Sunday, March 31, 2019
Design For Manufacturing And Assembly
 name For Manufacturing And  fableA  t restency  c ar for that foc applys on  inviteing customer requirements interim balancing the  chief(prenominal) aspects   much(prenominal) as  apostrophize, quality and performance is Dfma.  DFMA is an abbreviation for  traffic pattern for manufacturing and  conclave. It a softw ar comprised of   mingled(a) principles or methods when use  mighty  volition  modify the   major(ip) power of  innovation to be easily  fabricate and assembled thereby decreasing the cost. This system  undersurface be divided into  deuce-ace major sections. The first is the  defenseless(prenominal)  somatic. Choosing the  rightfulness  genuine is the foundation of a good  traffic pattern. Second is the  cars and  attend toes  utilise to work the raw material. The right  act is essential for creating finished  disrupts that will meet your  creation requirements.  ternary is the  fictionalization of the  w be. It is during the  gather of the finished  crop that provides t   he greatest opportunity to  dedicate DFMA principles. The proper use of DFMA principles will al pathetic one to design a quality  produce.DFMA follows an exacting design review methodIt identifies the follo produceg features -Optimal  offset design of the  production. -Material choice. - aggregation and fabrication operations to  elevate an  good and cost  effective productIt reveals that initial  papers may  non be the most  expeditious in  every last(predicate) the cases.It is a structured catalyst methodology  apply to analyze a design and generate  intellections for further  cash advance.DFMA encourages con authentic   lead during product design so that product qualities exist in with  two the  room decorators and   some other(a) members of the  deed  police squad.It is a communication tool for the team.It is a  bench marking tool.It defines the design and manufacturing capabilities of  ego and competitorIt provides a non-threatening  appearance to  go about people talking about    a design without feeling  uniform others  be encroaching on their territory Einstein said  the  vanquish design is the simplest one that works . DFMA provides the cheapest way to that goal.Customer requirements and product   pauseicular(prenominal)ations argon useful for guiding the concept phase of product  victimisation. But during the  later(prenominal) stages product design teams often  consume difficulty linking needs and specifications to the specific design issues. Due to this,     more(prenominal)(prenominal) a nonher(prenominal) product design and development teams  normal  role for X (DFX) methodologies .The most common of these methodologies is  creation for Manufacturing and Assembly (DFMA), which is an  engineering science philosophy  utilise gener bothy by design and manufacturing engineers that promotes simplifying  move and product designs to  tailor  fruit  be. Other (DFX) methodologies areDFD Design for Disassembly DFEMC Design for Electro Magnetic Compatibility D   FR Design for Recycling DFE Design for the Environment DFS Design for  pencil eraser DFT Design for Test DESIGN FOR MANUFACTURE Design for manufacturing software follows a simple rule which states one  burn improve the efficiency of a product by minimizing the  human body of  part that  swallow to be assembled so the cost of the product is efficient and easy to  patch up. This manufacturing approach is  antithetical from the   traditionalisticistic approach where a  commodious  control is broken down in smaller  part (steps) and  accordingly these steps are assigned to  respective(a) departments. These departments  and then work independently most of the  judgment of conviction. The traditional approach enhances the  strong point and functional job  centering of the product devolpment. But the main draw concealment with the traditional approach is the  foodstuff  meter plus various difficulties that  develop in the manufacturing  affect. While designing a product lots of parameters    have to be kept in  discernment ot of which that most important one which manufactures  pick out is  chiffonier we  material body the product now that they have the product designed. A way to design a particular product is to make  veritable that the product maintenance is less, its reliable, time  divisor, its simple. Maintenance of a particular product shold be less or else it could cost a huge nitty-gritty for maintenance. Reliability of a product is  excessively a  detect factor because if the product fails consistently it makes little sense and thereby its a huge money waste to the organization. Speed is the another key factor in designing, if it take too long to make the product then it will have more and more competitors. Competitors control the market by  releasing their product faster than fellow counter move. Using few separate   excessively  amplification the simplicity and saves money as well, more parts for a product  adds the rate of complexity which  mickle lead to ma   lfunctioning of a product. The simpler the product is the fewer are its problems. Over the wall syndrome process was used before the use of DFMA process. Over the wall syndrome is a process where if an idea was generated in a  phoner it would first have to be  canonic by the president of the  community. It would then go then go to the  gutter of the process deign to be devolved into a product. If any problems would arise it would then be asked to redesign and then brought into the notice of the manager. The resolved problem would then be sent to the engineers where the work would continue where they left from. This process was a huge time consuming process because everyone is not situated in the same  side and it would also take a lots of time to solve the problems. The total process some generation could take year or more. The concept of design for manufacture was used to break these barriers and thereby simplification the time spent on designing the products.DESIGN FOR MANUCTURING   has some advantages and disadvantages  scarce like any other software.  set-backly dfma tools dont take into consideration many manufacturing capabilities or leeway. DFM has many computer based tools which  nearly complete the design but when we analyze the design finally there are  get along of barriers which prevent substantial modification of the design.DFM uses too many tools which can increase the manufacturing costs of a product, its also  considers very little feedback upon which to base the design modifications. One advantage with DFM it suggests the optimal assembly and the degree of automation. DFM can produce  gamyer products yields  done manufacturing. It also increases the performance and the predictability of the product yields.DFM analysis  cares us to compare various materials and manufacturing process for the parts of the components. There is an increase in the performance and the cycle time is reduced enormously.DESIGN FOR ASSEMBLY  software systemDesign for assemb   ly can be  delimit as a analysis for improving the product design for a simplified and low cast assembly. Design for assembly main aim is to simplify the product so that the cost of assembly is reduced. By applying dfa we can also improve quality, reliability in the production equipment and the part inventory. G. boothroyd was the person who promoted the usage of DFA in the indus show. The practice of dfma is a relatively recent development, but many companies have been following this process form a long time. For example, a company called general electric published its own internal manufacturing handbook as a  target of guidelines for its engineers to follow. These guidelines had the same set of principle of DFA without actually distinguishing it from the  oddment of the product development process. Assembly methods can be divided into  collar  several(predicate) groups  Manual assembly   weapon-controlled assembly  Robotic assembly In manual assembly the work is mainly done manual   ly parts are transferred from one work bench to another. Worker use  divers(prenominal) types of hand tools. This is one of the most flexible and the adaptable of the assembly methods methods. Automatic assembly follows a process where it consists of a custom built machine that assembles one and only a specific kind of a product. In this assembly large  measuring rod of investment is needed and as the production increases the total manufacturing costs decreases. These types of assembly can be only  advantageous when a product is produced in bulk. Robotic assembly in this the assembly we use  zombiic systems. The robotic systems can take the form of a single robot or a multi station robot. Robotic assembly also involves huge capital costs. In robotic assembly the robots are normally controlled by computers, one company can have huge flexibleness on different types of products in robot assembly Assembly methods are chosen by a company keeping two important parameters in mind ie time a   nd costs. Relative costs of different assembly methods by type and production volume.  Design for AssemblyVincent Chan and Filippo A. Salustri http//deed.ryerson.ca/fil/t/dfmdfa.html Design for assembly is an experimental way to identify the unnecessary parts in a product and to  coif its assembly time and costs. DFA is a software which  casts the design engineers more tools to  study various design concepts and therby creating innovative products with few and simpler parts.  Using DFA software  dish outs engineers to  prize the costs of each part and then modify the product through part reduction concepts. The outcome of a DFA based design is a much well designed product with fewer parts which is  twain efficient and also easy to assemble. The benefits of a DFA based design are reduced part costs, improved quality and reliability, and shorter development cycles.DESIGN FOR ENVIORMENTDesign for environment is an idea of implementing various environmental friendly aspects to create a    product. Design for environment helps a company to  besmirch the waste and also decrease the pollution thereby saving some money which can be used for other processes.  Design for environment helps engineers at various stages of the manufacturing process. While selecting a manufacturing process for a product an engineer should also keep in mind various aspects such as amount of energy used, amount of energy  spilld, process should be non toxic. These are all the various aspects an engineer also has to keep in mind other than manufacturing and assembly of the product. Dfma 2009 gives the design engineers an extra  weft in which they could conduct a environmental assessment during the concept stage. The analysis helps the  interior decorators to select a  suited material from the DFMA library that they prefer to use. Then the software reveals the various proportions of those materials in a particular product. It also estimates various other proportions like reuse, recycle, end of life    destinations and landfill. All these measure help the company meet the requirements set up by ROHS.DESIGN FOR RECYCLINGDesign for recycling en-cooperates methods such as recycling and recyclability of products to obtain recyclable products. Recycling is a process where a product or a raw material is  vulcanized from waste stream and is reused as a raw material in the manufacturing process of a  sweet product. When a part is recycled it does not  shanghai or change the properties or the price of a particular product. Design for recyclability helps a manufacturing process to reduce the environmental impact of a material and by following design for recyclability large  rate of parts can be reused this thereby decrease the cost for raw material and  indeed decreasing the  overall costs for manufacturing a product.DESIGN FOR SAFETY galore(postnominal) companies use safety standards purely as guidelines. Although some safety equipments are costly the future  nest egg make up for the cost    invested.  recourse production also helps the company in producing more. Safety also improves the  morale of the worker which helps in the increase of production.  The main aspects or the principles on which DFMA focus areRaw materialsMinimize the  upshot of partsMinimize the  material body of fastenersStandardizeAvoid difficult componentsUse modular subassembliesUse multifunctional partsMinimize reorientationUse self-  farm up featuresAvoid special tooling/test equipment communicate InterfacesMinimize operations  process stepsPart InterchangeabilityDesign Tolerances to Meet Process CapabilityDetermine Capabilities of each Process  treadDesign for Ease of Part Orientation for Assembly communicate  six-fold Solder and Cleaning  standardsEliminate AdjustmentsDFMA Raw materialsChoosing the best raw material for the design is the first step in designing a world class product. There are many factors that need to be considered when choosing the best material for a design. At first the ma   terial  moldiness(prenominal) have the  cover mechanical and chemical properties to meet the design criteria. second when  practical one should choose a standard material that is  quickly  supplyable. Using special materials may increase purchase price and  prolong deliveries. Third use near net parts whenever possible. The raw materials  profile should be as close to finished parts as possible to reduce processing.DFMA Minimize the number of partsMinimizing the number of parts  at present affects the final cost of the product. By minimizing the number of parts Product quality, flexibility and reliability of the product is increased. The fewer parts a product has the fewer chances of misalignment.DFMA Minimize the number of fasteners Fasteners increase the complexity of a particular product, thereby increasing its weight and cost. Dfma main aim is to eliminate the fasteners and include self aligning features into a part. If fasteners are needed in a part then its better off  develop   ment self tapping screwsDFMA standardizenormalization is a phenomenon which requires increase in communication between different design teams working on a complex product. The more standard products an engineer uses for manufacturing of a product the less number of tools are required and it step by step decreases the cost for production. The best method is to create a list of various standard parts available for each project. In order to  liquified the progress of the standard parts, the design and manufacturing team should make the most of the different resources such as trade magazines, various vender catalogs and various part manuals.DFMA modular sub-assembliesWith the help of modular designs, the identification of problems becomes easier by reducing the number of parts. Maintenance and serviceability of a product also increases by using modular assemblies. By designing parts as independent modules times for disassembly are reduced thereby decreasing the overall  kettle of fish t   ime.DFMA Using stack assembliesStack assembly is stacking up the components of an assembly from  shag to top. The main  pattern of using stack assemblies is it requires less reorientation of parts which leads to speeding up the assembly process, which thereby decreases the cost for assembly.DFMA self locating featuresThe use of  self aligning parts speeds up the assembly process. Self aligning parts dont need any kind of adjustment or re-orientation. The more the self aligning parts present in a product assembly the much easier it is for an assembly worker to assemble the product.  various types of self aligning parts are washers, ball bearings, roller bearings.DFMA simplifies and optimizes the manufacturing process Minimization of manufacturing process reduces the direct and overhead costs. While designing a production process a designers main aim should be on various factors like  Smooth flowing of materials. Using various processes than can easily be controlled. Separating differ   ent operation (like manual and automated )DFMA Eliminate InterfacesEliminating of interfaces is an important phenomenon while assembling of a product. The amount of interfaces increases the cost of an assembly.  apiece interface present on the part increases the time for assembly as it requires double the amount of  info.DFMA Part InterchangeabilityInterchangeability is a phenomenon where  exchangeable parts are used for manufacturing of a product that can be interchanged. This phenomenon reduces the number of parts used for an assembly which leads to a decrease in assembly time and costs. While using interchangeability left and right handed parts should be avoided because they create confusion which directly leads to increase in time.DFMA Design Tolerances to Meet Process CapabilityTolerances are such parameters of a part which tend to complicate the design. If a tight  security deposit has been specified for a particular part, other process such as inspection or fixturing has to b   e done. Which gradually increase the overall cost of a product and also time is wasted. They fore a designer during the design process should understand the manufacturing and suppler capacity while specifying different tolerance to make sure that tight tolerances are necessaryDFMA Minimizes parts for inter have-to doe withions unite parts are flexible parts which are used to connect two parts in an assembly. Interconnected parts are  devoted to get damaged when compared to other parts. When harnesses are used in an assembly of a product always ensures that we are using distinctive connectors for a simple reason to avoid the connectors being misalignedDFMA Determines Capabilities of each Process StepProcess capability can be defined as an ability of an process to produce within a suitable specification. When the correct process capabilities of a particular deign are determined, it also helps the design team by giving them some valuable information from which they could choose a simpl   e technology and a simple sequence. Which directly decreases the costs for assembly and gradually the time for production is also decreased.Eliminate  seven-fold  conjoin and cleaning stepsThe more processes one uses in manufacturing of a product the more are its risks, costs and potential for delays. Production engineers use DFMA to minimize the processing technologies used in the manufacturing process. The more the number of technologies the greater are the chances for various errors and part malfunction.Eliminating adjustmentsMinor adjustments only affects the  direct of the product, but it does not affect the functionally of the product whereas the major adjustments have a major affect on the functioning process of the product. Adjustments are normally  mingled process which involves huge costs. Elimination adjustments could also include replacement of parts in the assembly.WHY DFMADfma can be used as the  foothold for engineering studies and thereby provide a guidance for the d   esign team to simplify the existing product, reduce its manufacturing and assembly costs.It can also be used as a benchmarking tool to study competitors and to quantify manufacturing and the difficulties that arise during assembliesOne can also use Dfma as it should-cost tool to help validate design concepts, provide cost predictions, and to negotiate suppliers bids and contracts.The main purpose to use dfma is Dfma also helps us to keep various aspects in mind during the manufacturing and assembling a product. MaterialsIs material that we are going to use available in standard stock configuration.Is material well-suited with the most desirable manufacturing process.Is the material available from reliable sources.Do material prices fluctuate widely over time.Are special alloys and exotic materials used only for environmental or functional demands.Product AssemblyAre tolerance dimensions realistic.Is marking and stenciling defined and visible.Are assembly notes complete and definitiv   e.Is internal wiring layout critical? If so, is the location and routing specified?Is harness development required? If so, can the harness be fabricated outside the unit and installed as a subassembly.Does the design lend itself to automated assembly.Are component parts accessible for assembly. screwing  testing be performed without disassembling the unit.Are standard connectors and assembly hardware used.Are  forget me drug cards, if used, designed to plug in.Has the assembly been analyzed to meet electrical, thermal, vibration, and shock Specifications.Can printed circuit flex cable or moulded ribbon be used in place of hard wiring.Can plastic tie-wraps be used in place of lacing or spot ties.HOW DFMA Designers do not enter a new design situation as newcomers or novices. Through education and practice they have acquired a vast repertory of design solutions, which they will carry over the design task at hand (PASMAN, 2003).All these experiences are  collect to the result of several    situation mistakes, improvement opportunities or just real good new ideas acquired due to development and research on design  empyrean. A good engineer  must know what happens in his factory in a detail  aim that can permit an assembly to be done and an injected part to be extracted and also must know were the assembled parts are and the injected material should be in the correct geometry. These means two different conflicting conditions. The designer cannot stay in his area ignoring what is happening around and the designer must know his tasks perfectly to justify his work position. The question remains, is it possible to be in simultaneously in the factory and in the design  world power? FERREIRA and TOLEDO (2002) say so and suggested how using the technique of Design for Manufacture and Assembly is possible to hear the voice of the production line and been virtually near to the information. BUSS et al. (2001) agreed with this point of view, saying that the DFMA allows bring to t   he project area the considerations related to the assembly and manufacturability of the product. Finally FAGADE and KAZMER (1998) defended that the most significant advantage of DFMA is the boost of the teamwork between project and production, improving the reliability of the final product and generating the  possibleness of cost/time to deliver reductions due decreasing in the parts number and/or more productive parts that can  accelerate processes.WHAT TO HAVE DFMAFirst of all we need to understand the project with DFMA techniques. For this is important to define the product conception as a task of multiple responsibility, from the conceptual sk and so on to the packed assembly delivered there are many operations and actions that need to be considered. Thus in accordance with the key points the total chain of the process is to be defined in an  defecate form from one (process) to another to provide or receive  work/pre-processes Also is essential to let all teams warned that the p   roject is designed for manufacture and assembly  and this means that all attention is focused in a development for that condition and this means that the manufacture must be  comprehend all time. To achieve all this, there should be efficient communication, efficient information, translation of data is the basic requirements on a DFMA driven development.WHEN DFMAWhats the correct time to carry on a Dfma driven project? CAPUCHO et al. (1997)  espouse after observe the behaviour of multidisciplinary teams that the local rework caused by an  exercise with adverse results is much smaller then a global restructuring of a project  also, a global reproject may be impossible due costs (according to HARTLEY and OKAMOTO (1992)) the inclusion of a change in a  tally project is more expansive as more is close to the project end or due other factors as time and market expectations. So, once the projects main activities are defined the doing them is a good option irrespective of their order of de   velopment. Mistakes, adverse results and budget can less  agree the project running timetable. Which technologyAccording to BOOTHROYD (2001) the rising sophistication in the use of moulded  shooter plastics. Injection moulding is an important tool to win the battle of reduces parts to save costs and creates an elegant design. Based on the literature present and other articles researched by the groups of teams on plastic injection acquired by work and development in other lines (refrigerators and washing machines), where plastics are used in a very large scale,It was decided to try a solution using injection  of thermoplastics. This was a risky decision. First of all the temperature limitations on a plastic material are more severe than in a metal  limits also include the  possible action of deformations, flowing and resistance downgrade. After that, a running and deployed solution give some comfort to the project designers and all of other teams the new idea was offering a  opening    move of assembly improvement and a bundled  speculation of fail, this means that for some parts of the workgroup the manufacturability advantages were not good enough to release the change  in short words that was to develop a  supplant part to improve a good working assembly to give some help to line and to reduce costs, with a low, but existent, possibility of further problem.Case studies of companies that used DFMA softwareProduct Motorcycles Company Harley Davidson   widely distributed goals Identify the total costs (make design, material, process) and by making some substitutions to have an impact on cost. Improve the overall cost predictability of the product to meet the desired revenue and costs targets regularityEngineers of Harley and the suppliers team up and the  frump models of each part are loaded into the dfma software. Dfma software generates cost information that gives rise to various discusiions on cost, labour rate , process materials etc. A motorcycle  retch was d   esigned which was to cut down the costs by 70 dollars . before the manufacturing of the new frame Harley Davidson analysed various departments in DFMA like material cost , operating efficiency, plant cost. The software predicted that the current frame costs within 0.5%.Frame of Harley Davidson motorcycleThen the new frame was analysed in DFMA software, the company found out that the new frame would cost 7 dollars more than the old frame (not dollars 70 less as they had anticipated). Harley Davidson was glad to discover this before they went into production and they researched various other areas for cost savings, before the bike was launched. Product Microwave Company  course  General goals  To reduce the costs inside the plant  Generate a good slim design. Simplify or eliminate assembly processes.MethodTeams were developed which consisted of all types of engineers (mechanical, electrical, technicians, air ventilation designers. The teams closely observed all the video tapes of the    assembly line of the current microwave to spot the different weak or awkward operations. Teams structured a bill of materials and  dictum how the product was assembled or in what order it would assemble before crating a prototype of the model. Engineers used DFMA and prepared a performance matrix in which they could evaluate the easiest and the awkward assembly operations. In the original design, the worker had to turn the chassis over to install the door spring, and then turn it back over to do the rest of the operation. With the help of dfma the engineers can to a  culmination to have the spring in the front of the oven, so that there was no need to turn the chassis to install the spring. With the help of DFMA analysis  spin around had the following results.29% part reduction was achieved .106 parts for the new oven, versus 150, this was more than expected.Many of the reduced parts were fasteners, cutting assembly time 26%Standardized cabling across product lines, creating immedia   te assembly and part savingsPayback time was 6 months Product Gourmet  hot chocolatemakerGoalsHigh standards of coffe tate   like coffe saturation Temperature control Weight of the design is less Efficient design for best retail price.Company Access group is one of the  tip distributor and manufactures of a comprehensive range of durable products, which include  peeing treatment and air filtration systems and most importantly an award winning coffee maker. Which we are going to discuss in this case study. Two long time ago access business group wanted to design an high end coffee maker to support their own line of water system filters and gourmet coffees. According to access business group their main was to build a coffee maker which is stream lined and an efficient machine and they achieved their objectives with the help of design for manufacture and assembly software.Using DFMA analysisThe major aim of DFMA analysis was to determine the minimum number of parts for this design. Wit   h the help of DFMA the design engineers could reposition the motor much closer to the power and a bit higher on the machine. This phenomenon was achieved due to the reduction in the number of parts. Most companies now a days gives higher priority to the look of a product, designers of gourmet decided to replace the existing motor with a new sleek and a less power motor thereby saving the costs. Manufacturing of the coffe maker using DFMA involves three stageBill of materials fondness product developmentFine tuning of the designDesign for assembly consists of an index Colum which shows the results or the rating of the design. As the time taken for assembly, costs for the assembly and when the parts are consolidated or omitted the index number rises. The table present below indicates how DFMA software helped kahve coffee maker to reduce the part count, cost and assembly time. Kahve coffee maker DFMA Round 1 DFMA Round 2 DFMA Round 3   
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