How to consumme components at subcontractor's end?

Hi Experts,

I have two cases where I send Equipment or any Material for repairing.

1. Motor is required to be sent for repairing. We will give the Bearings for replacement.

2. Transformer is requird to be sent for overhauling. After overhauling it will be filled with new transformer oil. This oil be given by us to the subcontractor.

In both the above cases how to proceed so as to make the consumables to be consummed at subcontractors' end?

kindly advise.

Thanks in advance,

Sachin S. Kundap