Framework Purchasing order used to procure materials or external services. Instead of stipulating a specific delivery date, this type of purchase order has an extended validity period.
Framework orders are defined via the document type FO. They are used in accelerated procurement processes in connection with maintenance/ servicing plans or invoicing plans, and for blanket purchase orders (purchase orders with limits).
A framework order covers multiple procurement transactions over a longer period in cases where the administrative costs of processing discrete POs would be disproportionately high.
It depend how you want to manage your PO process if the tolling process is recurring and for a long period of time then Framework PO could be considered.