Patent ID: 9376881
Filing Date: 2016-06-28
CPC Classification: E21B

Claim Text:
1. A wellhead assembly, comprising: a wellhead having a bore having a plurality of wickers, the wickers being parallel grooves joining each other at crests; one or more casing hangers landed in the bore below the wickers; an annular lockdown bushing coaxially inserted into the bore; a locking ring set in an annulus between the lockdown bushing and the wickers and selectively moveable from a running position spaced radially inward from the wickers to a set position in non sealing contact with the wickers, the locking ring having an outer diameter surface that is free of grooves in the running position and that has deformations formed by embedding of the crests of the wickers into the outer diameter surface when in the set position; and an energizing ring having an annular portion in contact with an inner diameter surface of the locking ring for moving the locking ring from the running position to the set position in response to downward movement of the energizing ring.