What is and when we will be using backflushing consumption? Method for issuing (reducing on-hand quantities) materials to a manufacturing order. With backflushing, the material is issued automatically when production is posted against an operation. The backflushing program will use the quantity completed to calculate through the bill of material the quantities of the components used, and reduce on-hand balances by this amount.
Things to consider …
What NAV design is on this topic? Manufacturing Training material provides the following explanation: When you use the backward method, this is based on actual quantities. Having this in mind, if you scrap, you might want to take care of this since backflushing is based on actual quantities and once you manually post scrap, NAV expects you to manually post actual consumption as well.
One thing to keep in mind when using back flushing (or forward flushing) is that NAV does not take any manual consumption into account. I.e., it will consume material regardless of the "remaining quantity" required.
For example, a prod order requires 2 of component "A", and "A" is set to back flush (on purpose or by accident). If you manually consume 2 of "A", NAV will still back flush another 2 on output or finish (depending on setup).
This can cause unintentional over-consumption of components, and can be very painful to fix if the flushing occurs when finishing the prod order.
One could argue that this is or isn't appropriate behaviour, but my preference is that back flushing (or forward flushing) does not over-consume material. There are fairly easy mods that can be done to prevent over-consumption, or you can just have logic that sets the flushing method on the component(s) to manual if manual consumption is posted.