Production planning: The sequence matters

By Gerald Scheffels for ifm

Starter, main course, dessert: With a good meal, the order is fixed. It's the same with football (kick-off, first half, break, second half) and with a symphony: first the overture, then three to five movements. In industrial production it is more difficult – even if most modern tools such as SAP are used. It can always happen that it "hooks" somewhere: on the machine itself, in the upstream process or in the downstream process. The reason: In the SAP standard – unless SAP APO is used – planning across several work centres is very time-consuming because no automation is possible. This, in turn, is due to the fact that such multi-work centre planning is extraordinarily complex. In order to realise it, one needs above all a suitable sequence. But how can this be determined?

Challenging, but not impossible: multi-work centre planning in production

For practical production sequence planning, in a nutshell, you need all relevant data and an intelligent evaluation of this data. Answered in more detail: A tool is needed that determines for each order,

• which material and/or which parts are needed,
• when the material/parts have to be at which work centre,
• which manufacturing processes are upstream and downstream,
• which rest and buffer times must be observed.

And – this is what makes the task so complex – these data not only have to be collected and correlated for each individual order. Also the order dependencies among each other determine whether production runs or comes to a standstill.

Pegging as relationship manager

Pegging is used to determine complex order structures even in the case of anonymous make-to-stock production. Only this enables optimisation of the entire production across all customer orders. The task is not trivial. It requires that unstructured individual orders become logical and coherent order chains. Complex algorithms check all order dependencies and calculate feasible production sequences. The software constantly determines other possible detailed production plans, compares the quality and offers the user an optimised plan at the end.