The present disclosure relates generally to downhole coring operations and, more particularly, to an inner barrel crimping connection for a coring tool.
Conventional coring tools used to obtain core samples from a borehole include a tubular housing attached at one end to a special bit often referred to as a core bit, and at the other end to a drill string extending through the borehole to the surface. The tubular housing is usually referred to as an outer barrel or core barrel. The outer barrel contains an inner barrel or inner tube with a space between the outer surface of the inner barrel and the inner surface of the outer barrel. During a coring operation, the core bit drills into a formation and extracts a core sample of that formation. The core sample enters and fills the inner barrel, which is then subsequently returned to the surface.
For a more complete understanding of the present disclosure, its features and advantages, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
The present disclosure relates to coring tools and, in particular, to methods of using a crimp ring to couple two inner barrel sections. An end of a first inner barrel is inserted into a first end of the crimp ring and an end of a second inner barrel is inserted into a second end of the crimp ring. The first and second ends of the crimp ring are then compressed to mechanically couple the crimp ring to the ends of the first and second inner barrels. The crimp ring additionally includes a shear zone that is configured in a variety of ways such that it is easier to sever than adjacent portions of the crimp ring. For example, the shear zone may be less ductile and/or more brittle than adjacent portions of the crimp ring. The shear zone may be characterized in terms of factors that affect the relative ease by which the crimp ring severs at the shear zone. For example, the shear zone may be constructed of a relatively weak or brittle material in comparison with the material used to construct adjacent portions of the crimp ring. As another example, the shear zone may be the same material as the crimp ring, but may be thinner or heat treated locally, such as with a laser, to create an area that is more brittle or easier to sever than the adjacent portions of the crimp ring such that shear zone may be severed with less force than adjacent portions of the crimp ring. The shear zone allows for easier separation of the inner barrels and the core samples, which may be separated into approximately thirty foot sections after removal from a wellbore. For example, the crimp ring may reduce the associated time, labor, and expense involved in coupling inner barrels. Additionally, using a crimp ring may allow the inner barrels to be reused as the crimp ring is severed after a coring operation instead of the inner barrels. Further, the shear zone may reduce associated time, labor, and expense involved in separating the inner barrels. As compared to prior coring tools and methods, those of the present disclosure may be more versatile and/or easier-to-use and may also provide higher quality core samples or core sample measurements as there will be no rotation of the inner barrels during separation.
Embodiments of the present disclosure and their advantages may be better understood by referring to
The drill string 108 further includes a bottom hole assembly (BHA) 112. The BHA 112 may be assembled from a plurality of various components that operationally assist in forming the wellbore 104 including extracting core samples from the wellbore 104. For example, the BHA 112 may include drill collars, rotary steering tools, directional drilling tools, downhole drilling motors, drilling parameter sensors for weight, torque, bend and bend direction measurements of the drill string and other vibration and rotational related sensors, hole enlargers such as reamers, stabilizers, measurement while drilling (MWD) components containing wellbore survey equipment, logging while drilling (LWD) sensors for measuring formation parameters, short-hop and long haul telemetry systems used for communication, and/or any other suitable downhole equipment. The number and different types of components included in the BHA 112 may depend upon anticipated downhole drilling conditions and the type of wellbore that will be formed.
The BHA 112 may include a swivel assembly 114. The swivel assembly 114 may be an integrated component of a coring tool 102 used to isolate rotation of and torque used in rotation of a core bit 116 from other components of the coring tool 102, such as the inner barrel (as shown in
The coring tool 102 (as shown in more detail in
In operation, the core bit 116 extracts the core sample 220 from a formation such that the core sample 220 has a diameter that is approximately equal to or less than the diameter of the throat 204. The core bit 116 may be coupled to or integrated with the outer barrel 118. The outer barrel 118 is separated from inner barrels 216 by an annulus 212 that may have a generally cylindrical geometry. The outer barrel 118 may include barrel stabilizers (not expressly shown) to stabilize and provide consistent stand-off of the outer barrel 118 from a sidewall 210. Further, the outer barrel 118 may include additional components, such as sensors, receivers, transmitters, transceivers, sensors, calipers, and/or other electronic components that may be used in a downhole measurement system or other particular implementation. The outer barrel 118 may be coupled to and remain in contact with the well site 106 during operation.
Inner barrels 216-1, 216-2 and 216-3 (collectively “inner barrels 216”) pass through the outer barrel 118. The inner barrels 216 may have a generally cylindrical geometry. The inner barrels 216 may be housed in the outer barrel 118 and may be configured to slidably move uphole and downhole partially within the outer barrel 118. In some configurations, the inner barrels 216 may extend beyond the outer barrel 118.
The inner barrels 216 may house the core sample 220 extracted from the formation surrounding the wellbore 104. Following extraction from the wellbore 104, the core sample 220 is stored in the inner barrels 216 and later returned to the surface by retrieving the inner barrels 216 by wireline or by extraction of the coring assembly from the wellbore 104. Once the core sample 220 is returned to the surface, it may be severed, such as by cutting, shearing, or breaking, into multiple segments for box storage, transportation and further processing. For example, core sample may be severed to separate the core sample in the inner barrel 216-1, the core sample in the inner barrel 216-2, and the core sample in the inner barrel 216-3. As discussed in further detail below, use of the inner barrels 216 of the present disclosure may minimize damage to the core sample 220 during severing and transport.
The crimp ring 224 may couple or connect different inner barrels 216. For example, the crimp ring 224a couples the inner barrel 216-1 to the inner barrel 216-2 and the crimp ring 224b couples the inner barrel 216-2 to the inner barrel 216-3. In some examples, the crimp ring 224 may be constructed of the same or similar material as the inner barrels 216. In other examples, the crimp ring 224 may be constructed of a different material from the inner barrels 216. For example, the crimp ring 224 may be made of a multi-material including a mixture or composite of steel, plastic, or other suitable material.
The crimp ring 224 may further include a shear zone (as shown in
where:
εcrimp ring=elongation of adjacent portions of the crimp ring;
εshear zone=elongation of the shear zone; and
εratio=elongation ratio.
As another example, the shear zone may be an area that has been heat treated locally, such as with a laser, to create an area of the crimp ring 224 that is more brittle than the inner barrels 216. The crimp ring 224 allows for easier separation of the inner barrels 216 and separation of the core sample 220 into sections after removal from the wellbore 104 as the crimp ring 224 is easier to sever than the inner barrels 216. The properties of the shear zone may be created through any suitable process for increasing the brittleness of metal such as hardening by quenching, creating a heat-affected zone.
The crimp ring 324 may be installed on the inner barrels 322 before the inner barrels 322 are inserted into the outer barrel and the assembly deployed downhole. For example, at the well site, such as the well site 106 shown in
The crimp ring 324 may be preinstalled on an end of the inner barrel 322. For example, the crimp ring 324 may be preinstalled on the end 326-1 of the inner barrel 322-1 prior to deployment of the inner barrel 322-1 to the well site. The crimp ring 324 may be coupled to the end 326-1 via any suitable coupling, such as welding, crimping, or threading. When the inner barrel 322-1 arrives at the well site, the end 326-2 of the inner barrel 322-2 may be inserted into the crimp ring 324 and the crimp ring 324 may be compressed to couple the crimp ring 324 to the inner barrel 322-2 and thus couple the inner barrel 322-1 to the inner barrel 322-2. Preinstallation of the crimp ring 324 on one inner barrel 322 may reduce the assembly time of the coring system at the well site.
In some examples, the crimp ring 324 may be located over one or more protrusions 330. The protrusions 330 may be formed on the outer perimeter of the inner barrels 322 to increase the physical interference between the crimp ring 324 and the inner barrel 322 after the crimp ring 324 has been crimped. The increased physical interference increases the mechanical contact friction between the crimp ring 324 and the inner barrel 322 and increases the pulling force required to separate the crimp ring 324 from the inner barrel 322 when an axial force is applied to the system 300. In some examples, the protrusion 330 may have a positive shape and extend above the surface of the outer perimeter of the inner barrel 322. The protrusion 330-1 is an example of a positive shape. In other examples, the protrusion 330 may have a negative shape and extend below the surface of the outer perimeter of the inner barrel 322. The protrusion 330-2 is an example of a negative shape. The cross-sectional shape of the protrusion 330 may be any suitable geometry including circular, oval, square, rectangular, or trapezoidal. For example, in
The protrusion 330 may additionally provide a visual indicator during installation of the crimp ring 324. For example, an installer of the crimp ring 324 may visually determine that the crimp ring 324 is properly placed when the crimp ring 324 is situated over the protrusions 330. When the crimp ring 324 is in place over the end 326 of the inner barrel 322, a crimping tool may be used to compress the crimp ring 324 to couple the inner barrels 322.
The crimp ring 324 may additionally include one or more shoulders 332 on the inner perimeter of the crimp ring 324 near one or both axial ends of the crimp ring 324. The shoulders 332 may be placed at a distance from the axial end of the crimp ring 324 such that the crimp ring 324 overlaps the ends 326 of the inner barrels 322 by an amount that provides sufficient mechanical contact friction between the inner perimeter of the crimp ring 324 and the outer perimeter of the inner barrel 322. For example, the crimp ring 324 may overlap the ends 326 by a distance between approximately one and five times the diameter of the inner barrel 322. The shoulders 332 may be used to prevent the ends 326-1 and 326-2 of the inner barrels 322 from contacting each other after the inner barrels 322-1 and 322-2 are coupled together, leaving a gap 328 between the ends 326-1 and 326-2. The gap 328 may reduce the time used to sever and separate the inner barrels 332-1 and 332-2 after the coring operation as the cutting tool severs the crimp ring 324 and does not damage the inner barrels 322. Leaving the inner barrels 322 intact may allow the inner barrels 322 to be reused in another coring operation.
The crimp ring 324 may further include a shear zone 334 extending longitudinally for at least a portion of the crimp ring 324. The shear zone 334 may be of any suitable length and may be configured to enable severing of the crimp ring 324 using a fast pipe cutter or other cutting tool. The shear zone 334 may be formed of the same or similar material as the adjacent portions of the crimp ring 324 but may be thinner than other portions of the crimp ring 324 such that the shear zone 334 may be easier to sever after the coring operation. In some examples, the shear zone 334 may be an area that has been heat treated locally, such as with a laser, to create an area that is more brittle or easier to sever than other areas of the crimp ring 324 such that the shear zone 334 may be severed with less force than other areas of the crimp ring 324. A more brittle shear zone 334 allows for easier severing of the crimp ring 324 and separation of the core sample 320 into sections after removal from the wellbore, such as the wellbore 104 shown in
The crimp ring 324 may additionally include one or more sealing members 336 on the inner perimeter of the crimp ring 324. The sealing members 336 may provide a secondary seal where the crimp ring 324 couples to the inner barrels 322. The sealing members 336 may be any suitable seal type including an O-ring, a V-ring, or a lip seal. The sealing member 336 may be made of any suitable elastomeric material. The elastomeric material may be formed of compounds including, but not limited to, natural rubber, nitrile rubber, hydrogenated nitrile, urethane, polyurethane, fluorocarbon, perflurocarbon, propylene, neoprene, hydrin, etc, or a soft material including, but not limited to, bronze and brass.
The crimp ring 324 may further include a gripping ring 338 located along the inner perimeter of the crimp ring 324. The gripping ring 338 may be a one-way clamp such that the inner barrel 322-2 may be pushed into the crimp ring 324, but may not be pulled out of the crimp ring 324. The gripping ring 338 may provide for easier installation and coupling of the crimp ring 324 and the inner barrels 322.
The crimp rings 324 may be used to couple multiple sections of the inner barrels 322 together. For example, at the well site 106 as shown in
In some examples, after the coring operation, the crimp ring 324 may be severed using the same crimping tool used to compress crimp ring 324 during the installation process. For example, some crimping tools have removable jaws such that a crimping jaw may be used during installation and a cutting jaw may be used to sever the crimp ring 324.
The operator may position the crimp ring over one or more protrusions formed on the first inner barrel. The protrusions may increase the mechanical contact friction between the inner perimeter of the crimp ring and the outer perimeter of the inner barrel such that a larger pulling force is required to separate the crimp ring and the inner barrel after the crimp ring has been compressed. The protrusions may additionally provide a visual indicator to allow an installer to determine when the crimp ring is properly aligned on the end of the first inner barrel. The protrusions may have any suitable positive or negative shape and any suitable geometry.
In some examples, the operator may couple the crimp ring to the first inner barrel at the well site prior to a coring operation. In other examples, the operator may preinstall the crimp ring on an end of the first inner barrel prior to deployment of the first inner barrel to the well site. The crimp ring may be preinstalled on the first inner barrel via any suitable coupling, including crimping, welding, or threading. Preinstallation of the crimp ring on the first inner barrel may reduce the assembly time of the coring system at the well site.
At step 404, the operator may insert a first end of a second inner barrel into a second end of the crimp ring. For example, with reference to
At step 406, the operator may compress the crimp ring to couple the crimp ring to the first inner barrel. For example, with reference to
At step 408, the operator may compress the crimp ring to couple the crimp ring to the second inner barrel. For example, with reference to
At step 410, the operator may determine whether there are additional inner barrel sections to couple together. If there are additional inner barrels to couple, the method 400 may return to step 402 to install the next crimp ring to couple the next inner barrel. If there are no additional inner barrels to couple, the method 400 may proceed to step 412.
At step 412, the operator may use the coupled inner barrels during a coring operation. During the coring operation, the operator lowers the inner barrel assembly into an outer barrel located downhole in a wellbore, uses the inner barrel assembly to collect a core sample, and returns the inner barrel assembly to the surface to obtain the core sample. For example, with reference to
After the coring operation, at step 414, the operator may separate the inner barrel sections by severing the crimp ring such that no damaging of the inner barrels may be necessary. Because the inner barrels are not damaged, the potential for disturbing the core sample is reduced. The rig time and associated expense necessary for severing the inner barrels is also mitigated. Additionally, the inner barrel sections may be reused.
The crimp ring may be severed in a shear zone that may be formed of a material that is more brittle or easier to sever than the adjacent portions of the crimp ring such that the shear zone may be severed with less force than the adjacent portions of the crimp ring. The shear zone may be made of a different material than the adjacent portions of the crimp ring, may be thinner than the adjacent portions of the crimp ring, or may be heat-treated to increase the brittleness in the shear zone.
The operator may separate the inner barrels using the crimping tool used to compress the crimp ring in steps 406 and 408 by replacing the crimping jaws on the crimping tool with cutting jaws. The cutting jaws may sever the crimp ring, and depending on the parameters of the coring operation, also sever the core sample.
The steps of the method 400 may be completed in any order and some steps may be omitted or performed simultaneously with other steps. For example, steps 406 and 408 may be completed simultaneously.
Embodiments disclosed herein include:
A. An inner barrel system including a first coring inner barrel; a second coring inner barrel; and a crimp ring overlapping an end of the first coring inner barrel and an end of the second coring inner barrel and compressed to mechanically couple the first coring inner barrel with the second coring inner barrel.
B. A method for coupling coring inner barrel sections including inserting an end of a first coring inner barrel into a first end of a crimp ring; inserting an end of a second coring inner barrel into a second end of the crimp ring; and compressing the first and second ends of the crimp ring to mechanically couple the crimp ring to the end of the first coring inner barrel and the end of the second coring inner barrel.
C. A coring system including a core bit; a coring outer barrel coupled to the core bit; a coring inner barrel assembly inserted into the coring outer barrel. The coring inner barrel assembly including a first coring inner barrel; a second coring inner barrel; and a crimp ring overlapping an end of the first coring inner barrel and an end of the second coring inner barrel and compressed to mechanically couple the first coring inner barrel with the second coring inner barrel.
Each of embodiments A, B, and C may have one or more of the following additional elements in any combination: Element 1: wherein at least one of the first coring inner barrel or the second coring inner barrel includes a protrusion on an outer perimeter of at least one of the first coring inner barrel or the second coring inner barrel. Element 2: wherein the protrusion has at least one of a positive shape or a negative shape. Element 3: wherein a cross-sectional shape of the protrusion is at least one of a circle, oval, square, rectangle, and trapezoid. Element 4: wherein the crimp ring includes a shoulder extending from an inner perimeter of the crimp ring. Element 5: wherein the crimp ring includes a shear zone extending longitudinally along at least a portion of the crimp ring. Element 6: wherein the shear zone is an area that is more brittle than an adjacent portion of the crimp ring such that the shear zone severs with less force than the adjacent portion of the crimp ring. Element 7: wherein a thickness of the shear zone is less than a thickness of another portion of the crimp ring. Element 8: wherein the shear zone is scored. Element 9: further comprising positioning the crimp ring over at least one protrusion on an outer perimeter of at least one of the first coring inner barrel or the second coring inner barrel. Element 10: wherein inserting the end of at least one of the first coring inner barrel or second coring inner barrel includes inserting the end until the end contacts a shoulder extending from an inner perimeter of the crimp ring. Element 11: further comprising creating a shear zone extending longitudinally along at least a portion of the crimp ring. Element 12: wherein creating the shear zone includes locally heat treating the shear zone. Element 13: further comprising: performing a coring operation; and severing the crimp ring to separate the first and second inner barrels.
Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alternations can be made herein without departing from the spirit and scope of the disclosure as defined by the following claims. For example, the crimp ring may additionally include features such as a small pressure release valve to release downhole pressure when the core sample is returned to the surface.
Filing Document | Filing Date | Country | Kind |
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PCT/US2016/020591 | 3/3/2016 | WO | 00 |