Supply Chain Constraint-Based Planning

Constraint-based planning and scheduling is an approach for balancing material and plant resources while meeting customer demand. It takes into account constraints at the enterprise and plant levels. Material and capacity constraints are considered simultaneously. Capacity constraints include factory, distribution, and transportation resources. This complete picture of the problem provides instant and global visibility to the effects of planning and scheduling decisions throughout the supply chain.

There are two types of constraint-based planning--with and without optimization. This section first describes constraint types that are applicable to both types, and then describes constraint-based planning without optimization. Constraint-based planning with optimization is described in Optimization.

You cannot plan repetitive items in constrained plans.

Constraint Types

You can define constraints for materials and resources in your plan. You will also be able to specify the level of importance of these constraints depending on your business needs and the planning horizon. You can generate plans using the following scenarios for each planning bucket type (days, weeks, periods):

See Defining Plans for information on defining the relative importance of constraints.

The following table gives you the information you need to run a constraint-based plan:

Constraint Type Includes
Items BOM effectivities (process effectivity), ECOs, alternate BOMs, substitute components, by-products, safety stocks, order modifiers, supplier-specific order modifiers, supplier-specific lead-times, pegging restrictions
Manufacturing Resources Routing effectivities, alternate routings, alternate resources, resource capacities, line rates, workday calendar
Transportation Resources Carrier capacities, shipment and delivery calendars
Sourcng Constraints Sourcing effectivities, sourcing ranks, allocation percentages, supplier capacity
Suppliers Supplier capacity, supplier rank, supplier calendar, flex fences, supplier order modifier
Dem Dands Sales orders/forecasts, demand priority, demand priority rules

Items

Item Definition

General Planning tab, Source Organization field: Do not set the value of this field to the same organization in which you are setting the item attributes.

You set item attributes for process manufacturing supply tolerances as item attributes. These tolerances instruct the planning engine not to exactly match supply to demand at all times through the planning horizon. See Supply Tolerances.

The item attribute Create Supply only applies to end item substitution. It specifies whether to create supply at the current revision of the item or at a higher revision of the item. It does not control whether or not the planning engine creates planned orders for the item; for this, use item attribute MRP Planning Type.

Use the Item Attributes Mass Maintenance form to update the same item attributes for multiple items..

Bills of Material

You can set effective dates for BOMs. Similarly, you can set effective dates for process effectivity (this is for Oracle OPM only). You can specify effectivities in the form of effective dates, use ups, model/unit numbers. For more information, see Effective Date Fields, Oracle Bill of Materials User's Guide and Primary and Alternate Bills of Material, Oracle Bills of material User's Guide

Note: Effectivity can be set not only at the date level, but also at the unit number level.

The planning engine uses the yield percentage that is effective on the pegging demand date. Because of constraints, the planning engine could later schedule the component to be used on a date that has different yield percentage in the bill of material; however, the planning engine continues to use the yield from the pegging demand date.

Engineering Changes (ECOs)

Oracle ASCP evaluates the engineering change orders as of their scheduled effective date. You can order material and plan resources that you need for new revisions ahead of time.

Note: The planning process only suggests implementing engineering change orders when the unconstrained start date of the planned order is later than the effective date. Oracle ASCP does not suggest a planned order using an ECO if the planned order needs to start before the effective date of the ECO.

For a pending ECO, you can specify whether to include the engineering changes during the planning process. Set the MRP Active Flag to Yes in the Engineering Change Order window if you want the planning process to consider the engineering changes on the ECO.

Oracle ASCP considers engineering changes when generating component requirements for planned orders and suggested repetitive schedules. The quantity specified by an engineering change order is considered if the scheduled effective date of the ECO is before the suggested start date of the order. For additional information, see Engineering Change Orders Use-Up Effectivity.

Substitute Components

Substitute components are modeled similarly to alternate resources. Each primary BOM component is assumed to have a set of possible substitutes. The primary item will be used instead of the substitute when it is available.

For more information, seeAssigning Substitute Components, Oracle Bills of Material User's Guide.

By-products

You can define negative usages for component items on a bill of material in Oracle Bills of Material. You can add by-products to discrete jobs using Oracle Work in Process.

Oracle ASCP includes by-products on standard and non-standard discrete jobs and components with a negative usage on a bill of material when netting supply and demand. Oracle ASCP considers this type of component requirement as supply available on the job completion date.

Note: You can manually add a negative requirement to a non-standard job in Oracle Work in Process to manage components that result in disassembly. You could use this option for repairing assembly units. It lets you track the item that is issued to the job as available supply on completion of the repair job.

Planned Orders

You can turn off planned order creation for an item.

Consider turning off planned order creation if your business has these or similar situations

To turn off planned order creation for an item, use Item Mass Maintenance and set item attribute New Planned Order Creation. Valid values are:

This item attribute applies only to these plan types:

Product Families

Product families improve plan performance, letting you plan further down the plan horizon. You can do the following at the product family level:

For more information, see Forecast Explosion..

Safety Stock

Order Modifiers

Order sizing is a set of item attributes that allow you to control the recommended order quantities for planned orders. The planning process creates planned orders using basic lot-for-lot sizing logic.

You can set order modifiers in the following forms:

Note: The planning process ignores order modifiers for items that have a phantom supply type.

Note: Order modifiers for supplied items may be defined by their suppliers.

For additional information, please refer to Items, General Planning Attribute Group and MPS/MRP Planning Attribute Group in the Oracle Inventory User's Guide.

Fixed Days Supply

The planning process places single orders for the quantity that covers the requirements for the user-defined number of days. When suggesting planned orders, the planning process looks forward this many days and accumulates all of the demand in that time period. It then suggests a planned order to satisfy the total quantity required for that time period.

If you use order modifier Fixed Days of Supply, the planning engine creates a single supply to cover multiple days of demand. During constraint-based scheduling, the planning engine may move the demand and supply dates such that you cannot reconcile the supply quantity to the demand dates and quantities. To attempt a reconciliation, Oracle recommends using the old due date on the planned order demands.

Fixed Order Quantity

The planning process places one or more orders for the user-defined quantity or repetitive rate.

Fixed Lot Multiple

The planning process places single orders in quantities that are multiples of the user-defined quantity or rate.

For example, when the fixed lot multiple quantity is 100 and the requirement equals 110 units, place a single order for 200 units.

Minimum and Maximum Order Quantity

The planning process places one or more orders for at least the minimum quantity, but no greater than the maximum quantity.

For discretely planned items, when the requirement for a given date exceeds the maximum order quantity, the planning process places multiple orders.

Rounding Order Quantities

You can define, for each inventory item, whether the planning process should round order quantities when the actual order quantity is calculated as a fraction. If you choose to round, order quantities are rounded to the next highest whole number.

Note: By rounding up, the planning process may suggest a planned order for more than what is actually needed. This extra quantity is carried over into the next period as supply.

This diagram shows the order in which the planning engine applies order modifiers to planned orders (precedence of order modifiers).

Requirement Integer Quantities

Use requirement integer quantities to instruct the planning engine only to pass dependent demand requirement quantities that are whole numbers. You set the instruction for each component of each assembly in each organization.

The order modifier item attribute Round Order Quantities instructs the planning engine that when it calculates a fractional quantity for an assembly supply order, it should round the assembly supply order quantity up to the next highest whole number. Fractional supply order quantities occur because of:

From the extra supply order quantities, the planning engine creates fractional dependent demands on the components to match those extra supply order quantities and carries pegging in fractional quantities through the lower bills of material levels. Pegging to fractional demand quantities is both inaccurate and difficult to understand when you actually make the components and subcomponents in whole number quantities.

To instruct the planning engine to round dependent demand quantities for components: