Design for Manufacturability
Scott G. Gatherum.
Marriott School of Management
Brigham Young University
Outline of Presentation
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Design for Manufacturability Defined
How Can DFM Help Your Organization?
DFM Basics
A Practical Example of DFM
Summary
Reading List
Design for Manufacturability Defined
Manufacturability:
The elements of product and process design
that are combined and affect the needs of a
business and its factories.
DFM Defined Cont
“Design for Manufacturability means
taking stock of the tiniest component and
assembly steps in a product development
cycle–from the simplest fastener to the
overall material.”
Haung & Chen, The Journal of Technology Studies,
DFM Defined Cont.
Design for Manufacturing allows you to
improve efficiency by minimizing the number
of parts through part standardization and or
modular architecture so that the assembly is
cost effective and efficient.
How Can DFM Help Your
Organization?
Once you have a product design,
Can you Build it?
How Can DFM Help Your
Organization?
DFM contributes to the quality of your product by…
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Improving Reliability
Increasing Production Speed
Simplify Design
Reduce Necessary Inventory
Savings in the form of Costs, Time, Labor, and
Materials
DFM Basics
Consider the following when bringing a product
design to manufacturing.
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Customer Requirements
Process Reliability
Tolerances and
Repeatability
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Cost of Manufacturing,
Materials & their Availability
Technology
Customer Requirements
In order to meet the requirements of your
customers, you must first find out what they
want.
• Do they want something that is already on the market?
• Do they want more or less features?
Process Reliability
To improve process reliability it is important
to look at the relationship between the new
process and current process.
• Can any current process be used, and if not, how different
are they?
• Can we buy reliable technology to produce the new
product?
Tolerances and Repeatability
When manufacturing the product, any
variance must be minimized to ensure that
all tolerances are met.
• Will the equipment remain inside the designated
tolerances?
• Can the operators maintain the process with in the
designated tolerances?
Tolerances and Repeatability
• Are there appropriate reliability testing
parameters?
• Can the process be automated, mechanized, or
does it require manual labor?
• Will the equipment produce the same result each
time or does it require constant fine tuning?
Cost of Manufacturing, Materials &
their Availability
Economic shocks are not uncommon, to help
protect your manufacturing process
consider the materials cost and availability.
• What types of materials are needed and what are their
replacements?
• How much lead time is necessary and what is the
availability of the materials needed?
Cost of Manufacturing, Materials &
Their Availability
While designing a product it is vital to
determine the costs of manufacturing before
production begins.
• What labor is required for each process?
• What tools are needed?
• How quickly can equipment be purchased and/or repaired.
Advancement of Technology
Technology changes constantly. While
designing the process for production
consider the following:
• How reliable is the technology?
• Can it be bought of the shelf or does it need to be
customized?
• Can it be integrated with old or future technology?
A Practical Example of DFM
A boiler manufacture in the U.K. had developed a
boiler using a spring mounted fastening system.
During transportation of the boilers the screws that
held the spring clips would often loosen and fall
out. This forced the boiler manufacturer to
reconsider their whole product design and
manufacturing process to ensure the end result
was a defect free product and most importantly
that their customers would be happy.
Example Cont.
They started from the beginning. They first
considered what was necessary to meet the
customer needs. Second, they considered what
requirements the boiler had to ensure quality and
safety. Then they began to look at their resources.
The boiler manufacture found that their current
process of assembling the fasteners to the boiler
unit required a spring clip, nuts and a screw, which
held the sheet metal to form the outside casing of
of the boiler.
Example Cont.
The manufacturer began looking at the technology
that had been developed since they began
producing the boilers. A new technique had been
introduced that solved their problems. The new
fastener was a combination of a screw and
stamping. The new process involved a screw
punched into the assembly base material. The new
fastener sported a buttress type thread that was
designed to capture the outside edge of the
material.
Example Cont.
The screw is stamped directly into the base during
the fabrication. This new process eliminated the
old screws and clips that use to come loose during
transportation. The manufacturer then redesigned
the product to allow the screw to be stamped
during assembly. In doing so, the company
eliminated nuts, inserts, spring clips, and thread
forming screws. The company replaced all of
these parts for one helix screw.
Example Cont.
The end result reduced assembly time by about 15
seconds per part. At 10 parts per unit, for a total of
about 2.5 minutes per unit. This 2.5 minuets
results in an annual savings of $10,000. In
addition, the reduction of inventory and associated
handling costs were reduced 25-30%
Summary
When developing a DFM tool there are three
components needed to make the DFM productive.
• A complete understanding of the process design and the
interactions in the manufacturing process, and how they
both affect your overall output.
• A developed model that simplifies information into usable
segments.
• An early application of this information into the design
flow to allow these tools to make DFM decisions without
compromising accuracy, timing, or power calculations
Summary
Using the a Design for Manufacturability
program will eliminate parts and process
that simply make the overall process
cumbersome. Today, to keep or gain a
competitive edge, it is essential that
companies develop a DFM program before
the waste time, money and resources
producing inferior products.
Summary
Design for Manufacturability simply put:
• Improving Reliability
• Increasing Production Speed
• Simplify Design
• Reduce Necessary Inventory
• Savings in the form of Costs, Time, Labor, and
Materials
Reading List
Books
– Boothroyd, G., 1988, Dewhurst, P., Product
Design for Manufacture and Assembly
– Stoll, H.W., 1986, Design for Manufacture: An
Overview
Reading List
Journals
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iiE Solutions
The Journal of Technology Studies
Research in Engineering Design
Proceedings of the Institution for Mechanical
Engineers
– Professional Enigneering Publishing
Reading List
Web Sites
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www.designnews.com
www.elecdesign.com
www.dfma.com
www.machinedesign.com
http://solutions.iienet.org
www.tm.tue.nl/race/ce/dfma_2.html
Bibliography
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Haung and Chen., (2003), A senior Course in Design for Manufacturability.,
The Journal of Technology Studies
Jacquel and Salmon, (2000), Design for manufacturability: a feature-based
agent-driven approach. Proceedings of the Institution of Mechanical
Engineers. Vol 214 Part B, pg 865-879
La Trobe-Bateman and Wild., (2003), Design for Manufacturing: use of a
spreadsheet model., Research in Engineering Design, pg 107-117
Toupic, Laurie Ann., (2001),Design smart, for manufacturability.
www.desinnews.com, volume 12.17.01, pg 39-40
McClure, Robert., Design for Manufacturability, November 1999, iiE
Solutions, pg 41-44
Sulivan, Mike., (2001), One-Stop Product Development, Manufacturing, and
Marketing. Machine Design, August 9, 2001, pg 148