Rev. 09/06/01SJSU Bus David Bentley1 Chapter 6 – Process Selection and Facility Layout Process types and selection, automation, layout types, line balancing

Rev. 11/20/01SJSU Bus David Bentley2 Process Selection Make or buy analysis (See pp ) Q BEP = FC / (p – v) Process types (“type of operations”) Project Job [Batch] Repetitive Continuous flow Volume, mix, flexibility considerations

Rev. 11/21/02SJSU Bus David Bentley3 Why Automate?

Rev. 05/13/02SJSU Bus David Bentley4 Why Automate? 1. Reduce or eliminate labor cost?? 2. Apply only to high volume operations?? 3. Keep up with the other CEOs at the Rotary Club?? 4. See the ads and say: “Wow, I’ve got to have one of those!”??

Rev. 09/06/01SJSU Bus David Bentley5 Why Automate? 5. Quality Assures consistency, low variability 6. Rapid change Shortens setups and changeovers Reduces time to turnaround prototypes 7. Lower tooling cost Eliminates specialized tools and dies 8. Reduced labor cost

Rev. 09/06/01SJSU Bus David Bentley6 Automation Concepts - 1 Product design CADD – computer aided drawing and drafting CAD – computer aided design Process design CAPP – computer aided process planning Machine control NC – numerical control CNC – computerized numerical control DNC – direct numerical control FMS – flexible manufacturing system CAM – computer aided manufacturing

Rev. 09/06/01SJSU Bus David Bentley7 Automation Concepts - 2 Production scheduling CAS – computer aided scheduling Service CAI – computer aided instruction Warehousing AS/RS – automated storage and retrieval systems

Rev.11/21/02SJSU Bus David Bentley8 Automation Concepts - 3 Robotics Heavy use in auto industry Described in terms of number of axes of motion (up to 6) Arm sweep Shoulder swivel Elbow extension Pitch (wrist) Yaw (wrist) Roll (wrist)

Rev.05/13/02SJSU Bus David Bentley9 Automation Concepts – 4 CIM – computer integrated manufacturing Integrates all the preceding concepts MAP – manufacturing automation protocol Major development in U.S. auto industry

Rev. 09/06/01SJSU Bus David Bentley10 Line Balancing Definitions Line balancing Balance work among production lines, or Balance tasks among workstations on 1 line Cycle time Materials Management: time from beginning of first operation until completion of last operation, or Industrial Engineering: time between completion of 2 units of product, or Line Balancing: Maximum time allowed at each workstation

Rev. 12/03/03SJSU Bus David Bentley11 Line Balancing Tools Cycle time calculation Output capacity ( OC = OT / CT ) Where OT = Operating Time per day, CT = Cycle Time Cycle time ( CT = OT/D ) Where D = Desired output rate Precedence diagrams Similar to network diagram Measures of effectiveness Balance delay (% of idle time) Efficiency

Rev. 09/06/01SJSU Bus David Bentley12 Layout Types Fixed-Position Process or Functional Product Cellular Mixed

Rev. 11/21/02SJSU Bus David Bentley13 Fixed-Position Product is in a fixed position (e.g., airframe, ship, building, highway, etc.) Resources (people, machines, material) come to the product Requires complex scheduling of resources High space requirements to accommodate resource movement Usually associated with the Project environment

Rev. 11/21/02SJSU Bus David Bentley14 Process or Functional Groups similar resources together by the function or process performed Machine examples are: milling machines, lathes, routers, grinders People examples are: Invoicing, Accounts Payable, Payroll Processing Many crossed paths, high space requirements Easy to supervise, train, etc. Usually associated with the Job and sometimes the Batch environments

Rev. 12/05/02SJSU Bus David Bentley15 Product Resources are arranged to follow the flow of the product Examples are: auto assembly, steel production, bottling, etc. Often called production lines or assembly lines May be straight line, U-shaped, snake Provides for very little WIP storage Usually associated with Repetitive and Continuous Flow environments

Rev.11/21/02SJSU Bus David Bentley16 Cellular Resources (labor and equipment) arranged in small groups (cells) Have responsibility for output, quality, maintenance, etc. for a grouping of tasks or parts Referred to as “teams” in services sector Teamwork essential May be straight line or U-shaped; no WIP storage Most recently developed layout Usually associated with Repetitive environment

Rev. 11/21/02SJSU Bus David Bentley17 Mixed Two or more layout types in 1 facility Examples Manufacturing: burn-in or baking Restaurants (kitchen is functional, buffet line is product, menu ordering is fixed-position) More difficult to plan More costly to equip More troublesome to maintain

Rev. 11/21/02SJSU Bus David Bentley18 U-Shaped Advantages Staff flexibility and balance Teamwork Immediate rework Accessibility Work and tool distribution Linking with other U-shaped layouts