The Economiser Penetration Scanning Mechanism or EPSOM was developed for ultrasonic inspection of a number of circumferential welds on economiser penetrations on the Advanced Gas cooled Reactor (AGR) power station – a design used in the UK. This weld was located approximately 5.2m from the edge of a shutter tube.
The manipulator fits between the inner and outer pipes of the economiser which limits the radial thickness of the manipulator to 40mm. The inspection is carried out by scanning up to eight probes over the external surface of the inner pipe.