The firming type dictates the behavior of planning with PTR (Planning Time Fence), i.e whether the system should automatically firm the unfirmed planned orders and purchase requisitions, which are outside the PTF as they move to fall within PTF as days progress and also if new planning proposals are needed to be created to cover the shortage within PTF.

There are five firming types, viz. 0, 1, 2, 3, and 4.

Listed below are the characteristics of these four firming types:

0 - PTF has not effect on planning.

1 - All unfirmed planning proposals (planned orders/purch reqs) moving into PTF will automatically be firmed by the system, thus protecting them from anymore automatica changes due to subsequent planning runs). At the same time, if the MRP engine identifies any shortage within PTF, the system will create  new planned orders, but schedule them to lie JUST outside the end of PTF, thus leaving them as unfirmed elements.

2 - All unfirmed planning proposals (planned orders/purch reqs) moving into PTF will automatically be firmed by the system, thus protecting them from anymore automatica changes due to subsequent planning runs).  BUT, the system will NOT create any new planning proposals to cover the shortages identified within PTF. The shortage is left as a -ve qty for the planner to deal with manually.

3 - No automatic firming of any unfirmed planned orders, even if they move into PTF. They will be moved out to lie JUST outside the PTF. The system will create new proposals to cover the shortage but schedule them outside the PTF and keep them as unfirmed.

4 - No automatic firming / No automatic creation of planning proposals to cover shortage.
 
SAP PP Tips by: Muthu Chinnadurai

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