About Pull Planning

Pull planning is the process APS uses to backward plan a demand from its need date. Starting with the last operation in the end item's routing, the system searches for available supplies (such as purchase orders), inventory, and/or resources to complete the demand on time. The pull-planning process follows this sequence:

• Search backward from the demand's due date to allocate planned supplies of the end item. If sufficient planned supplies are available to satisfy the demand quantity, the planning is complete.
• For any unsatisfied demand quantity, search backward from the due date to allocate on-hand inventory. If sufficient inventory is on hand to satisfy the demand, the planning is complete.
• If the previous two backward searches do not satisfy the demand quantity, search forward from the demand's due date plus the time defined by the Supply Usage Tolerance value. In this situation, where the system must allocate planned supplies within tolerance, it allocates as much of these tolerance supplies as possible before allocating earlier, non-tolerance supplies or on-hand inventory.
• For any unsatisfied demand quantity, create a planned order.
• If, at any level of the BOM, the system cannot plan the operation with enough time remaining to plan all remaining previous operations, the pull-planning fails and the system instead push plans the entire demand.
• If the item has a value specified in the Order Minimum field on the Items form, and the planned order quantity (the quantity the system plans to make or purchase) will satisfy the entire demand quantity, the system frees the supply and inventory already allocated.

If the item being planned has a Time Fence defined, the pull-planning process includes additional steps.