Procurement and activity planningfor a production line provider

Consider a production line provider with the following problem. Turnkey production lines should be delivered to global clients by contractual due-dates. Machines in the production lines can be bought from suppliers or built in-house. Since the production lines for different clients are of the same type -albeit of different capacity- they consist of similar or same machines. Thus, their purchase and/or production need to be coordinated to reduce costs and production time. Furthermore, capital and workforce resources are constrained. Hence, not all activities can be done in parallel and should be spread across the planning horizon. Delivery delays have monetary fines proportional to the time past the due-dates. The company is concerned about making the due-dates by observing all resource constraints and carefully coordinating the activities of the concurrent projects. We give mixed-integer linear programming formulations for the investigated problems and report the results of the numerical experiments conducted using these formulations.