Patent ID: 8550178
Filing Date: 2013-10-08
Classification: E21B

Abstract:
1. An expandable packer for subterranean use to engage a borehole wall, comprising: a mandrel having a passage therethrough, said passage having a first internal dimension that is constant for a predetermined length defining at least one first zone and a second internal dimension larger than said first internal dimension to define at least one second zone; said second zone comprising a multidimensional shape with opposed surfaces that either are joined together or that are separated by an intermediate surface to define an empty volume such that expansion of said first zone causes incremental radial expansion of said second zone that increases the internal dimension of said second zone incrementally beyond the expanded internal diameter of said first zone due to opposed sloping surfaces in said second zone moving toward each other as said mandrel shrinks axially from first zone expansion; and at least one seal mounted externally to said mandrel in said first zone and selectively pushed from within by said mandrel to engage the borehole wall without mandrel penetration into said seal.