How the CIR are consumed by the sales order ?

Dear All;

I'm currently testing the  strategy 40 (MTS) and I am at the level of planned independent requirements (MD61) and customer requirements (MD81). I created PIR (Type VSF),  CIR (Type KSV) and a sales order.  Well, I noticed that the PIR are consumed by the CIR and SO.  However, I do not see when the CIR are consumed by the customer order.

Is it possible to explain this point, because despite my research I can't find a clear answer. 

Thanks in advance to you all.