• Begun around 1960 as computerized approach to purchasing and production scheduling.
• Joseph Orlicky, Oliver Wight, and others.
• Prior to MRP, production of every part and end item was triggered by the inventory falling below a given level (reorder point).
• APICS launched “MRP Crusade” in 1972 to promote MRP.
• Independent Demand — finished products
• Dependent Demand — components
It makes no sense to independently forecast dependent demands.
1. Known deterministic demands.
2. Fixed, known production leadtimes.
3. In actual practice, lead times are related to the level of WIP.
Flow Time = WIP / Throughput Rate (Little’s Law)
Idea is to “back out” demand for components by using leadtimes and bills of
Continue at: http://web.utk.edu/~kkirby/IE515/Ch03.pdf
The text above is owned by the site above referred.
Here is only a small part of the article, for more please follow the link