Learn in the textbookProduction Management Methods and Systems
DefinitionMRP (material requirements planning, 資材所要量計画) is a method that calculates the quantities of parts and materials needed and when to order them, based on the product's production plan and bill of materials.
ExplanationA bill of materials is a table that shows, in levels, which parts one unit of a product uses and how many of each. MRP multiplies the number of products needed by the quantities in the bill of materials to get the gross requirement, then subtracts usable stock to find the net requirement. It then counts back by the lead time needed for procurement or processing to set when to order or start work.
AnalogySay you decide to make boxed lunches for 30 people on Friday. You work out the rice and fillings from a one-serving ingredient list, subtract what is already in the fridge, and pick the order date from how many days delivery takes.
Memory hookThe letters stand for Material, Requirements, and Planning, and the Japanese name is a direct translation of those words.