Phased array ultrasonic NDT system for tubes and pipes

A system for the non-destructive testing of a tube having a tube wall to detect the presence of defects within said wall, including one or more modules each comprising:

• (a) one or more ultrasonic phased array probes, each including a first plurality of ultrasonic elements;
• (b) means to supply electrical signals to the ultrasonic elements to cause them to emit ultrasonic, phased array beams that respectively form a focal point;
• (c) an acoustic coupling fluid contained within a column extending from said one or more probes to the foot of said column;
• (d) acoustic coupling means extending between the foot of said column and a portion of the tube wall that serves as an ultrasonic entry zone for accessing the tube wall, and
• (e) means to receive defect-reflected sound returning from an entry zone on a tube wall to detect defects within the tube wall,
• wherein said first plurality of ultrasonic elements are arcuately deployed side-by-side to each other in a 1-dimensional arcuate array, in the shape of a portion of the circumferential surface of an imaginary cone, and wherein said elements provide ultrasonic beams that are directed to strike the outer surface of said tube at said entry zone from a plurality of approaching bearing angles, at an angle of incidence that will permit said beams to penetrate within the tube wall of a tube positioned beneath the acoustic coupling means.

A method of nondestructive testing for defects in the wall of a tube as an inspected member to be inspected comprising:

• (a) presenting the wall of such tube to a phased array (PA) ultrasonic probe system at an inspection station;
• (b) causing the inspected member to be rotated continuously while it is moving past said inspection station;
• (c) including at the inspection station at least one ultrasonic phased array probe having ultra-sonic ultrasonic elements that provide a plurality of focused ultrasonic beams which are directed at an entry zone on the outer surface of the tube wall that accesses an inspection volume within said tube wall, said beams arriving at the entry zone at a constant inspection angle along a plurality of conically oriented paths;
• (d) causing said beams to enter the inspection volume within the wall of the tube whereby sonic reflections are created by defects within the inspection volume;
• and
• (e) detecting said reflections with an arcuately deployed array of ultrasonic sensors positioned to receive such reflections.