Queary on excise duty

Dear Sir, My company has a manufacturing unit in haldia. the company is manufacturing steel drums for IOCL. the raw materials of the products supplied by IOCL. we are just fabricated the raw materials and made drum for IOCL. my question is should we charge excise and service tax both on bill? can anybody charge the both tax on bill? this is very urgent. please reply. regards Asim jana