Lecture 5: Aggregate planning, JIT, Lean, TPS Flashcards
What are swith over times?
This is the time it takes to change production from one product to another
What are the steps in planning?
- Set goals and objectives
- Determining steps to achieve goals
- Setting start and completion dates
- Assign responsibility
Name and describe the three planning horizons
- Strategic: long-term plans of multiple years made by top executives
- Tactical: Intermediate plans of 3 to 18 months. Made by operations manager
- Operational: short-term plans from today to 3 months. Made by operations management or supervisors
What is aggregate planning?
Aggregate planning is focused on providing quality and timing of production for the intermediate future. It comines production and involves capacity and demand variables
Name the four aggregate planning goals?
- Meet demand
- Meet inventory policy
- Use capacity efficiently
- Minimize costs
What are the aggregate planning strategies?
- Capacity options - change capacity
- Demand options - Change demand
What is the difference between a level and chase strategy?
A level strategy means the production rate is constant
A chase strategy means the production rate equals demand
What is Just-in-time?
Its a strategy where supplies are pulled through the system to arrive where they are needed when they are needed
It strives for continuous improvement
How is aggregate planning used when providing services?
Its an attempt to allocate fixed capacity of a service to maximize profit/yield
Name four side-features of just-in-time?
- Attack waste
- Exposes problems and bottlenecks caused by variability
- Achieve streamlined production
- Maintain respect for all workers
What is lean production?
Lean production means customer is supplied with exactly what he wants, when he wants it, without waste, through continuous improvement
Name the seven wastes of JIT?
- Overproduction
- Inefficient processing
- Waiting
- Inventory
- Transportation
- Unnecessary motion
- Product defects
Why does variability occur?
- Products are not up to standards
- Engineering drawings are inaccurate
- Production before drawing is completed
- Unknown customer demands
What are push systems?
Systems where material is pushed into downstream workstations whether its needed or not
How can you reduce setup/changeover times?
- Modular product design
- Group technology
- Flexible production automation
- Shigeo shingo
What are pull systems?
Systems where material is pulled into a workstation just as it is needed.
Name the 5 results of JIT?
- Reduction in queue and delay
- Quality improvement
- Cost reduction
- Variability reductions
- Rework reduction
What is shigeo shingo?
This is a concept of how companies can minimize setup times and contains:
1. Distinguish between external and internal setup times.
2. Make internal setup time external
3. Reduce internal setup time
What is external setup time?
This is the required time to setup a batch that can be done while production is still running
What are transformation systems?
These systems revolve around planning and involves the timing of operations using JIT principles.
Should companies produce large or small lot sizes?
Companies should produce in small lot sizes to be able to better meet customer demand. BUT, this can only be done when setup times are small
What is kanban?
This authorized production from downstream operations. Often used with fixed-sized containers
What are five potential problems of implementing JIT?
- applicable primarily to repetitive operations
- Requires discipline
- Based on trust and cooperation
- PRoblem dealing with uncertainty
- Requires change of philosophy.
