METHOD OF NONDESTRUCTIVE QUALITY CONTROL OVER CIRCUMFERENTIAL WELDS OF TRUNK PIPE-LINES LAID UNDERWATER Russian patent published in 2003 - IPC

FIELD: construction and repair of underwater oil and gas pipe-lines. SUBSTANCE: in correspondence with proposed method of nondestructive quality control over circumferential welds of trunks pipe-lines laid underwater weld is exposed to radiation with the use of flaw detector. Prior to this film placed in insulation material is put on surface of weld of underwater pipe-line and is fixed on tested weld of underwater pipe-line. Flaw detector is isolated from external medium by its placement into chamber before lowering into pond to point of weld test. EFFECT: potential for quality control over circumferential welds of underwater pipe-lines. 2 dwg