How can I set up purchase-to-order much the same as make-to-order

Question

Hi all,
I apologise if this is posted in the wrong place but this is my first question that I couldn't answer by searching other posts/articles so I'm reaching out for some help and advice.
In PP, you can use a planning strategy to execute a make-to-order process which creates a production order specific to a sales order.  Is the same possible within MM for creating a purchase order specific to a material required for a production order?
My example is this:
The BOM for FINI_ABC contains:
     1 piece of PACK_1 (label)
     1 piece of PACK_2 (container)
If I create a production order for FINI_ABC, MRP will obviosuly create requirements and purchase requisitions for both PACK_1 and PACK_2 materials.  What I would like to achieve is for the production order number to be held within the purchase requisition and subsequently the purchase order.
This is required so that when the Purchase Order is created and sent to the vendor, they also receive the corresponding production order number.  The vendor is then able to deliver the PACK materials packaged together for production which obviously eliminates some manual handling in the production warehouse.
As you see, it's very similar to Make-to-Order but I don't know where to start..........
Any help or advice to point me in the right direction would be very gratefully received.
Many thanks,
Rob

Answer 1

Hi Rob,
Some care must be considered in respect to what materials will you be managing in your stock, if FINI_ABC or PACK_1 and PACK_2.
I'm guessing by your description you mean FINI_ABC.
I think you can create PACK_1 and PACK_2 as service materials and at your pricing condition for FINI_ABC you can define one of this "services" as a free goods item. Unfortunately you could only assign one item this way.
Another thing you can use is the empties management and set this two items in a empties BoM. Check:
http://help.sap.com/saphelp_erp60_sp/helpdata/en/43/0102827af25285e10000000a1553f7/content.htm
In SAP Retail you can be even be a bit more creative with BoM's in purchasing as I recall.
You can also follow a more simple rule albeit some development required. Create your PO with only your finished material and create a new BoM usage and your "Purchase BoM's" for this usage. Then you set your purchase order smartform or EDI message to read this information and place it on the layout. Although you don't get the info in ME23N your supplier will.
Hope it helps,
Edgar