Tube challenge

Heat exchangers are widely used in numerous industries - they can be found in power stations, chemical plants, petrochemical plants, petroleum refineries, natural gas processing, and sewage-treatment works.

Regularly inspecting the tubes inside such heat exchangers is vitally important to ensure that the units are performing optimally. Any flaws in such tubes - such as pitting of the tube walls, erosion, holes, blockages and bulges - can cause the heat exchangers to fail or work less efficiently. At the very least this can result in higher energy costs for plant operators, although it can also cause catastrophic failures that damage expensive equipment (such as turbine bearings) and require expensive and unexpected stoppages for repairs.

There are a number of systems that are used to perform such inspection functions, including eddy-current and ultrasonic probes, as well as video scanners. Unfortunately, all of these systems have their own set of drawbacks. While some, for example, are unable to access the complex tube configurations found inside some heat exchangers, others can only inspect tubes made from certain materials. More problematic is that they all rely on the expertise of trained technicians who must first traverse a probe through the tubes in the exchanger and then manually interpret the results from the data collected.