Remote Inspection Tool Developed to Provide Inspection for Complex Furnace Tube Configurations - Part 2 of 2

Part 1 included a review of current tube inspection practices in convection and radiant sections of heaters/furnaces in the refining and chemical industries. The authors also presented a new inspection device combining laser image mapping of the internal surface of tubes and ultrasonic thickness mapping. The new tool is propelled through the tubes by water and has demonstrated the ability to inspect and pass through 1D, 180 degree return bends in addition to providing a full inspection of the straight runs, up to 2000’ in one inspection. Part 2 now covers data analysis and an interview to bring ‘IJ’ readers fully up to date on the emerging technology.

Data Analysis

Once the data is downloaded to the data station, software is used to process and view the data. The software is a robust Windows NTTM application that takes full advantage of the Windows graphical user interface. The software automatically identifies straight sections of tubing and categorizes the flaws within each section based on user definable limits. A table of sections provides the user instant tabular information on the most severe flaws within a section. From the table of sections, the user may choose to view the data in either a cross-sectional format or a C-scan view. Multiple views may be displayed simultaneously, with linked navigation among the views. The cross-sectional view is often useful for determining ovality of the tube at a given axial position while the contour view is very useful for viewing generalized wall thinning and corrosion.

As data is reviewed, an automatically generated tubing inspection report can be edited with the addition of comments and data snapshots to produce a detailed hard copy report of the tube’s condition.

The device requires a single entry point into the furnace tube, a single exit point from the loop and an available supply of clean water.