US20200284104A1 - Flexible Tubular Sub, and Method of Running a Tool String Into a Wellbore - Google Patents
Flexible Tubular Sub, and Method of Running a Tool String Into a Wellbore Download PDFInfo
- Publication number
- US20200284104A1 US20200284104A1 US16/800,395 US202016800395A US2020284104A1 US 20200284104 A1 US20200284104 A1 US 20200284104A1 US 202016800395 A US202016800395 A US 202016800395A US 2020284104 A1 US2020284104 A1 US 2020284104A1
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- wellbore
- sub
- outer diameter
- tool string
- flexible tubular
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Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/042—Threaded
- E21B17/0423—Threaded with plural threaded sections, e.g. with two-step threads
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/042—Threaded
- E21B17/0426—Threaded with a threaded cylindrical portion, e.g. for percussion rods
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/20—Flexible or articulated drilling pipes, e.g. flexible or articulated rods, pipes or cables
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/11—Perforators; Permeators
- E21B43/116—Gun or shaped-charge perforators
Definitions
- the present disclosure relates to the field of hydrocarbon recovery operations. More specifically, the invention relates to a flexible tubular body that may be used for running a tool string into a deviated wellbore. Further still, the invention relates to a perforating gun assembly having a flexible tubular sub, enabling the perforating gun assembly to traverse the transition section of a horizontally-completed wellbore.
- a near-vertical wellbore is formed through the earth using a drill bit urged downwardly at a lower end of a drill string. After drilling to a predetermined depth, the drill string and bit are removed and the wellbore is lined with a string of casing. An annular region is thus formed between the string of casing and the formation penetrated by the wellbore.
- a cementing operation is conducted in order to fill or “squeeze” the annular region with cement along part or all of the length of the wellbore.
- the combination of cement and casing strengthens the wellbore and facilitates the zonal isolation of aquitards and hydrocarbon-producing zones behind the casing.
- strings of casing having progressively smaller outer diameters will be cemented into the wellbore. These will include a string of surface casing, one or more strings of intermediate casing, and finally a production casing. The process of drilling and then cementing progressively smaller strings of casing is repeated until the well has reached total depth.
- the final string of casing is a liner, that is, a string of casing that is not tied back to the surface.
- the horizontal “leg” of each of these wellbores now often exceeds a length of one mile, and sometimes two or even three miles. This significantly multiplies the wellbore exposure to a target hydrocarbon-bearing formation.
- the horizontal leg will typically include production casing.
- FIG. 1 is a side, cross-sectional view of a wellbore 100 , in one embodiment.
- the wellbore 100 has been completed horizontally, that is, it has a horizontal leg 156 .
- the wellbore 100 defines a bore 10 that has been drilled from an earth surface 105 into a subsurface 110 .
- the wellbore 100 is formed using any known drilling mechanism, but preferably using a land-based rig or an offshore drilling platform (not shown).
- the wellbore 100 is completed with a first string of casing 120 , sometimes referred to as surface casing.
- the wellbore 100 is further completed with a second string of casing 130 , typically referred to as an intermediate casing.
- a second intermediate string of casing is shown at 140 .
- the wellbore 100 is finally completed with a string of production casing 150 .
- the production casing 150 extends from the surface 105 down to a subsurface formation, or “pay zone” 115 .
- the wellbore is completed horizontally, meaning that the horizontal “leg” 156 is formed.
- the leg 156 includes a heel 153 and a toe 154 .
- the heel 153 may be referred to as a transition section, while the toe 154 defines the end (or “TD”) of the wellbore 100 .
- the production casing 150 will also extend along the horizontal leg 156 .
- the cement (or cement matrix) 125 serves to isolate the wellbore 100 from freshwater zones and potentially porous formations around the casing string 120 .
- the annular regions around the intermediate casing strings 130 , 140 are also filled with cement 135 , 145 .
- the annular region around the production casing 150 is filled with cement 155 .
- the cement 135 , 145 , 155 is optionally only placed behind the respective casing strings 130 , 140 , 150 up to the lowest joints of the immediately surrounding casing strings.
- a non-cemented annular area 132 is typically preserved above the cement matrix 135
- a non-cemented annular area 152 is frequently preserved above the cement matrix 155 .
- the casing 150 along the horizontal section 156 undergoes a process of perforating and fracturing (or in some cases perforating and acidizing). Due to the very long lengths of new horizontal wells, the perforating and formation treatment process is typically carried out in stages.
- a perforating gun assembly (shown schematically at 114 ) is pumped down towards the end of the horizontal leg 156 at the end of a wireline 118 .
- the perforating gun assembly 114 will include a series of perforating guns, with each gun having sets of charges ready for detonation.
- the perforating gun assembly 200 is pumped down towards the end 154 of the wellbore 100 .
- the charges associated with one of the perforating guns are detonated and perforations are “shot” into the casing 150 .
- a perforating gun has explosive charges, typically shaped, hollow or projectile charges, which are ignited to create holes in the casing (and, if present, the surrounding cement) 150 and to pass at least a few inches and possibly several feet into the formation 115 .
- the perforations (not shown) create fluid communication with the surrounding formation 115 so that hydrocarbon fluids can flow into the casing 150 and up to the surface 105 .
- the operator will fracture (or otherwise stimulate) the formation 115 through the perforations (not shown). This is done by pumping treatment fluids into the formation 115 at a pressure above a formation parting pressure.
- the wireline 118 will be raised and the perforating gun assembly 114 will be positioned at a new location (or “depth”) along the horizontal leg 156 .
- a plug 112 is set below the perforating gun assembly 114 and new shots are fired in order to create a new set of perforations (not shown).
- treatment fluid is again pumped into the wellbore 100 and into the formation 115 at a pressure above the formation parting pressure. In this way, a second set of fractures is formed away from the wellbore.
- the process of setting a plug, perforating the casing, and fracturing the formation is repeated in multiple stages until the wellbore 100 has been completed.
- FIG. 2 is a side view of an illustrative perforating gun assembly 200 , or at least a portion of an assembly.
- the perforating gun assembly 200 comprises a string of perforating guns 210 .
- Each perforating gun 210 represents various components. These typically include a “gun barrel” 212 which serves as an outer tubular housing. An uppermost gun barrel 212 is supported by an electric wire (or “e-line”) 240 that extends from the surface and that delivers electrical energy down to the tool string 200 . Each perforating gun 210 also includes an explosive initiator, or “detonator” (not shown) that receives electrical energy. In addition, each perforating gun 210 comprises a detonating cord (also not shown). The detonating cord contains an explosive compound that is detonated by the detonator. The detonator, in turn, initiates one or more shots, or “shaped charges.” The charges are held in an inner tube, referred to as a carrier tube, for security and discharge through openings 215 in the selected perforating gun 210 .
- a carrier tube for security and discharge through openings 215 in the selected perforating gun 210 .
- the perforating gun assembly 200 also optionally includes short centralizer subs 220 .
- tandem subs 225 are used to connect the gun barrels end-to-end.
- Each tandem sub 225 comprises a metal threaded connector placed between the gun barrels 210 .
- the gun barrels 210 will have female-by-female threaded ends while the tandem sub 225 has opposing male threaded ends.
- An insulated connection member 230 connects the e-line 240 to the uppermost perforating gun 210 .
- the perforating gun assembly 200 with its long string of gun barrels (the housings 212 of the perforating guns 210 ) is carefully assembled at the surface 105 , and then lowered into the wellbore 10 at the end of the e-line 240 and connection member 230 .
- the e-line 240 extends upward to a control interface (not shown) located at the surface 105 .
- An operator of the control interface may send electrical signals to the perforating gun assembly 200 for detonating the shaped charges through the openings and for creating the perforations in the casing 150 .
- the setting tool 160 and the perforating gun assembly 200 are taken out of the well 100 and a ball (not shown) is dropped into the wellbore 100 to close the plug 112 .
- a fluid e.g., water, water and sand, fracturing fluid, etc.
- a pumping system not shown
- the above operations may be repeated multiple times for perforating and/or fracturing the casing 150 at multiple locations, corresponding to different stages of the well.
- multiple plugs may be used for isolating the respective stages from each other during the perforating phase and/or fracturing phase.
- the plugs are drilled out and the wellbore is cleaned using a circulating tool.
- the perforating gun assembly 200 and its long string of gun barrels is not a particularly flexible tool string. This creates a problem for the operator when trying to pump the perforating gun assembly 200 through the heel 153 of a horizontally formed wellbore (or across any deviated section). This problem is becoming more severe as drilling companies form wells having tighter transition sections. Not only that, but the horizontal leg 156 can itself sometimes undulate and cork screw, creating somewhat tight areas for a gun barrel string.
- a flexible tubular sub is provided herein.
- the tubular sub comprises a cylindrical body having a first end and an opposing second end.
- Each of the first and second ends comprises threads.
- each of the first and second ends has a first outer diameter.
- the flexible tubular sub also comprises an elongated shaft that is part of the cylindrical body.
- the shaft resides between the first and second ends, and has a second outer diameter that is smaller than the first outer diameter. This serves to reduce a moment of inertia for the flexible sub.
- the tubular sub also has an elongated bore.
- the bore extends between the first and second ends and is dimensioned to receive an electrical wire or data cable.
- the flexible tubular sub further includes a pair of transition sections.
- the transition sections reside between the shaft and each of the opposing first and second ends. Thus, a pair of transition sections is actually provided.
- the shaft of the tubular sub is fabricated from high strength steel, titanium, beryllium copper, or a metal alloy thereof.
- the shaft represents between 40% and 70% of the end-to-end length of the tubular sub.
- the shaft, or more specifically the material comprising the shaft has a modulus of elasticity that allows the shaft to deform as it is pumped across or pulled out of the heel of a wellbore, and allowing the shaft to return to its original shape.
- either or both of the threads at the first and second ends comprises female threads, with the female threads being configured to threadedly connect to an end of a perforating gun through tandem subs.
- a flexible tool string is also provided herein.
- the tool string comprises a first cylindrical wellbore tool having a rigid housing and a second cylindrical wellbore tool also having a rigid housing.
- the tool string also includes a flexible tubular sub.
- the tubular sub is designed in accordance with the flexible tubular sub described above in its various embodiments.
- the tubular sub resides between the first cylindrical wellbore tool and the second cylindrical wellbore tool.
- each of the first and second wellbore tools is a perforating gun.
- the tool string is a perforating gun assembly.
- the outer diameter of each perforating gun is formed by a respective gun barrel housing.
- the threads at each of the first and second ends of the tubular sub comprises female threads configured to threadedly connect to an end of a perforating gun.
- the connection is made through opposing tandem subs.
- FIG. 1 is a side, cross-sectional view of a wellbore, in one embodiment.
- the wellbore has been completed with an elongated horizontal section.
- FIG. 2 is a side view of an illustrative string of gun barrels forming a perforating gun assembly.
- the perforating gun assembly represents an illustrative rigid tool string.
- FIG. 3A is a perspective view of a flexible tubular sub of the present invention, in one embodiment.
- FIG. 3B is a cut-away view of the flexible tubular sub of FIG. 3A . Here, an inner bore of the tubular sub is shown.
- FIG. 4 is a side view of the flexible tubular sub of FIG. 3A .
- the tubular sub is shown between opposing tandem subs of a perforating gun assembly.
- hydrocarbon refers to an organic compound that includes primarily, if not exclusively, the elements hydrogen and carbon. Hydrocarbons may also include other elements, such as, but not limited to, halogens, metallic elements, nitrogen, carbon dioxide, and/or sulfuric components such as hydrogen sulfide.
- produced fluids refer to liquids and/or gases removed from a subsurface formation, including, for example, an organic-rich rock formation.
- Produced fluids may include both hydrocarbon fluids and non-hydrocarbon fluids.
- Production fluids may include, but are not limited to, oil, natural gas, pyrolyzed shale oil, synthesis gas, a pyrolysis product of coal, nitrogen, carbon dioxide, hydrogen sulfide and water.
- fluid refers to gases, liquids, and combinations of gases and liquids, as well as to combinations of gases and solids, combinations of liquids and solids, and combinations of gases, liquids, and solids.
- subsurface refers to geologic strata occurring below the earth's surface.
- the term “formation” refers to any definable subsurface region regardless of size.
- the formation may contain one or more hydrocarbon-containing layers, one or more non-hydrocarbon containing layers, an overburden, and/or an underburden of any geologic formation.
- a formation can refer to a single set of related geologic strata of a specific rock type, or to a set of geologic strata of different rock types that contribute to or are encountered in, for example, without limitation, (i) the creation, generation and/or entrapment of hydrocarbons or minerals, and (ii) the execution of processes used to extract hydrocarbons or minerals from the subsurface region.
- wellbore refers to a hole in the subsurface made by drilling or insertion of a conduit into the subsurface.
- a wellbore may have a substantially circular cross section, or other cross-sectional shapes.
- the term “well,” when referring to an opening in the formation, may be used interchangeably with the term “wellbore.”
- FIG. 3A is a cross-sectional view of a flexible tubular sub 300 of the present invention, in one embodiment.
- FIG. 3B is a cross-sectional view of the flexible tubular sub 300 of FIG. 3A .
- the tubular sub 300 will be discussed with reference to FIGS. 3A and 3B together.
- the tubular sub 300 is designed to reside along an otherwise rigid string of tools, such as the gun barrel assembly 200 of FIG. 2 .
- the tubular sub 300 operates to reduce bending stress and drag on the tool string 200 while it is being pumped into or pulled out of a wellbore 100 . This is of particular benefit when the string of tools is being passed across the transition section, or “heel,” 153 of a horizontally completed wellbore.
- the tubular sub 300 defines a generally cylindrical body having a first end 312 and an opposing second end 314 .
- Each end 312 , 314 represents a threaded connector. Threads are shown at 311 .
- each end 312 , 314 defines female threads 311 for receiving male threads from an adjoining wellbore tool or connector sub.
- each of the first and second ends 312 , 314 has a first outer diameter.
- each coupling 317 extends inward from the threads about 1 to 4 inches.
- Flat surfaces (or “flats”) 313 may be placed around the couplings 317 for use in torqueing the sub 300 onto an adjoining tandem sub (as shown at 225 of FIG. 4 ).
- the tubular sub 300 also comprises an elongated shaft 316 .
- the shaft 316 extends between the first 312 and the second ends 314 forming a part of the cylindrical body.
- the shaft 316 has a second outer diameter that is smaller than the first outer diameter. This serves to reduce a moment of inertia for the flexible tubular sub 300 . It is understood that the smaller the outer diameter of the shaft 316 , the better it will flex when passing across the deviated section of a wellbore 100 . The O.D. minimum is limited by the bending stress applied when picking up the tool string 200 from horizontal to vertical.
- the shaft 316 and opposing couplings 317 may be fabricated from a high strength steel.
- the shaft 316 and couplings 317 may comprise titanium, beryllium or copper. Combinations of these materials, forming an alloy, may also be used.
- the shaft 316 or more specifically the material comprising the shaft 316 , has a modulus of elasticity that allows the shaft 316 to deform as it is pumped across or pulled out of the heel 153 of a wellbore, and allowing the shaft 316 to return to its original shape.
- the tubular sub 300 also comprises a pair of transition sections 318 .
- Each transition section 318 resides between the shaft 316 and an opposing first 312 or second end 314 .
- Each transition section 318 is about 1 to 4 inches in length.
- the shaft 316 represents 40% to 70% inclusive of the end-to-end length of the tubular sub 300 .
- the tubular sub 300 is configured to slidably receive a data cable or an electrical wire (not shown) for the transmission of signals, data or power.
- the cylindrical body making up the sub 300 has a bore 315 configured to receive the cable or wires. A smaller I.D. is preferred to closely hold the cable or wires.
- the flexible tubular sub 300 is threadedly placed between two perforating guns, such as perforating guns 210 of FIG. 2 .
- Traditional gun barrels (the rigid housings 212 of the perforating guns 210 ) are female-by-female, with the connecting tandem subs 225 being male-by-male, meaning that each end has male threads.
- the flexible sub 300 may be used as an in-line replacement for any typical gun barrel by using the same female-by-female threaded ends.
- the same ends 312 , 314 of the flexible sub 300 may be made with any combination of threads, such as male-by-female.
- the operator may replace both a gun barrel and a sub together and then use a flexible sub 300 having male-by-female threaded ends.
- the female-by-female design no additional insulators, conductors, contact pins, or springs are required as the design may utilize the existing gun wire and bulkheads to pass electrical continuity through the bore 315 downhole as the replaced gun barrel would.
- FIG. 4 is a side view of the flexible tubular sub 300 of FIG. 3A .
- the tubular sub 300 is shown between opposing tandem subs 225 of a perforating gun assembly (such as assembly 200 of FIG. 2 ).
- the tandem subs 225 are shown in greater illustrative detail, and are exploded away from the tubular sub 300 , revealing male threaded ends 227 .
- the male threaded ends 227 thread directly into respective female threaded ends 312 , 314 (or couplings 317 ) of the flexible sub 300 .
- perforating guns 210 are shown exploded away from opposing ends of the tubular sub 300 .
- the tubular sub 300 is connected to the perforating guns 210 by means of the tandem subs 225 .
- Each tandem sub 225 has a male threaded end 227 .
- One male end 227 of a tandem sub 225 connects to a female end, e.g., end 312 , of the tubular sub 300 , while the other male end 227 of the tandem sub 225 connects to a female end 217 of the perforating gun 210 .
- the tubular sub 300 serves as a flexible, “blank” perforating gun in a perforating gun assembly.
- the flexible sub 300 preferably has a length that is between one and five times the value of the first outer diameter
- the flexible sub 300 has an overall length that matches or approximates the length of the gun barrels 210 used in the tool string 200 .
- the flexible sub 300 will also be 16 inches from end 312 to end 314 .
- the length of the tubular sub 300 may be longer or shorter than the gun barrels 210 .
- the longer the length of the flexible sub 300 the more flex/deviation the sub 300 will offer, allowing the operator to navigate through more highly deviated wellbores.
- the flexible tubular sub 300 is between 2 and 12 inches in length, and more preferably between 5 and 10 inches in length.
- the internal bore 315 of the flexible sub 300 serves as an internal chamber for holding wires and/or data cables en route to a next perforating gun downhole.
- the wires or data cables extend through the perforating gun assembly, transmitting detonation signals one gun at a time, from the bottom up.
- the electronics inside the tandem sub 225 initiate the detonation of the upstream perforating gun 210 .
- certain of the electronics are stored in the tandem sub 225 rather than in the perforating gun housing 212 .
- the adjoining tandem sub 225 holds a seal mechanism (e.g., adapter and dart or dart puck and dart) (not shown) that is designed to pressure seal the downstream end of the bore of the sub 225 .
- a seal mechanism e.g., adapter and dart or dart puck and dart
- Such seal mechanisms are provided in U.S. Ser. No. 15/808,290 entitled “Switch Sub With Two-Way Sealing Features and Method,” the entirety of which is incorporated herein by reference.
- the term “puck” is used to mean an element having a certain surface that is used to cover an opening in a switch sub.
- the puck may have any shape and/or size as long as the features discussed later can be implemented in such element.
- the puck may be made of any appropriate material.
- the puck may be a slab of metal.
- the term “dart” is used to mean an element that can partially enter inside a conduit formed in the puck. Under normal conditions, the dart can enter only partially inside the conduit. However, under increased pressure, the dart can deform and enter more inside the conduit.
- the dart may have any shape and/or size as long as it fulfils the features noted above.
- the dart may be a projectile.
- the debris from the gun assembly, the wellbore fluid, and/or pressure wave produced by the detonation will not enter the internal chamber 315 of the upstream flexible sub 300 and damage the wires and/or data cables upstream.
- this arrangement is optional.
- a method of running a tool string into a wellbore is also provided herein.
- the method first includes providing a wellbore.
- the wellbore will have a deviated section, such as a horizontal section having a heel and a toe.
- the method further comprises running a tool string into the wellbore.
- the tool string has a first cylindrical wellbore tool comprising a rigid housing, and a second cylindrical wellbore tool also comprising a rigid housing.
- each wellbore tool is a perforating gun and the rigid housings are gun barrels.
- the tool string also includes a flexible tubular sub defining a cylindrical body.
- the flexible sub may be in accordance with the sub 300 described above in its various embodiments.
- the flexible tubular sub may comprise:
- the method also comprises passing the tool string through the deviated section.
- running the tool string into the wellbore and passing the tool string through the deviated section comprises pumping the tool string downhole at the end of a wireline, using hydraulic pressure.
- each of the first and second wellbore tools is a perforating gun 210 .
- the tool string is a perforating gun assembly that is run into the wellbore 100 at the end of an electric line 240 .
- the outer diameter of each perforating gun is formed by a respective gun barrel housing and represents the O.D. of the “adjacent wellbore tool.”
- the threads at each of the first and second ends of the flexible tubular sub comprises female threads configured to threadedly connect to an end of a tandem sub.
- Each tandem sub comprises male-by-male ends, with a first male end being threadedly connected to an end of the flexible tubular sub, and a second male end being threadedly connected to an end of a perforating gun (or, more particularly, the housing of the perforating gun).
- the tandem subs 225 become a means for threadedly connecting the flexible sub 300 to adjoining perforating guns 210 .
- each tandem sub 225 is threaded to a perforating gun 210 and encases a bulkhead assembly.
- the bulkhead assembly includes a contact pin that transmits electrical signals from gun barrel 210 to gun barrel 210 .
- the flexible sub 300 will ideally be placed central to the tool string 200 .
- multiple flexible subs 300 may be used in the tool string 200 , in which case one flexible sub 300 would be placed at or near the top of the tool string 200 and one would be placed near the middle of the tool string 200 .
- An additional flexible sub 300 may be added near the bottom of the tool string.
- a flexible joint is provided herein.
- the flexible joint is an improvement over known knuckle joints which can be expensive, complex and prone to failure.
- variations of the tool and of methods for using the tool within a wellbore may fall within the spirit of the claims, below. It will be appreciated that the inventions are susceptible to other modifications, variations and changes without departing from the spirit thereof.
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Abstract
Description
- This application claims the benefit of U.S. Ser. No. 62/814,129 filed Mar. 5, 2019. That application is entitled “Flexible Tubular Sub, and Method of Running a Tool String Into a Wellbore.”
- Not applicable.
- Not applicable.
- This section is intended to introduce various aspects of the art, which may be associated with exemplary embodiments of the present disclosure. This discussion is believed to assist in providing a framework to facilitate a better understanding of particular aspects of the present disclosure. Accordingly, it should be understood that this section should be read in this light, and not necessarily as admissions of prior art.
- The present disclosure relates to the field of hydrocarbon recovery operations. More specifically, the invention relates to a flexible tubular body that may be used for running a tool string into a deviated wellbore. Further still, the invention relates to a perforating gun assembly having a flexible tubular sub, enabling the perforating gun assembly to traverse the transition section of a horizontally-completed wellbore.
- In the drilling of an oil and gas well, a near-vertical wellbore is formed through the earth using a drill bit urged downwardly at a lower end of a drill string. After drilling to a predetermined depth, the drill string and bit are removed and the wellbore is lined with a string of casing. An annular region is thus formed between the string of casing and the formation penetrated by the wellbore.
- A cementing operation is conducted in order to fill or “squeeze” the annular region with cement along part or all of the length of the wellbore. The combination of cement and casing strengthens the wellbore and facilitates the zonal isolation of aquitards and hydrocarbon-producing zones behind the casing.
- In connection with the completion of the wellbore, several strings of casing having progressively smaller outer diameters will be cemented into the wellbore. These will include a string of surface casing, one or more strings of intermediate casing, and finally a production casing. The process of drilling and then cementing progressively smaller strings of casing is repeated until the well has reached total depth. In some instances, the final string of casing is a liner, that is, a string of casing that is not tied back to the surface.
- Within the last two decades, advances in drilling technology have enabled oil and gas operators to “kick-off” and steer wellbore trajectories from a vertical orientation to a horizontal orientation. The horizontal “leg” of each of these wellbores now often exceeds a length of one mile, and sometimes two or even three miles. This significantly multiplies the wellbore exposure to a target hydrocarbon-bearing formation. The horizontal leg will typically include production casing.
-
FIG. 1 is a side, cross-sectional view of awellbore 100, in one embodiment. Thewellbore 100 has been completed horizontally, that is, it has ahorizontal leg 156. Thewellbore 100 defines abore 10 that has been drilled from anearth surface 105 into asubsurface 110. Thewellbore 100 is formed using any known drilling mechanism, but preferably using a land-based rig or an offshore drilling platform (not shown). - The
wellbore 100 is completed with a first string of casing 120, sometimes referred to as surface casing. Thewellbore 100 is further completed with a second string ofcasing 130, typically referred to as an intermediate casing. In deeper wells, that is wells completed below 7,500 feet, at least two intermediate strings of casing will be used. InFIG. 1A , a second intermediate string of casing is shown at 140. - The
wellbore 100 is finally completed with a string ofproduction casing 150. In the view ofFIG. 1 , theproduction casing 150 extends from thesurface 105 down to a subsurface formation, or “pay zone” 115. Where the wellbore is completed horizontally, meaning that the horizontal “leg” 156 is formed. Theleg 156 includes aheel 153 and atoe 154. Theheel 153 may be referred to as a transition section, while thetoe 154 defines the end (or “TD”) of thewellbore 100. Theproduction casing 150 will also extend along thehorizontal leg 156. - It is observed that the annular region around the surface casing 120 is filled with cement 125. The cement (or cement matrix) 125 serves to isolate the
wellbore 100 from freshwater zones and potentially porous formations around the casing string 120. - The annular regions around the
intermediate casing strings cement production casing 150 is filled withcement 155. However, thecement respective casing strings cement matrix 135, and a non-cementedannular area 152 is frequently preserved above thecement matrix 155. - In order to enhance the recovery of hydrocarbons, particularly in low-
permeability formations 115, thecasing 150 along thehorizontal section 156 undergoes a process of perforating and fracturing (or in some cases perforating and acidizing). Due to the very long lengths of new horizontal wells, the perforating and formation treatment process is typically carried out in stages. - In one method, a perforating gun assembly (shown schematically at 114) is pumped down towards the end of the
horizontal leg 156 at the end of a wireline 118. The perforatinggun assembly 114 will include a series of perforating guns, with each gun having sets of charges ready for detonation. - In operation, the
perforating gun assembly 200 is pumped down towards theend 154 of thewellbore 100. The charges associated with one of the perforating guns are detonated and perforations are “shot” into thecasing 150. Those of ordinary skill in the art will understand that a perforating gun has explosive charges, typically shaped, hollow or projectile charges, which are ignited to create holes in the casing (and, if present, the surrounding cement) 150 and to pass at least a few inches and possibly several feet into theformation 115. The perforations (not shown) create fluid communication with the surroundingformation 115 so that hydrocarbon fluids can flow into thecasing 150 and up to thesurface 105. - After perforating, the operator will fracture (or otherwise stimulate) the
formation 115 through the perforations (not shown). This is done by pumping treatment fluids into theformation 115 at a pressure above a formation parting pressure. - After the fracturing operation is complete, the wireline 118 will be raised and the perforating
gun assembly 114 will be positioned at a new location (or “depth”) along thehorizontal leg 156. Aplug 112 is set below the perforatinggun assembly 114 and new shots are fired in order to create a new set of perforations (not shown). Thereafter, treatment fluid is again pumped into thewellbore 100 and into theformation 115 at a pressure above the formation parting pressure. In this way, a second set of fractures is formed away from the wellbore. - The process of setting a plug, perforating the casing, and fracturing the formation is repeated in multiple stages until the
wellbore 100 has been completed. - In order to provide perforations for the multiple stages without having to pull the perforating gun after every detonation, the perforating gun assembly employs multiple guns in series.
FIG. 2 is a side view of an illustrativeperforating gun assembly 200, or at least a portion of an assembly. The perforatinggun assembly 200 comprises a string of perforatingguns 210. - Each perforating
gun 210 represents various components. These typically include a “gun barrel” 212 which serves as an outer tubular housing. Anuppermost gun barrel 212 is supported by an electric wire (or “e-line”) 240 that extends from the surface and that delivers electrical energy down to thetool string 200. Each perforatinggun 210 also includes an explosive initiator, or “detonator” (not shown) that receives electrical energy. In addition, each perforatinggun 210 comprises a detonating cord (also not shown). The detonating cord contains an explosive compound that is detonated by the detonator. The detonator, in turn, initiates one or more shots, or “shaped charges.” The charges are held in an inner tube, referred to as a carrier tube, for security and discharge throughopenings 215 in the selected perforatinggun 210. - The perforating
gun assembly 200 also optionally includesshort centralizer subs 220. In addition,tandem subs 225 are used to connect the gun barrels end-to-end. Eachtandem sub 225 comprises a metal threaded connector placed between the gun barrels 210. Typically, thegun barrels 210 will have female-by-female threaded ends while thetandem sub 225 has opposing male threaded ends. - An
insulated connection member 230 connects the e-line 240 to the uppermost perforatinggun 210. The perforatinggun assembly 200 with its long string of gun barrels (thehousings 212 of the perforating guns 210) is carefully assembled at thesurface 105, and then lowered into thewellbore 10 at the end of the e-line 240 andconnection member 230. The e-line 240 extends upward to a control interface (not shown) located at thesurface 105. An operator of the control interface may send electrical signals to the perforatinggun assembly 200 for detonating the shaped charges through the openings and for creating the perforations in thecasing 150. - After the
casing 150 has been perforated and at least oneplug 112 has been set, thesetting tool 160 and the perforatinggun assembly 200 are taken out of the well 100 and a ball (not shown) is dropped into thewellbore 100 to close theplug 112. When theplug 112 is closed, a fluid, (e.g., water, water and sand, fracturing fluid, etc.) is pumped by a pumping system (not shown), down thewellbore 100 for fracturing purposes. - The above operations may be repeated multiple times for perforating and/or fracturing the
casing 150 at multiple locations, corresponding to different stages of the well. Note that in this case, multiple plugs may be used for isolating the respective stages from each other during the perforating phase and/or fracturing phase. When all stages are completed, the plugs are drilled out and the wellbore is cleaned using a circulating tool. - Those of ordinary skill in the art will appreciate that the perforating
gun assembly 200 and its long string of gun barrels (thehousings 212 of the perforating guns 210) is not a particularly flexible tool string. This creates a problem for the operator when trying to pump the perforatinggun assembly 200 through theheel 153 of a horizontally formed wellbore (or across any deviated section). This problem is becoming more severe as drilling companies form wells having tighter transition sections. Not only that, but thehorizontal leg 156 can itself sometimes undulate and cork screw, creating somewhat tight areas for a gun barrel string. - Therefore, a need exists for a perforating gun assembly having flexible subs spaced between the gun barrels to reduce bending stress and drag in the wellbore. Further, a need exists for a flexible tubular sub that may be threadedly connected between gun barrels (or other rigid wellbore tools), such as by connection to tandem subs. Still further, a need exists for a method of running a perforating gun assembly into a wellbore using one or more flexible tubular subs.
- A flexible tubular sub is provided herein. In one aspect, the tubular sub comprises a cylindrical body having a first end and an opposing second end. Each of the first and second ends comprises threads. In addition, each of the first and second ends has a first outer diameter.
- The flexible tubular sub also comprises an elongated shaft that is part of the cylindrical body. The shaft resides between the first and second ends, and has a second outer diameter that is smaller than the first outer diameter. This serves to reduce a moment of inertia for the flexible sub.
- The tubular sub also has an elongated bore. The bore extends between the first and second ends and is dimensioned to receive an electrical wire or data cable.
- The flexible tubular sub further includes a pair of transition sections. The transition sections reside between the shaft and each of the opposing first and second ends. Thus, a pair of transition sections is actually provided.
- In one aspect, the shaft of the tubular sub is fabricated from high strength steel, titanium, beryllium copper, or a metal alloy thereof. Preferably, the shaft represents between 40% and 70% of the end-to-end length of the tubular sub. Preferably, the shaft, or more specifically the material comprising the shaft, has a modulus of elasticity that allows the shaft to deform as it is pumped across or pulled out of the heel of a wellbore, and allowing the shaft to return to its original shape.
- Preferably, either or both of the threads at the first and second ends comprises female threads, with the female threads being configured to threadedly connect to an end of a perforating gun through tandem subs.
- A flexible tool string is also provided herein. The tool string comprises a first cylindrical wellbore tool having a rigid housing and a second cylindrical wellbore tool also having a rigid housing.
- The tool string also includes a flexible tubular sub. The tubular sub is designed in accordance with the flexible tubular sub described above in its various embodiments. The tubular sub resides between the first cylindrical wellbore tool and the second cylindrical wellbore tool.
- In one embodiment the tubular sub comprises a cylindrical body having:
-
- a first end and an opposing second end, wherein each of the first and second ends defines a coupling having a first outer diameter that approximates an outer diameter of an adjoining wellbore tool;
- an elongated shaft between the first and second ends, wherein the shaft has a second outer diameter that is smaller than the first outer diameter, thereby reducing a moment of inertia for the flexible tubular sub;
- a bore extending between the first and second ends, with the bore being dimensioned to closely receive an electrical wire or data cable; and
- a transition section residing between the shaft and each of the opposing first and second ends.
- Preferably, each of the first and second wellbore tools is a perforating gun. In this instance, the tool string is a perforating gun assembly. The outer diameter of each perforating gun is formed by a respective gun barrel housing. The threads at each of the first and second ends of the tubular sub comprises female threads configured to threadedly connect to an end of a perforating gun. Optionally, the connection is made through opposing tandem subs.
- So that the manner in which the present inventions can be better understood, certain illustrations, charts and/or flow charts are appended hereto. It is to be noted, however, that the drawings illustrate only selected embodiments of the inventions and are therefore not to be considered limiting of scope, for the inventions may admit to other equally effective embodiments and applications.
-
FIG. 1 is a side, cross-sectional view of a wellbore, in one embodiment. The wellbore has been completed with an elongated horizontal section. -
FIG. 2 is a side view of an illustrative string of gun barrels forming a perforating gun assembly. The perforating gun assembly represents an illustrative rigid tool string. -
FIG. 3A is a perspective view of a flexible tubular sub of the present invention, in one embodiment. -
FIG. 3B is a cut-away view of the flexible tubular sub ofFIG. 3A . Here, an inner bore of the tubular sub is shown. -
FIG. 4 is a side view of the flexible tubular sub ofFIG. 3A . Here, the tubular sub is shown between opposing tandem subs of a perforating gun assembly. - For purposes of the present application, it will be understood that the term “hydrocarbon” refers to an organic compound that includes primarily, if not exclusively, the elements hydrogen and carbon. Hydrocarbons may also include other elements, such as, but not limited to, halogens, metallic elements, nitrogen, carbon dioxide, and/or sulfuric components such as hydrogen sulfide.
- As used herein, the terms “produced fluids,” “reservoir fluids” and “production fluids” refer to liquids and/or gases removed from a subsurface formation, including, for example, an organic-rich rock formation. Produced fluids may include both hydrocarbon fluids and non-hydrocarbon fluids. Production fluids may include, but are not limited to, oil, natural gas, pyrolyzed shale oil, synthesis gas, a pyrolysis product of coal, nitrogen, carbon dioxide, hydrogen sulfide and water.
- As used herein, the term “fluid” refers to gases, liquids, and combinations of gases and liquids, as well as to combinations of gases and solids, combinations of liquids and solids, and combinations of gases, liquids, and solids.
- As used herein, the term “subsurface” refers to geologic strata occurring below the earth's surface.
- As used herein, the term “formation” refers to any definable subsurface region regardless of size. The formation may contain one or more hydrocarbon-containing layers, one or more non-hydrocarbon containing layers, an overburden, and/or an underburden of any geologic formation. A formation can refer to a single set of related geologic strata of a specific rock type, or to a set of geologic strata of different rock types that contribute to or are encountered in, for example, without limitation, (i) the creation, generation and/or entrapment of hydrocarbons or minerals, and (ii) the execution of processes used to extract hydrocarbons or minerals from the subsurface region.
- As used herein, the term “wellbore” refers to a hole in the subsurface made by drilling or insertion of a conduit into the subsurface. A wellbore may have a substantially circular cross section, or other cross-sectional shapes. The term “well,” when referring to an opening in the formation, may be used interchangeably with the term “wellbore.”
-
FIG. 3A is a cross-sectional view of a flexibletubular sub 300 of the present invention, in one embodiment.FIG. 3B is a cross-sectional view of the flexibletubular sub 300 ofFIG. 3A . Thetubular sub 300 will be discussed with reference toFIGS. 3A and 3B together. - The
tubular sub 300 is designed to reside along an otherwise rigid string of tools, such as thegun barrel assembly 200 ofFIG. 2 . Thetubular sub 300 operates to reduce bending stress and drag on thetool string 200 while it is being pumped into or pulled out of awellbore 100. This is of particular benefit when the string of tools is being passed across the transition section, or “heel,” 153 of a horizontally completed wellbore. - The
tubular sub 300 defines a generally cylindrical body having afirst end 312 and an opposingsecond end 314. Eachend end female threads 311 for receiving male threads from an adjoining wellbore tool or connector sub. In addition, each of the first and second ends 312, 314 has a first outer diameter. - The first 312 and second 314 ends, with their
threads 311,form couplings 317. In one aspect, eachcoupling 317 extends inward from the threads about 1 to 4 inches. Flat surfaces (or “flats”) 313 may be placed around thecouplings 317 for use in torqueing thesub 300 onto an adjoining tandem sub (as shown at 225 ofFIG. 4 ). - The
tubular sub 300 also comprises anelongated shaft 316. Theshaft 316 extends between the first 312 and the second ends 314 forming a part of the cylindrical body. Of interest, theshaft 316 has a second outer diameter that is smaller than the first outer diameter. This serves to reduce a moment of inertia for the flexibletubular sub 300. It is understood that the smaller the outer diameter of theshaft 316, the better it will flex when passing across the deviated section of awellbore 100. The O.D. minimum is limited by the bending stress applied when picking up thetool string 200 from horizontal to vertical. - The
shaft 316 and opposingcouplings 317 may be fabricated from a high strength steel. Alternatively, theshaft 316 andcouplings 317 may comprise titanium, beryllium or copper. Combinations of these materials, forming an alloy, may also be used. Preferably, theshaft 316, or more specifically the material comprising theshaft 316, has a modulus of elasticity that allows theshaft 316 to deform as it is pumped across or pulled out of theheel 153 of a wellbore, and allowing theshaft 316 to return to its original shape. - The
tubular sub 300 also comprises a pair oftransition sections 318. Eachtransition section 318 resides between theshaft 316 and an opposing first 312 orsecond end 314. Eachtransition section 318 is about 1 to 4 inches in length. Preferably, theshaft 316 represents 40% to 70% inclusive of the end-to-end length of thetubular sub 300. - The
tubular sub 300 is configured to slidably receive a data cable or an electrical wire (not shown) for the transmission of signals, data or power. In this regard, the cylindrical body making up thesub 300 has abore 315 configured to receive the cable or wires. A smaller I.D. is preferred to closely hold the cable or wires. - In a preferred embodiment, the flexible
tubular sub 300 is threadedly placed between two perforating guns, such as perforatingguns 210 ofFIG. 2 . Traditional gun barrels (therigid housings 212 of the perforating guns 210) are female-by-female, with the connectingtandem subs 225 being male-by-male, meaning that each end has male threads. With this in mind, theflexible sub 300 may be used as an in-line replacement for any typical gun barrel by using the same female-by-female threaded ends. - Of course, the same ends 312, 314 of the
flexible sub 300 may be made with any combination of threads, such as male-by-female. Instead of replacing just a gun barrel, the operator may replace both a gun barrel and a sub together and then use aflexible sub 300 having male-by-female threaded ends. However, with the female-by-female design, no additional insulators, conductors, contact pins, or springs are required as the design may utilize the existing gun wire and bulkheads to pass electrical continuity through thebore 315 downhole as the replaced gun barrel would. -
FIG. 4 is a side view of the flexibletubular sub 300 ofFIG. 3A . Here, thetubular sub 300 is shown between opposingtandem subs 225 of a perforating gun assembly (such asassembly 200 ofFIG. 2 ). In this view, thetandem subs 225 are shown in greater illustrative detail, and are exploded away from thetubular sub 300, revealing male threaded ends 227. The male threaded ends 227 thread directly into respective female threaded ends 312, 314 (or couplings 317) of theflexible sub 300. - In addition to the
tandem subs 225, perforatingguns 210 are shown exploded away from opposing ends of thetubular sub 300. In this arrangement, thetubular sub 300 is connected to the perforatingguns 210 by means of thetandem subs 225. - Each
tandem sub 225 has a male threadedend 227. Onemale end 227 of atandem sub 225 connects to a female end, e.g., end 312, of thetubular sub 300, while the othermale end 227 of thetandem sub 225 connects to afemale end 217 of the perforatinggun 210. In essence, thetubular sub 300 serves as a flexible, “blank” perforating gun in a perforating gun assembly. - The
flexible sub 300 preferably has a length that is between one and five times the value of the first outer diameter In another aspect, theflexible sub 300 has an overall length that matches or approximates the length of thegun barrels 210 used in thetool string 200. For example, if there are 16-inch long gun barrels being used, theflexible sub 300 will also be 16 inches fromend 312 to end 314. Of course, the length of thetubular sub 300 may be longer or shorter than the gun barrels 210. However, the longer the length of theflexible sub 300 the more flex/deviation thesub 300 will offer, allowing the operator to navigate through more highly deviated wellbores. In one aspect, the flexibletubular sub 300 is between 2 and 12 inches in length, and more preferably between 5 and 10 inches in length. - As noted above, the
internal bore 315 of theflexible sub 300 serves as an internal chamber for holding wires and/or data cables en route to a next perforating gun downhole. The wires or data cables extend through the perforating gun assembly, transmitting detonation signals one gun at a time, from the bottom up. When a detonation signal is received from thewireline 318, the electronics inside thetandem sub 225 initiate the detonation of theupstream perforating gun 210. - In one unique embodiment, certain of the electronics are stored in the
tandem sub 225 rather than in the perforatinggun housing 212. The adjoiningtandem sub 225 holds a seal mechanism (e.g., adapter and dart or dart puck and dart) (not shown) that is designed to pressure seal the downstream end of the bore of thesub 225. In this way, detonation of the shaped charges of adownstream perforating gun 210 does not damage the electronics inside thetandem sub 225. Such seal mechanisms are provided in U.S. Ser. No. 15/808,290 entitled “Switch Sub With Two-Way Sealing Features and Method,” the entirety of which is incorporated herein by reference. - In U.S. Ser. No. 15/808,290, the term “puck” is used to mean an element having a certain surface that is used to cover an opening in a switch sub. The puck may have any shape and/or size as long as the features discussed later can be implemented in such element. The puck may be made of any appropriate material. For example, the puck may be a slab of metal. The term “dart” is used to mean an element that can partially enter inside a conduit formed in the puck. Under normal conditions, the dart can enter only partially inside the conduit. However, under increased pressure, the dart can deform and enter more inside the conduit. The dart may have any shape and/or size as long as it fulfils the features noted above. For example, the dart may be a projectile. After the shaped charged are detonated, the debris from the gun assembly, the wellbore fluid, and/or pressure wave produced by the detonation will not enter the
internal chamber 315 of the upstreamflexible sub 300 and damage the wires and/or data cables upstream. However, this arrangement is optional. - A method of running a tool string into a wellbore is also provided herein. In one aspect, the method first includes providing a wellbore. The wellbore will have a deviated section, such as a horizontal section having a heel and a toe.
- The method further comprises running a tool string into the wellbore. The tool string has a first cylindrical wellbore tool comprising a rigid housing, and a second cylindrical wellbore tool also comprising a rigid housing. Preferably, each wellbore tool is a perforating gun and the rigid housings are gun barrels.
- The tool string also includes a flexible tubular sub defining a cylindrical body. The flexible sub may be in accordance with the
sub 300 described above in its various embodiments. For example, the flexible tubular sub may comprise: -
- a cylindrical body having a first end and an opposing second end, wherein each of the first and second ends has a first outer diameter that approximates an outer diameter of an adjoining wellbore tool;
- an elongated shaft between the first and second ends, wherein the shaft has a second outer diameter that is smaller than the first outer diameter, thereby reducing a moment of inertia for the flexible tubular sub;
- a bore extending between the first and second ends, with the bore being dimensioned to closely receive an electrical wire or data cable; and
- a transition section residing between the shaft and each of the opposing first and second ends.
- The method also comprises passing the tool string through the deviated section. In one aspect, running the tool string into the wellbore and passing the tool string through the deviated section comprises pumping the tool string downhole at the end of a wireline, using hydraulic pressure.
- Preferably, each of the first and second wellbore tools is a perforating
gun 210. In this instance, the tool string is a perforating gun assembly that is run into thewellbore 100 at the end of anelectric line 240. The outer diameter of each perforating gun is formed by a respective gun barrel housing and represents the O.D. of the “adjacent wellbore tool.” - In one aspect, the threads at each of the first and second ends of the flexible tubular sub comprises female threads configured to threadedly connect to an end of a tandem sub. Each tandem sub comprises male-by-male ends, with a first male end being threadedly connected to an end of the flexible tubular sub, and a second male end being threadedly connected to an end of a perforating gun (or, more particularly, the housing of the perforating gun). Thus, the
tandem subs 225 become a means for threadedly connecting theflexible sub 300 to adjoining perforatingguns 210. In this instance, eachtandem sub 225 is threaded to a perforatinggun 210 and encases a bulkhead assembly. The bulkhead assembly includes a contact pin that transmits electrical signals fromgun barrel 210 togun barrel 210. - If a single
flexible sub 300 is run in with thetool string 200, theflexible sub 300 will ideally be placed central to thetool string 200. Alternatively, multipleflexible subs 300 may be used in thetool string 200, in which case oneflexible sub 300 would be placed at or near the top of thetool string 200 and one would be placed near the middle of thetool string 200. An additionalflexible sub 300 may be added near the bottom of the tool string. - As can be seen, a flexible joint is provided herein. The flexible joint is an improvement over known knuckle joints which can be expensive, complex and prone to failure. Further, variations of the tool and of methods for using the tool within a wellbore may fall within the spirit of the claims, below. It will be appreciated that the inventions are susceptible to other modifications, variations and changes without departing from the spirit thereof.
Claims (14)
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US16/800,395 US20200284104A1 (en) | 2019-03-05 | 2020-02-25 | Flexible Tubular Sub, and Method of Running a Tool String Into a Wellbore |
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US201962814129P | 2019-03-05 | 2019-03-05 | |
US16/800,395 US20200284104A1 (en) | 2019-03-05 | 2020-02-25 | Flexible Tubular Sub, and Method of Running a Tool String Into a Wellbore |
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USD903064S1 (en) * | 2020-03-31 | 2020-11-24 | DynaEnergetics Europe GmbH | Alignment sub |
US11339614B2 (en) | 2020-03-31 | 2022-05-24 | DynaEnergetics Europe GmbH | Alignment sub and orienting sub adapter |
US11608720B2 (en) | 2013-07-18 | 2023-03-21 | DynaEnergetics Europe GmbH | Perforating gun system with electrical connection assemblies |
USD994736S1 (en) * | 2019-04-01 | 2023-08-08 | XConnect, LLC | Tandem sub |
US11808093B2 (en) | 2018-07-17 | 2023-11-07 | DynaEnergetics Europe GmbH | Oriented perforating system |
USD1010758S1 (en) | 2019-02-11 | 2024-01-09 | DynaEnergetics Europe GmbH | Gun body |
US11906278B2 (en) | 2019-04-01 | 2024-02-20 | XConnect, LLC | Bridged bulkheads for perforating gun assembly |
USD1019709S1 (en) | 2019-02-11 | 2024-03-26 | DynaEnergetics Europe GmbH | Charge holder |
US11946728B2 (en) | 2019-12-10 | 2024-04-02 | DynaEnergetics Europe GmbH | Initiator head with circuit board |
US11988049B2 (en) | 2020-03-31 | 2024-05-21 | DynaEnergetics Europe GmbH | Alignment sub and perforating gun assembly with alignment sub |
-
2020
- 2020-02-25 US US16/800,395 patent/US20200284104A1/en not_active Abandoned
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11608720B2 (en) | 2013-07-18 | 2023-03-21 | DynaEnergetics Europe GmbH | Perforating gun system with electrical connection assemblies |
US11808093B2 (en) | 2018-07-17 | 2023-11-07 | DynaEnergetics Europe GmbH | Oriented perforating system |
USD1010758S1 (en) | 2019-02-11 | 2024-01-09 | DynaEnergetics Europe GmbH | Gun body |
USD1019709S1 (en) | 2019-02-11 | 2024-03-26 | DynaEnergetics Europe GmbH | Charge holder |
USD994736S1 (en) * | 2019-04-01 | 2023-08-08 | XConnect, LLC | Tandem sub |
US11906278B2 (en) | 2019-04-01 | 2024-02-20 | XConnect, LLC | Bridged bulkheads for perforating gun assembly |
US11946728B2 (en) | 2019-12-10 | 2024-04-02 | DynaEnergetics Europe GmbH | Initiator head with circuit board |
USD903064S1 (en) * | 2020-03-31 | 2020-11-24 | DynaEnergetics Europe GmbH | Alignment sub |
USD922541S1 (en) | 2020-03-31 | 2021-06-15 | DynaEnergetics Europe GmbH | Alignment sub |
US11339614B2 (en) | 2020-03-31 | 2022-05-24 | DynaEnergetics Europe GmbH | Alignment sub and orienting sub adapter |
US11988049B2 (en) | 2020-03-31 | 2024-05-21 | DynaEnergetics Europe GmbH | Alignment sub and perforating gun assembly with alignment sub |
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