Intelligent Pigging Technology To Inspect Process Heaters Coils

Reliable “intelligent pig technology” is now readily available to the refining industry which can provide quick / comprehensive inspection to both “convection” and “radiant” sections in process furnace piping coils. Both tabular data formats along with 2D / 3D high-resolution color graphics of the test results are immediately produced on site showing tube/pipe wall thinning, bulging, swelling, and ovality.

Serpentine furnace coils in petroleum and chemical plants present a significant challenge for the NDE inspector when applying conventional NDT methods. The coils significant length (occasionally +5,000 feet [1,524 m] per coil), extended surfaces, multiple short radius 180( return bends, and difficult access make furnace coils extremely difficult to inspect when applying conventional NDT methods. A remotely operated, autonomous inspection tool (intelligent pig), was developed which allows the inspection to be carried out in both the convection section and radiant sections without the need to access the furnace box.

During typical operation the intelligent pig is transported through the interior of the serpentine piping coil via a column of water which provides propulsion, and coupling for the ultrasonic transducers. The inspection data is processed and stored on board. The intelligent pig applies high-speed digital signal processing to enable production of instantaneous results upon retrieval of the intelligent pig from the furnace coil.