Operation Type

Different operation types are available:

  • Fixed_time

    The duration of the operation is constant, regardless of the quantity being planned.

    A typical example is a transport operation: transporting 1 piece with a truck takes just as long as transporting 100 pieces.

  • Time_per

    The duration of the operation increases linearly with the planned quantity. The total duration takes the form of ‘A + B * quantity’, where A and B are constants.

    A typical example is a production operation: there is a fixed overhead of machine setup at the start, and the actual production is linear with the quantity to produce.

  • Split

    This operation type plans the demand proportionally over a number of operations, based on pre-defined percentages.

  • Routing

    This operation type represent the sequence of operations that need to be run in sequence.

  • Alternate

    This operation type represent the choice between alternate operations to achieve the same result. Another cookbook recipe is dedicated to this.
    In the majority of models you don’t have to explicitly use alternate operations in your model. FrePPLe will automatically create them as soon as there are multiple replenishment methods.

The actual duration for the operation respects the working hours and holidays periods. These are defined in the available calendar of the operation and/or its location. The time between the start and end date of a manufacturing order or distribution order will then be extended with any unavailable time.

Example

Excel spreadsheet operation-type

This example has a transport operation of type fixed_time and a production operation of type time_per.