mgmt 339 resource planning

Independent-demand Items

Independent-demand Items

items that are ready to be sold or used

Dependent-demand Items

components of finished products

Independent demand items - consistent demand (always needed)

Independent demand fairly stable once allowances are made for seasonal variations

Dependent demand items - low demand (lumpy demand):

Some components might be used for only one time or once a while(e.g., once every eight or nine weeks). Large quantities are used at specific points in time with little or no usage at other times.

Material Requirements Planning

A computer-based information system developed specifically to help manufacturers manage dependent demand inventory and schedule replenishment orders.

MRP translates master schedule requirements for end items into

time-phased requirements for subassemblies, components, and raw materials

MRP works background from

the due date to determine when and how much to order.

Requirements for end items

generate requirements for low-level components

MRP begins with a schedule for finished goods that is converted into a schedule of requirements for

the subassemblies, component parts, and raw materials needed to produce the finished items.

Final Product

Finished chair = independent demand

Dependent demand items:

the demand for these items is dependent on the production of final products.

Master Production Schedule (MPS)

The master schedule (or master production schedule) states which enditems are to be produced, when they are needed, and in what quantities

the MPS is the part of the material requirements plan that details how many end items

will be produced within specified periods of time.

the MPS breaks the

sales and operations plan into specific product schedules

Cumulative lead time

The sum of the lead times that sequential phases of a process require,from ordering of parts or raw materials to completion of final assembly.

It is important that the master schedule covers the

cumulative lead time necessary to produce the end items

Bill of materials

is a listing of all of the raw materials, parts, subassemblies, and assemblies needed to produce one unit of a product

BOM is a record of all the components of an item,

the parent-component relationships, and the usage quantities derived from engineering and process designs.

the BOM shows the quantity of each item

needed to complete one unit of its parent item

Product Structure Tree

A visual illustration of the requirements in a bill of materials,where all components are listed by levels.

Component

an item that goes through one or more operations to be transformed into or become part of one or more parents. All items except item A are components because they are needed to make a parent.

Parent

Any product that is manufactured from one or more components. Items A, B, C, and H are parents because they all have at least one component.

end item

The final product sold to a customer. (e.g., completed ladder-back chair)

intermediate item

an item that has at least one parent and at least one component.

Subassembly

An intermediate item that is assembled from more than one component.

Purchased item

An item that has one or more parents but no components because it comes from a supplier.

Inventory Records

A record that shows an item's lot-size policy, lead time, and various time-phased data

Information on the status of each item by time period, also called time buckets

This includes: 1. Gross requirements 2. Scheduled receipts 3. Projected on-hand inventory 4. Planned receipts 5. Planned order release

Gross requirements

The total demand derived from all parent production plans.

scheduled receipts

Orders that have been placed but not yet completed. E.g., being processed by a supplier, being transported to the purchaser, or being inspected by the purchaser's receiving department.

projected on-hand inventory

an estimate of the amount of inventory available each week after gross requirements have been satisfied.

planned receipts

Orders that are not yet released to the shop or the supplier. Still at the planning stage and can still change

Planned order release

An indication of when an order for a specific quantity of an item is to be issued.

Food catering service

end item - meals for large number of people bom - quantities of the ingredients for each recipe on the menu