{"id":11010,"date":"2021-09-28T19:29:41","date_gmt":"2021-09-28T16:29:41","guid":{"rendered":"https:\/\/fractory.com\/?p=11010"},"modified":"2024-01-26T14:21:10","modified_gmt":"2024-01-26T12:21:10","slug":"design-for-assembly-dfa","status":"publish","type":"post","link":"https:\/\/fractory.com\/design-for-assembly-dfa\/","title":{"rendered":"Design for Assembly"},"content":{"rendered":"

Although Design for Assembly (DFA) and Design for Manufacturing (DFM) principles are often looked at as one subject and combined into Design for Manufacturing and Assembly (DFMA)<\/a>, they are separate methodologies.<\/p>\n

Design for Assembly, a part of the Design for X (DFX)<\/a> family, is the optimisation of the product and the assembly process, while Design for Manufacturing focuses on materials selection and manufacturing processes.<\/p>\n

Over 70% of the product\u2019s final cost is determined during the design process and the remaining 30% during manufacturing. Addressing potential issues at those early stages of product development will help you to get it right the first time or at least require less prototyping and fewer product iterations.<\/p>\n

What Is Design for Assembly?<\/h2>\n

Design for Assembly (DFA), simplifies the product\u2019s structure by reducing the number of components and minimising the number of assembly operations required. The aim is to make the manufacturing process easier, faster and more consistent, therefore more productive.<\/p>\n

The basic Design for Assembly process involves asking three questions for each part in an assembly:<\/p>\n

    \n
  1. Does the part have to move relative to other parts in the assembly?<\/li>\n
  2. Is the part made of different material for aesthetic or functional reasons?<\/li>\n
  3. Does the part have to be separate to guarantee access to other parts or to be able to carry out repair and maintenance<\/a>?<\/li>\n<\/ol>\n

    When answering no to all of the questions above, the part should most likely be combined with another part in the assembly.<\/p>\n

    Manual & Automated Assembly<\/h3>\n

    Most products are assembled manually and the original DFA methods for manual assembly had an enormous impact on productivity. It was quickly realised that the most important aspect in optimising for Design for Assembly was keeping the number of components to a minimum and removing unnecessary features that do not add to the functionality of the product.<\/p>\n

    Different forms of guidelines to help designers were proposed in the 60s and 70s, but it wasn’t until the late 1970s that numerical evaluation methods were developed. This made estimating the time and cost difference between manual and automatic assembly easier.<\/p>\n

    The key principles for both manual and automatic assembly are similar. There are some differences though, since compared to a human, robots are quite limited in their motion range and capabilities. In Design for Automated Assembly (DFAA), a lot of the focus shifts to different tools and grippers that can be fitted onto robots, like vacuum cups, parallel grippers, three-finger grippers and electro-magnets.<\/p>\n

    \"Sony
    Sony Walkman used top-down assembly<\/figcaption><\/figure>\n

    You should aim to minimise the need for reorientation during assembly with both manual and automated assembly processes, but it is particularly crucial for automation. The success story of Sony Walkman is a good example of assembly automation, incorporating single-axis assembly with only straight down moves (Top-down assembly).<\/p>\n

    When following Design for Assembly guidelines with more complex assemblies, it might not be always possible to eliminate reorientation completely, but try to bring it to a minimum.<\/p>\n

    \n
    \n Scale Your Manufacturing from Prototyping to Series<\/span>\n\n