Operation Routings

It is possible in frePPLe to declare an operation of type routing. This operation type represents a set of suboperations that must be run in sequence. It is not possible to define a buffer between two suboperations of a routing operation.

An example of a routing

In the above example, four operations have to be defined in the operation table :

  • An operation named “Build Product” of type “routing” : by declaring this operation as a routing operation, you are modeling a virtual operation that is actually composed of other (real) operations in sequence. The item field of the operation table has to be filled with the produced item of the routing: Product in our example.

  • An operation of type time_per named “GRIND” to grind the raw product. The item field of the operation table must be empty. Note that this operation consumes the capacity of a resource named “Grinder”.

  • An operation of type time_per named “PAINT”. The item field of the operation table must be empty. This operation follows the grinding operation and requires paint pots.

  • An operation named “DRY” that is an operation of type fixed_time as whether one or a hundred parts have to dry, it is going to take the same time. The item field of the operation table must be empty.

Operation table:

Operation

Item

Type

Build Product

Product

routing

GRIND

time_per

PAINT

time_per

DRY

fixed_time

Now that the four operations have been declared, we need to fill the table suboperation to declare that operations GRIND, PAINT and DRY are suboperations of “Build Product” operation and also declare in which sequence these operations are performed. To define the suboperations sequence, the priority field should be used :

Suboperation table:

Operation

suboperation

priority

Build Product

GRIND

1

Build Product

PAINT

2

Build Product

DRY

3

Last but not least, table operationmaterial has to be filled. Any suboperation can consume items (though this is not of course mandatory) but only the last suboperation in the sequence can produce an item :

Operationmaterial table:

Operation

item

quantity

GRIND

Raw Product

-1

PAINT

Paint pot

-1

DRY

Product

1

The model described above can be found in the following Excel file:

Excel spreadsheet operation-routing