System and apparatus for inspecting elongated welds

Claim 2

Ultrasonic apparatus for inspecting an elongated butt weld comprising, in combination: an inspection head adapted to be moved along and adjacent to the weld; a longitudinal wave ultrasonic transducer mounted on said inspection head and adapted to be positioned on said weld to move along its length for inspection through a substantial part of the heart of the weld; a plurality of shear wave ultrasonic transducers mounted on said inspection head to be positioned on each side of the weld to provide for inspection of the boundary zone of the weld, and means on the inspection head to restrain movement thereof to be longitudinally along the elongated weld without any substantial movement laterally of the weld.

Claim 3

The apparatus of claim 1 further including a pair of third ultrasonic transducers mounted on said inspection head for inspecting plate adjacent to and on each side of said weld.

Claim 4

The apparatus of claim 2 wherein said third transducers are longitudinal wave ultrasonic transducers.

Claim 5

The apparatus of claim 1 wherein said shear wave transducers are provided for inspecting each boundary zone of the weld and being mounted on said inspection head to be on one side of the weld, one of each pairs of transducers providing an ultrasonic impulse and the other of each pair of transducers receiving ultrasonic echo signals from said weld.

Claim 6

The apparatus of claim 4 including means for mounting each of said shear wave transducers so that the lateral distance of each transducers from weld being inspected may be adjusted, whereby the transmitting transducer of each pair may direct an ultrasonic pulse substantially into only one of the boundary zones of the weld, and the receiving transducer of each pair receives ultrasonic echoes from its respective only one boundary zone of the weld.

Claim 7

The apparatus of claim 4 wherein such a pair of shear wave transducers is mounted on opposite sides of said inspection head to be on opposite sides of said weld for inspecting the boundary zones on either side of the weld, and wherein the receiving transducers of a first pair of transducers on one side of said head is opposed to and in line with the transmitting transducer of a second pair of such transducers on the other side of said head, and the transmtting transducer of said first pair of transducers is opposed to and in line with the receiving transducers of said second pair of transducers.

Claim 8

The apparatus of claim 4 wherein said transmitting shear wave transducer includes a crystal mounted therein to provide an ultrasonic pulse at an angle with respect to the plate surface adjacent a weld to be inspected such that the pulse propagates through said plate on a path at about a 40*-50* angle with respect to surface of the plate, and said receiving shear wave transducer includes a crystal mounted therein for primarily detecting and responding to ultrasonic signals travelling through said plate on such a path.

Claim 9

The apparatus of claim 7 wherein said crystal is mounted so that said path is about 45*.

Claim 10

An ultrasonic inspection system for inspecting an elongated butt weld comprising, in combination: electronic drive means for providing periodic ultrasonic drive pulses, a first ultrasonic transducer connected to said drive means and responding to such drive pulses for inspecting a substantial portion of the thickness of such a bead; first time base measurement means connected to said first transducer for responding to echo ultrasonic pulses received by said transducer to provide a first distinctive output signal responsive to the condition of said weld; a plurality of second ultrasonic transducers connected to said drive means and responding to such drive pulses for inspecting thE boundary zones of such a weld; and electronic signal detecting means connected to said second ultrasonic transducer for providing a second distinctive output signal in response to an abnormal condition at at least one of said boundary zones, means mounting said transducers to be moved longitudinally along the weld without any substantial movement laterally of the weld, and a plurality of third ultrasonic transducers connected to said drive means and responding to such drive pulse for inspecting plate adjacent to and on each side of the weld, and second time base measurement means connected to each of said third transducers for responding to ultrasonic echo signals therefrom to provide a third distinctive output signal responsive to the condition of said plate.

Claim 11

An ultrasonic inspection system for inspecting an elongated butt weld comprising, in combination: electronic drive means for providing periodic ultrasonic drive pulses, a first ultrasonic transducer connected to said drive means and responding to such drive pulses for inspecting a substantial portion of the thickness of such a bead; first time base measurement means connected to said first transducer for responding to echo ultrasonic pulses received by said transducer to provide a first distinctive output signal responsive to the condition of said weld; a plurality of second ultrasonic transducers connected to said drive means and responding to such drive pulses for inspecting thE boundary zones of such a weld; and electronic signal detecting means connected to said second ultrasonic transducer for providing a second distinctive output signal in response to an abnormal condition at at least one of said boundary zones, means mounting said transducers to be moved longitudinally along the weld without any substantial movement laterally of the weld, and a plurality of third ultrasonic transducers connected to said drive means and responding to such drive pulse for inspecting plate adjacent to and on each side of the weld, and second time base measurement means connected to each of said third transducers for responding to ultrasonic echo signals therefrom to provide a third distinctive output signal responsive to the condition of said plate.

Claim 12

The apparatus of claim 9 further including a chart recorder having a first channel responsive to said first distinctive output signal to provide a first distinctive trace, a second channel responsive to said second distinctive output signal to provide a second distinctive trace, and a third channel responsive to said third distinctive output signal to provide a third distinctive trace whereby simultaneous inspection of said first, second and third traces can provide distinctive and composite indications of the condition of the heart of the weld, the condition of the boundary zones of the weld, and the condition of the plate adjacent the weld.

Claim 13

The system of claim 9 wherein the weld to be inspected is the long seam weld of racked pipe, and further including a carrier adapted to be inserted in and moved along the length of such pipe, and an inspection head resiliently mounted on aid carrier to move about and along said weld, and wherein said first, second, and third ultrasonic transducers are mounted on said inspection head.

Claim 14

Ultrasonic apparatus for inspecting longitudinal butt welds in a pipe comprising, in combination: a carrier adapted to be moved along the length of such a pipe; an inspection head resiliently mounted on said carrier and adapted to be moved along the weld to be inspected; means for guiding said head on the weld in a manner to cause the transducer to move longitudinally along the weld without any substantial movement laterally of the weld; means for urging said head against the inside wall of a pipe being inspected; a first ultrasonic transducer mounted on said inspection head and adapted to be positioned over said weld to move along its length for inspection through a substantial part of the weld bead; a plurality of second ultrasonic transducers mounted on said inspection head to be positioned and to provide for inspection of a root of the weld; and a pair of third ultrasonic transducers mounted on said inspection head for inspecting plate adjacent to and on each side of said weld.

Claim 15

Ultrasonic apparatus for inspecting longitudinal butt welds in a pipe comprising, in combination: a carrier adapted to be moved along the length of such a pipe; an inspection head resiliently mounted on said carrier and adapted to be moved along the weld to be inspected; means for guiding said head on the weld in a manner to cause the transducer to move longitudinally along the weld without any substantial movement laterally of the weld; means for urging said head against the inside wall of a pipe being inspected; a first ultrasonic transducer mounted on said inspection head and adapted to be positioned over said weld to move along its length for inspection through a substantial part of the weld bead; a plurality of second ultrasonic transducers mounted on said inspection head to be positioned and to provide for inspection of a root of the weld; and a pair of third ultrasonic transducers mounted on said inspection head for inspecting plate adjacent to and on each side of said weld.