Capital investment is not something that can be easily done today or tomorrow, but workers are a low-cost, flexible part of the workforce that can be reassigned or hired new, so increasing the availability of main resources through worker capacity planning is a very significant part of plant management.
The number of molds held, set-up time for mold replacement, mapping of molds to resources, maintenance schedules, etc. have a significant impact on production planning based on the main resources, and sub-resources that are constraints on the main resources, such as workers and molds, can be reflected in production planning.
Constraints of the mold and how to set up internal and external setups
If you set sub-resources and set the pre-setup task to 0 or blank for both main and sub-resources, you can express that pre-setup time does not occur, but there are only constraints on the number of molds held.
For example, if the pre-setup time for the main resource CUT is set to 120 minutes and the pre-setup time for the sub-resource CUT is set to 0, then the machine is stopped for 120 minutes of internal setup time.
In contrast, if the die change time is set to the pre-setup time for sub-resources, it becomes an external setup (setup that is performed without stopping the line or machine), for example, if the pre-setup task for main resources is blank and the pre-setup task for sub-resources is set to 120 minutes, the machine continues to operate during the 120-minute external setup time.
Adjustment of planned work time according to worker constraints and resource volume
Like a mold, workers can be considered as a sub-resource, and can be reflected as a constraint on the planning of the main resource. In this case, a conditional expression is set for the sub-resource effective condition of the sub-resource, which is the worker, that the worker can operate.
Workers are assigned as sub-resources to the main resources used in the process (pre-setup task or manufacturing task), and the number of workers is adjusted using the amount of resources in the calendar, and the resource constraints in the resource table are changed according to the amount of resources to be used, which is reflected in the planned work time.
- Set up sub-resources (workers) for the relevant process in the manufacturing BOM
- Set the resource constraint for workers in the resource table to infinite capacity.
- Increase the amount of resources in the calendar table while checking the load status.
Equipment is available, but constraints are placed on the allocation sequence.
Even if there is plenty of room for equipment, the influence of a limited number of sub-resources such as molds and workers will have an effect on the production plan, in other words, by setting sub-resources it is possible to put a restriction on the order in which the equipment production plan is allocated.
If there is room in the facility, the production scheduler will allocate work to vacant facilities and create a plan that can be completed in the shortest amount of time, but if there is a constraint that a later project cannot be started until the previous project is completed, then by setting up sub-resources that are common to the production processes of both projects, it is possible to create a production plan that can be completed in the shortest amount of time. You can create a serial production plan.