Device for detecting flooding of a hollow structure.

摘要

An inspection device detects flooding in a hollow structural member such as the leg of an oil or gas rig so as to detect the presence of through wall cracks in the member. The device comprises an ultrasonic transducer 19 for transmitting a pulsed beam of ultrasonic sound to pass through opposing faced walls or wall portions of the member and a visual indicator 32 responsive to time spaced echoes of the ultrasonic beam reflected respectively from the opposing walls or wall portions and received by the transducer 19 to indicate the presence or absence of flooding in the member. The transducer 19 is located in the bridge plate 10 of a jig and its beam passes through an aperture in a support frame 8 of the jig. The support frame 8 has a pair of spaced magnetic feet 16 attached to a bracket 15 on the frame 8 and a further magnetic foot 17 secured to the frame 8, the feet permitting the jig to be clamped onto a steel rig member so that the transducer can be optimally aligned with the member to optimise received echoes.

The bridge plate 10 is movable in two orthogonal planes by adjusting control knobs 12 and 13 so as to optimise alignment. A further visual indicator 31 also responsive to the echoes from the transducer 19 is adjustable to indicate whether the transducer 19 is optimally aligned and only when the transducer 19 is optimally aligned is the presence of flooding, if indicated by indicator 32, taken to be valid.