Patent ID: 7497000
Filing Date: 2009-03-03
Classification: E21B,F16L,G02B,Y10T

Abstract:
1. A method for repairing a collapsed duct section, the collapsed duct section being accessible through a section of non-collapsed duct, the method comprising the steps of: moving a duct expanding head through the section of non-collapsed duct to a point adjacent the collapsed duct section; remotely applying power to the head through power lines extending the length of the non-collapsed section; the power displacing a duct wall expanding member of the head to engage a wall of the collapsed duct section and to force the collapsed duct section open, the duct wall expanding member engaging the wall of the collapsed duct section in a direction away from an engagement of another portion of the wall by a finger that is stationary with respect to the head; withdrawing the duct wall expanding member out of engagement with the wall; and removing the head from the duct.