20110203676 | PIPE PIG AND METHOD OF CLEANING A PIPE - A pipe pig for refinery heater tubes is disclosed. The pipe pig has arcuate cleaning elements which form an expandable circumference. Each of the arcuate cleaning elements has a scraping edge. A spring element biases the arcuate cleaning elements radially outward. The pipe pig may have structural components made from titanium alloys and arcuate cleaning elements made from carbon-carbon composites. A method for cleaning coking out of refinery heater tubes using the pipe pig is also disclosed. | 08-25-2011 |