As we all know that Part is customized product ,so the orders can't be cancelled after payment. But we have suggestions for you as below.
1. If the orders are not be paid,you can delete the order or contact your service people to change the CAD files.
2. If the orders are paid and don't start to produce,pls contact your service people .Maybe the orders can be cancelled.
3. If the orders are in production,we can't cancel the order. You can contact your service people to hold the shipment to save shipping cost.