MENG 447 Manufacturing Systems Automation Chapter 1*

1. MENG 447Manufacturing Systems AutomationChapter 1* *Based on information from Groover, 2001. Automation, Production Systems, and Computer-Integrated Manufacturing. Dr. Lotfi K. Gaafar

2. The Production System Manufacturing support systems Manufacturing facilities: factory, equipment Dr. Lotfi K. Gaafar

3. Discrete Manufacturing 1 Dr. Lotfi K. Gaafar

4. Discrete Manufacturing 1 Job shop Batch Production Material Handling Complexity Variety Mass Production Quantity Automation Specialization Skills Dr. Lotfi K. Gaafar

5. Mass production* Automation easily justified Objectives: (1) reduce operation cycle time, (2) increase system reliability Line is rarely changed - setup time not critical Inflexible: not suitable for products with many options or limited production runs Discrete Manufacturing 1 * Check the textbook on the two types: quantity and flow line Dr. Lotfi K. Gaafar

6. Job shop production Products produced in small volume Automation difficult to justify unless products are too complex to be produced manually Objectives: (1) reduce setup time, (2) reduce processing time, (3) reduce WIP Most flexible of production strategies Discrete Manufacturing 1 Dr. Lotfi K. Gaafar

7. Batch production Products produced in batches, lots or groups Trade-off between job shop and mass production Single setup for each batch Increase batch size, but increase in waiting time, WIP and inventory result Objectives are same as job shop Discrete Manufacturing 1 Dr. Lotfi K. Gaafar

8. Facility Layout 2 Four types of layouts: Fixed Position: suitable for large products Process: suitable for job shop Cellular: suitable when products are similar in batch production and sometimes in job shop Product flow: suitable for mass production Dr. Lotfi K. Gaafar

9. Fixed position layout Product must remain stationary throughout production sequence Machines are brought to the product Higher expense due to robustness and accuracy of equipment Facility Layout 2 Dr. Lotfi K. Gaafar

10. Process layout For small, discrete-parts manufacturing Machines are grouped into departments according to type of operation Advantages: work schedule more flexible Disadvantages: WIP is large (cost in inventory and storage space), high material handling cost, larger batches are made than are required (to justify setup), difficulty in maintaining control of parts, highest skill level required from operators Facility Layout 2 Dr. Lotfi K. Gaafar

11. Group technology (cellular) layout Several different types of machines are grouped together to form a cell - each cell is designed to produce a family of parts Suitable for small to mid-volume production of parts Advantages: setup time is reduced, lead time is reduced, WIP is reduced, finished inventory is reduced, improved quality (group of workers responsible for a cell) Disadvantages: parts must be grouped into families, layout is less flexible than process layout, batches from same family cannot be run simultaneously, higher skill level required from operators Facility Layout 2 Dr. Lotfi K. Gaafar

12.     Product flow layout Suited for high volume production Advantages: minimized material handling, easy to automate material handling, less WIP, easier to control Disadvantages: inefficient to alter the sequence of operations, breakdown on one machine can stop the entire line Facility Layout 2 Dr. Lotfi K. Gaafar

13. Facility Layout/Production Level 2 Dr. Lotfi K. Gaafar

14. Manufacturing Support Systems 3 Dr. Lotfi K. Gaafar

15. Machines Transfer lines Assembly Material Handling Inspection (coordinate measuring machines, CMM) Automated Manufacturing Systems 3 Dr. Lotfi K. Gaafar

16. Fixed Automation (transfer lines) Hard automation, automation for mass production Produces large numbers of nearly identical parts High initial investment for custom engineered equipment Product design must be stable over its life Advantages: equipment fine tuned to application - decreased cycle time, infrequent setups, automated material handling - fast and efficient movement of parts, very little WIP Disadvantage: inflexible Types of Automation 3 Dr. Lotfi K. Gaafar

17. Programmable Automation (NC, CNC, robots- e.g., chess) Sequence controlled by a program High investment in general purpose equipment Lower production rates Flexibility to deal with variation Suitable for batch production Smaller volumes (than fixed) of many different parts More flexible than fixed automation Major disadvantage: setup prior to each new part Large batch size (due to setups) Speed sacrificed for flexibility Types of Automation 3 Dr. Lotfi K. Gaafar

18. Flexible Automation (e.g., piston head) Extension of programmable automation No time lost for change over High investment in custom-engineered systems Production of product mix Flexibility to deal with design variations Low to medium quantities Compromise between fixed and programmable automation in speed and flexibility Advantage: programming and setup performed off-line More expensive - size and tool change capabilities Small batch sizes are justified - reduced WIP and lead time Typical parts are expensive, large and require some complex machining Types of Automation 4 Dr. Lotfi K. Gaafar

19. Types of Automation 4 Dr. Lotfi K. Gaafar

20. Increase production rate eliminate portions of process that directly increase production time: machine processing time, handling time, setup times (SMED) Remove humans from hazardous environments exposure to chemicals, fumes, temperature or radiation robotic applications: L/UL furnaces, spray painting, welding Remove humans from processes that require extremely clean environments: e.g., semiconductors, drugs Reduce number of defective products Reduce direct labor one worker monitors a larger number of machines Reasons for Automating 4 Dr. Lotfi K. Gaafar

21. Reduce work-in-process parts being processed, part waiting to be processed large WIP: longer time to fill orders, more storage space, value of unfinished goods that could be invested elsewhere reduced WIP: better control and scheduling Reduce manufacturing lead time processing time, setup time, waiting time setup time: flexible automation, common fixtures and tooling processing time: combining or eliminating operations, increase speed (work measurement principles) Increase quality repeatable operations through every cycle - tighter control limits, easier detection when process is out of control status of manufacturing operations Reasons for Automating 4 Dr. Lotfi K. Gaafar

22. Increase productivity Reduce labor cost Address labor shortages Reduce or eliminate routine manual and clerical tasks Health and Safety May be the only option Stay up-to-date (avoid cost of catching up) Reasons for Automating 5 Dr. Lotfi K. Gaafar

23. Strengths of Humans Sense unexpected stimuli Develop new solutions to problems Cope with abstract problems Adapt to change Generalize from observations Learn from experience Make difficult decisions based on incomplete data Manual Labor in Automated Systems 5 Dr. Lotfi K. Gaafar

24. Strengths of (computer-based) machines Perform repetitive tasks consistently Store large amounts of data Retrieve data from memory reliably Perform multiple tasks simultaneously Apply high forces and power Perform computations quickly Manual Labor in Automated Systems 5 Dr. Lotfi K. Gaafar

25. Manual Labor in Automated Systems 5 • Even if all of the manufacturing systems in the factory are automated, there will still be a need for the following kinds of work to be performed: • Equipment maintenance. Maintain and repair, improve the reliability, of automated systems. • Programming and computer operation. • Engineering project work. Upgrades, design tooling, continuous improvement. • Plant management. Dr. Lotfi K. Gaafar

26. AUTOMATION PRINCIPLES AND STRATEGIES 6 USA Principle: 1. Understand the existing process 2. Simplify the process 3. Automate the process (if needed) Dr. Lotfi K. Gaafar

27. AUTOMATION PRINCIPLES AND STRATEGIES 6 Ten Strategies for Automation 1. Specialization of operations. 2. Combined operations. 3. Simultaneous operations. 4. Integration of operations. 5. Increased flexibility. 6. Improved material handling and storage. 7. On line inspection. 8. Process control and optimization. 9. Plant operations control. 10. Computer integrated manufacturing (CIM). Dr. Lotfi K. Gaafar

28. AUTOMATION PRINCIPLES AND STRATEGIES 6 Dr. Lotfi K. Gaafar