Patent ID: 8739889
Filing Date: 2014-06-03
Classification: E21B

Abstract:
1. A downhole tool comprising: a tubular member comprising an outer wall surface; a housing disposed on the tubular member, the housing comprising a housing chamber; an expandable member disposed in the housing chamber, the expandable member comprising an interior portion, an outer wall surface, a contracted position, and an expanded position the outer wall surface of the expandable member partially defining a sealed chamber within the housing chamber; and at least one port disposed through the housing, the at least one port being in fluid communication with the interior portion of the expandable member and an outside environment, wherein the expandable member moves from the contracted position toward the expanded position due to a pressure increase within an annulus of a wellbore outside of the tubular member, and the expandable member moves from the expanded position toward the contracted position due to a pressure decrease within the annulus of the wellbore outside of the tubular member.