Jars for Wellbore Operations
An example of an apparatus for jarring a wellbore tool from an obstruction includes four sub-assemblies in communication with three springs such that the springs may be compressed forcing the subassemblies to become adjacent to one another. When the springs are actuated, the sub-assembly units spring apart from one another force dislodging the lower most sub-assembly component from the obstruction.
This application is a continuation of application Ser. No. 11/983,979, filed on Nov. 13, 2007, which is a non-provisional application claim benefit of provisional application number 60/858,208 filed on Nov. 10, 2006.
TECHNICAL FIELDThe present invention relates in general to wellbore operations and more specifically to an apparatus and method for jarring wireline deployed tools stuck subsurface in a wellbore.
BACKGROUNDWellbore tools, such as measurement and sampling tools (e.g., logging tools) are often deployed in the wellbore via a wireline, slick line or electric line. A common problem that occurs in these operations is that the tool gets stuck in the wellbore by running into a restriction in the wellbore called a “squeeze,” an area where the wellbore has collapsed either from formation pressures or from debris sluffing off the wall of the well causing blockage called a “bridge.” When the tool can be freed by jarring the tool in an upward direction because there is no debris or restriction above the tool. When the tool becomes free it can be worked up and down to get the tool through the restriction, this is called “spudding.”
When logging is completed, the tool can become stuck when it is being pulled out of the wellbore. Sometimes the tool can be jarred upward pulling it through the restriction and sometimes it does not come free because the squeeze or bridge is too large or heavy.
If the tool becomes permanently stuck the options are to electrically burn off the weak point of the tool or pull off the weak point of the tool and do a fishing trip to retrieve the lost tool. Prior to pulling off or burning the weak point if a downward force could be applied to the tool to move it down out of the restriction the tool could be worked up and down to spud the tool up through the restriction the same way spudding the tool to get it through the restriction while running downhole.
Therefore, it is a desire of the present invention to provide a method and apparatus for freeing a wireline deployed tool by jarring in a downward direction.
SUMMARY OF THE INVENTIONAn example of a wellbore jar includes a first sub-assembly with an upper member secured the lower end of a wireline, a second sub-assembly positioned lower than the first sub-assembly and attached to the first sub-assembly. The second sub-assembly also includes a first housing, a shaft and a first spring, wherein the shaft and the spring are inside the first housing. The wellbore jar also includes a third sub-assembly including a second housing and second spring arrangement, in communication with the second sub-assembly. The wellbore assembly also includes a fourth sub-assembly attached to the third sub-assembly and also attached to a down hole tool. The fourth sub-assembly further including a third housing, and a third spring; wherein the first, second and third string are capable of storing compressive energy. The wellbore assembly also includes an actuator for releasing the stored energy in the first, second and third springs downward onto the tool.
An example of a method of dislodging a stuck tool downhole is disclosed. The method includes the steps of providing a jarring apparatus above the stuck tool. The jarring apparatus has a first, second, third and fourth sub-assembly in communication with each other. The upper end of the first sub-assembly is attached to a wireline, which imparts an upward force on the first, second and third sub-assemblies by pulling the wireline towards the surface of the well. Compressing a first, and second spring located in the second and third sub-assemblies then releasing the compressed force stored within the second and third sub-assembly downward against the fourth sub-assembly attached to the stuck tool sufficient to dislodge the stuck tool, with an imparting force on the tool attached to the upper end of the first sub-assembly.
Another example of a wellbore jar for dislodging tools downhole is disclosed. The wellbore jar includes: a first attachment means for attaching to the upper end of the apparatus to a wireline cable. There is also a second attachment means for attaching to the upper end of the tool to the lower end of the apparatus and a spring mechanism within the apparatus for storing compressional force as the length of wireline above the apparatus applies upward force on the apparatus. Also present is an actuating means for rapidly releasing the stored compressional force downward onto the tool lodged downhole.
The foregoing has outlined some of the features and technical advantages of the present invention in order that a detailed description of an example of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.
The foregoing and other features and aspects of the wellbore jar will be best understood with reference to the following detailed description of a specific embodiments of the invention, when read in conjunction with the accompanying drawings, wherein:
Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
As used herein, the terms “up” and “down”; “upper” and “lower”; “uphole” and “downhole”; and other like terms indicating relative positions to a given point or element are utilized to more clearly describe some elements of the embodiments of the invention. Commonly, the terms “up,” “upper,” “uphole,” and other like terms are meant to indicate a position that is closer to the surface along the linear distance of the borehole. It is noted that through the use of directional drilling, a wellbore may not extend straight up and down. Thus these terms describe relative positions along the wellbore.
From the foregoing detailed description of specific examples of the apparatus, it should be apparent that a wellbore drilling system and method that is novel has been disclosed. Although specific examples have been disclosed herein in some detail, this has been done solely for the purposes of describing various features and aspects of the invention, and is not intended to be limiting with respect to the scope of the invention. It is contemplated that various substitutions, alterations, and/or modifications, including but not limited to those implementation variations which may have been suggested herein, may be made to the disclosed examples without departing from the spirit and scope of the invention as defined by the appended claims which follow.
Claims
1. An apparatus for dislodging wireline deployed tools stuck downhole, comprising:
- a first sub-assembly with an upper member secured to the lower end of a wireline;
- a second sub-assembly attached to the first sub-assembly;
- the second sub-assembly comprising a first housing, a shaft, and a first spring, wherein the shaft and the first spring are inside the first housing;
- a third sub-assembly comprising a second housing and second spring arrangement; and
- a fourth sub-assembly attached to the third sub-assembly comprising a third housing, and a third spring;
- wherein the first, second and third string are capable of storing compressive energy; and
- an actuator for releasing the stored energy in the first, second and third springs downward onto the fourth sub-assembly.
2. A method of dislodging a tool stuck downhole in a wellbore, comprising the method of:
- providing a jarring apparatus above and attached to the tool, wherein the jarring apparatus has a first, second, third and fourth sub-assemblies moveably connected sequentially with each other;
- attaching an upper end of the first sub-assembly to a member upstream;
- imparting upward force on the first, second and third sub-assemblies by pulling the upstream member towards the surface of the well;
- compressing a first, and second spring located in the second and third sub-assemblies;
- releasing the compressed force stored within the second and third sub-assembly downward against the fourth sub-assembly attached to the stuck tool sufficient to dislodge the stuck tool.
3. An apparatus for dislodging tools downhole, comprising:
- a first attachment means for attaching to the upper end of the apparatus to a wireline cable;
- a second attachment means attached to the lower end of the apparatus and attached to the upper end of a downhole tool lodged downhole;
- a spring mechanism housed internally within the apparatus for storing compressional force as the length of wireline above the apparatus applies upward force on the apparatus; and
- an actuating means for rapidly releasing the stored compressional force downward onto the tool lodged downhole.
Type: Application
Filed: Jun 24, 2010
Publication Date: Oct 14, 2010
Inventor: Dwight Rose (Nederland, TX)
Application Number: 12/822,987
International Classification: E21B 31/107 (20060101);