Accelerating tube up grading on HI-13 tandem was finished in 2002. It was carried out after 15 years’operation of the HI-13 tandem accelerator.Eight old 72“tubes were replaced by one 96” tube and seven88“ tubes therefore the terminal voltage of the machine could be promoted from 13 MV to 15 MV ormore. The main task of this project is: (1) import 8 extended accelerating tubes and a multi-target putter Accelerating tube up grading on HI-13 tandem was finished in 2002. It was carried out after 15 years’ operating on the HI-13 tandem accelerator. Light old 72 ”tubes were replaced by one 96" tube and seven88 tubes therefore the terminal voltage of the machine could be promoted from 13 MV to 15 MV ormore. The main task of this project is: (1) import 8 extended accelerating tubes and a multi-target putter