How to implement a SMED/quick changeover program
As many organizations begin their journeys toward a lean enterprise,
they are finding the road to be difficult and filled with obstacles. The
question that is most asked is where to begin.
While the market is increasingly demanding more customized products,
manufacturers are under constant pressure to reduce costs.
Non-fulfillment of orders more frequently results in losing business to
the competition. Combine these factors with the high cost of inventory
and the need to increase productivity, and it becomes obvious that
mastering quick changeover is essential to an organization’s survival.
As an organization begins a lean manufacturing implementation, its
ultimate goal is to produce according to customer demand (takt time)
while utilizing ”one piece flow.” For this to happen, machines need to
be set up more often, highlighting the need to reduce setup time.
Reducing setup time results in increased production, better quality
parts and a more flexible workplace.
Single-minute exchange of dies (SMED), similarly known as quick
changeover, like other lean tools, requires a committed effort from
within the organization. One of the major pitfalls organizations fall
into is the desire to rush into a changeover program with very little or
no upfront planning. With limited time and resources, the program is
doomed for failure. The other common mistake is failure to document and
standardize the process. Finally and most importantly, management must
demonstrate a full commitment to the program. If the changeover program
is not a high priority to management, then it will not be a priority to
anyone else.
Preparing for Analysis
As an
organization prepares for the program, it must first ask the question:
Why are we doing this? The obvious reason is always to reduce costs, but
cost reduction and improved profitability will come as a result of
inventory reduction, smaller batch sizes, increased plant capacity,
quicker response time to customers, and better use of employees. Goals
for each of these need to be set and reported to the entire
organization. This early preparation will greatly benefit a changeover
implementation. Also a critical step, the organization must determine
which area or process will be attacked first. Value stream mapping is an
effective technique for identifying bottlenecks and prioritizing areas
of improvement.
The next step is to form an implementation team. The composition of
the team is very important to its success. Determining factors should
include knowledge, interest, ability to work with others, and, of
course, enthusiasm. The team will have regular members that attend every
meeting and are directly involved with the changeover: setup
technicians, line mechanics, operators, supervisors, and manufacturing
and quality engineers. The other members will consist of representatives
from other departments within the organization. They will not have to
attend every meeting but will have a role to play, especially when their
areas are being addressed. Some examples (but not a comprehensive list)
of other areas to be represented include finance, human resources,
manufacturing, materials, purchasing and planning.
After the team is formed, each member needs to be trained in the
principles of SMED/quick changeover, basic problem solving, root cause
analysis and (often overlooked) proper procedures for conducting
meetings. A well-developed training program that includes interactive
exercises is beneficial for the team as it begins to meet regularly and
to analyze the changeover process.
When the daily meetings begin, ground rules need to be set. Every
meeting will have a leader and an agenda; tasks will be assigned and
minutes taken. Structured, well-run meetings will reduce the
implementation time and will increase participation and the quality of
ideas.
Analysis
The first step in the analysis
is to videotape every detail of the entire changeover process from
cleanup to setup. The only exceptions are normal breaks such as lunch.
It is important that the changeover being filmed is a normal changeover.
If anything abnormal occurs, the changeover needs to be refilmed.
(Note: A simple setup of a camcorder on a tripod is sufficient. You
won’t need to bring Steven Spielberg in on this one.)
The next step is to create a baseline of the process. Each detail of
the changeover process must be identified and listed. The video should
be reviewed several times until the team is sure that they have
identified and listed everything that takes place.
After every detail is documented, the team members will conduct a
brainstorming session in which each element on the list will be analyzed
and classified into one of four categories.
Eliminate: Is the step really necessary?
Externalize: Remember, the key is not so much reducing the total
amount of labor as reducing the length of time the line is down. One way
to reduce downtime is to externalize tasks to the maximum extent
possible.
“Externalization” means performing changeover tasks either before or
after the changeover, “externally” to the changeover time. One common
activity that takes place during changeover is that the operator will
collect the various change parts required. If this is done during the
changeover, it will extend changeover time. This is something that can
be done ahead of time so that all the required parts are available the
moment they are needed.
Simplify: Any elements that cannot be
eliminated or externalized need to be simplified where possible. This
will include the elimination of tools, use of slots and keyholes, quick
connectors, and the like. As part of simplification, all adjustments
must be made measurable. This may be done with digital position
indicators, scales or scribe marks. Gauges also may be used, but these
are “tools” and should be avoided wherever possible.
No Change:
Finally, there will be many elements for which no improvements are
possible. This is OK, but they need to be identified as such.
Periodically, they should be re-examined in case process changes, new
ideas or new technologies allow improvement.
Once each step has been classified, they then need to be prioritized.
A good method to follow is to classify each one as an A, B or C. “A”
items can be done immediately. “B” items require a bit more time to
implement for varying reasons. “C” items are the long-range items such
as new equipment.
This is the point at which some organizations end the process. When
organizations go this far and do not implement any of the ideas, they
are in essence adding a ninth waste to the eight wastes of
manufacturing. Instead of walking away with nothing more than
improvements on paper, the team should now develop an action plan with
each task assigned to team members with a due date. Status of every item
should be reported at each meeting.
The new process should then be documented and each operator trained.
The new procedure will become standard for that setup. The
SMED/changeover program should also have a standard operating procedure
(SOP) generated for the next event. As the organization improves each
setup after this, new members should be brought in and trained until
everyone in the organization has been trained in changeover process
improvement. Eventually, the organization will be become a true lean
enterprise where everyone routinely contributes to process improvements.
Though the high cost of downtime always justifies changeover
reduction, the process can be a very painful and daunting one. Many
times, companies have tried and failed to develop a successful
SMED/quick changeover program. Using the ideas and steps outlined in
this article will certainly improve the likelihood of success.
Reference: How to implement a SMED/quick changeover program, by http://www.reliableplant.com/Read/14965/smed-quick-changeover-program
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