COMPUTER INTEGRATED MANUFACTURING Unit – I / Topic :8 ME 6703/ CIMS / UNIT- 1

TOPICS TO BE DISCUSSED LEAN PRODUCTION ME 6703/ CIMS / UNIT- 1

DEFINITION It can be defined as an application of mass production in which workers and cells are made more flexible and efficient by adopting methods that reduce waste in all forms. A set of tools and methodologies that aims for continuous elimination of all wastes in the production process. TPS - Toyota ME 6703/ CIMS / UNIT- 1

Objectives of Lean Production Defects & Wastage To reduce defects and unnecessary physical wastage- excess use of raw material inputs, preventable defects, costs associated with reprocessing defective items and unnecessary product characteristics. Cycle times To reduce manufacturing lead times and production cycle times by reducing waiting times between processing stages, process preparation times, product conversion times. Inventory levels Labour Productivity Reducing the idle time of workers, ensuring that when workers are working, effort as productively as possible. Utilization of equipment & space Use equipment and manufacturing space more effectively by eliminating bottlenecks and increase the rate of production through existing equipment, reduce the machine downtime. Flexibility – Minimum change over time and change over cost. Output ME 6703/ CIMS / UNIT- 1

Key Principles of Lean Manufacturing Recognition of waste – what does not create value from the customer(material transport b/w workstations). Standard Processes – sequence, timing, outcome of all actions by workers(workers perform their tasks). Continuous flow – production flow free of bottlenecks, interruption, detours, backflows/waiting – successfully implemented cycle time will be reduced upto 90%. Pull Production – JIT, what is needed, when is needed . Quality at the source – Defects to be eliminated at the source, inspection @ in-line production process. Continuous improvement – High level of worker – continually removing layers of waste as they are uncovered. ME 6703/ CIMS / UNIT- 1

ACTIVITY List out the Tamil words. Tell the correct order of “MEI EZHUTHUKAL”. ME 6703/ CIMS / UNIT- 1

ME 6703/ CIMS / UNIT- 1

Lean Manufacturing Concepts Value Creation & Waste – customer requires and willing to pay for. Value added activities (5%) – transforms materials into exact product that customer requires. Non-Value added activities(60%) – which aren’t required for transforming materials into product that customer requires. Necessary non-value added activities(35%) – High levels of inventory maybe required as buffer stock. Main kind of waste Over production – Unnecessarily producing more than demanded. Defects – Paperwork, Provision of incorrect information about the product, late delivery, production to incorrect specifications. Inventory Transportation – movements of materials that does not add any value to the product, moving b/w workstations. Waiting – idle time for workers or machines due to bottlenecks or inefficient production flow on the factory floor. Motion - Unwanted motions which diverts them from processing work. Correction – rework of the component. Over processing- More processing then customer requirements. Knowledge disconnection – Information isn’t available where/when it is needed. ME 6703/ CIMS / UNIT- 1

Pull production – what is needed, when is needed Continuous Flow – one piece flow/small batch no waiting time b/w production stages. Continuous Improvement / Kaizen – Systematic process for ensuring continuous improvement.(NVA to be eliminated) Worker Improvement – Ideas to eliminate NVA originate with workers involved in those processes. ME 6703/ CIMS / UNIT- 1

MCQ’S ME 6703/ CIMS / UNIT- 1 1)Lean manufacturing is a : a)Fad. b)Method for reducing labor. C)Way to improve customer value d)Efficiency improvement technique. 2)Customer Value is defined as: a)Cost.  b)Delivery. c)Reliability. d)Response. e)All of the above. 3)Cycle time is: a)Elapsed time from customer order to payment  b)Reduced to eliminate jobs. c)The amount of time the machine runs. d)Improved by larger lot sizes. 4)Cycle-time-efficiency is: a)Improved by increasing utilization.  b)The machine cycle divided by number of pieces produced. c)Increased by larger lot size. d)Value-added time over elapsed time. 5)One-piece-flow means: a)Batch.  b)Larger lot sizes. c)One piece moves to the next operation. ME 6703/ CIMS / UNIT- 1

ANSWERS ME 6703/ CIMS / UNIT- 1 1)Lean manufacturing is a : a)Fad. b)Method for reducing labor. C)Way to improve customer value d)Efficiency improvement technique. 2)Customer Value is defined as: a)Cost.  b)Delivery. c)Reliability. d)Response. e)All of the above. 3)Cycle time is: a)Elapsed time from customer order to payment  b)Reduced to eliminate jobs. c)The amount of time the machine runs. d)Improved by larger lot sizes. 4)Cycle-time-efficiency is: a)Improved by increasing utilization.  b)The machine cycle divided by number of pieces produced. c)Increased by larger lot size. d)Value-added time over elapsed time. 5)One-piece-flow means: a)Batch.  b)Larger lot sizes. c)One piece moves to the next operation. ME 6703/ CIMS / UNIT- 1

ME 6703/ CIMS / UNIT- 1