Home / Standards / GBT 23908-2009 GBT 23908-2009 Non-destructive testing — Contact ultrasonic pulse-echo direct testing method 无损检测 接触式超声脉冲回波直射检测方法 Standard Type GBT ICS N/A CCS N/A Status N/A Issue Date N/A Implementation N/A Responsible Dept N/A Drafting Unit N/A