Hi Hariyappa,
sorry for my previous post, the function module i have sujjested earlier was for
reservation purpose.
Now for production please see these function modules.
CO_XT_COMPONENT_CHANGE, it can be used to change about material quantity,
CO_XT_ORDER_PREPARE_COMMIT , to commit
CO_XT_COMPONENT_ADD , to add new components
if you didn't get how to do it, please see this link, here it is better briefed.
Please change is according to your use.