POWDER WELD FISHING TOOL

A downhole fishing tool for retrieving an object from a wellbore includes a main body assembly, one or more nozzles configured to dispose a cladding powder on the object when the object is proximate to the tool, and one or more lenses configured to direct a laser beam at the cladding powder disposed on the object, thereby welding the fishing tool to the object such that pulling the tool in an uphole direction pulls the object along with the fishing tool.

TECHNICAL FIELD

The present disclosure relates to subterranean wells, and more specifically, to removing objects from a subterranean well.

BACKGROUND

In subsurface well drilling and completion operations, it is not uncommon for an object (such as a tool, pipe, or fragment or component thereof) to fall into, get stuck, or unintentionally be left within a wellbore of a subterranean well. This fallen, stuck, or left object is sometimes known as a fish. The retrieval of such objects from a wellbore is referred to as fishing.

SUMMARY

Certain aspects of the subject matter herein can be implemented as a downhole fishing tool for retrieving an object from a wellbore. The tool includes a main body assembly, one or more nozzles configured to dispose a cladding powder on the object when the object is proximate to the tool, and one or more lenses configured to direct a laser beam at the cladding powder disposed on the object, thereby welding the fishing tool to the object such that pulling the tool in an uphole direction pulls the object along with the fishing tool.

Certain aspects of the subject matter herein can be implemented as a system for retrieving an object from a wellbore. The system includes a fishing tool and a conveyance connected to the fishing tool. The tool includes a main body assembly, one or more nozzles configured to dispose a cladding powder on the object when the object is proximate to the tool, and one or more lenses configured to direct a laser beam at the cladding powder disposed on the object, thereby welding the fishing tool to the object. The system is configured such that, after welding the fishing tool to the object, raising the fishing tool uphole, by the conveyance, pulls the object uphole along with the tool.

Certain aspects of the subject matter herein can be implemented as a method for retrieving an object from a wellbore. The method includes lowering, by a conveyance assembly comprising an optical fiber, a fishing tool downhole within a wellbore. The fishing tool includes a main body assembly, one or more nozzles configured to dispose a cladding powder on the object when the object is proximate to the tool, and one or more lenses configured to direct a laser beam at the cladding powder disposed on the object. The method includes spraying, when the tool is proximate the object, the cladding powder on the object from the one or more nozzles, and transmitting laser light through the optical fiber to the one or more lenses, such that the lens directs a laser beam on the cladding powder, thereby welding the fishing tool to the object. After welding the fishing tool to the object, the method includes raising the fishing tool uphole by the conveyance assembly, thereby pulling the object along with the fishing tool.

DETAILED DESCRIPTION

In laser powder welding, a laser beam is directly aimed at a cladding powder disposed on a surface. The cladding powder can be an alloy or other suitable material. The heat generated by the beam melts and welds the cladding powder to a first surface and a second surface, such that welded connections can be formed between the surfaces. In some embodiments, the cladding powder is disposed on the surface by a nozzle. By laser-welding the powder layer and subsequently disposing further layers of powder on top of the welded powder and then laser-welding the added layer of powder, and then repeating the process as many times as is optimal, a strong weld including multiple welded layers can be formed.

Retrieval of a fish or other object from a wellbore can be difficult, expensive, or time consuming. In some embodiments of the present disclosure, a system, method, or apparatus includes or comprises a downhole fishing tool comprising a nozzle configured to dispose a cladding powder on the fish or other object when the object is proximate to the tool, and a lens configured to direct a laser beam at the cladding powder, thereby welding the fishing tool to the object such that, when welded, pulling the tool in an uphole direction pulls the object along with the fishing tool. In some embodiments, the tool includes a cylindrical rod or other protuberance, composed of a metallic alloy or another suitable material, extending from the tool and nozzle is configured to dispose the cladding powder on the protuberance when the protuberance is in contact with the object. In some embodiments, the lens is a conic lens configured such that the laser beam is in the form of a ring which surrounds the protuberance. In this way, heavier and/or larger fish can be retrieved than with conventional fishing tools, this increasing efficacy and safety of fishing operations.

FIG.1is a schematic illustration of a fishing system100in accordance with an embodiment of the present disclosure, comprising a powder weld fishing tool102disposed in a wellbore104drilled from a surface106into a subterranean zone107. Conveyance130can lower tool102in downhole direction (for example, towards lost downhole object120(fish) within wellbore104) and can raise tool102in an uphole direction. Conveyance130in the illustrated embodiment is a wireline supplied from a spool122, but in other embodiments conveyance130could be coiled tubing or other suitable conveyance such as a downhole tractor. Wellbore104is illustrated as a vertical well but can be a horizontal, lateral, or other well or well portion or well segment. Wellbore104can be uncased or partially or fully cased.

As described in further detail below, tool102can include a nozzle configured to dispose a cladding powder on the object when the object is proximate to the tool, and a lens configured to direct a laser beam at the cladding powder, thereby welding tool102to object120such that subsequently pulling tool102by conveyance130in an uphole direction pulls object120uphole along with tool102. Also as described further below, tool102can include one or more sensors such as a camera or other optical sensor, acoustic sensor, and/or other sensors and/or mechanisms such as rotational heads or wire feed assemblies.

System100can further include a laser source module150which is configured to transmit laser light along optical fiber160. Optical fiber160is connected to tool102and provides the laser light directed by the lens assembly. In some embodiments, optical fiber160can be integrated as a component of conveyance130. System100can further include a control module152that can receive data the sensors and transmit control signals to wire feed assemblies, rotational head tool, and/or other mechanisms, via optical fiber160or another suitable wired or wireless connection. In some embodiments, laser source module150and control module152are positioned at a surface location. In some embodiments, some or all of the components of laser source module150or control module152can be positioned downhole during some or all of the fishing process. In some embodiments, the functions of source module150and control module152can be integrated into a combined laser source and control module.

FIG.2is a schematic illustration showing further detail of laser cladding fishing tool102in accordance with an embodiment of the present disclosure. Tool102includes a main body assembly202through which optical fiber160is disposed. Main body assembly202can be configured to protect the internal components of tool102from impacts with the wellbore and other hazardous downhole conditions. Laser beam204emitted from optical fiber160is directed to first lens206of lens assembly208. First lens206can in some embodiments be a conic lens and can control the shape, size, direction, and geometry of laser beam204so as to direct laser beam204to second lens210. Second lens210can in some embodiments be a conic lens and can be configured to collimate and shape laser beam204into a ring shape (shown as laser beam ring216). In the illustrated embodiment, tool102includes a protuberance212which is a metallic cylinder extending from a downhole end of tool102, and second lens210is configured such that laser beam ring216surrounds the downhole end of protuberance212, and would be focused on a surface of an object positioned proximate to or in contact with the downhole end of protuberance212.

Tool102further includes powder nozzles214configured to spray a cladding powder from powder reservoirs217. The cladding powder can in some embodiments can be comprised of a metallic material such as Inconel or another suitable austenitic nickel-chromium-based alloy. The nozzles can be of any suitable commercially available cladding powder nozzle, and can be powered by, for example, gas pressure from a pressure conduit in conveyance130.

In some embodiments, tool102can include a gas purging system to clear the one or more nozzles in the event they become clogged. In some embodiments, tool102can include a one or more fluid nozzle assemblies219for injecting nitrogen gas or other optically clear fluid into the space between the powder nozzles and the object120to clear debris and provide an optically clear pathway for cladding powder and laser beam204to reach object120as it exits tool102. In some embodiments, the system can include one or more packers to isolate the wellbore above tool102and maintain the clear fluid in place at the interface between tool102and object120.

In operation, as described in further detail below, nozzles214can be configured to spray a cladding powder on the surface of object120or other object proximate or in contact with positioned proximate to or in contact with the downhole end of protuberance212. Laser beam ring216surrounding protuberance212can melt the powder prior to or after contact of the protuberance with the object, thereby melting the cladding powder and welding tool102to the fish. When so welded, uphole movement of tool102will pull the fish uphole along with the tool.

In the illustrated embodiment tool102includes one or more sensors220. Sensors220can include one or more cameras or other optical sensors, acoustic sensors, pressure sensors, or other suitable sensors configured to enable the operator to determine the location, distance, size, shape, and/or orientation of object120relative to tool102and the wellbore, as the tool is lowered downhole and/or during welding operations. For example, an acoustic sensor can be utilized when visibility is limited, prior to injection of the optically clear fluid for laser welding. Sensors220can be controlled by, and can transmit data to and receive data from, control module152.

FIG.3process flow diagram of a method of operating a laser cladding fishing tool in accordance with an embodiment of the present disclosure. The method ofFIG.3is described in reference to the tool and system described in reference toFIGS.1,2, and4A-4B; however, the method can be used with other suitable tools and systems.

The method begins with step302in which laser cladding fishing tool102is lowered by a conveyance130downhole within wellbore104until its downhole end is proximate object120or other downhole object, as shown inFIG.4A, guided by data from acoustic, visual, and/or other data from sensors220. At step304, as also shown inFIG.4A, cladding powder402is deposited from nozzles214onto the surface of the object, and the cladding powder melted by focusing laser beam ring216on the powder, resulting in evenly-distributed melted powder in a ring shape. For example, for the initial powder deposition of step304, tool102can be lowered towards object120until the downhole end of protuberance212a suitable distance from the surface of object120to enable the powder to be deposited and welded. The suitable distance can depend on the characteristics of the stuck object, of the nature of the fluid between the tool and the object, the nozzle type, and other factors. In some embodiments, a suitable distance can be, for example, between two and five centimeters.

At step308, the laser and nozzles are powered off and the tool is lowered further so as to contact the fish, and the melted powder forms an initial connection between the tool and the fish. As shown inFIG.4B, in the illustrated embodiment, the tool contacts the fish at the downhole end of protuberance212, forming the initial welded contact. As shown inFIG.4C, and proceeding to step310, cladding powder402is again deposited from nozzles214onto the surface of the object, and at step312the additional cladding powder is melted by focusing laser beam ring216on the powder, in the contact region around protuberance212. In this way, the tool is further bonded with the fish, with a welded seam surrounding the edge of protuberance212, forming a strong connection between the tool and the fish.

At step314, as shown inFIG.4D, the fishing tool, with the fish welded to it, is pulled uphole, pulling the fish along with the tool. At step316, the tool and fish can be retrieved from the wellbore. At the surface, the fish can be separated from the tool using conventional methods.

The term “uphole” as used herein means in the direction along a wellbore from its distal end towards the surface, and “downhole” as used herein means the direction along a wellbore from the surface towards its distal end. A downhole location means a location along a wellbore downhole of the surface.

EXAMPLES

In a first aspect, a downhole fishing tool for retrieving an object from a wellbore includes a main body assembly, one or more nozzles configured to dispose a cladding powder on the object when the object is proximate to the tool, and one or more lenses configured to direct a laser beam at the cladding powder disposed on the object, thereby welding the fishing tool to the object such that pulling the tool in an uphole direction pulls the object along with the fishing tool.

In a second aspect according to the first aspect, the tool includes a protuberance, and the tool is configured such that the protuberance is a point of contact with the object when the tool is in contact with the object and the one or more nozzles are configured to dispose the cladding powder at an interface between the protuberance and the object when the protuberance is in contact with the object.

In a third aspect according to the second aspect, the one or more lenses are configured to direct the laser beam as a ring around the protuberance.

In a fourth aspect according to any of the first to the third aspect, the protuberance is a cylindrical rod disposed on a downhole end.

In a fifth aspect according to any of the first to the fourth aspect, the fishing tool further includes one or more sensors configured to determine physical parameters indicative of the location and orientation of the object in relation to the fishing tool.

In a sixth aspect according to any of the first to the fifth aspect, the one or more sensors includes an acoustic sensor.

In a seventh aspect according to any of the first to sixth aspects, the one or more sensors includes a camera.

In an eighth aspect according to any of the first to seventh aspects, the tool further includes a nozzle assembly from which nitrogen gas can be injected into a space between the tool and the object.

In a ninth aspect, a system for retrieving an object from a wellbore includes a fishing tool and a conveyance connected to the fishing tool. The tool includes a main body assembly, one or more nozzles configured to dispose a cladding powder on the object when the object is proximate to the tool, and one or more lenses configured to direct a laser beam at the cladding powder disposed on the object, thereby welding the fishing tool to the object. The system is configured such that, after welding the fishing tool to the object, raising the fishing tool uphole, by the conveyance, pulls the object uphole along with the tool.

In a tenth aspect according to the ninth aspect, the tool includes a protuberance and the tool is configured such that the protuberance is a point of contact with the object when the tool is in contact with the object, and the one or more nozzles are configured to dispose the cladding powder at an interface between the protuberance and the object when the protuberance is in contact with the object.

In an eleventh aspect according to the tenth aspect, the one or more lenses are configured to direct the laser beam as a ring around the protuberance.

In an twelfth aspect according to the tenth or eleventh aspect, the protuberance is a cylindrical rod disposed on a downhole end of the tool.

In a thirteenth aspect according to any of the first to the twelfth aspect, the tool includes one or more sensors configured to determine physical parameters indicative of the location and orientation of the object in relation to the fishing tool.

In a fourteenth aspect according to any of the first to the thirteenth aspect, the one or more sensors includes an acoustic sensor.

In a fifteenth aspect according to any of the first to the fourteenth aspect, the one or more sensors includes a camera.

In sixteenth aspect according to any of the first to the fifteenth aspect, the tool includes a nozzle assembly from which nitrogen gas can be injected into a space between the tool and the object.

In a seventeenth aspect, a method for retrieving an object from a wellbore includes lowering, by a conveyance assembly comprising an optical fiber, a fishing tool downhole within a wellbore. The fishing tool includes a main body assembly, one or more nozzles configured to dispose a cladding powder on the object when the object is proximate to the tool, and one or more lenses configured to direct a laser beam at the cladding powder disposed on the object. The method includes spraying, when the tool is proximate the object, the cladding powder on the object from the one or more nozzles, and transmitting laser light through the optical fiber to the one or more lenses, such that the lens directs a laser beam on the cladding powder, thereby welding the fishing tool to the object. After welding the fishing tool to the object, the method includes raising the fishing tool uphole by the conveyance assembly, thereby pulling the object along with the fishing tool.

In an eighteenth aspect according to the seventeenth aspect, the tool includes a protuberance at its downhole end. Lowering the fishing tool downhole includes lowering the fishing tool such that the protuberance is in contact with the object. Spraying the cladding powder comprises spraying the cladding powder on an interface between the protuberance and the object.

In an nineteenth aspect according to the eighteenth aspect, transmitting the laser light includes directing the laser beam as a ring around the protuberance.

In a twentieth aspect according to any of the seventeenth to nineteenth aspects, the method further includes determining, by sensors on board the tool, physical parameters indicative of the location and orientation of the object in relation to the tool.