Patent ID: 11898412
Assignee: OIL LIFT TECHNOLOGY INC.
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 12:
13. A rod lock out clamp for use on a well bore in a production oil,
water or gas well installation, the lock out clamp comprising:
a housing having a central bore for receiving a rod in spaced relation therethrough;
clamp members in the housing for grippingly and frictionally engaging the rod in the bore, at least one of the clamp members having an inner end and a recess in the inner end, the recess having a profile with an arcuate portion having a radius of curvature that reduces from a maximum radius to a minimum radius; and
manipulating means coupled to the housing and the clamp members for moving the clamp members between a rod gripping position in which the clamp members grippingly engaged the rod to prevent rotation or axial movement thereof, and a retracted position in which the clamp members are removed from the rod to permit rotational and axial movement of the rod in the bore, wherein the recess includes an inner surface, the inner surface having a plurality of parallel notches.