Running SLOWER to run BETTER - OEE paradigm shift

Maybe we have all seen it, the production line that is business critical and as such it gets a ton of attention. Let's think about this line as we know it - it runs OK - not awful, but we all know it can do better. We have started using OEE to help us assess our lines - and on this line our indicator for Quality is OK - not outstanding - maybe 95%. Our Availability numbers are also OK - averaging around 90%. Our Performance indicator too, seems OK at 90%. These factors result in an overall OEE of about 77%. In many cases - at 77% - many of us would be pretty happy - especially if we got to 77% from a much lower starting point; but in this case - this line seems to be pretty consistently performing in this range and we all see it has great potential to do better.

Remember, this line gets lots of attention - so with Performance and Availability both at 90% and lower than our Quality performance - we have a tendency to start with production rate. We push rate and find Quality drops AND Availability drops. A good question here might be: Are we actually running over "suggested rate" or "rated speeds" somewhere? As it turns out, in MY memory, we are not running over speed, but looking at that possibility helps us find some other issues. (More on that later.)

Let me give you a bit more information about the line in my memory - it is a confections line - relatively high speed - making a moulded product with great consistency - leveraging multiple wrappers arranged in a "parallel" array to spread the output of the moulding equipment over the array - with some overflow capacity via a "spare" wrapper - and then merging those multiple wrapped and trayed streams into a single line for casing and palletization. Sounds pretty ideal right - well it was. Only issue I can recall was it was a bit older - probably 15-20 years old - with some parts much older - but it ran well and pretty reliably. (I have also seen this scenario on a line for frozen breakfast food, a line for soft-drinks, a line for packaging deli meat - like I said - maybe we have all seen one or more lines like this in our careers.)

So - we push rate - and our indicators for Quality and Availability drop - we see an increase in mis-wrapped bars, we see more jams in the wrappers, and we see more stoppages and adjustments required as a result of the jams. So, perhaps counter-intuitively, we slow the speed settings on the wrappers down just a bit and..."Voila" - our outputs of good bars start to increase - we are at 98% for Quality - 93% for Availability and 87% for Performance - an Overall OEE of 79% - and perhaps we are on to something. Still we know Quality can be better so still room for improvement.

I would say - often a great first step - as you begin to centerline your lines and you look to use OEE to drive performance - is to "run SLOWER to run BETTER". Also, experience and best practice would suggest to start with your Quality indicator - there is so much to be learned there in terms of eliminating waste. "Begin with the End in mind." In our case, the rework caused when "pushing" rate was obvious - and we should have started with Quality - but we always believed we could run faster, get more overall output. Eventually, we did - but by shifting the focus to Quality - not rate - and on finding the "sweet spot" for all the elements of the line to reach improved Performance outputs and OEE.

Now, we can't end there; this is where we get into more about investigating our running rates - no one should be content to slow down - especially at some level below a manufacturer's rated speed - and on a line that is business critical. So what next...?

As I mentioned - this line is business critical, it runs a long standing consumer favorite and popular bar - and has done for years. The products this line runs are so popular that running Saturdays and Sundays isn't unusual. We all know the strain that running 6 and 7 days can place on a line - the reduction in Preventive Maintenance, the wear and tear on personnel and equipment. What we find out is perhaps not shocking - as we investigate and we focus on the wrappers - they are complex, relatively high speed machines and they are also a bit older (perhaps I should say "experienced") and have been "work horses" for the company - we uncover that our wrappers have been the sight of "benign neglect" - benign neglect is:

• The reduction of frequency of PM's - to get more run time.
• The use of non-OEM spares and whatever is available - to get back up and running in the interest of more run time or lower costs.
• Trimming the budget, going low-cost, on the "core" lines to fund new items.
• The myriad of well-intended, "pro-business" practices and excuses to try to do "more with less" while we "squeeze" and "sweat" assets.

I am a firm believer in assuring production assets are as fully utilized as possible - but I would suggest that assets that are maintained well will perform and "sweat" for longer; running the marathon and paying back through years of consistent, reliable performance vs. short sprints punctuated by high cost equipment maintenance or parts/systems failures. A short term departure from good maintenance practice can be overcome with a strict return to proper PM practices - but, a pro-longed departure - will ALWAYS have impact on Availability.

The practice of benign neglect can cause drift from "standard condition"; the condition the machine was intended to perform with; prior to field modifications, non-OEM part substitution and the wear and tear of long runs with less than required preventive maintenance and operator care. "Standard Condition" should be what our PM programs are designed to maintain, with appropriate frequency to support product Quality and Performance. Bottom line - benign neglect is not benign.

Let's remember - when we centerline - we have to ensure that our equipment is in "standard condition" - so I would always recommend an overhaul of the equipment - in conjunction with the OEM suppliers whenever possible - and restoration of parts to OEM equivalents "or better" (not "or cheaper"); to determine the current "standard condition" prior to starting a centerline exercise. A strong review of Quality measures is another critical pre-cursor to centerlining to assure that the process "begins with the end in mind" and targets the perfect product from the customer or consumer point of view.

Ultimately, as we restored the wrappers to "standard condition" and sharpened our focus on Quality - we were able to drive further increases in overall OEE - by fiercely protecting our PM regimen to preserve "standard condition" - allowing us to eventually increase rate (Performance) AND maintain very high levels of Availability.

I would love to hear your reactions and experiences - please comment and share. Feel free to reach out to me directly at [email protected]. In my next article, I plan to describe to issues leading to the "Vicious Circle" that leads to performance declines and employee frustration - and how they can be overcome with a commitment to behaviors in the "Virtuous Circle" of performance improvement.