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[ Back ] [ Eliminating ] [ Blocking ] [ Controlling ] |
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There are two key reasons that
simplifying products and processes is an essential part of mistake-proofing:
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There is a strong link
between the complexity of any task and the frequency of errors.
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The complexity of every
product and process can be reduced, often dramatically.
Simplification will generally
eliminate roughly half of the mistake-opportunities, while reducing product
development time and improving production efficiency. These changes can
often be achieved while improving product performance. |
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The figure to the left
demonstrates the link between defects per unit and the complexity.
Similar results over a wide range of product complexity have been
obtained at
other companies. Complexity is a function of the estimated total
assembly time (TAT) minus a constant (t0) times the
Total Number of Operations (TOP). |
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Although the slope of the
best fit line is virtually identical for these two companies, the
different relative position of the data reflects the relative quality
control performance. |
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We use a technique similar to
Design for Assembly methods to identify the opportunities for simplifying
products, and to evaluate the effectiveness of alternatives. A few examples of
the results that we have achieved using this method are illustrated below.
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This complex aerospace component was assembled in 1/7th
the time originally estimated by the production agency. Furthermore, the
first unit was virtually defect free. |
The original product had 3 castings, 35 welds, and
required extensive machining.
The new concept was a single casting and had only 6
welds. Using as-cast surfaces eliminated most machining. Wiring was
decreased from 26 feet to 12 inches. |
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The new purge valve has fewer parts,
simpler parts, and
no welds. As
a result the new design is easier
to fabricate and
assemble. |
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This original part was machined from rigid foam. The
assembly installs on the inner surface of a cone and was made in three
pieces so that it could be inserted past a rib. The fixture built to
hold the segments in place during bonding cost over $20,000
The new design was cast as a single piece at one tenth
the cost. Because the part is flexible, it fits past the rib without
having to be made in separate parts. The bonding fixture for this design
cost $200. Assembly time was also cut in half with the new design. |
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May we Help you Learn how
to simplify your designs?
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