Unit 3 cim
- 1. UNIT 3 CELLULAR MANUFACTURING Group Technology(GT), Part Families – Parts Classification and coding – Simple Problems in Opitz Part Coding system – Production flow Analysis – Cellular Manufacturing – Composite part concept – Machine cell design and layout – Quantitative analysis in Cellular Manufacturing – Rank Order Clustering Method - Arranging Machines in a GT cell – Hollier Method – Simple Problems.
- 2. GROUP TECHNOLOGY ❧It’s the manufacturing philosophy to increase the production efficiency by grouping a variety of parts having similarities of shape, dimension, and/or process route. ❧It justifies batch production by capitalizing on design and/or manufacturing similarities among components parts.
- 3. Role of GT in CAD/CAM ❧ For closer dimensional tolerances ❧ More economical in higher accuracy ❧ Increased variety of materials , by manufacturing needs. ❧ Lowering scrap rates
- 4. Important Elements of CAD/CAM Integration ❧ It provides a common data base for effective integration of CAD & CAM for successful implementation of CIM ❧ GT provides a common language for users ❧ It gives a information about Design, Manufacturing Attributes, Processes & Capabilities
- 6. Part Families ❧ A part family is a collection of parts which are similar in geometric shape and size or processing steps are required in their manufacture. ❧ It may be a similar in their Design, Manufacturing characteristics are grouped and referred as Design part family & Manufacturing part family ❧ The characteristics used are known as Attributes
- 10. METHODS FOR PART FAMILY FORMATION 1.Visual inspection 2. part classification & Coding Methods 3.production flow analysis
- 11. 1.Visual inspection ❧This is a simplest & least expensive method ❧Here all are arranged in a similar groups
- 15. 2. Part classification & Coding Methods ❧ Coding is systematic process by establishing an alpha- numeric value for parts based on selected part features. ❧ Classification is the grouping of parts based on code values. ❧ Here parts are identified , listed and assigned as per the code numbers both in Designing & Manufacturing.
- 16. Design & Manufacturing Attributes 1.System based on Part Design Attributes 2.System based on Manufacturing Attributes 3.System based on Both Design & Manufacturing Attributes
- 18. Coding System Structure ❧A Group Technology is a string of characteristics capturing information's about an item. ❧A part coding scheme consists of a sequence of symbols that identify the part’s Design / Manufacturing attributes
- 19. Types of Basic Code Structures ❧1. Hierarchical codes (Mono codes or tree structure) ❧2. Attributes codes (Poly code or chain type structure) ❧3. Decision tree codes (hybrid code or mixed codes)
- 20. Hierarchical codes ❧The interpretation of each successive symbols depends on the value of the preceding symbols ❧Each symbols amplifies the information contained in the preceding digit, so that the digits in the symbols cannot be interrupt alone. ❧The structure is like a tree.