Abstract An anchoring device that is useful in well bores to retain tubing strings, packers or the like in a fixed position therein. The anchoring device includes several hydraulically actuated piston slips and is provided with a retaining member that includes one or more deformable tabs that engage the slips to prevent the slips from moving outwardly until the hydraulic force exceeds the deformation strength of the tabs. The arrangement is such that inadvertent expansion of the slips and, thus, dragging of the slips on the wall of the well bore in response to a differential pressure created by the movement of the tool through the well bore is prevented. The slips are positively restrained until a pressure sufficient to deform the tabs is deliberately applied whereupon the slips are moved into holding engagement.
In apparatus to be lowered into a well bore: a body having a fluid passageway and a lateral opening in said body communicating with said passageway; a gripping member moveable in said lateral opening in response to pressure in said body into gripping engagement with the well bore wall; and a retainer member constructed from a substantially nonresilient material and mounted on said body and having a deformable tab portion engaging said gripping member, said retainer member preventing movement of said gripping member toward the well bore wall until the pressure exerts a force on said member sufficient to deform said tab portion.
Claim 2
Dependent Claim
103 words
In apparatus to be lowered into a well bore: a body having a fluid passageway and a lateral opening in said body communicating with said passageway; a gripping member moveable in said lateral opening in response to pressure in said body into gripping engagement with the well bore wall; and a retainer member constructed from a substantially nonresilient material and mounted on said body and having a deformable tab portion engaging said gripping member, said retainer member preventing movement of said gripping member toward the well bore wall until the pressure exerts a force on said member sufficient to deform said tab portion.
Claim 3
Dependent Claim
15 words
The apparatus of claim 1 wherein said retainer member extends completely across said lateral opening.
Claim 4
Dependent Claim
22 words
The apparatus of claim 2 wherein said gripping member has a slot therein adjacent to and sized to receive said retainer member.
Claim 5
Dependent Claim
27 words
The apparatus of claim 3 and also including resilient means engaging said retainer member and said gripping member for biasing said gripping member relatively toward said passageway.
Claim 6
Dependent Claim
43 words
The apparatus of claim 4 wherein said retainer member has a deformable second tab portion, said second tab portion engaging said gripping member at a location substantially diametrically opposed to the location of engagement between said first-mentioned tab portion and said gripping member.