Patent Description:
Formation coring is a well-known process in the oil and gas industry. In conventional coring operations, a core barrel assembly is used to cut a cylindrical core from the subterranean formation and to transport the core to the surface for analysis. Analysis of the core can reveal valuable data concerning subsurface geological formations-including parameters such as permeability, porosity, and fluid saturation-that are useful in the exploration for and production of petroleum, natural gas, and minerals. Such data may also be useful for construction site evaluation and in quarrying operations.

As shown in <FIG>, a conventional core barrel assembly <NUM> may include an outer barrel <NUM> having, at a bottom end, a core bit <NUM> adapted to cut the cylindrical core and to receive the core in a central opening, or throat <NUM>. The opposing end of the outer barrel is attached to the end of a drill string, which conventionally comprises a plurality of tubular sections that extends to the surface. Located within, and releasably attached to, the outer barrel is an inner barrel assembly having an inner tube configured to receive the core as the core traverses the throat of the core bit and to retain the core for subsequent transportation to the surface.

One conventional approach to preserving the integrity of the core and obtaining reliable formation data, especially reservoir fluid properties such as oil and water saturation, is coring with a fluid retaining functionality, for example, sponge coring. Sponge coring is performed using a "sponge core barrel. " Generally, a sponge core barrel comprises a conventional core barrel assembly, as described above, that has been adapted for use with one or more sponge liners <NUM>. Each sponge liner includes a layer of material selected for its ability to absorb or adsorb the reservoir fluid of interest (for example, oil) from a core sample. Similar to the sponge material approach, there are other ways to construct a material to absorb or adsorb formation fluids of interest. In the context of the present disclosure, the term "sponge" refers to any material that is suitable to absorb or adsorb fluids escaping the formation sample material. As non-limiting examples, this could be material with a porous foam like structure, a felt like structure, a fur like structure, a fabric structure or woven structures, in individual or a multitude of layers, or any combination of the foregoing structures. Also, the terms "absorb" and "adsorb" are used synonymously in this application to describe the capability of keeping formation fluids in a certain location immobilized to a certain degree, even though the technical meanings of these terms are different.

As shown in <FIG>, a conventional sponge liner comprises an annular sponge layer <NUM> encased in a tubular sleeve <NUM>. The annular sponge layer <NUM> is constructed of a material adapted to absorb a specified reservoir fluid of interest. For example, if the particular formation characteristic of interest is oil saturation, the sponge layer <NUM> may be constructed of an oil-absorptive material such as, by way of non-limiting example, a polyurethane foam. To obtain formation water saturation data, a water-absorptive material is used to construct the sponge layer <NUM>. The tubular sleeve <NUM> provides structural support for the annular sponge layer <NUM> and is typically constructed of a relatively rigid material such as, as a non-limiting example, metal. The annular sponge layer <NUM> is adhered to an interior cylindrical surface <NUM> of the sleeve <NUM>. Because the sponge layer <NUM> contacts the core and is relatively flexible as compared to the core, the sponge liners serve to contain the core and protect the core from mechanical damage. Sponge liners are typically supplied in sections, a number of which are placed end-to-end within the inner tube to substantially fill the length (usually a standard <NUM> feet, although shorter or longer lengths are possible) of the inner tube. The tubular sleeve <NUM> of a conventional sponge liner typically comprises an aluminum material.

The inner barrel assembly of a sponge core barrel includes an inner tube adapted to receive the plurality of sponge liners <NUM>. During a coring operation, a core shoe disposed at the lower end of the inner tube guides a core <NUM> being cut into the inner tube and sponge liners <NUM> disposed therein, where the core is retained for subsequent transportation to the surface and later analysis. A substantially cylindrical interior cavity <NUM> of the annular sponge layer is of a diameter substantially equal to the diameter of the core being cut, such that an interior cylindrical surface <NUM> of the annular sponge layer substantially continuously contacts the exterior surface <NUM> of the core <NUM> or is in immediate proximity to it, so that any fluid of interest exiting the core <NUM> will be absorbed by the sponge layer <NUM> and will not flow off and disperse into the drilling fluid system of the core barrel assembly. The substantially continuous contact between the annular sponge layer <NUM> and the core <NUM> often results in the application of significant sliding frictional forces F on the core <NUM> as the core <NUM> moves through the core barrel, which frictional forces can, in some instances, overcome the compressive strength of the formation material, causing the core <NUM> to compact, fracture, jam, or otherwise become damaged. The significant frictional forces between the core <NUM> and annular sponge layer <NUM> can also exceed the available weight-on-bit (WOB) applicable to the drill string to which the core barrel assembly is secured, causing the rate-of-penetration (ROP) of the core bit to drop significantly.

When the inner barrel assembly and core <NUM> are raised to the surface, where the ambient pressure may be significantly less than the downhole pressure, formation gases within the core sample may expand and expel reservoir fluids from the core <NUM>. The expelled reservoir fluids are then absorbed by the annular sponge layer <NUM> and preserved for later analysis, rather than separating from the core sample and flowing out, as by gravity, from the inner tube. Perforations in the sleeve <NUM> of the sponge liner allow reservoir gases to escape.

<CIT> discloses a core barrel. <CIT> discloses core drilling apparatus.

<CIT> discloses a container for receiving a sample. <CIT> discloses a lifter for a rotary core drill.

This summary is provided to introduce a selection of concepts in a simplified form. These concepts are described in further detail in the detailed description of embodiments of the disclosure below.

According to one aspect the present invention provides a liner tube for a core barrel assembly as claimed in claim <NUM>.

In additional embodiments, the sleeve has at least two circumferential segments each having an inner surface coupled to the layer of material. The layer of material is configured to absorb or adsorb formation fluids or portions thereof. The at least two circumferential segment of the sleeve may be separated from one another by slots formed through a wall of the sleeve. The liner may include an elastic element in contact with the at least two circumferential segments of the sleeve, the elastic element extending in a circumferential direction.

In yet additional embodiments, the liner includes at least one elastic element located on an outer surface of the at least two separate liner segments, the at last one elastic element configured to act as a spring member.

According to another aspect the present invention provides a method of building a coring tool as claimed in claim <NUM>.

The present invention also provides a method of coring a formation of subterranean earth material including engaging a formation of subterranean earth material with the coring tool. The method may include modifying the circumferential flexibility of the at least one liner prior to a coring operation or during the course of a coring operation. Modifying the flexibility of the at least one liner comprises one or more of: adding or removing one or more spring members extending at least partially about a circumference of the sleeve; and breaking one or more formations of material of a wall of the sleeve between adjacent slots formed in the wall of the sleeve.

In embodiments, the method of coring a formation of subterranean earth material includes expanding the sleeve radially as a core sample extends within the liner.

In other embodiments the at least one slot is configured to provide the sleeve with a predetermined degree of elasticity in a radial direction from a longitudinal axis of the sleeve.

In other embodiments, the method of building the coring tool includes affixing the annular layer of sponge material to an inner surface of the sleeve.

The illustrations presented herein are not meant to be actual views of any sponge core barrel, sponge liner, sleeve, or component thereof, but are merely idealized representations that are used to describe embodiments of the disclosure.

As used herein, directional terms, such as "above"; "below"; "up"; "down"; "upward"; "downward"; "top"; "bottom"; "top-most"; "bottom-most"; "proximal" and "distal" are to be interpreted from a reference point of the object so described as such object is located in a vertical well bore, regardless of the actual orientation of the object so described. For example, the terms "above"; "up"; "upward"; "top"; "top-most" and "proximal" are synonymous with the term "uphole," as such term is understood in the art of subterranean well bore drilling. Similarly, the terms "below"; "down"; "downward"; "bottom"; "bottom-most" and "distal" are synonymous with the term "downhole," as such term is understood in the art of subterranean well bore drilling and coring operations.

As used herein, the term "longitudinal" refers to a direction parallel to a longitudinal axis of the sponge liner. For example, a "longitudinal" cross-section shall mean a "cross-section viewed in a plane extending along the longitudinal axis of the sponge liner.

As used herein, the terms "lateral"; "laterally"; "transverse" or "transversely" shall mean "transverse to a longitudinal axis of the sponge liner. " For example, a "lateral" or "transverse" cross-section shall mean a "cross-section viewed in a plane transverse to the longitudinal axis of the sponge liner.

<FIG> illustrates a tubular sleeve <NUM>, or "sponge liner tube" or "shell," of a sponge liner according to an embodiment of the present disclosure. The tubular sleeve may comprise aluminum or one or more other materials, such as other metals, alloys, or a polymer composite. The tubular sleeve <NUM> may be of substantially cylindrical shape. Additionally, as shown in <FIG>, the tubular sleeve <NUM> may have internal ribs or protrusions <NUM>, directed either substantially parallel to or slanted or spiraling with respect to the longitudinal axis L of the sleeve <NUM>. In some embodiments, stub-like protrusions <NUM> may be located on an interior of the sleeve <NUM>. The tubular sleeve <NUM> may include a plurality of slots <NUM> extending radially through a wall <NUM> of the tubular sleeve <NUM> from an outer surface <NUM> of the sleeve <NUM> to an inner surface <NUM> of the sleeve <NUM>. The slots <NUM> provide the tubular sleeve <NUM> with increased elasticity in a circumferential direction with respect to a longitudinal axis of the sleeve <NUM>, allowing an annular sponge layer attached to the inner surface <NUM> of the sleeve <NUM> (shown in <FIG> and <FIG>) to maintain contact with a core entering the sleeve <NUM> while reducing frictional forces between the sponge layer and the core as the core enters the sponge liner. The sponge layer may include any absorptive material known in the art. By way of non-limiting example, the sponge layer may include a polyurethane foam, a felt, a fur, a fabric, a woven structure, or any combination of the foregoing. The slots <NUM> may be evenly spaced apart about a circumference of the sleeve <NUM>. For example, as shown in <FIG>, the sleeve <NUM> may include four (<NUM>) slots <NUM>, each of which may be spaced apart from the nearest slot <NUM> by about <NUM> degrees about the circumference of the sleeve <NUM>. However, in other embodiments, the slots <NUM> may be unevenly spaced apart about the circumference of the sleeve <NUM>.

The slots <NUM> may be formed by a wide variety of processes, including, by way of non-limiting example, cutting, milling, or other methods. Alternatively, the sleeve <NUM> may be formed to include the slots <NUM> from the outset by a casting process, such as centrifugal casting, or other methods.

Moreover, while four (<NUM>) slots <NUM> are shown extending through the wall <NUM> of the tubular sleeve <NUM> of <FIG>, it is to be appreciated that fewer or more than four (<NUM>) slots may be formed in the wall <NUM> of the sleeve <NUM>. For example, the sleeve <NUM> may include as few as one (<NUM>) slot <NUM> formed through the wall <NUM> thereof. In other embodiments, the sleeve <NUM> may include six (<NUM>) slots <NUM> formed through the wall <NUM> thereof. In such an embodiment, the six (<NUM>) slots may be spaced apart at about <NUM> degree intervals about a circumference of the sleeve <NUM>. However, as previously described, the six (<NUM>) slots may be spaced apart at uneven intervals about a circumference of the sleeve. In further embodiments, the sleeve <NUM> may include eight (<NUM>) or more slots <NUM> formed through the wall <NUM> thereof. The present disclosure does not contemplate an upper limit to the amount of slots <NUM> formed through the wall <NUM> of the tubular sleeve <NUM>.

Additionally, while the slots <NUM> are shown as extending longitudinally along the sleeve <NUM>, in some embodiments the slots <NUM> may also include portions oriented and extending substantially radially along the circumference of the sleeve <NUM>. In further embodiments, the slots <NUM> may have longitudinally extending portions or segments, radially extending portions or segments, obliquely extending portions or segments, or irregularly oriented portions or segments. It is to be understood that any pattern or orientation of the slots <NUM> is within the scope of the present disclosure.

Each of the slots <NUM> may include a plurality of slot segments <NUM> separated by distinct formations of material, or "tabs" <NUM>, of the material of the sleeve <NUM>. For example, slot 102a of <FIG> includes three (<NUM>) slot segments 110a, 110b, 110c separated by two (<NUM>) tabs 112a, 112b. A longitudinally uppermost end of slot 102a may be separated from an upper end <NUM> of the sleeve <NUM> by a tab 112c, while a longitudinally bottom end of slot 102a may be separated from a bottom end <NUM> of the sleeve <NUM> by a tab 112d. <FIG> illustrates a magnified view of a tab <NUM> separating two segments of a slot <NUM>. It is to be appreciated that the tab <NUM> may be configured as any portion of the sleeve wall <NUM> located between one segment of a slot <NUM> and an adjacent segment of the same or a different slot <NUM> or between a segment of the slot <NUM> and an adjacent upper end <NUM> or lower end <NUM> of the sleeve <NUM>. The tabs <NUM> may have various shapes and configurations, and are not limited to the design illustrated in <FIG>, as will be discussed in more detail below. The combination of the slots <NUM> and the tabs <NUM> enables the sleeve <NUM> to exhibit a higher elasticity, particularly in the circumferential direction (which also provides a higher degree of elasticity in the radial direction), while also maintaining the sleeve <NUM> as a single, integral body. The slots <NUM> and tabs <NUM> may optionally be located and oriented such that, at each longitudinal location of the sleeve <NUM>, the sleeve wall <NUM> does not extend continuously about the entire circumference of the sleeve <NUM>.

With continued reference to <FIG>, if greater flexibility of the sleeve <NUM> is required, one or more of the tabs <NUM> interposed between segments of a slot <NUM> may be fractured to join segments of the slot <NUM>. Slot 102b of <FIG> is shown having each of the tabs <NUM> of the wall <NUM> fractured or otherwise removed, allowing the slot 102b to extend continuously from the upper end <NUM> of the sleeve <NUM> to the lower end <NUM> of the sleeve <NUM>, thus increasing the radial flexibility of the sleeve <NUM> and, correspondingly, the radial flexibility of a sponge layer attached to the inner surface of the sleeve <NUM>. For illustrative purposes, <FIG> shows slot 102a with all the tabs <NUM> in place and slot 102b with all of the tabs <NUM> removed or fractured, it is to be understood that this is for illustrative purposes. In practice, a user may fracture or remove selected tabs <NUM> from any of the slots <NUM> in any desired pattern to provide the sleeve <NUM> with a desired degree of radial elasticity. For example, a user may fracture or remove the tabs <NUM> of the slots <NUM> in a manner to provide the sleeve <NUM> with a uniform degree of increased elasticity in the radial direction. <FIG> shows a magnified view of a slot <NUM> with a tab removed between adjacent slot segments. The tabs <NUM> may be removed by fracturing or other methods. The tabs <NUM> may be fractured or removed at the drilling site or prior to transfer to the drill site, or the sleeve could be manufactured with a reduced number of tabs in the beginning. The ability to fracture or remove the tabs <NUM>, or to choose from a variety of sleeves with manufactured with different mount of tabs, allows a user to adjust the elasticity of the tubular sleeve <NUM>, and thus the associated sponge liner, to tailor the elasticity of the sponge liner to a particular formation to be cored. For example, prior to coring a formation, a user may remove as many of the tabs as necessary to provide the sleeve <NUM> with a desired degree of enhanced elasticity in consideration of the parameters of a formation to be cored. To achieve a maximum elasticity of a particular sponge liner of the present disclosure, a user may remove or fracture all of the tabs associated with each of the slots <NUM>. In this manner, as a core <NUM> moves upward within the sponge liner as the coring tool progresses downward into the formation, an annular sponge layer attached to the inner surface <NUM> of the sleeve <NUM> may remain in contact with the core <NUM> while also exerting a decreased amount of friction on the core <NUM> by virtue of the elasticity of the sleeve <NUM> provided by the arrangement of the slots <NUM> and tabs <NUM> therein. Moreover, the increased elasticity of the sleeve <NUM>, configured as disclosed herein, allows one or both of the sleeve and the sponge layer to have an inner diameter smaller than that of a sponge layer of a prior art sponge liner without a corresponding increased risk of damage to the core <NUM> caused as a result of friction between the core <NUM> and the sponge layer. It is to be appreciated that the elasticity of the sleeve <NUM> may also be increased by forming the sleeve <NUM> to have a fewer number of tabs <NUM> interposed between slot segments.

The slots <NUM> and tabs <NUM> of the sleeve <NUM> may be configured such that removing or fracturing some or all of the tabs <NUM> to increase the radial elasticity of the sleeve <NUM> substantially does not affect the elasticity or rigidity of the sleeve <NUM> in the longitudinal direction. In this manner, a user may remove or fracture certain tabs <NUM> to provide the sleeve <NUM> with a desired degree of radial elasticity (to accommodate a certain formation to be cored) while not affecting the longitudinal elasticity of the sleeve <NUM>, and thus not compromising the rigidity of the sleeve <NUM> in the longitudinal direction.

In other embodiments, increased radial elasticity of the sleeve <NUM> may be provided by a one or more link arrangements formed in the sleeve <NUM>. <FIG> illustrates a view of a single link arrangement <NUM> formed in the sleeve <NUM>, however, it is to be appreciated that each slot <NUM> of the sleeve <NUM> may include a plurality of link arrangements <NUM> interposed between slot segments <NUM>, similarly as described above in relation to the tabs <NUM> shown in <FIG>. As shown in <FIG>, a slot <NUM> may extend longitudinally through the wall <NUM> of the sleeve <NUM> in a direction from the upper end <NUM> of the sleeve <NUM> to the lower end <NUM> of the sleeve <NUM>, substantially separating a first circumferential section 120a of the sleeve <NUM> from a second circumferential section 120b of the sleeve <NUM> located on opposite circumferential sides of the slot <NUM>. The link arrangement <NUM> may connect the first circumferential section 120a and the second circumferential section 120b of the sleeve <NUM>.

The slot <NUM> may include at least two (<NUM>) segments, such as an upper segment <NUM>10d and a lower segment <NUM>10e, separated from one another by a formation of material of the wall <NUM> of the sleeve <NUM>. A forked lower portion <NUM> of the upper slot segment <NUM>10d may branch out and include slot branches 110f, <NUM> extending parallel with, and on either circumferential side of, an upper end portion <NUM> of the lower slot segment 110e, wherein the slot branches 110f, <NUM> provide a degree of longitudinal overlap between the lower portion <NUM> of the upper slot segment 110d and the upper portion <NUM> of the lower slot segment 110e. The link arrangement <NUM> may include a portion of material of the sleeve wall <NUM> extending circumferentially and longitudinally between the forked lower portion <NUM> of the upper slot segment 110d and the upper potion <NUM> of the lower slot segment 110e. For example, as shown in <FIG>, the link arrangement <NUM> may include a wall portion <NUM> extending longitudinally between an upper end <NUM> of the lower slot segment 110e and a lower base portion <NUM> of the forked lower portion <NUM> of the upper slot segment 110d. The link arrangement <NUM> may also include a first longitudinal wall portion <NUM> extending parallel with and circumferentially between the upper portion <NUM> of the lower slot segment 110e and one of the slot branches 110f of the forked lower portion <NUM> of the upper slot segment <NUM>10d on a first circumferential side of the lower slot segment 110e. The link arrangement <NUM> may also include a second longitudinal wall portion <NUM> extending parallel with and circumferentially between the upper portion <NUM> of the lower slot segment 110e and the other of the branches <NUM> of the forked lower portion <NUM> of the upper slot segment 110d on a second circumferential side of the lower slot segment 110e opposite the first circumferential side. Each of the first and second longitudinal wall portions <NUM>, <NUM> of the link arrangement <NUM> may extend a length D<NUM> from the lower base portion <NUM> of the upper slot segment 110d to the lower end <NUM>, <NUM> of an associated branch portion 110f, <NUM> of the forked lower portion <NUM> of the upper slot segment 110d. While <FIG> illustrates that each of the first and second longitudinal wall portions <NUM>, <NUM> of the link arrangement <NUM> have the same length D<NUM>, it is to be appreciated that the first and second longitudinal wall portions <NUM>, <NUM> of the link arrangement <NUM> may have differing lengths, as determined by the longitudinal lengths of the slot branches <NUM>10f, <NUM>.

The length Di and circumferential width of each of the first and second longitudinal wall portions <NUM>, <NUM>, as well as the circumferential width of the slot segments 110d, 110e, including the slot branches 110f, <NUM> of the upper slot segment 110d, may each be sized and configured to provide the sleeve <NUM> with a predetermined degree of radial elasticity. It is to be appreciated that the link arrangement of <FIG> embodies one possible link arrangement <NUM> design, while other link arrangement designs are also within the scope of the present disclosure. Other non-limiting examples of link arrangements are shown in <FIG>, which may include fewer than or more than two longitudinal wall portions, similar to the wall portions <NUM>, <NUM> shown in <FIG>. Additionally, the wall portions <NUM> of <FIG> may vary in length D<NUM>, orientation and shape from those shown in <FIG>.

Additionally, it is also to be appreciated that link arrangements, such as the link arrangement <NUM> of <FIG>, may be used in combination with the tabs <NUM> described in reference to <FIG> to provide the sleeve <NUM> with an overall adjustable radial elasticity. Moreover, the radial elasticity of the sleeve <NUM> may be further increased by removing or fracturing portions of the link arrangements <NUM>.

<FIG> illustrates an example beyond the wording of the claims of the sleeve <NUM> separated into four (<NUM>) circumferential sections <NUM> separated by four (<NUM>) slots <NUM> formed through the wall <NUM> of the sleeve <NUM> and extending from the upper end <NUM> of the sleeve <NUM> to the lower end <NUM> of the sleeve <NUM>. Accordingly, each circumferential sleeve section <NUM> includes a portion of each of the upper and lower ends <NUM>, <NUM> of the sleeve <NUM> and extends substantially continuously from the upper end <NUM> to the lower end <NUM> of the sleeve <NUM>. In such an example, the tubular sleeve <NUM> is not a single integral sleeve, but comprises separate, mutually adjacent circumferential sleeve sections <NUM>. The slots <NUM> may be substantially parallel to the sleeve axis, as shown in <FIG>, or may follow any direction along the length of the sleeve, as shown in <FIG>. With continued reference to <FIG>, the sleeve <NUM> may include a first sleeve section 140a, a second sleeve section 140b, a third sleeve section 140c, and a fourth sleeve section 140d. An annular sponge layer <NUM> may be attached to the inner surface of each of the sleeve sections 140a, 140b, 140c, 140d by an adhesive or other attachment means. While <FIG> illustrates the tubular sleeve <NUM> formed of four (<NUM>) sleeve sections 140a, 140b, 140c, 140d, it is to be appreciated that the sleeve <NUM> may comprise fewer or more than four (<NUM>) sleeve sections. For example, the sleeve <NUM> may include as few as two (<NUM>) sleeve sections <NUM>. In other examples, the sleeve <NUM> may include five (<NUM>) sleeve sections <NUM>. In further examples, the sleeve <NUM> may include eight (<NUM>) or more sleeve sections <NUM>. The present disclosure does not contemplate an upper limit to the amount of sleeve sections <NUM> forming the tubular sleeve <NUM> of the sponge liner.

With continued reference to <FIG>, in addition to having the sponge layer <NUM> attached to an inner surface <NUM> thereof, the sleeve sections <NUM> may be further coupled together by a plurality of external wire springs <NUM> extending circumferentially around the sleeve <NUM>. The external wire springs <NUM> may be located within and extend through circumferential grooves or channels <NUM> formed in the outer surface <NUM> of the sleeve sections <NUM>. While the sleeve <NUM> shown in <FIG> is configured to include three (<NUM>) external wire springs <NUM> extending circumferentially around the sleeve <NUM> to further couple the sleeve sections <NUM> together, only two (<NUM>) of the external wire springs <NUM> are shown, while a circumferential channel <NUM> having no external wire spring <NUM> therein is shown for illustrative purposes. It is to be appreciated that the sleeve <NUM> of <FIG> may be configured to accommodate more or less than three (<NUM>) external wire springs <NUM>. For example, in some embodiments, a sleeve <NUM>, such as the one shown in <FIG>, may have as few as one circumferential channel <NUM> formed in the outer surfaces <NUM> of the sleeve sections <NUM> for housing a single external wire spring <NUM>. In other examples, the sleeve <NUM> may have five (<NUM>) circumferential channels <NUM> formed in the outer surfaces <NUM> of the sleeve sections <NUM> for housing five (<NUM>) external wire springs <NUM>. In further examples, the sleeve <NUM> may have eight (<NUM>) circumferential channels <NUM> formed in the outer surfaces <NUM> of the sleeve sections <NUM> for housing eight (<NUM>) external wire springs <NUM>. In yet other examples, the sleeve <NUM> may have ten (<NUM>) or more circumferential channels <NUM> formed in the outer surfaces <NUM> of each of the sleeve sections <NUM> for housing ten (<NUM>) or more external wire springs <NUM>. Of course, springs of other materials and shape, such as elastomeric springs or rings, may also be employed. In other examples, other elastic elements could be used to couple the sleeve sections <NUM>. For example, such elastic elements may comprise one or more of a mesh, a fabric, a hose, or other elastic structures.

It is also to be appreciated that the sleeve sections <NUM> may be coupled together by other fastening devices, including clamps, screws, bolts, or other mechanical fasteners. Such mechanical fasteners may be fractured or uncoupled, in a similar manner as previously described, prior to a coring run to provide the sleeve <NUM> with greater elasticity if so desired. In other examples, the sleeve sections <NUM> may be coupled by an elastic material, such as a silicone or other polymer, located in the slots between adjacent sleeve sections <NUM> and adhering to side walls of the adjacent sleeve sections <NUM> in a manner to elastically bond the sleeve sections <NUM> together. Other fastening means for elastically coupling the sleeve sections <NUM> together are also within the scope of the present disclosure.

In other examples, as shown in <FIG>, the sponge layer <NUM> may be formed to extend radially outwardly into and within the slots <NUM> and to adhere to side walls of adj acent sleeve sections <NUM> as well as to inner surfaces of the sleeve sections <NUM>. In this manner, each of the sleeve sections <NUM> may be coupled to the sponge layer <NUM> at the inner surfaces <NUM> and side walls of each of the sleeve sections. In such examples, the overall integrity of the sleeve <NUM> may be maintained by the sleeve sections <NUM> and the sponge layer <NUM> without the need for any additional fastening mechanism or means for coupling the sleeve sections <NUM> together. In yet other examples, as shown in <FIG>, the sponge layer <NUM> may not extend into and within the slots <NUM> or adhere to the side walls of the sleeve sections <NUM>. In such examples, the sponge layer <NUM> links the sleeve sections <NUM> together. In other examples, the sponge layer <NUM> may extend partially into and within the slots <NUM> and may adhere to portions of the side walls of the sleeve sections <NUM> to which the sponge layer <NUM> is in contact. The increased circumferential elasticity in examples as described in this paragraph may result from the elasticity of the sponge material coupling the sleeve sections <NUM>.

In other embodiments, as shown in <FIG>, a liner <NUM> may be constructed of a multitude of individual segments <NUM>, which are combined to cover a substantially full circumference. Individual liner sleeve segments <NUM> may have overlapping areas <NUM> in a circumferential direction, to maintain a substantially cylindrical outer shape of the liner <NUM>, while allowing a change in the circumference. For example, the individual liner sleeve segments <NUM> may each have a protrusion <NUM> extending within a recess <NUM> of an adjacent liner sleeve segment <NUM> to form the overlapping areas <NUM>. These overlapping areas <NUM> in may extend in longitudinal direction over only a portion or over the entirety of the longitudinal length of the liner <NUM>. For example, as shown in <FIG>, the protrusions <NUM> and associated recesses <NUM> of the liner sleeve segments <NUM> may be located at distinct longitudinal positions of the liner <NUM> and may be squared, rounded, or shaped according to any of various other shapes. Portions of the overlapping areas <NUM> may be configured to substantially maintain the liner sleeve segments <NUM> mutually at the same longitudinal location. Additionally, the protrusions <NUM> may transmit forces to the recesses <NUM> in a direction substantially parallel to the longitudinal axis L of the liner <NUM>. Referring again to <FIG>, associated absorptive layers <NUM> of the liner segments <NUM> may also have areas <NUM> overlapping in a circumferential direction. For example, the absorptive layer segments <NUM> may each have a protrusion <NUM> extending within a recess <NUM> of an adjacent absorptive layer segment <NUM>. As with the liner sleeve segments <NUM> shown in <FIG>, the protrusions <NUM> and associated recesses <NUM> of the absorptive layer segments <NUM> may be located at distinct longitudinal positions of the liner <NUM> and may have various shapes and configurations. These overlapping areas <NUM> and <NUM> of the liner sleeve segments <NUM> and the absorptive layer segments <NUM> may ensure that there is no open fluid passage from an inner surface <NUM> of the liner <NUM> towards an outer periphery <NUM> of the liner <NUM>, where the formation fluid of interest may become lost for further analysis. Additionally, the protrusions <NUM> may transmit forces to the recesses <NUM> in a direction substantially parallel to the longitudinal axis L of the liner <NUM>. As shown in <FIG>, the individual liner segments <NUM> may be held together by elastic elements (not shown) located in circumferential grooves <NUM> formed in the outer periphery <NUM> of the liner sleeve segments <NUM>, as previously described, by way of non-limiting example.

Claim 1:
A liner tube for a core barrel assembly, comprising:
a sleeve (<NUM>) having an inner surface (<NUM>) configured to be coupled to a layer of material (<NUM>) configured to absorb or adsorb formation fluids or parts of formation fluids, the sleeve (<NUM>) being substantially cylindrical, wherein, at every longitudinal location of the sleeve with respect to a longitudinal axis of the sleeve, a transverse cross-section of a wall of the sleeve includes at least one gap (<NUM>) extending radially through the entire wall of the sleeve (<NUM>), the at least one gap (<NUM>) separating a portion (120a) of the sleeve wall on one circumferential side of the at least one gap (<NUM>) from another portion (120b) of the sleeve wall on an opposite circumferential side of the at least one gap (<NUM>), and the sleeve (<NUM>) having a flexibility in a circumferential direction greater than that of a sleeve (<NUM>) without a gap (<NUM>) extending radially through an entire wall of the sleeve (<NUM>) at a transverse cross-section of the sleeve (<NUM>) at every longitudinal location of the sleeve (<NUM>);
wherein the at least one gap (<NUM>) comprises at least one slot (<NUM>) formed in an outer surface of the sleeve (<NUM>), each slot (<NUM>) extending completely radially through a wall of the sleeve (<NUM>) from an outer surface (<NUM>) of the sleeve (<NUM>) to the inner surface (<NUM>) of the sleeve (<NUM>), at least a portion of the slot (<NUM>) extending longitudinally discontinuously along at least a portion of an entire length of the sleeve (<NUM>), wherein the slot (<NUM>) comprises a plurality of segments (<NUM>), and one or more formations of material of the wall of the sleeve (<NUM>) separate the segments (<NUM>) of the slot (<NUM>).