Why Implement SMED (Single Minute Exchange of Die) If Changeovers Aren't Your Biggest Constraint?

Very often Lean manufacturing tools used in isolationSince company "X" values each minute of production
only serve to embrace a culture of local-optimizationtime at $500.00 we can further break this down:
(optimizing the parts rather than the whole.) In other36 Hours x 60 Minutes per Hour = 2160 minutes
words, you can optimize operation "C" to the pointmore production time each day
that it is running great, producing terrific numbers, and2160 Minutes more production time x $500.00 per
really looks fantastic, but if operation "D" is yourminute = $1,080,000.00 increased sales every day
constraint, all your efforts on operation "C" may notprovided their customers keep purchasing all
have much of an impact on your overall throughputcompany "X" can produce.
or profitability.If that's not an impressive ROI than nothing is!
If you have limited resources, and can only focusAnd...they are still improving.
your Kaizen efforts on one issue at a time, I'dNow, just for a minute, let's pretend that company
recommend you focus on operation "D" in the"X" can easily out-produce customer demand, or they
example above, until it has been resolved, or is noare just a one-shift operation. Where's the value
longer your biggest constraint.now?
Sometimes, however, you can spend some LeanWell, the truth is, the dollars won't add up the same
improvement time on non-constraint processes andway, but company "X" could still enjoy the following
realize very substantial, even incredible, andbenefits:
immediate bottom-line gains. SMED is one of the Lean* Increased capacity, (capacity they don't actually
tools that virtually always pays for itself many timesneed at the moment, but may as sales increase)
over. Allow me illustrate with a brief case study.* Might work a shorter workweek or reduce
SMED Case Study:overtime
A medical device manufacturer (company "X") can* Less downtime/production losses when an "urgent"
sell every product it can possibly produce. The morechangeover is needed
their lines run, the more money they make; it's* More maintenance attention to bottleneck
pretty much that simple. Changeovers take time, andequipment that runs 24/7 (if this situation exists)
therefore reduce the run-time of the lines. In reality,* Might not need to purchase additional equipment
however, changeovers are not their biggest(capacity increases negate need)
constraint when you look at the company as a* Might allocate freed changeover team time to
whole, (re-read your TOC materials on "Policyproactive maintenance of equipment
Constraints;") but opportunity for improvements and* Increased flexibility on the production floor (think
the potential for additional run-time was obvious.mixed-level-loading,) which results in smaller batch
To address line and product changeovers we formedsizes, and carrying less inventory, etc., and
a "kaizen team" and took a closer look at the* Could probably reduce a 1 ½ shift operation
situation in an "up-close and personal" way. I've listedto a 1 shift operation (that doesn't mean a RIF! but
some of the results from our efforts below. We'll letthat's a subject for another time)
the math speak for itself.Occasionally I'm asked, "Why should we care about
After a five-day SMED event, company "X" was ableSMED if we do all our die/mold changes at night
to reduce their setup/changeover time by 4 hourswhen nobody's here anyway?" The simple answer is;
per changeover. That may sound like a lot, or just ayou can do more of them in less time, with greater
little depending on your experience and industry, butease and safety, and prepare your company for
this is what 4 hours more production time means tofuture increased demand. You also need to ask; if
company "X."changeovers only take ten minutes to complete, why
Company "X" produces about 90 million units per yearwould you need a night shift to do them? Why
Every minute of line run-time is valued at $500.00 perwouldn't you just do them during the daytime so you
linecould run smaller batch sizes, and carry less
There are 9 lines runninginventory, while being more responsive to your
Each line experiences a changeover an average ofcustomer's needs?
once per dayI like to think of SMED as a tool of efficiency and
So, how does that all work out?execution. Great teams and great companies know
Well, a reduction of 4 hours of downtime due tohow to execute for outstanding results. Eventually,
changeovers for 9 lines actually turns out to be anmost companies will need to implement SMED in one
increase of production time across those 9 lines. Eachform or another. Even if changeovers/setups aren't
line literally has another 4 hours to produce pre-soldyour biggest "constraint" you may find that a little
products every day.attention in this area can have a major bottom-line
4 Hours x 9 Lines = 36 hours more production timeimpact for relatively little expense and effort.
everyday