DRP Stability Rules

Definition

Stability rules in distribution requirements planning (DRP) that determine the conditions between the individual DRP horizons , and which activities are allowed during them.

Use

DRP stability rules apply to location products. You define the stability rules in Customizing under Define Stability Rule for DRP Horizons and then assign them to location products in the location product master data on the SPP DRP tab page. The system applies the stability rules at the entry location.

For more information, see the Implementation Guide (IMG) for Advanced Planning and Optimization under Start of the navigation path Supply Chain Planning Next navigation step Service Parts Planning (SPP) Distribution Requirements Planning (DRP) Define Stability Rule for DRP Horizons End of the navigation path .

Note Note

You cannot use the stability rules for location products that you plan in the reorder point based planning mode .

End of the note.

Structure

A DRP stability rule consists of several sub rules, a procedure that the system follows when applying the rule, and an indicator that controls the planning in certain cases.

Subrules

A DRP stability rule is divided into the following rules:

Stability rule for limited freeze horizon (expedite)

This rule is valid in between the freeze horizon and the limited freeze horizon. The system applies this rule if a shortage occurs. DRP checks whether it can expedite a planned goods receipt that lies in the future to get rid of the shortage.
Stability rule for limited freeze horizon (postpone)

This rule is valid in between the freeze horizon and the limited freeze horizon. The system applies this rule if there is an excess. In this case, DRP checks to see if it can postpone a planned goods receipt to eliminate the excess.
Stability rule for plan submission horizon (expedite)

This rule is valid in between the limited freeze horizon and the plan submission horizon. The system applies this rule if there is a shortage. In this case, Distribution Requirements Planning (DRP) checks to see if it can expedite a planned goods receipt to eliminate the shortage.
Stability rule for plan submission horizon (postpone)

This rule is valid in between the limited freeze horizon and the plan submission horizon. The system applies this rule if there is an excess. In this case, DRP checks to see if it can postpone a planned goods receipt to eliminate the excess.

Limited Freeze Horizon: Procedures for Order Scheduling

In the limited freeze horizon the system applies the DRP stability rules according to one of the following procedures Procedures for Order Scheduling :

If you choose Single order , the system checks the entire shortage amount within the limited freeze horizon (in the case of a shortage). The system then creates exactly one planned goods receipt of the entire shortage amount, or extends the amount of an available planned goods receipt by the shortage amount.

In the case of an excess, the system reduces an order by the excess amount. If the order quantity is smaller than the excess quantity, the system reduces the amount of the next order, and so on.
If you choose Each Individual period , the system extends the order quantity of a period by the shortage quantity (in the case of a shortage quantity within a limited freeze horizon). In the case of an excess, the system reduces the order quantity within a period by the excess amount. If the order quantity is smaller than the excess quantity, the system deletes the order quantity and reduces the amount of the next order, and so on.
If you choose No change of Order Quantity , the system does not change the order quantity even is there is an excess or a shortage.

Limited Freeze Horizon: Indicator for Replanning

The indicator Schedule Orders According to All Demand only applies to the limited freeze horizon. The system only considers the indicator if you choose the procedure Each Individual period . If you set the indicator and there is an excess or a shortage, the system reschedules the entire DRP planning horizon. In doing so it begins with the period for which there is an excess or a shortage. When recalculating the DRP planning horizon the system the system does not consider stability rules.