Patent Application
20120048553
Fishing is a well known vernacular term in industries involved in subterranean drilling and completion activities. Fishing related to the removal from a borehole of a tool that has been dropped or become stuck. Clearly downhole operations of any type can be significantly impeded by a tool in the borehole that does not belong there and hence it is in the interest of operators to remove such “fish” from the borehole.
Over the years the industry has produced many different tools and methods for fishing but it is well known to those in the industry that the possibilities of parameters of a particular fish are endless and accordingly the industry is always receptive to new tools and methods for fish retrieval.
Disclosed herein is a fishing tool that includes a grapple and an exciter in vibration transmissive communication with the grapple.
Further disclosed herein is a method for retrieving a stuck fish in a borehole that includes running a fishing tool that includes a grapple and an exciter in vibration transmissive communication with the grapple into a borehole having a stuck fish. The method further includes engaging the fish and actuating the exciter after which the fish is vibrated.
Referring now to the drawings wherein like elements are numbered alike in the several Figures:
Referring to
Schematically illustrated adjacent the grapple 16 is an exciter 18 capable of providing excitation to the fishing tool 14 to enhance fish recovery. The exciter 18 will be addressed further hereunder with reference to
Referring now to
The rod 26 when disposed in a flowing fluid 28, will tend to develop vortices that form and release from each side of the rod 26. The formation of a vortex on one side of the rod 26 tends to pull the rod 26 in that direction and also pull flow from the other side of the rod 26 into the vortex. The pulled in fluid will then tend to cut off the first formed vortex as the second formed vortex grows. With growth of the second formed vortex, the fluid will tend to pull the rod 26 in the direction of the second vortex. Fluid dynamics of the system will be periodic and hence cause the movement of the rod 26 to become vibratory. The vibrations will be primarily transverse to the rod 26. The vibrations created will be proportionally to the Reynolds number of the fluid flowing past the rod 26 and have a magnitude that is sufficiently high to assist in freeing a fish 12 by vibrating the fish 12. The vibration of the fish 12 occurs because the housing 22 is coupled to the grapple 16, which then is in solid communication with the fish 12 (since the fish must be strongly enough held to make the trip out of the borehole). The fish 12 then vibrates at the same frequency and near the same magnitude as the rod 26. Vibrations assist in loosening a stuck fish 12, hence the prior art usage of jars to vibrate the string 20.
In the embodiment of
All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other (e.g., ranges of “up to 25 wt. %, or, more specifically, 5 wt. % to 20 wt. %”, is inclusive of the endpoints and all intermediate values of the ranges of “5 wt. % to 25 wt. %,” etc.). “Combination” is inclusive of blends, mixtures, alloys, reaction products, and the like. Furthermore, the terms “first,” “second,” and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms “a” and “an” and “the” herein do not denote a limitation of quantity, and are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The suffix “(s)” as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including one or more of that term (e.g., the film(s) includes one or more films). Reference throughout the specification to “one embodiment”, “another embodiment”, “an embodiment”, and so forth, means that a particular element (e.g., feature, structure, and/or characteristic) described in connection with the embodiment is included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various embodiments.
While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.
