摘要 |
A back-up ring assembly for a wellbore packer that acts as an extrusion limiter for a packing element and engages the wellbore bore, also operating as a slip to anchor the packer in place. A wellbore packer includes a single structure that acts both to back up the extrusion of the packing element and to engage the wellbore wall. For example, the structure is a back-up ring that includes a gripping structure on its outer wall-contacting surface. The wellbore packer includes: a mandrel, a deformable packing element surrounding the mandrel and adapted to be radially expanded out from the mandrel, the deformable packing element including an end; a back-up ring surrounding the mandrel and positioned adjacent the end of the deformable packing element, the back-up ring having an inner facing annular surface and an outer facing annular surface defining an outer diameter across the back-up ring, the back-up ring being expandable to increase the outer diameter to expand out from the mandrel alongside the deformable packing element and the outer facing annular surface including a gripping structure for biting into a constraining surface in a well. |