Integral Logistics Management — Operations Management and Supply Chain Management Within and Across Companies

14.4.2 Rough-Cut Infinite Loading

Intended learning outcomes: Present an example of a resource profile for one rough-cut work center. Describe the result of rough-cut capacity planning with deferred completion date. Explain rough-cut capacity planning with two rough-cut work centers and the result after moving the completion date of one operation.


Rough-cut infinite loading corresponds to infinite loading, in this case based on the resource profile for rough-cut work centers presented in Section 14.4.1.

Here, we multiply the product load profiles related to a particular batch size (generally = 1) by the batch size and add a desired completion date. The orders thus defined are then considered in a particular planning order. The priority can be determined by

  • The latest completion date
  • The latest start date
  • The external priority (importance) of the order

When all orders have been loaded in this way (with no intervention from the planner) onto an existing “preloading,” we obtain a resource profile that is typical of infinite loading. Figure 14.4.2.1 shows, as an example, the resource profile presented in Section 14.4.1. with loading from the earliest start date.

Fig. 14.4.2.1       Example of a resource profile for one rough-cut work center.

The planner then either defers the capacities or brings them into line with one another:

  • If rough-cut planning is performed in the master planning, that is, in the long term, capacities are flexible with respect to quantity. Indeed, determining such quantities is one of the objectives of long-term planning.
  • If rough-cut planning is applied to the medium or short term, it provides decision support to accept, reject, or defer a waiting order. Capacity is then somewhat less flexible, which means that it will not always be possible to meet the desired comple­tion date. In this case, the loading proceeds individually, order by order, with possib­le intervention by the planner after every order. If there are just one or two rough-cut work centers, this does not entail a lot of work, even if there are a lot of orders.

Figure 14.4.2.2 shows a possible response the planner can take to the overload shown in Figure 14.4.2.1. The planner can push the completion date back to the closest date that would produce an acceptable overload. Efficient algorithms highlight the order to be deferred by means of special graphical attributes (such as different colors) and automatically adjust the resource profile after rescheduling (generally using the mouse).

Fig. 14.4.2.2       Result of rough-cut capacity planning with deferred completion date.

Figure 14.4.2.3 shows the same resource profile, this time with two rough-cut work centers. The desired completion date causes an overload at rough-cut work center 2. In Figure 14.4.2.4, it has been brought into line by deferring the completion date by two periods.

Fig. 14.4.2.3       Rough-cut capacity planning with two rough-cut work centers.

Fig. 14.4.2.4       Rough-cut planning: result after moving the completion date and operation 5.

Detailed planning may nevertheless still be needed if we use short-term rough-cut planning. The individual rough-cut operations for the order under consideration can then be shown separately. It is only by recording interdependencies between operations in the network plan that we are able to move the fifth operation forward from the period [19–20] (overload) to the period [18–19] (no overload), as shown in Figure 14.4.2.4. To be able to work efficiently and interactively, it must be possible to view all the work centers at the same time. The entire resource profile for an order can then be moved at all the work centers simultaneously.



Course section 14.4: Subsections and their intended learning outcomes

  • 14.4 Rough-Cut Capacity Planning

    Intended learning outcomes: Describe rough-cut network plans and load profiles. Explain rough-cut infinite loading and rough-cut finite loading.

  • 14.4.1 Rough-Cut Network Plans and Load Profiles

    Intended learning outcomes: Present an example of a rough-cut network plan with two rough-cut work centers. Explain the resource profile of both rough-cut work centers as well as the resource profile for the combination of the two rough-cut work centers.

  • 14.4.2 Rough-Cut Infinite Loading

    Intended learning outcomes: Present an example of a resource profile for one rough-cut work center. Describe the result of rough-cut capacity planning with deferred completion date. Explain rough-cut capacity planning with two rough-cut work centers and the result after moving the completion date of one operation.

  • 14.4.3 Rough-Cut Finite Loading

    Intended learning outcomes: Present the cumulative resource profile of an order as well as cumulative load and capacity before loading the order. Explain rough-cut planning of the cumulative load and capacity after loading the order.

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