19-10-2012, 03:54 PM
Material Requirements Planning
5 MRP.ppt (Size: 175.5 KB / Downloads: 142)
The simultaneous probability problem
When components are ordered independently with an order point system, the probability that all will be in stock at the same time is much lower than the probabilities for individual components
Product structure
Bills of material are hierarchical with distinct levels
To compute requirements, always proceed down bill of materials, processing all requirements at one level before starting another
Recurrence of requirements within the planning horizon
The same item may be required for several different lots within the planning horizon – always process one lot entirely, level by level, before starting the next.
Regeneration vs. net change
Regeneration
Complete replanning of requirements and update of inventory status for all items
High data processing efficiency
Usually initiated by weekly update of master schedule
Net change
Daily update based on inventory transactions
More responsive to changing conditions
Requires more discipline in file maintenance