Transfer batch

Transfer batching refers to operations that are planned with some overlap. The subsequent operation can already start when the previous one hasn’t completely finished yet.

Material is produced and/or consumed in smaller batches at various points during the operation.

Two examples of overlapping operations

Example

Excel spreadsheet transfer-batch

The model contains 2 examples. The rows in the above screenshot show for each example:

  • the loading of the assembly resource
  • the loading of the subassembly resource
  • the inventory between the assembly and subassembly operations
The first example models a case where subassemblies are produced in batches of 100 pieces. The assembly operation consumes these in batches of 100 pieces.
Notice how both operations run at the same time, and how material is transferred between both operations in a just-in-time manner.
The second example is more complex. The production rate of the subassembly and assembly operations is now different, the transfer batch size is also different, and there is a calendar defining the working hours.
Notice how the different duration of both operations creates some minimal and unavoidable work-in-progress inventory between both operations. Notice also how the material production and consumption is evenly distributed over the working hours of the operations - skipping any unavailable periods.

You can easily modify the example. You will obtain different inventory profiles in the buffer between both operations when you vary the operation duration and/or the transfer batch quantity.

Modeling transfer batches is straightforward:

  • Set the type of the operationmaterial record to “transfer_batch”.
  • Populate the field “transfer batch quantity” in the operationmaterial table. This defines the amount of material that is produced or consumed per batch.