SY/T 6423.6-1999
石油天然气工业.承压钢管无损检测方法.无缝和焊接(埋弧焊除外)钢管分层缺欠的超声波检测
Petroleum and natural gas industries.Non-destructive testing (NDT)methods of steel tubers for pressure purposes.Ultrasonic testing of seamless and welded(expect submerged arc-welded) steel tubes for the detection of laminar imperfections
SYT6423.6-1999, SY6423.6-1999