Seal for a joint or juncture – Seal for well apparatus – For below ground apparatus
Reexamination Certificate
1998-11-24
2001-03-20
Knight, Anthony (Department: 3626)
Seal for a joint or juncture
Seal for well apparatus
For below ground apparatus
C277S336000, C277S337000, C277S338000
Reexamination Certificate
active
06203020
ABSTRACT:
FIELD OF THE INVENTION
The field of this invention relates to downhole packers, particularly mechanically set packers which are used in high-temperature and high-pressure applications.
BACKGROUND OF THE INVENTION
A common problem with downhole packers is extrusion of the element into an annular gap between the packer body and the tubing or casing. The amount of extrusion is a function of the differential pressure, working temperature, and size of the gap to the casing inside diameter. The pressure and temperature rating of a packer is often determined at a time when the packing element has been pushed completely through the extrusion gap and begins to leak.
In the past, various metal rings or garter springs embedded in the elements at the top and/or bottom have been used to try to prevent extrusion of the packing elements. However, these techniques for reducing extrusion are undesirable in a mechanically set packer because the packer will not be resettable with these features. It is, therefore, desirable in a mechanically set packer that it be fully resettable in case the packer is accidentally set in the wrong location and needs to be moved.
Accordingly, the object of the present invention is to provide a configuration for the sealing element system, particularly usable in a mechanically set packer, which minimizes extrusion in high-temperature and high-pressure applications. Another objective is to accomplish a reduction of extrusion by limiting the forces applied to the top and bottom components of the packing element assembly in a packer. Another object is to configure the uppermost and/or lowermost components of a packing element system in a packer so as to discourage extrusion when set. Yet another object is to configure the surrounding gauge rings in a manner to further reduce the tendency to extrude. These objects will be readily understood by those skilled in the art by a review of the detailed description of the preferred embodiment below.
SUMMARY OF THE INVENTION
A sealing element system for a downhole packer reduces the tendency of the elements to extrude. Mechanical limits are provided to the amount of force that can be passed onto the uppermost and lowermost components of a sealing element system by providing a limit on the longitudinal compression available against a gauge ring. The gauge rings are roughened to also grab the uppermost and lowermost elements to fight the tendency to extrude. The uppermost and lowermost elements are configured with an external groove to control the way they deform into a sealing relationship with the tubing and casing so that extrusion into the gap is reduced.
REFERENCES:
patent: 1810352 (1931-06-01), Humason
patent: 2606618 (1952-08-01), Page
patent: 2612953 (1952-10-01), Morgan et al.
patent: 2799348 (1957-07-01), Page
patent: 3339637 (1967-09-01), Holden
patent: 3569608 (1971-03-01), Ance
patent: 4321015 (1982-03-01), Roeder
patent: 4791992 (1988-12-01), Greenlee et al.
Advertisement for Halliburton Perma-Lach Packer, 1 page, date unknown.
Advertisement for Arrowset I-X Retrievable Production Packer, 1 page, date unknown.
Doane James C.
Mireles, Jr. Hector H.
Baker Hughes Incorporated
Duane Morris & Heckscher LLP
Knight Anthony
Peavey Enoch E.
LandOfFree
Downhole packer with element extrusion-limiting device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Downhole packer with element extrusion-limiting device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Downhole packer with element extrusion-limiting device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2504044