Patent ID: 8342239
Filing Date: 2013-01-01
Classification: E21B

Abstract:
1. A swellable packer for positioning downhole in a well to seal with an interior surface of a borehole or an interior surface of a downhole tubular, comprising: a mandrel having a central axis and an exterior generally cylindrical surface; a swellable elastomeric sleeve-shaped body positioned over a portion of the exterior surface of the mandrel for swelling to seal between the mandrel and the interior surface of the borehole or the interior surface of the downhole tubular, the swellable elastomeric sleeve-shaped body is homogeneous and integral with a swellable elastomeric member; a rigid end ring positioned over the exterior surface of the mandrel and axially secured to the mandrel; an elastomeric anti-extrusion member spaced axially between the swellable sleeve-shaped body and the, rigid end ring, the elastomeric anti-extrusion member having a modulus of rigidity substantially greater than a modulus of rigidity of the swellable sleeve-shaped body, the elastomeric anti-extrusion member having a radial thickness adjacent the rigid end ring greater than a radial thickness of the elastomeric anti-extrusion member adjacent the swellable sleeve-shaped body; the swellable elastomeric member spaced radially between the exterior surface of the mandrel and the elastomeric anti-extrusion member adjacent the swellable sleeve-shaped body; and an outer diameter of each of the swellable sleeve-shaped body, the rigid end ring, and the elastomeric anti-extrusion member is substantially uniform prior to swelling of the elastomeric sleeve-shaped body.