Figure 5: Three layers of planning and execution
The lower level is the short term planning, determining the run-lengths of the non-cyclic blends
and the allocation of the blend runs to the sku’s. Special attention is given here to an adequate
alternation of 1.25l and 2l boxes during the production of blends with a relatively high yield. The
short term planning is executed weekly. It is run-out time based. Just before the start of the cycle,
the necessary information (inventory, work-in-process, orders, predicted requirement) is
downloaded from SAP. An Excel application (LP-solver) is used to determine the allocation of
the cyclic batches to the sku’s and also to determine suitable runs for the non-cyclic blends. This
is done by the SCCG group. The information is transferred to the DPSG group, to take care of
the timely availability of green beans plus the roasting schedule and to determine the packaging
sequence and the schedule of the variable period. The resulting production schedule is uploaded
to SAP, to keep the SAP transaction processing complete.
At the execution level, the people have to determine the precise evaporation and centrifugation
sequence and timing. They also have to know how to deal with extraction disturbances and to
determine the extent to which the breathing blend has to buffer these disturbances. There is also
some freedom left in the packaging sequence. During the pilot the simulation model is used to
explore the possibility to guide this decision freedom with simple rules.