Non-contact method and apparatus for inspection of inertia welds

An apparatus for inspecting a workpiece having a laterally-extending portion of a first part adjoined by an inertia weld to one end of a second part having an outer surface extending away from the first part, comprising:

• a first electromagnetic acoustic transducer assembly, positioned in non-contact relation to the workpiece, for generating a pulsed acoustic wave inspection signal incident upon said inertia weld in said workpiece;
• a second electromagnetic acoustic transducer assembly, positioned in non-contact relation to the workpiece, for detecting acoustic waves in the workpiece and generating a detection signal, said first and second electromagnetic acoustic transducer assemblies being stacked in co-axial relation to the workpiece with said first electromagnetic acoustic transducer assembly being positioned between the second electromagnetic acoustic transducer assembly and the workpiece;
• and
• means for utilizing said detection signal to identify defects in said inertia weld.

An apparatus for inspecting a workpiece having a laterally-extending portion of a first part adjoined by an inertia weld to one end of a tubular second part having a cylindrical surface extending perpendicularly away from the first part and having a second end, said cylindrical outer surface having one or more designed discontinuities, comprising:

• a first electromagnetic acoustic transducer assembly, positioned in non-contact relation adjacent to said laterally-extending portion of said first part of said workpiece, for generating a pulsed acoustic wave inspection signal in said laterally-extending portion, said first electromagnetic acoustic transducer assembly including an electrically conductive coil oriented substantially perpendicular to said inertia weld, wherein said inspection signal includes shear acoustic waves polarized in a direction substantially parallel to said cylindrical outer surface of said second part;
• a second electromagnetic acoustic transducer assembly, positioned in non-contact relation adjacent to said laterally-extending portion of said first part of said workpiece, for detecting acoustic waves in said plate-like portion of said first part and for generating a detection signal, said first and second electromagnetic acoustic transducer assemblies being stacked in coaxial relation to the workpiece with said first electromagnetic acoustic transducer assembly being positioned between the second electromagnetic acoustic transducer assembly and the workpiece;
• and
• means for utilizing said detection signal to identify defects in said inertia weld and in said designed discontinuities.