Automated boiler wall cleaning and inspection

Abstract

Power plant boilers need to be cleaned and inspected on a regular basis. Boiler chambers can be up to 50m high requiring scaffolding for all works on the water walls. The scaffolding itself can take several weeks. To overcome the disadvantage of the time consuming scaffolding work an automated boiler wall crawler for wall cleaning and inspection is being developed by Alstom in collaboration with Alstom Inspection Robotics and Waterjet Technologies. The automated system will be able to drive up the water wall with the cleaning or inspection application integrated and no scaffolding will be required anymore. The cleaning application consists of a patented suspension cleaning technology where abrasive and water are mixed and pumped up to a defined pressure. The inspection will be done using latest ultrasonic technology to measure remaining wall thicknesses of the tubes. The deployment system consists of two magnetic track drives connected by a frame and two passive magnetic wheels. Laboratory tests have shown promising results. The system is able to drive up and down the water wall during the cleaning with the system running at around 100 bar.