SAP - Linkage of MPS and MRP

April 11, 2023 Page 1

MRP Overview

MRP Types

Master Production Scheduling is carried out for finished product that manufacturing in-

house

Material Requirement Planning is carried out using current and future sales figures

Consumption-Based Planning uses past consumption data to calculate future requirements Reorder Point Planning Forecast-Based Planning Time-Phased Planning


MRP Overview

Processing Steps

During a planning run, the system performs the following steps

Calculates net requirements Calculates lot size Scheduling Creates order proposals Creates exception messages


MRP – Calculates net requirements

MPS MRP

SR

1. Requirement from sales order passed on to demand management

SO

SO

PlnOrd

R S

2. MPS planning run result as ‘Planned order’ to supply requirement.

SO

SO

PlnOrd

ProOrd

R S

3. Production planner convert planned order to be production order

PlnOrd

SO

SO

A.1 Requirements of components are passed on to MRP

SR

DepReq

DepReq

Safety

Stock

A.5 GR from vendor

R S

DepReq

DepReq

PlnOrd

Stock

Safety Stock

R S

Depreq

A.7 Reservation is eliminated when material is withdrawn for production order

PlnOrdSafety Stock

R S

DepReq

DepReq

PlnOrd

PR

A.3 PR is created (See detail)

Safety Stock

A.6 Reservation is created from production order

R S

Depreq

Reservation Stock

PlnOrdSafety Stock

R S

DepReq

DepReq

PlnOrd

PO

A.4 Buyer convert PR to PO

Safety Stock

R S

PlnOrd

A.2 Procurement Proposal is created from MRP planning run

DepReq

DepReq

Safety Stock


MPS MRP

SO

R SSO PlnOrd

DO Stock5. CS open delivery order for arrange shipment

R SSOSO

PlnOrdStock

6. Post goods issue ref. DO after goods has been shipped

R SPlnOrd

Stock4. Make goods receipt to warehouse when finish produce

SO

SO

ProOrd

R S

From previous page

PlnOrd

SO

SO

MRP – Calculates net requirements


MRP – Calculates lot size

Lot-sizing Procedures

The system calculates the receipt quantity in the lot-size calculation, which is carried out during the procurement quantity calculation. Lot-for-lot order quantity Replenishment to maximum stock level Weekly lot size Monthly lot size

Additional restrictions Minimum lot size (minimum procurement quantity per lot) Rounding value (The procurement quantity must be a multiple of this value)


MRP – Scheduling

Backward Scheduling for External Procurement

For materials that are planned, the requirement dates in the future are known. The materials must be available by these dates. The release date for the purchasing department is calculated during scheduling, that is, the date by which the materials must be ordered so that they are available for the requirements date.

Process FlowThe system starts with the requirements date and then schedules backwards to determine the release date of the purchase requisition (order start date of planned order, which is to be procured externally).


MRP - Scheduling

Backward Scheduling for External Procurement

MRP date3.03.08

MRP date10.03.08

time

Releasedate 23.2.08

Openingdate 20.2.08

GR processingtime 1 day

Planned delivery time7 days

Processing timefor purchasing 1 day

Openingperiod 3 days

Releasedate 16.2.08

Openingdate 13.2.08

GR processingtime 1 day

Planned delivery time7 days

Processing timefor purchasing 1 day

Openingperiod 3 daysToday

20.2.08

Example Material: 14003290GR processing time 1 day Planned delivery time 7 daysProcessing time for purchasing 1 day Opening period 3 days


MRP – Creates order proposals

Order ProposalsThe type of order proposal that is automatically created by the planning rundepends on the material’s procurement type.

•For materials produced in-house, a planned order is automatically created.

•For materials that are externally procured, the MRP controller can decide between a planned order or a purchase requisition.


Reorder LevelThe reorder level (sometimes known as the reorder point) is calculated by adding the safety stock plus the expected average material consumption within the replenishment lead time. When determining the reorder level, you must consider safety stock, previous consumption values or future requirements, and the replenishment lead time.

Safety StockSafety stock must be set at a level that covers both excess material consumption within the replenishment lead time and any additional requirements that may occur because of delivery delays. Therefore, you must consider previous consumption or future requirements, and vendor delivery/production timeliness when determining the safety stock level.

MRP - Reorder Point Planning



PO

PR

Stock

Qty

Reorder Point

Example: Material 14002001 Lead time 7 days Average consumption 20 EA (per lead time) Safety Stock 50% = 10 EA (consumption deviation) Reorder Point = 20 + 10 = 30 EA

Qty

Reorder Point

Stock

PO

Calculates net requirements

Qty

Reorder Point

Stock

Reservation



Example: Material 14002001 Lead time 7 days Average consumption 20 EA (per lead time) Safety Stock 50% = 10 EA (potential deviation) Reorder Point = 20 + 10 = 30 EA

Qty

Reorder Point

Stock

Qty

Reorder Point

Stock

Calculates net requirements

PR

Stock

Qty

Reorder Point

PO

PO



Example: Material 14002001 Lead time 7 days Average consumption 20 EA (per lead time) Safety Stock 50% = 10 EA (potential deviation) Reorder Point = 20 + 10 = 30 EA

Calculates lot sizeLot size: Lot-for-lot order qty

Replenish to maximum stock level

PR 3EA

Stock27 EA

Qty

Reorder PointPR 5EA

PR 23EA

Qty

Reorder Point

Maximum stock level

Stock27 EA

PR 25EA



Reorder point

Safetystock

Stock Lot size

TimeDeliverydate

Replenishmentlead time

Reorder point

Replenishment of stock


Exceptional messagesException messages depend on the transaction being carried out and are meant to inform you of an important or critical event (for example, start date lies in the past, safety stock has been exceeded).

By means of the exception messages, you can easily sort out any materials that you need to reprocess manually. Special search and selection functions are available for this in the evaluations for MRP.

MRP - Creates exception messages


Planning ResultsThe MRP controller has two options for calling up the planning results: MRP list (MD05) Stock/requirements overview (MD04)

MRP – Planning Result

Documents

SAP - Linkage of MPS and MRP