Controlled weak point for wireline cable
First Claim
Patent Images
1. A controllable break device for use in interconnection with wireline cable and cable head comprising:
- an upper sleeve section that is secured to said cable while leading a length of cable axially therethrough;
a lower sleeve section slidingly engaged with a portion of said upper sleeve section and receiving the length of cable axially therethrough for being secured to the cable head;
an inner tube having upper and lower ends extending axially within said upper and lower sleeve sections, said inner tube carrying the cable therethrough;
mandrel means receiving the inner tube therethrough and having upper and lower ends extending between said upper and lower sleeve sections;
first shear pin means securing the mandrel means lower end to the lower sleeve section;
second shear pin means securing the inner tube upper end to said upper sleeve section; and
limit sleeve means disposed coaxial to said mandrel means and extending between the upper and lower sleeve sections, said limit sleeve means coacting selectively with said mandrel means to allow parting of said first shear pin means upon a predetermined amount of cable tension, and subsequent parting of said second shear pin means upon release of cable tension to allow separation of the upper and lower sleeve sections.
1 Assignment
0 Petitions
Accused Products
Abstract
A controllable dual weak point device for insertion in a wireline between the cable and tool. The device consists of upper and lower sections that are slidably joined together in releasable interlocking manner with the upper section secured to the cable and the lower section secured to the tool. The upper and lower sections are joined together by a concentric arrangement of central tube, mandrel and limiting sleeve which are interconnected by first and second springs and first and second shear pin arrangements, i.e., the respective first and second weak points.
38 Citations
16 Claims
-
1. A controllable break device for use in interconnection with wireline cable and cable head comprising:
-
an upper sleeve section that is secured to said cable while leading a length of cable axially therethrough; a lower sleeve section slidingly engaged with a portion of said upper sleeve section and receiving the length of cable axially therethrough for being secured to the cable head; an inner tube having upper and lower ends extending axially within said upper and lower sleeve sections, said inner tube carrying the cable therethrough; mandrel means receiving the inner tube therethrough and having upper and lower ends extending between said upper and lower sleeve sections;
first shear pin means securing the mandrel means lower end to the lower sleeve section;second shear pin means securing the inner tube upper end to said upper sleeve section; and limit sleeve means disposed coaxial to said mandrel means and extending between the upper and lower sleeve sections, said limit sleeve means coacting selectively with said mandrel means to allow parting of said first shear pin means upon a predetermined amount of cable tension, and subsequent parting of said second shear pin means upon release of cable tension to allow separation of the upper and lower sleeve sections. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A device for interconnection between a wireline cable and cable head to effect dual weak point control, comprising:
-
first sleeve means having a first end secured to said cable and having a second end; second sleeve means having a first end receiving the first sleeve means second end in slidable insertion and having a second end secured to said cable head; an inner tube carrying the cable therethrough and disposed to extend from the first sleeve means through the second sleeve means; a mandrel means including first shear pin means secured to said second sleeve means and disposed coaxially over said inner tube; first spring means compressed between said inner tube and said second sleeve means; second shear pin means securing said inner tube axially within said first sleeve means; second spring means compressed between said mandrel means and said first sleeve means first end; limit sleeve means disposed co-axially over said mandrel means within said first and second sleeve means; whereby greater than a pre-set cable tension will shear the first shear pin means to release the mandrel means and limit sleeve means for limited upward movement which allows the second sleeve means to drop a limited amount relative to said first sleeve means while said cable tension continues being applied, and removal of cable tension causes parting of the cable and complete separation of the first and second sleeve means. - View Dependent Claims (12, 13, 14, 15, 16)
-
Specification