{"id":30,"date":"2023-04-18T11:30:15","date_gmt":"2023-04-18T11:30:15","guid":{"rendered":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/?post_type=chapter&#038;p=30"},"modified":"2023-11-21T13:04:55","modified_gmt":"2023-11-21T13:04:55","slug":"chapter-6","status":"publish","type":"chapter","link":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/chapter\/chapter-6\/","title":{"raw":"Chapter 6","rendered":"Chapter 6"},"content":{"raw":"<h2>Chapter 6: Example DFMA Analysis Using DFA Index<\/h2>\r\n<h3>Introduction<\/h3>\r\nNow that the foundation has been laid for the application of DFMA, we are ready for implementation.\u00a0 This chapter will present a step-by-step DFMA design analysis using a new measure called the DFA index.\r\n\r\nKey Terms:\r\n\r\nManual Assembly : product assembled using human labor.\r\n\r\n[pb_glossary id=\"159\"]Hard Automation[\/pb_glossary] : product assembled using machines dedicated to that product.\r\n\r\n[pb_glossary id=\"158\"]Soft Automation[\/pb_glossary] : product assembled using reconfigurable robots.\r\n\r\n[pb_glossary id=\"160\"]Semi-Automation[\/pb_glossary] : product assembled using mix of manual and automated methods.\r\n<h3>Determining Part Size<\/h3>\r\nRectangular Parts\r\n<ul>\r\n \t<li>Find the smallest rectangle that encloses the part.<\/li>\r\n \t<li>Thickness = shortest side<\/li>\r\n \t<li>Size is the length of the longest side.<\/li>\r\n<\/ul>\r\nCylindrical Part Thickness\r\n<ul>\r\n \t<li>Cylindrical or regular polygon (5+ sides) cross-section and diameter is less than the length.<\/li>\r\n \t<li>Thickness = radius of the smallest cylinder that will enclose part.<\/li>\r\n<\/ul>\r\n<h3>DFA Index Definition<\/h3>\r\nThe design for assembly (DFA) Index is an efficiency measure which compares the current design to the theoretically simplest design with the minimum number of parts.\u00a0 The DFA is expressed as a percentage (%) and as DFMA is applied the percentage should increase with 100% being the maximum value.\u00a0 DFA Index can be calculated using a theoretical time to handle and assemble; however, whenever possible the actual time to handle and assemble will be utilized.\u00a0 However, in the early design stages, we often don\u2019t yet know these actual times.\u00a0 Therefore, it is critical that individuals from the assembly process be part of the DFMA team and provide input on challenges with the existing design as well as estimates of actual handling and assembly times.\u00a0 The use of DFMA analysis software can be very beneficial in making more accurate estimates of time and providing added the benefit of monitoring against industry best practices and standard times.\r\n\r\n<strong>E<sub>MA<\/sub> = 100 x N<sub>MIN<\/sub> \u00d7 T<sub>A<\/sub> \u00f7 T<sub>MA<\/sub><\/strong>\r\n\r\nN<sub>MIN<\/sub> = theoretical minimum part count\r\n\r\nT<sub>A<\/sub> = theoretical minimum handling and assembly time for any part (2.93 seconds, often rounded to 3 seconds)\r\n\r\nT<sub>MA<\/sub> = Actual total handling and assembly time for the design concept\r\n\r\n&nbsp;\r\n\r\n[h5p id=\"25\"]\r\n<h3>DFMA Process<\/h3>\r\n<strong>Initial Design (Baseline) Evaluation<\/strong>\r\n<ul>\r\n \t<li>Step 1:\u00a0 Begin with a new concept design (or an existing product assembly) with a full bill of materials and dimensional data.<\/li>\r\n \t<li>Step 2:\u00a0 Determine the current total number of components<\/li>\r\n \t<li>Step 3:\u00a0 Determine the cost of each component<\/li>\r\n \t<li>Step 4:\u00a0 Determine the Total Component Part Costs<\/li>\r\n \t<li>Step 5:\u00a0 Determine the Steps to Assemble the product<\/li>\r\n \t<li>Step 6:\u00a0 Determine the Handling Time each part with consideration to product geometry, symmetry, and handling challenges.<\/li>\r\n \t<li>Step 7:\u00a0 Determine the Assembly time for each component with consideration to tools required, holding methods, and assembly challenges.<\/li>\r\n \t<li>Step 8:\u00a0 Determine the Total Handling, Assembly and the combined Handling and Assembly time.<\/li>\r\n<\/ul>\r\n<strong>Evaluate Initial Design to Determine Theoretical Minimum Parts<\/strong>\r\n<ul>\r\n \t<li>Step 9:\u00a0 Use the DFMA Functional Analysis to Determine which parts are <strong>essential<\/strong><\/li>\r\n \t<li>Step 10:\u00a0 Clearly identify (list)) these essential parts<\/li>\r\n \t<li>Step 11:\u00a0 Total the number of essential parts (T<sub>min<\/sub>)<\/li>\r\n \t<li>Step 12:\u00a0 Calculate the DFA Index of the Initial Concept<\/li>\r\n<\/ul>\r\n<strong>Explore Design Improvements (Redesign) for Manufacture and Assembly<\/strong>\r\n<ul>\r\n \t<li>Step 9:\u00a0 Brainstorm design changes with an emphasis on removing or minimizing the <strong>non-essential<\/strong> parts.<\/li>\r\n \t<li>Step 10: For each concept, clearly identify <strong>what is being changed and why<\/strong>.<\/li>\r\n \t<li>Step 11:\u00a0 Develop a new bill of materials<\/li>\r\n \t<li>Step 12:\u00a0 Determine the current total number of components<\/li>\r\n \t<li>Step 13:\u00a0 Determine the cost of each component<\/li>\r\n \t<li>Step 14:\u00a0 Determine the Total Component Part Costs<\/li>\r\n \t<li>Step 15:\u00a0 Determine the Steps to Assemble the product<\/li>\r\n \t<li>Step 16:\u00a0 Determine the Handling Time each part with consideration to product geometry, symmetry, and handling challenges.<\/li>\r\n \t<li>Step 17:\u00a0 Determine the Assembly time for each component with consideration to tools required, holding methods, and assembly challenges.<\/li>\r\n \t<li>Step 18:\u00a0 Determine the Total Handling, Assembly and the combined Handling and Assembly time.<\/li>\r\n \t<li>Step 19:\u00a0 Calculate the DFA Index of the Initial Concept using the same Tmin from step 11.<\/li>\r\n<\/ul>\r\n<strong>Evaluate the potential DFMA improvement<\/strong>\r\n\r\nStep 20:\u00a0 For each concept, compare the new concept to the initial design in the following areas:\r\n<ul>\r\n \t<li>DFA Index<\/li>\r\n \t<li>Number of component parts<\/li>\r\n \t<li>Total Component part costs<\/li>\r\n \t<li>Total time to Handle and Assemble<\/li>\r\n \t<li>Total Handling and Assembly Costs<\/li>\r\n \t<li>Total Cost<\/li>\r\n<\/ul>\r\nFor more information check out the following links to additional information:\r\n<ul>\r\n \t<li><a href=\"https:\/\/www.dfma.com\/forum\/2019pdf\/devenish.pdf\">Conducting a step-by-step DFA analysis<\/a><\/li>\r\n \t<li><a href=\"https:\/\/www.scribd.com\/document\/395875963\/final-submission\">Design for Assembly Example : Ball Point Pen<\/a><\/li>\r\n<\/ul>\r\n[h5p id=\"24\"]\r\n<h3>Design Analysis<\/h3>\r\nWhat is included in the total cost?\r\n<ul>\r\n \t<li>Material cost for component<\/li>\r\n \t<li>Tooling costs (mold cost) = Total cost \/ # of units to be produced<\/li>\r\n \t<li>Setup of Machinery Costs<\/li>\r\n \t<li>Handling and assembly cost for entire assembly<\/li>\r\n \t<li>Overhead costs for facilities, support staff, etc.<\/li>\r\n<\/ul>\r\nDFA Software:\r\n<ul>\r\n \t<li>Calculates handling and assembly time and costs<\/li>\r\n \t<li>DFA index<\/li>\r\n \t<li>Allows design modification to show DFA improvements.<\/li>\r\n<\/ul>\r\nDFM Software:\r\n<ul>\r\n \t<li>Calculates material and tooling costs + equipment set up and overhead<\/li>\r\n<\/ul>","rendered":"<h2>Chapter 6: Example DFMA Analysis Using DFA Index<\/h2>\n<h3>Introduction<\/h3>\n<p>Now that the foundation has been laid for the application of DFMA, we are ready for implementation.\u00a0 This chapter will present a step-by-step DFMA design analysis using a new measure called the DFA index.<\/p>\n<p>Key Terms:<\/p>\n<p>Manual Assembly : product assembled using human labor.<\/p>\n<p><button class=\"glossary-term\" aria-describedby=\"30-159\">Hard Automation<\/button> : product assembled using machines dedicated to that product.<\/p>\n<p><button class=\"glossary-term\" aria-describedby=\"30-158\">Soft Automation<\/button> : product assembled using reconfigurable robots.<\/p>\n<p><button class=\"glossary-term\" aria-describedby=\"30-160\">Semi-Automation<\/button> : product assembled using mix of manual and automated methods.<\/p>\n<h3>Determining Part Size<\/h3>\n<p>Rectangular Parts<\/p>\n<ul>\n<li>Find the smallest rectangle that encloses the part.<\/li>\n<li>Thickness = shortest side<\/li>\n<li>Size is the length of the longest side.<\/li>\n<\/ul>\n<p>Cylindrical Part Thickness<\/p>\n<ul>\n<li>Cylindrical or regular polygon (5+ sides) cross-section and diameter is less than the length.<\/li>\n<li>Thickness = radius of the smallest cylinder that will enclose part.<\/li>\n<\/ul>\n<h3>DFA Index Definition<\/h3>\n<p>The design for assembly (DFA) Index is an efficiency measure which compares the current design to the theoretically simplest design with the minimum number of parts.\u00a0 The DFA is expressed as a percentage (%) and as DFMA is applied the percentage should increase with 100% being the maximum value.\u00a0 DFA Index can be calculated using a theoretical time to handle and assemble; however, whenever possible the actual time to handle and assemble will be utilized.\u00a0 However, in the early design stages, we often don\u2019t yet know these actual times.\u00a0 Therefore, it is critical that individuals from the assembly process be part of the DFMA team and provide input on challenges with the existing design as well as estimates of actual handling and assembly times.\u00a0 The use of DFMA analysis software can be very beneficial in making more accurate estimates of time and providing added the benefit of monitoring against industry best practices and standard times.<\/p>\n<p><strong>E<sub>MA<\/sub> = 100 x N<sub>MIN<\/sub> \u00d7 T<sub>A<\/sub> \u00f7 T<sub>MA<\/sub><\/strong><\/p>\n<p>N<sub>MIN<\/sub> = theoretical minimum part count<\/p>\n<p>T<sub>A<\/sub> = theoretical minimum handling and assembly time for any part (2.93 seconds, often rounded to 3 seconds)<\/p>\n<p>T<sub>MA<\/sub> = Actual total handling and assembly time for the design concept<\/p>\n<p>&nbsp;<\/p>\n<div id=\"h5p-25\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-25\" class=\"h5p-iframe\" data-content-id=\"25\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"DFA Index\"><\/iframe><\/div>\n<\/div>\n<h3>DFMA Process<\/h3>\n<p><strong>Initial Design (Baseline) Evaluation<\/strong><\/p>\n<ul>\n<li>Step 1:\u00a0 Begin with a new concept design (or an existing product assembly) with a full bill of materials and dimensional data.<\/li>\n<li>Step 2:\u00a0 Determine the current total number of components<\/li>\n<li>Step 3:\u00a0 Determine the cost of each component<\/li>\n<li>Step 4:\u00a0 Determine the Total Component Part Costs<\/li>\n<li>Step 5:\u00a0 Determine the Steps to Assemble the product<\/li>\n<li>Step 6:\u00a0 Determine the Handling Time each part with consideration to product geometry, symmetry, and handling challenges.<\/li>\n<li>Step 7:\u00a0 Determine the Assembly time for each component with consideration to tools required, holding methods, and assembly challenges.<\/li>\n<li>Step 8:\u00a0 Determine the Total Handling, Assembly and the combined Handling and Assembly time.<\/li>\n<\/ul>\n<p><strong>Evaluate Initial Design to Determine Theoretical Minimum Parts<\/strong><\/p>\n<ul>\n<li>Step 9:\u00a0 Use the DFMA Functional Analysis to Determine which parts are <strong>essential<\/strong><\/li>\n<li>Step 10:\u00a0 Clearly identify (list)) these essential parts<\/li>\n<li>Step 11:\u00a0 Total the number of essential parts (T<sub>min<\/sub>)<\/li>\n<li>Step 12:\u00a0 Calculate the DFA Index of the Initial Concept<\/li>\n<\/ul>\n<p><strong>Explore Design Improvements (Redesign) for Manufacture and Assembly<\/strong><\/p>\n<ul>\n<li>Step 9:\u00a0 Brainstorm design changes with an emphasis on removing or minimizing the <strong>non-essential<\/strong> parts.<\/li>\n<li>Step 10: For each concept, clearly identify <strong>what is being changed and why<\/strong>.<\/li>\n<li>Step 11:\u00a0 Develop a new bill of materials<\/li>\n<li>Step 12:\u00a0 Determine the current total number of components<\/li>\n<li>Step 13:\u00a0 Determine the cost of each component<\/li>\n<li>Step 14:\u00a0 Determine the Total Component Part Costs<\/li>\n<li>Step 15:\u00a0 Determine the Steps to Assemble the product<\/li>\n<li>Step 16:\u00a0 Determine the Handling Time each part with consideration to product geometry, symmetry, and handling challenges.<\/li>\n<li>Step 17:\u00a0 Determine the Assembly time for each component with consideration to tools required, holding methods, and assembly challenges.<\/li>\n<li>Step 18:\u00a0 Determine the Total Handling, Assembly and the combined Handling and Assembly time.<\/li>\n<li>Step 19:\u00a0 Calculate the DFA Index of the Initial Concept using the same Tmin from step 11.<\/li>\n<\/ul>\n<p><strong>Evaluate the potential DFMA improvement<\/strong><\/p>\n<p>Step 20:\u00a0 For each concept, compare the new concept to the initial design in the following areas:<\/p>\n<ul>\n<li>DFA Index<\/li>\n<li>Number of component parts<\/li>\n<li>Total Component part costs<\/li>\n<li>Total time to Handle and Assemble<\/li>\n<li>Total Handling and Assembly Costs<\/li>\n<li>Total Cost<\/li>\n<\/ul>\n<p>For more information check out the following links to additional information:<\/p>\n<ul>\n<li><a href=\"https:\/\/www.dfma.com\/forum\/2019pdf\/devenish.pdf\">Conducting a step-by-step DFA analysis<\/a><\/li>\n<li><a href=\"https:\/\/www.scribd.com\/document\/395875963\/final-submission\">Design for Assembly Example : Ball Point Pen<\/a><\/li>\n<\/ul>\n<div id=\"h5p-24\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-24\" class=\"h5p-iframe\" data-content-id=\"24\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Manual Assembly Videos\"><\/iframe><\/div>\n<\/div>\n<h3>Design Analysis<\/h3>\n<p>What is included in the total cost?<\/p>\n<ul>\n<li>Material cost for component<\/li>\n<li>Tooling costs (mold cost) = Total cost \/ # of units to be produced<\/li>\n<li>Setup of Machinery Costs<\/li>\n<li>Handling and assembly cost for entire assembly<\/li>\n<li>Overhead costs for facilities, support staff, etc.<\/li>\n<\/ul>\n<p>DFA Software:<\/p>\n<ul>\n<li>Calculates handling and assembly time and costs<\/li>\n<li>DFA index<\/li>\n<li>Allows design modification to show DFA improvements.<\/li>\n<\/ul>\n<p>DFM Software:<\/p>\n<ul>\n<li>Calculates material and tooling costs + equipment set up and overhead<\/li>\n<\/ul>\n<div class=\"glossary\"><div class=\"glossary__tooltip\" id=\"30-159\" hidden><p>Pros:<br \/>\nLittle or no labor<br \/>\nLess expensive than soft automation<\/p>\n<p>Cons:<br \/>\nLimited to single product\/family<br \/>\nLittle flexibility (improving)<br \/>\nHigh volumes<\/p>\n<\/div><div class=\"glossary__tooltip\" id=\"30-158\" hidden><p>Pros:<br \/>\nFlexibility and repeatability<\/p>\n<p>Cons:<br \/>\nCapital cost and changeover time<\/p>\n<\/div><div class=\"glossary__tooltip\" id=\"30-160\" hidden><p>Pros:<br \/>\nPart presentation<br \/>\nOvercomes some human limitations<\/p>\n<p>Cons:<br \/>\nCost of labor<\/p>\n<\/div><\/div>","protected":false},"author":20,"menu_order":6,"template":"","meta":{"pb_show_title":"","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[49],"contributor":[],"license":[],"part":3,"_links":{"self":[{"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/pressbooks\/v2\/chapters\/30"}],"collection":[{"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/wp\/v2\/users\/20"}],"version-history":[{"count":6,"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/pressbooks\/v2\/chapters\/30\/revisions"}],"predecessor-version":[{"id":162,"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/pressbooks\/v2\/chapters\/30\/revisions\/162"}],"part":[{"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/pressbooks\/v2\/parts\/3"}],"metadata":[{"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/pressbooks\/v2\/chapters\/30\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/wp\/v2\/media?parent=30"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/pressbooks\/v2\/chapter-type?post=30"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/wp\/v2\/contributor?post=30"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.palni.org\/designmanufactureassembly\/wp-json\/wp\/v2\/license?post=30"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}