Patent attributes
A radially expandable backup ring (50) with relatively rigid segments (56) and relatively resilient segments (58) that are integral with one another to circumferentially urge the relatively rigid segments (56) together when the backup ring (50) expands. The backup ring (50) may radially expand to reduce or eliminate a radial gap between the backup ring (50) and a radially inwardly facing surface of a corresponding cased wellbore (22) to prevent or minimize axial extrusion of a corresponding sealing member (32), such as a compressible packer seal of a cased-hole retrievable packer assembly. The relatively resilient segments (58) allow the backup ring (50) to elastically expand and retract to prevent axial extrusion of the sealing member (32). The relatively rigid support segments (54) may be axially aligned with a corresponding relatively resilient segment (58) of the backup ring to prevent axial extrusion of the sealing member (32) through the corresponding relatively resilient segment (58).