planned order

hi all,

purchase order is released in plant A from PLant B for stock transfer of materialX for 10000tons. so a planned order is generated for 10000tons in plant A which is a supplying plant. for the same material X there is a requirement for plant A also for 50000tons. so one collective planned order is generated for 60000tons.

out of 10000tons of material A only 7000tons are supplied to plant B. 50000tons is produced for plant A. now the balance of 3000tons is remained in the palnned order which is of the open purchase order from plant B. ther are 4 planned orders from last four months which i want to delete as he requirement for child items are increasing becaus of 4 planned orders. can anyone tell me how to cancel those open purchase orders released items ORD DS. i tried to directly delete but was not possible. once there orders are cancelled then i can delete the planned orders by md12 or md16.

looking for some good and quick replies. thanks all.

sanju