Lean Operations
McGraw-Hill/Irwin Copyright © 2012 by The McGraw-Hill Companies, Inc. All rights reserved.
You should be able to:1. Explain what is meant by the term lean operations system2. List each of the goals of a lean system and explain its
importance3. List and briefly describe the building blocks of lean4. List the benefits of a lean system5. Outline the considerations important in converting a
traditional mode of operations to a lean system6. Point out some of the obstacles that might be encountered
when converting to a lean system7. Describe value stream mapping
Instructor Slides 14-2
Lean operation
A flexible system of operation that uses considerably less resources than a traditional system Tend to achieve
Greater productivity
Lower costs
Shorter cycle times
Higher quality
Instructor Slides 14-3
The ultimate goal:
Achieve a system that matches supply to customer demand; supply is synchronized to meet customer demand in a smooth uninterrupted flow
A balanced system One that achieves a smooth, rapid flow of materials and/or
work through the system
Instructor Slides 14-4
Instructor Slides 14-5
The degree to which lean’s ultimate goal is achieved depends upon how well its supporting goals are achieved:1. Eliminate disruptions
2. Make the system flexible
3. Eliminate waste, especially excess inventory
Instructor Slides 14-6
Five personnel/organizational elements that are important for lean systems: Workers as assets
Cross-trained workers
Continuous improvement
Cost accounting
Leadership/project management
Instructor Slides 14-7
Seven elements of manufacturing planning and control (MPC) are particularly important for lean system:1. Level loading
2. Pull systems
3. Visual systems
4. Limited work-in-process (WIP)
5. Close vendor relationships
6. Reduced transaction processing
7. Preventive maintenance and housekeeping
Instructor Slides 14-8
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Instructor Slides 14-9
Preventive maintenance
Maintaining equipment in good operating condition and replacing parts that have a tendency to fail before they actually do fail
Housekeeping Maintaining a workplace that is clean and free of
unnecessary materials
Instructor Slides 14-10
1. Make sure top management is committed and that they know what will be required
2. Decide which parts will need the most effort to convert
3. Obtain support and cooperation of workers
4. Begin by trying to reduce setup times while maintaining the current system
5. Gradually convert operations, begin at the end and work backwards
6. Convert suppliers to JIT
7. Prepare for obstacles
Instructor Slides 14-11
1. Management may not be fully committed or willing to devote the necessary resources to conversion
2. Workers/management may not be cooperative
3. It can be difficult to change the organizational culture to one consistent with the lean philosophy
4. Suppliers may resist
Instructor Slides 14-12
In service the focus is often on the time needed to perform the service because speed is often the order winner
Lean benefits can be achieved in the following ways: Eliminate disruptions
Make system flexible
Reduce setup and lead times
Eliminate waste
Minimize WIP
Simplify the process
Instructor Slides 14-13
JIT II:
A supplier representative works right in the company’s plant, making sure there is an appropriate supply on hand
It is often referred to as vendor managed inventory (VMI)
Instructor Slides 14-14
Be careful to study the requirements and benefits of lean systems before making a decision to convert operations Evaluate strengths and weaknesses of current operations
The decision to convert can be sequential
Weigh the pros and cons of a lean approach to inventories
Supplier management is critical to a lean operation
Instructor Slides 14-15