Several years ago, I ran into a customer producing items with different variants. In particular, each item was made in different colors, and consequently the production BOM was different for each paint. The MRP engine should propose to buy the correct paint, in the correct quantity and at the correct date.
Sometimes during my courses I enjoy myself in telling this story, because I had to develop a customization requiring 7 hours of brainstorming translated into just two lines of code! This anecdote is useful because it remembers that one of the engineer asking 4000 Euros to tighten a screw, and remembering its angry customer that for knowing that the problem was that specific screw, were necessary 30 years of experience and not just few minutes of work. So finally the customer saved its money.
But let’s go back to the point. As everyone using the manufacturing module knows, production BOM and routings are associated to the item on the Item Card
Since October 2021 we have the possibility to associate this info on the Stockkeeping Unit (SKU). To this day SKUs have been mostly used for different locations, when each item has different planning criteria in each location.
We probably don’t think about the possibility we have to create SKUs not only for each location, but for each variant as well. Now comes the best of it.
Let’s suppose we need to produce our famous Bicycle number 1000 in two different colors: blue and red. To manage this, as a first thing we’ll create two variants for the item
We’ll have then two different production BOMs: one having the blue paint
and the other with the red paint
Now we just need to create two SKUs for the bicycle, one for each variant and for the paints as well.
To make it easier, I used just Location BLUE for all the items. On each SKU for the bicycle we must set the production BOM.
After creating a gross requirement of 10 blue bicycles and 10 red bicycles, if we run the MPS/MRP engine, we can see this result:
As we can see, for each variant the engine used the correct BOM and consequently the MRP proposes to buy the paints too.
Now the only thing to understand is how long did developers take to make this modification: I guess less than me.
Routings on SKUs
Now the question can be in which cases should we have different routings in different SKUs. Even if I personally never found a similar situation, the first thing to think about is mapping the correct machines into the routing: if we produce in a factory (location) we use certain machines, if we produce in another factory we use different ones. Routing is the same, but not the machines involved.
In this way CRP (Capacity Requirements Planning) can be more precise.