Patent Publication Number: US-10767431-B2

Title: Inner barrel crimping connection for a coring tool

Description:
RELATED APPLICATIONS 
     This application is a U.S. National Stage Application of International Application No. PCT/US2016/020591 filed Mar. 3, 2016, which designates the United States, and which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates generally to downhole coring operations and, more particularly, to an inner barrel crimping connection for a coring tool. 
     BACKGROUND 
     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. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       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: 
         FIG. 1  is an elevation view, with portions broken away, of a drilling system; 
         FIG. 2  is a cross-sectional view of the coring tool of  FIG. 1  used to extract a core sample from a wellbore; 
         FIGS. 3A-3I  is an exemplary inner barrel system used to couple two sections of an inner barrel with a crimp ring; and 
         FIG. 4  is a flow chart for a method of coupling inner barrels using a crimp ring. 
     
    
    
     DETAILED DESCRIPTION 
     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  FIGS. 1-4 , where like numbers are used to indicate like and corresponding parts. 
       FIG. 1  is an elevation view, with portions broken away, of a drilling system  100  at a well site  106 . A drilling rig (not expressly shown) may be included at the well site  106  to support and operate a drill string  108  at the well site  106  for drilling a wellbore  104 . Such a drilling rig may be used to suspend the drill string  108  over the wellbore  104  as the wellbore  104  is drilled, and may include various types of drilling equipment such as a rotary table, drilling fluid pumps, and drilling fluid tanks used in drilling. Such a drilling rig may have various characteristics and features associated with a “land drilling rig,” such as a rig floor. However, the present teachings are not limited to use with a land drilling rig and may be equally used with offshore platforms, drill ships, semi-submersibles, and drilling barges. 
     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  FIG. 2 ). 
     The coring tool  102  (as shown in more detail in  FIG. 2 ) is coupled to the drill string  108 . The coring tool  102  and the drill string  108  extend down from the well site  106 . The coring tool  102  includes a core bit  116 , which may have a central opening and may include one or more blades disposed outwardly from exterior portions of a bit body of the core bit  116 . The bit body may be generally curved and the one or more blades may be any suitable type of projections extending outwardly from the bit body. The blades may include one or more cutting elements disposed outwardly from exterior portions of each blade. The core bit  116  may be any of various types of fixed cutter core bits, including polycrystalline diamond cutter (PDC) core bits, including thermally stable polycrystalline diamond cutter (TSP) core bits, matrix core bits, steel body core bits, hybrid core bits, and impreg core bits operable to extract a core sample from the wellbore  104 . The core bit  116  may have many different designs, configurations, or dimensions according to the particular application of the core bit  116 . The coring tool  102  further includes an outer barrel  118  and an inner barrel (discussed in detail with reference to  FIG. 2 ) located inside the outer barrel  118 . 
       FIG. 2  is a cross-sectional view of the coring tool  102 , as shown in  FIG. 1 , used to extract and store, after extraction, a core sample  220  from the wellbore  104 . The coring tool  102  includes the core bit  116  having a generally cylindrical body and including a throat  204  that extends longitudinally through the core bit  116 . The throat  204  of the core bit  116  may receive the core sample  220 . The core bit  116  includes one or more cutting elements  206  disposed outwardly from exterior portions of a core bit body  208 . For example, a portion of each cutting element  206  may be directly or indirectly coupled to an exterior portion of the core bit body  208 . Cutting elements  206  may be any suitable device configured to cut into a formation, including but not limited to, primary cutting elements, back-up cutting elements, secondary cutting elements or any combination thereof. By way of example and not limitation, cutting elements  206  may be various types of cutting elements, compacts, buttons, inserts, and gage cutting elements satisfactory for use with a wide variety of core bits  116 . 
     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  224   a  couples the inner barrel  216 - 1  to the inner barrel  216 - 2  and the crimp ring  224   b  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  FIG. 3A ) extending longitudinally for at least a portion of the crimp ring  224 . The shear zone may be of any suitable length and may be configured to enable severing of the crimp ring  224  using a fast pipe cutter or other cutting tool. The shear zone may be formed of the same or similar material as the adjacent portions of the crimp ring  224  but may be thinner than adjacent portions of the crimp ring  224  such that the shear zone may be easier to sever after the coring operation. In other examples, the shear zone may be made of a different material that the adjacent portions of the crimp ring  224  or may be treated such that the shear zone is more brittle, easier to sever, or has a lower ductility. For example, the shear zone of the crimp ring  224  may be constructed of a material that maintains yield strength and tensile strength approximately equivalent to the yield strength and tensile strength of the inner barrels  216  including cast iron, aluminum smelting, or other material with that becomes more brittle with heat treatment. Additionally, by way of example and not limitation, the shear zone of the crimp ring  224  may have a ductility according to the following elongation ratio: 
     where: 
     
       
         
           
             
               
                 
                   
                     
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     ε crimp ring =elongation of adjacent portions of the crimp ring; 
     ε shear zone =elongation of the shear zone; and 
     ε ratio =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. 
       FIG. 3A  is an exemplary inner barrel system used to couple two sections of an inner barrel with a crimp ring. The inner barrel system  300  includes inner barrels  322 - 1  and  322 - 2  coupled by a crimp ring  324 . The inner barrels  322  may be configured to connect or couple to other inner barrels  322  using additional crimp rings  324 . The crimp ring  324  may be made of any suitable ductile material that withstands the conditions in the wellbore and has a high yield strength and high elongation, such as aluminum, steel, stainless steel, or copper. For example, the crimp ring  324  may be made of a stainless steel, such as AISI  316  stainless steel. 
     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  FIG. 1 , the crimp ring  324  may be placed over the gap  328  between the end  326 - 1  of the inner barrel  322 - 1  and the end  326 - 2  of the inner barrel  322 - 1 . The crimp ring  324  may be installed on the outer perimeter of the inner barrel  322  by inserting an end of the inner barrel  322  into an end of the crimp ring  324  until the inner barrel  322  is inserted a predetermined distance. After the inner barrel  216  is inserted into an end of the crimp ring  324 , the crimp ring  324  may be compressed and plastically deformed—generally referred to as crimping—to fit snugly against the outer perimeter of the inner barrels  322  such that the crimp ring  324  couples to the inner barrel  322 - 1 . This process may be repeated to couple the crimp ring  324  with a second inner barrel  322  such that two inner barrels  322  are coupled together. The crimp ring  324  may be crimped by any suitable means of deforming metal, such as through the use of a piston-pressure device or a crimping tool. 
     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  FIG. 3A , the protrusion  330 - 1  has a positive trapezoidal shape and the protrusion  330 - 2  has a negative trapezoidal shape. For further examples,  FIG. 3B  illustrates the protrusion  330 - 1  with a positive circular shape,  FIG. 3C  illustrates the protrusion  330 - 1  with a positive oval shape,  FIG. 3D  illustrates the protrusion  330 - 1  with a positive square cross-sectional shape,  FIG. 3E  illustrates the protrusion  330 - 1  with a positive rectangular shape,  FIG. 3F  illustrates the protrusion  330 - 1  with a negative circular shape,  FIG. 3G  illustrates the protrusion  330 - 1  with a negative oval shape,  FIG. 3H  illustrates the protrusion  330 - 1  with a negative square cross-sectional shape, and  FIG. 3I  illustrates the protrusion  330 - 1  with a negative rectangular shape. While the inner barrels  322  are illustrated in  FIG. 3A  as each having one protrusion  330 , the inner barrels  322  may have any number of protrusion, any combination of geometry, and any combination of positive and negative shapes. 
     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  FIG. 1 . Additionally, the shear zone  334  may be scored to allow for easier severing of the crimp ring  324  after removal from the wellbore. 
     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  FIG. 1 , the crimp rings  324  may be used to couple a series of inner barrels  322  together. During coring operations, the core sample  320  may be captured and housed in the inner barrels  322 , which may be returned to the surface. After the inner barrels  322  return to the surface with an extracted core sample  320 , the shear zones  334  allow for efficient severing and separation of each inner barrel. The core sample  320  may be severed to separate the core sample  320  in the different inner barrels  322 . 
     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 . 
       FIG. 4  is a flow chart of a method of coupling inner barrels using a crimp ring. A method  400  beings at step  402 , where an operator inserts a first end of a first inner barrel into a first end of a crimp ring. For example, with reference to  FIG. 3A , the operator may align the crimp ring  324  with the end  326 - 1  of the inner barrel  322 - 1 . The crimp ring may be made of any suitable ductile material that withstands the conditions in the wellbore and has a high yield strength and high elongation, such as aluminum, steel, stainless steel, or copper. The operator may align the crimp ring on the outer perimeter of the first inner barrel by sliding the inner barrel into the crimp ring until the inner barrel is inserted by a predetermined distance. For example, the operator may insert the inner barrel into the crimp ring until the inner barrel contacts a shoulder located on the inner perimeter of the crimp ring. 
     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  FIG. 3A , the operator may insert the end  326 - 2  of the inner barrel  322 - 2  into the crimp ring  324 . The operator may position the crimp ring on the end of the second inner barrel in a manner similar to the manner described in step  402 . 
     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  FIG. 3A , the operator may compress the portion of the crimp ring  324  surrounding the end  326 - 1  to couple the crimp ring  324  to the inner barrel  322 - 1 . The compression may plastically deform the crimp ring such that the crimp ring fits snugly against the outer perimeter of the first inner barrel. The crimp ring and the inner barrel may be coupled using mechanical contact friction. The operator may compress crimp ring using any suitable tool for deforming metal including a piston pressure device or a crimping tool. 
     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  FIG. 3A , the operator may compress the portion of the crimp ring  324  surrounding the end  326 - 2  to couple the crimp ring  324  to the inner barrel  322 - 2 . The operator may compress crimp ring to couple the crimp ring with the second inner barrel in a manner similar to the manner described in step  408 . 
     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  FIG. 2 , the inner barrels  216  are coupled to each other using the crimp rings  224  to create the inner barrel assembly. The inner barrels  216  are lowered into the outer barrel  118  and used to collect the core sample  220 . Once the core sample  220  is in the inner barrels  216 , the inner barrels  216  are returned to the surface  106  in order to obtain the core sample. 
     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.