Design for Manufacturability Scott G. Gatherum. Marriott School of Management Brigham Young University
Outline of Presentation • 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… • Improving Reliability • Increasing Production Speed • Simplify Design • Reduce Necessary Inventory • Savings in the form of Costs, Time, Labor, and Materials
DFM Basics • Customer Requirements • Process Reliability • Tolerances and Repeatability • Cost of Manufacturing, Materials & their Availability • Technology Consider the following when bringing a product design to manufacturing.
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 • 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 • 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 • 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