore saving money on parts and labor. Train, read, pratice, and begin all over again and again until sucess has arrived. Technical Ass. would be a good start in the training department.

JB: PdM is useful and effective under certain conditions and is NOT a universal 'silver-bullet'. It is an important, but not an 'only' strategy. Age-based maintenance is useful under the right conditions and is the one to use for certain failure modes. For certain failure modes, a run-to-failure will be the right approach. And for some others 'failure-finding' is appropriate.

I am all in favor of PdM, but only for those failure modes where it is appropriate.

V.Narayan.

Q: Knowing and understanding the PM program function is critical. PM programs of today are not what they used to be especially since the advent of Reliability Centered or Reliability Based Maintenance. They are the basis for any good program.

A good rule to follow is to perform a Simplified Failure Modes, Effects and Criticality Analysis. Then from that do Maintenance Plan Analysis. Here you list the critical system and its children (lowest maintainable component level, pump, motor, etc.) From this you can determine the best methods to apply to your equipment. Be it an inspection PM, a PM that performs PdM data collection and analysis or simply cleaning and inspection of the equipment.

This provides you with some orderly method to
make the determination of what to do and when to do it. Of course there are issues such as schedule compliance to consider.

PM is fairly easy to schedule if you know the operating conditions.

Imagine you have a plant with 100 pumps/compressors etc.. running 24x7

You have to budget for the next year.
What spare parts will be used, what is the amount of lubricant, how many times?
How many hours you need to allocate?

Lets say we will do only predictive maintenance, do you realy think that you can tell management a year ahead how much money they have to allocate to keep the show running?

Scheduling is easy. Scheduling compliance is something else.

Say you have a monthly PM to lube a bearing. One month you get it done early on. Next month it is late in the cycle. The following month it is early again.

What you have just done is to underlube it then over lube it.

Keeping the PM execution within +/- 5% of scheduling period then becomes more important.

Keep in mind this is just an example and that each PM needs to be evaluated based on what it is supposed to do for you.

Dear svanels,

May I suggest that ease of scheduling and budgeting, while convenient, are not the reasons we should do PM or age-based maintenance.

The task must match the failure mechanism and consequences; that is essential. If the failure is hidden and has a safety or production consequence, a failure-finding task is necessary. If the failure has minor or trivial consequences, a run-to-failure strategy is justified. When it is well correlated to age, such as brake-pad wear or gas turbine blade fatigue (i.e., peaky shape in a probability density curve), age based maintenance is appropriate. When the physical degradation can be measured,and takes a few weeks or months from onset to functional failure and is reasonably consistent (following the P-F curve), PdM is appropriate. When there are high consequences and no effective task can be found, redesign is the only option available. This is RCM logic in one paragraph, and it works every time.

As Mr.Hatfield says, schedule compliance is important. I use a broader band-widths than 5%, but that is a matter of detail.

V.Narayan.

They way I see it is to keep it as simple as possible. We talk preventive maintenance and people think a strict schedule to perform maintenance. How can you be preventive in a cost effective way without analysing failures and using this as a starting point?

My opinion is that you only become truly preventive after a failure has been analysed and the cause checked at a fixed interval.

Predictive maintenance is much the same way. History is an important part of predictive maintenance. I would look at patterns on failures and try to schedule a planned job of replacement before the failure occurs. The use of technical professionals is also excellent to predict a failure with vibration or infra red.

Am I on the right track here?

Regards,

Ajay: Your are right.
Equipment histories are very important.

What I do is to categorize or rank equipment in order of importance, taking into account numerous factors, at the child asset level, which is the lowest maintainable component. I then start a Simplified Failure Modes Analysis which looks at Severity, Occurance, and current Detectability. I then do a simplified RCM analysis to determine if PM, PdM, Redesign or Run to Failure is appropriate. I then go back and look at what technologies might be used to decrease the occurance and improve detectability. I then at the business case for that technology.
The PM and PdM categories are then looked at in an Maintenance Plan Analysis. The MPA also calculates the total man-hours required to execute the PM program by labor type. From that SOP's are written.

This process is not as complicated as it seems and there are tools used to accomplish the tasks.

Usually I find that the equipment histories and failure reporting systems are lacking so the first cut is usually a SWAG, but it gets you started towards something meaningful. Eventually you can get it all under control.

As I tell clients " We are in a data rich environment and the proof is in the details of the data. We must collect the right data to analyze to affect the bottom line in a positive manner."

hi, friends....
thanks for all your replays..but now new question is coming...what about TPM (Total Productive Maintenance)?..

have a good work...

Not that I have something against PdM, in fact I am a strong fan, but Ajay made a very good point about history. To do analysis you need data, the more accurate the data, the beter your predictions.
PdM is not a substitute for PM, they are both complementary.

Now we call it RCM, when I started years ago as young maintenance engineer, we didn't knew the term RCM, but we were doing it.
When a new equipment was coming in, we first analysed its working environment. A swamp drilling rig were you had only a half day for maintenance between drilling wells, received another focus as a shop compressor. The impact of not having that piece equipment available, was the basis for allocation of resources (manpower, parts, standby services etc.).

TPM. Now that is an interesting subject. How many organisations are willing to employ highly skilled technical people to operate a production line e.g. bottling, packaging, etc. I really cannot see TPM working in a company that specialises in FMCG.
Total Productive Maintenance TPM, sounds really good for a production specialist but not an engineer. If you have the advantage of having technical people operating equipment on a packaging line, with knowledge and experience of trade then I would suggest TPM.

Our operators are not very technical and I will definately not use it in our facility. I still believe in RCM at the applicable stages for the relevant equipment.

Has anyone heard of BCM???
Business centered maintenance.
Any opinions on BCM?

What TPM's scope are you considering? Is it by JIPM or something similar to the attached version below:

[URL=Posts About Improving Reliability : From TPM to RCM]

http://www.reliabilityweb.com/art05/tpm.htm

From the above article, it appears that TPM is an asset management imporvement program. The scope is good to see the big picture and to learn by zooming in each area. The principles seem applicable anywhere.

Wow, forget dinner and a movie, just straight to the hotel!

Get the basics down first, before going nuts with all the more advanced tools like RCM. You know, a little maintenance foreplay:

1. Determine what assets you have;
2. Figure out if you have a history, and what that history is;
3. Start figuring out what your critical equipment is: safety/regulatory; production; and cost impact;
4. Greasing, lubrication, alignment, cleaning, etc. - need to get a handle on these issues first;
5. Determine scheduling and personnel capabilities;
6. Training, where necessary, with a focus on safe work practices;
7. Learn about your vendors and how they are helping/hindering you;
8. Once you start getting a handle on these areas, now start looking to which advanced maintenance tools will assist you.

Otherwise, jump in with both feet and drown (or get kicked out of the room).

Howard

Howard your list can be considered as the 8 Commandments for implementing a CMMS
Unfortunately not to much people obey them (just like the 10) that is why we have these maintenance horror stories.

TPM will work if Operations take ownership of his equipment.

Don't confuse ownership with " maintenance, you cannot work on the equipment because we need to produce! Maybe next week!! " (when the plant is down)

Since the very first sentance of this post started with "I want to learn about preventive maintenenace BASICS", I think Howard hit the nail on the head. If you don't get the basics down first, you're not only going to drown, but you also are missing the low hanging fruit. V. Narayan had a post on March 5, 2005 that included the following statement: "If we take care of basics, i.e. keeping equipment clean, dry and lubricated, we get 70% of the benefits". 70% - that fruit's hanging so low that you have to take care not to step on it.

Hans,

Thanks, Hans but I have to make a correction to the original statement (cant recall making it though). The basics include the following
- keep the equipment clean (especially guideways, sliding surfaces, inspection windows etc.)
- keep all the exposed part dry, also the lub oil
- use the right quantity and quality of lub, AT the RIGHT time
- keep the equipment and its component parts in alignment
- keep bolts and other fastenings tight; use the correct torque values
- keep machinery balanced (especially high speed rotating eqpt.)

If we do all this correctly, we will get rid of most of our machinery problems. Those who use TPM may recognize the above as TPM activities.

We still have an important volume of failures left to tackle after we do all this, but at least we can work on a smaller volume. That will help us focus better.

V.Narayan.

Vee, the title of the post you made on March 5 of this year was "Focus areas for RAMC". It can be found in the section called "Posts About Improving Reliabilty". Your comment about keeping equipment clean, dry and lubricated was only one part of your whole comment. I just thought it was applicable to this discussion.