MRP Is a Parts Planning and Tracking System
MRP is a time-phased material planning system. This means parts. What part do we need? When do we need it? Where? Can we buy it or will be build it? MRP is not concerned with finite capacity or collecting labor data.
An MRP planner is not scheduling work for the shop to do, he/she is planning the creation of part numbers. This is a shift in the paradigm of most planners who have been scheduling activities instead of parts.
When the MRP system was first implemented, the company hosted a conference of all other companies in the corporation. In the group discussion that I led, there were two engineers. One of them asked a question and then stated that he was an APICS member and certified, CPIM. I was impressed and envious, because I had just started my own certification process with two tests passed. I proceeded to answer his question, and after several minutes the other engineer stopped us and said that he had heard what we were saying, but understood nothing that we were talking about! This was the first time that I realized that I had acquired a new jargon that was unique to operating the company using MRP. These are some of the terms that I would list for the class so we could agree on the definition within the context of the company work environment.
• Create: transaction stores a firm planned work order
in the system.
• Firm plan: work order that can accept part reserva
tions, that the planner can alter.
• Release: transaction changes planned or firm planned
work order to released work order. At this point the
• Requirement: a need for a part. All of the component
parts that make up an assembly are required to be
installed. This data comes from the BOM or from a
write-in by the planner.
• Reservation: an electronic tag put on a part by a plan
ner so that the part can be issued only to a specific
work order. The computer system will not change a
• Allocation: an electronic tag, like a reservation, made
by the computer system. Allocations may be changed
by the computer system as conditions change.
Note that the preceding terms are specific to the par
ticular system that the company was using. Most MRP
systems have a similar function, but may be called by
• Routing: data that the engineer inputs to the com
puter system, consisting of the work steps necessary
to build up a part number. If work is accomplished in
multiple work centers, the routing is also a map of
path that the work order will follow through the plant.
• Work order: a package of documents that authorize
technicians to perform work. In most software pack
ages this is called the manufacturing order.
• MRP (mrp): material requirements planning, a series
of computer programs that operate as a system to
plan, control, and track inventory and production.
• MRP (MRP, MRP II): manufacturing resource plan
ning, a manufacturing planning and control system that is used by management to make operational decisions, one virtual database.
• BOM: bill of material, a list of component parts required to build up an assembly, and all the associated data necessary for MRP to plan and control the creation of that assembly.
To Be Continued
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