tailieunhanh - Designing Capable and Reliable Products Episode 2 Part 7

Tham khảo tài liệu 'designing capable and reliable products episode 2 part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Appendix III 305 Placement in product development DFA DFM should be performed during concept design leading into the detailed design stage to revise the product structure. Application of the technique CSC s DFA MA methodology The analysis is carried out in four main stages see Figure 8 . 1. Functional analysis. The methodology enables each part to be classified as essential A parts or non-essential B parts. Given this awareness redesigns can be evolved around the essential components from which reduced part count normally results. 2. Manufacturing analysis. Component costs are calculated by considering materials manufacturing processes and aspects such as complexity volume and tolerance. This allows ideas for part count reduction to be tested since combining parts can lead to more complex components and changes to manufacturing processes. 3. Handling analysis. Components must be correctly orientated before assembly can take place. The difficulty achieving this by either manual or mechanical means can be assessed using the analysis. Components receiving high ratings should be modified to give an acceptable rating. Mistake proofing or Poka Yoke devices DFA MA ANALYSIS Figure 8 DFA MA flow chart CSC 1995 306 Appendix III can be installed in the manufacturing and assembly processes to help ensure zero defects. 4. Fitting analysis. For this to be possible an assembly sequence plan must be constructed and the difficulty of assembling each part in the sequence rated using the design for assembly analysis tables. Difficult assembly tasks and non-value added processes are revealed as candidates for correction by redesign. Simple concepts such as the ability to assemble in a layer fashion can result in major cost savings. The assembly analysis stages 3 and 4 have the following measures of performance which are accepted as an indication of good design Functional analysis gives a Design Efficiency Essential Parts Total Parts 60 Handling analysis gives a Handling Ratio Total .