Mechanical Engineering | Design for Assembly (DFA)
The reality of being an industrial design company is that during our design consultancy we not only focus on the products design but also the products design and development and how its brought to life. The engineering design not only focuses on how pretty the products final look is but also the manufacturability i.e. the we need to design for manufacturing so that the product not only looks pretty but that it can be produced as well. That is why we engineer the products while we design them and make sure we work parametric and in parallel. At the end of the day, anyone can create a product that looks pretty but is it truly manufacturable? Some instance, being a little off on the design side makes a huge wave on the production side. Hence it is always good to design for assembly. Design for assembly (DFA) is really a process through which goods are made with an easy to assemble while in a production line or even before then, the prototyping phase. If your product contains less parts it will require a shorter period to put together. Hence the phrase “less is more”. Therefore reducing set up costs and time to assemble the actual product. Additionally, when the parts are supplied with features which will make it simpler to understand, move, orient and insert them, this can also reduce set up some time and set up costs. The decrease in the amount of parts within a set up has the additional advantage of generally reducing the all inclusive costs of parts within the set up. Normally, this is in which the major cost together with your use of the perception of assembly occurs. The bottom line is that our goal to keep the design and engineer simple stupid (KISS).
Design Approaches for Manufacturing:
The perception of set up may take variations. Within the 1960’s and 1970’s various rules and suggestions were suggested to be able to help designers consider set up problems throughout the design process. A number of these rules and suggestions were presented along with practical examples showing how set up difficulty might be improved. However, it wasn’t before the 1970s that statistical evaluation methods were designed to allow the perception of set up studies to become transported on existing and suggested designs.
The very first evaluation method was created at Hitachi and it was known as the Set up Evaluation Method (AEM). This process is dependant on the key of “one motion for just one part.” For additional complicated motions, a place-loss standard can be used and the simplicity of set up from the whole method is evaluated by subtracting points lost. The technique was initially developed to be able to rate assemblies for easy automatic set up.
Beginning in 1977, Geoff Boothroyd, based on an NSF grant in the College of Massachusetts Amherst, developed the look for Set up method (DFA), that could be employed to estimate time for manual set up of the product and the price of assembling the merchandise with an automatic set up machine. Recognizing that the most crucial element in reducing set up costs was the minimization of the amount of separate parts inside a product, he introduced three simple criteria that could be employed to determine theoretically whether the parts within the product might be eliminated or coupled with other areas. These criteria, along with tables relating set up time for you to various design factors influencing part grasping, orientation and insertion, could be employed to estimate total set up some time and to rate the caliber of an item design from your set up point of view. For automatic set up, tables of things could be employed to estimate the price of automatic feeding and orienting and automatic insertion from the parts with an set up machine.
Within the 1980s and 1990s, variations from the AEM and DFA methods happen to be suggested, namely: the GE Hitachi method which is dependant on the AEM and DFA the Lucas method, the Westinghouse method and many others that have been in line with the original DFA method. All methods are actually known as the perception of set up methods.
Implementation:
Most goods are put together by hand and also the original DFA way of manual set up is easily the most broadly used method and it has had the finest industrial impact around the world.
The DFA method, such as the AEM method, was initially provided by means of a guide in which the user would enter data on worksheets to acquire a rating for the simplicity of set up of the product. Beginning almost 30 years ago, Geoffrey Boothroyd and Peter Dewhurst created a computerized form of the DFA method which permitted its implementation inside a wide range of companies. With this work these were given many awards such as the National Medal of Technology. There are lots of printed types of significant savings acquired through the use of DFA. For instance, almost 30 years ago, Sidney Liebson, manager of producing engineering for Xerox, believed that his company would save vast sums of dollars through the use of DFA. In 1988, Ford Motor Company credited the program with overall savings approaching $1 billion. In lots of companies DFA is really a corporate requirement and DFA software programs are constantly being adopted by companies trying to obtain greater control of their manufacturing costs. There are lots of key concepts in the perception of set up.
Useful Links:
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