WO2014179689A1

WO2014179689A1 - Orientable perforating devices

Info

Publication number: WO2014179689A1
Application number: PCT/US2014/036580
Authority: WO
Inventors: Vinod CHAKKA; Pedro Hernandez; Raphael Rogman
Original assignee: Schlumberger Canada Ltd; Services Petroliers Schlumberger SA; Schlumberger Technology BV; Schlumberger Technology Corp; Schlumberger Holdings Ltd; Prad Research and Development Ltd
Current assignee: Schlumberger Canada Ltd; Services Petroliers Schlumberger SA; Schlumberger Technology BV; Schlumberger Technology Corp; Schlumberger Holdings Ltd; Prad Research and Development Ltd
Priority date: 2013-05-03
Filing date: 2014-05-02
Publication date: 2014-11-06
Anticipated expiration: 2015-11-03
Also published as: AR096189A1

Abstract

Wellbore perforating devices are disclosed. Some embodiments may take the form of a perforating device having a loading tube with a plurality of apertures therein. Shaped charges may be installed into the apertures using jackets. Each jacket holds one shaped charges and is insertable into the apertures. Upon insertion into the apertures the jackets orient the shaped charges to a selected orientation.

Description

ORIENT ABLE PERFORATING DEVICES

BACKGROUND

[0001] To enhance production from a subterranean formation, a perforating gun is lowered into a wellbore extending through the formation. Radially oriented shaped charges on the perforating gun are detonated to perforate the surrounding well casing and formation to enhance or facilitate the initiation and propagation of transverse-to-wellbore fractures.

SUMMARY

[0002] The present application discloses devices for wellbore perforating, and more specifically discloses perforating devices for optimizing downhole transverse fracturing to thereby maximize reservoir contact. In one example, a wellbore perforating device includes a Some embodiments may take the form of a perforating device having a loading tube with a plurality of apertures therein. Shaped charges may be installed into the apertures using jackets. Each jacket holds one shaped charges and is insertable into the apertures. Upon insertion into the apertures the jackets orient the shaped charges to a selected orientation.

[0003] Other embodiments may take the form of a shaped charge jacket having an interior volume into which a shaped charge may be received. The interior volume may include a lower tapered portion and an open upper portion through which the shaped charge is received. An upper exterior extends from the upper portion of the interior volume having a non-planer, oval shape. The upper exterior includes a rear portion extends further from the lower tapered portion of the interior volume than a front portion. A loading tube engagement member extends from an outside of the lower tapered portion of the interior volume.

[0004] Further examples and alternatives are described herein below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 depicts one example of a wellbore perforating device disposed in a horizontal well that extends into a subterranean formation.

[0006] Figure 2 is a side view of a section of a wellbore perforating device.

[0007] Figure 3 is a side view of two sections of a wellbore perforating device.

[0008] Figure 4 is a sectional view of two sections of a wellbore perforating device.

[0009] Figure 5 is an end view of a plurality of shaped charges.

[0010] Figures 6-15 depict various view of a shaped charge jacket. [0011] Fig. 16 depicts a side view of a carrier holding a loading tube with jackets installed therein.

[0012] Fig. 17 depicts an end view of the carrier holding a loading tube with jackets installed therein of Figure 16.

DETAILED DESCRIPTION OF THE DRAWINGS

[0013] In the following description, certain terms have been used for clearness and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of prior art because such terms are used for descriptive purposes and are intended to be broadly construed. The different devices and methods described herein may be used alone or in combination with other devices and methods. It is to be expected that various equivalents, alternatives, and modifications are possible within the scope of the appended claims. For example, although Figure 1 depicts a cased horizontal wellbore, the perforating devices disclosed herein can be used in cased or uncased vertical or other non- horizontal wellbores and in a variety of underground formations. Although the Figures depict certain types and sizes of shaped charges, the present disclosure contemplates that different sizes and different types of charges could be used alone or in combination with other sizes and types of charges. Further, although the Figures depict holders that hold the charges at certain angles with respect to each other and with respect to the length of the holder, the present disclosure contemplates that the charges could be held by different holder configurations and at different angles with respect to each other and with respect to the holder. Although the Figures depict certain numbers of charges and numbers of perforating gun sections, the present disclosure contemplates that more or fewer charges and perforating gun sections could be used. Further variations of the structures depicted and described herein are contemplated within the scope of the present disclosure and within the scope of the appended claims.

[0014] As used herein, the terms "above" and "below"; "up" and "down"; "upper" and

"lower"; "upwardly" and "downwardly"; and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe some examples. However, when applied to equipment and methods for use in wells that are deviated from vertical or horizontal, such terms may refer to a left to right, right to left, or diagonal relationship, as appropriate. [0015] Figure 1 depicts a perforating gun 10 disposed in a casing 12 of a horizontal wellbore 14 extending through an underground formation 16. The gun 10 is depicted in isolation, but as will be understood by one or ordinary skill in the art, typically will be connected to known varieties of production equipment, such as coiled tubing conveyances or the like, for selectively positioning perforating devices in wellbores. The gun 10 includes a plurality of sections 18a, 18b, etc. Each section 18a, 18b includes a holder 20 for holding a plurality of shaped charges 22a, 22b, 22c for detonation. The number of sections and the number of shaped charges in each section can vary from that depicted. As will be described further herein below, upon detonation the charges 22a, 22b, 22c in each section 18a, 18b form jets that are projected from the holder 20 and travel along a predetermined pathway Wl, W2, W3, respectively, so as to intersect a common plane P extending transversely from the holder 20 at a predetermined radial distance from the wellbore, and to thereby enhance the initiation and formation of either a transverse fracture F or a pseudo tilted longitudinal-to- transverse fracture through the casing 12 and into the formation 16 from the wellbore 14. Examples having multiple sections 18a, 18b, etc. can be configured to form jets that intersect different planes PI, P2, etc. to form multiple transverse fractures Fl, F2, (for example, extending fractures both up and down in a horizontal wellbore) etc.

[0016] Figure 2 depicts one exemplary section 18b of the gun 10. The section 18b includes a holder 20 that holds a plurality of shaped charges 22a, 22b, 22c. The holder 20 is elongated in a longitudinal direction L and includes a plate-like member having cavities for holding the plurality of charges 22a, 22b, 22c in a spaced apart orientation along the longitudinal direction L. Other non-plate-like configurations of the holder 20 are possible with the scope of this disclosure. The plurality of charges 22a, 22b, 22c, includes a pair of outer charges 22a, 22c and an inner charge 22b disposed between the pair of outer charges 22a, 22c in the longitudinal direction L. Each outer charge 22a, 22c is tilted towards the inner charge 22b with respect to the longitudinal direction L. This is more clearly depicted in the section view of the example of Figure 4 by tilt angle T.

[0017] As shown in Figure 2, the inner charge 22b is held by the holder 20 at a generally perpendicular orientation to the longitudinal direction L such that upon detonation, the inner charge 22b forms a jet that is propelled generally perpendicularly to the holder 20 in a radial direction R and along plane P2 extending perpendicularly to the holder 20. This is more clearly depicted in the perspective view of Figure 2 by W2. The outer charges 22a, 22c are tilted towards the inner charge 22b at tilt angle T and thus upon detonation form jets that travel towards and intersect with the plane P2. Thus upon detonation, each of the charges 22a, 22b, 22c form a jet that intersects the common plane P2 extending transversely to the holder 20 at a predetermined radial distance D from the wellbore 14. The angle of tilt T of the outer charges 22a, 22c can vary and can be specifically selected to achieve an intersection by the jets of the outer charges 22a, 22b with the plane P2 at a predetermined radial distance D from the wellbore 14. For example, in some circumstances, the jets of the outer charges 22a, 22c may intersect the common plane P2 at the location where a sand face exists surrounding the wellbore casing 12. In another example, the jets of the charges 22a, 22b, 22c could intersect the common plane P2 at a distance between the sand face and one wellbore diameter. By selecting an appropriate angle of tilt T of the outer charges 22a, 22c, this radial intersection location with plane P2 can advantageously be achieved. Although the drawing figures depict a perpendicular orientation for inner charge 22b, the orientation of the inner charge 22b does not necessarily have to be perpendicular to the holder 20. As understood from the comments above, the various tilt angles of each of the charges 22a, 22b, 22c can be varied to achieve different objectives depending upon the well environment and particular fracturing objectives.

[0018] In some embodiments, a charge holder may take the form of a loading tube, such as the loading tube 32 shown in Figure 4. The loading tube 32 may include a plurality of apertures 26, 28 into which a jacket 30 and a shaped charge 22a, 22b, 22c may be inserted. More specifically, a first set of apertures (e.g., apertures 27) may be located on a first side of the loading tube 32 and perforating jets may be produced out of the first side of the loading tube. A second set of apertures (e.g., apertures 28) may be located on a second side of the loading tube 32, generally opposite from the first side. The each aperture 28 of the second set of apertures may correspond to an aperture 27 of the first set of apertures and may receive at least a portion of a lower end of a jacket, as discussed in greater detail below. In some embodiments, apertures 26, 28 may be keyed apertures which have a shape or size which corresponds with a shape or size of the jacket received therein to help aid in orienting the jacket and shaped charge. For example, the aperture may be slotted, have a slotted region or have an indented portion. The slot, slotted region or indented portion may receive a corresponding rib, ribs, or protrusion on the jacket. In some embodiments, one or more apertures 28 of the second set of apertures may be keyed.

[0019] Figure 5 is an end view of a section 18b of a plurality of charges and further depicts the phasing of the charges 22a, 22b, 22c with respect to each other at azimuth angles, e.g., Al, A2. Such phasing is an optional feature and the angle of phasing can vary and be specifically selected to achieve a desirable path of travel of the jets formed by charges 22a, 22b, 22c. In the example shown, the charges 22a, 22b, 22c are phased about the longitudinal direction L by azimuth angles Al, A2. While the charges 22a, 22b, 22c are held in the phased relationship defined by the holder 20 (Figure 2), the azimuth angles Al, A2 are more readily identifiable by a comparison of the projection jet pathways Wl, W2, W3, as depicted in Figure 5. In some examples, the outer charges 22a, 22c are azimuthally phased within 15 degrees of the inner charge 22b. In other examples, the outer charges 22a, 22c, are azimuthally phased within 30 degrees of the inner charge 22b. In other examples, the outer charges 22a, 22c are azimuthally phased within 120 degrees of the inner charge 22b. Phasing of shaped charges is described in more particularity in U.S. Patent Nos. 5,392,857 and 6,397,947, which are incorporated herein by reference.

[0020] Figures 1, 3 and 4 depict presently preferred examples of a gun 10 having first and second sections 18a, 18b connected together in series. Specifically, each gun section 18a, 18b includes a holder 20 that holds a respective plurality of shaped charges 22a, 22b, 22c such that upon detonation of each plurality of shaped charges 22a, 22b, 22c, the predetermined jet pathway Wl, W2, W3 of each charge in a respective plurality intersects a common plane, i.e. PI or P2, extending transversely to the wellbore 14 at a predetermined radial distance D. The holders 20 in the first and second gun sections 18a, 18b are arranged such that upon detonation the predetermined jet pathways Wl, W2, W3 of each respective plurality of shaped charges 22a, 22b, 22c intersect a different common plane PI or P2. As with the example depicted in Figure 2, each plurality of shaped charges 22a, 22b, 22c depicted in Figures 1, 3 and 4 comprises a pair of outer charges 22a, 22c and an inner charge 22b disposed between the pair of outer charges 22a, 22c in the longitudinal direction L. The inner charge 22b is preferably held by the holder 20 at a generally perpendicular orientation to the longitudinal direction L such that upon detonation the jet of the inner charge 22b travels outwardly from the holder 20 in a radial direction R that is substantially perpendicular to the longitudinal direction L.

[0021] In the examples of Figures 1, 3 and 4, each gun section 18a, 18b containing a plurality of shaped charges 22a, 22b, 22c can be azimuthally aligned or azimuthally phased with respect to other gun sections in the perforating gun 10. In the examples of Figures 1, 3, and 4, the first and second gun sections 18a, 18b are azimuthally phased at an angle of 180 degrees, such that the jet of the inner charge 22b in the first gun section 18a travels in the radial direction R that is azimuthally angled at 180 degrees with respect to the direction of travel of the jet of the inner charge 22b in the second gun section 18b. The azimuth angle between gun sections can vary and can be preselected to achieve predetermined directions of travel for each jet of the plurality of shaped charges 22a, 22b, 22c. As in the examples described above, each outer charge 22a, 22c is tilted towards the inner charge 22b in the longitudinal direction, by a tilt angle T. Again, the tilt angle T can vary and be preselected to achieve performance objectives.

[0022] Phasing of the gun sections 18a, 18b at an angle with respect to the azimuth can have advantages in certain situations. For example, evenly phasing a series of gun sections, for example a series of six gun sections phased at 60 degree intervals, respectively, provides a perforating gun that does not require special orientation in the wellbore. That is, transverse fractures at 60 degree intervals circumferentially around the wellbore will be achieved regardless of the rotational position of the gun 10 disposed in the wellbore 14. Alternate phasing, for example at a series of four gun sections phased at 90 degree intervals or a series of three gun sections phased at 120 degree intervals can be employed to achieve similar results wherein the perforating gun does not require special rotational orientation in the wellbore. This allows for non-oriented transverse fracturing at selected circumferential locations of the wellbore.

[0023] Figures 2 and 3 also depict a clip 24 for connecting two adjacent gun sections

18a, 18b. Each gun section 18a, 18b includes opposing end flanges 26a, 26b configured to mate with a flange of an adjacent gun section. Each flange has at least one of a male or female part (not shown) for connecting with at least one of a corresponding male or female part on an adjacent flange. The clip 24 is configured to engage the opposing end flanges 26a, 26b to secure connection therebetween. In the example depicted, the clip 24 is C-shaped and includes an inner channel 28 sized to fit around the end flanges 26a, 26b when joined together. In a one example, more than one male or female parts on the end flanges 26a, 26b are circumferentially spaced apart from each other around the respective end flange so as to allow for selective rotational positioning of the gun section 18a, 18b at predetermined angles of rotation with respect to an adjacent gun section. This allows for easier selection of the above noted azimuth angle between the adjacent gun sections 18a, 18b. Other structural equivalents could be employed to achieve this selectivity.

[0024] Figures 6-14 illustrate various views of a jacket 30 that may be used to orient the shape charges in a gun. The jacket 30 may be made of any suitable material, such as a plastic or resin, for example. The jacket 30 may be formed by any suitable manufacturing, such as for example, a molding process, a machining process, or a printing process. Additionally, the jacket 30 or parts of the jacket may be formed from one or more different processes. In some embodiments, the jacket 30 may directly engage a tubular, such as a loading tube or a gun, to be secured therein. That is, the jacket 30 may be installed directly into an aperture of a loading tube, as discussed above with reference to Figure 4. Also, the jacket 30 may be configured to secure a shaped charge. Specifically, the jacket 30 may be formed to define a interior volume into which a shaped charge may be secured. Generally, the jacket 30 may have a shape similar to that of a shaped charge, with a wide upper opening and a tapered lower portion. Various features to both secure a shaped charge and to secure the jacket into a tubular are discussed in greater detail below.

[0025] The jacket 30 may also orient the charge so that it is azimuthally phased within a selected angular range of an inner charge. In some embodiments, the charge holder may be used to secure and orient two of a set of three shaped charges. The orientation of the set of shaped charges may generally be such that the perforating jets form a spiral fan pattern. For example, a center charge may be oriented to create a perforating jet that is normal to a guns longitudinal axis. Charges on either side of the center charge may be oriented so that they create perforating jets angled towards that of the center shaped charge longitudinally, but also angled away from each other radially so that the perforating jets form an opposing spiral fan pattern. In some embodiments, the charges may be oriented by the jacket to form other perforating jet patterns. Indeed, the jackets 30 and the loading tube 32 may be configured to allow for movement and orientation of the charges along multiple axes. For example, the charges may be selectively oriented in a desired orientation relative to a longitudinal axis and in a desired orientation relative to a radial position. For example, in some embodiments, the charges may be oriented to converge together both longitudinally and radially.

[0026] Referring to Fig. 6 a front view of the jacket 30 is illustrated. The jacket 30 may include a frontal tab 38 extending from the front of the jacket and a rear tab 40 extending from the rear of the jacket. Each of the front and rear tabs 38, 40 may be configured to allow the jacket 30 to enter into the aperture 27 and then engage the loading tube to secure the jacket therein. Figure 7 depicts a side view of the jacket 30 and the frontal and rear tabs 38, 40 may be seen. Figure 8 depicts a back view of the jacket and shows the rear tab 38.

[0027] Additionally, the jacket 30 include a plurality of shaped charge securement members. In one embodiment, a pair of tab reliefs 42 are positioned near the front of the jacket equidistant from a centerline of the jacket. The tab reliefs 42 have relief cuts into the sidewall of the jacket to allow movement of the tabs as a shaped charge is inserted into the jacket 30. These relief cuts 43 may better be seen in Figure 9. A clip tab 44 may be positioned on a rear wall of the jacket. In some embodiments, more or fewer shaped charge securement members may be provided and may be provided at various different locations. Generally, in accordance with some embodiments, the shaped charge securement tabs may protrude into an inner volume of the jacket 30 to engage a shaped charge. In some embodiments, the securement tabs may engage a top of a shaped charge, while in other embodiments, the tabs may engage a notch or groove in a sidewall of a shaped charge.

[0028] Figure 10 illustrates a cross-sectional view taken along line ΙΧ-ΓΧ in Figure 7.

This view shows both the rear tab 38 for engagement of the loading tube and the clip tab 44 on the inner, rear wall of the jacket 30. Figure 1 1 is a cross-sectional view taken along line X-X in Figure 6 and shows the clip tab 44, as well as the front tab 38.

[0029] The jacket 30 may also include a lower engagement feature 46. The lower engagement feature 46 may generally extend from and be coupled to the lower tapered portion of the jacket. The lower engagement feature 46 may include one or more geometric shapes that may engage a loading tube. In particular, a loading tube may be keyed or deigned to allow coupling with a particular shaped object. The lower engagement feature may include complimentary features to fit into a keyed aperture of the loading tube. As shown in Figures 6-15, the lower engagement feature 46 may have one or more ribs 48. As such, they may engage a slot, slots, or cutaways of a loading tube. The ribs 48 may be oriented in a crossing pattern in some embodiments. Additionally, in some embodiments, one or more ribs 48 may include a step profile 50 so that a portion of the rib may be inserted into a corresponding aperture in a loading tube and the remainder of the rib remains within the loading tube. Further, the lower engagement feature may have a shape that it corresponds with a side wall of the loading tube when installed within the loading tube. For example, in Figure 15, the lower engagement feature is shown as having an acute angle profile that provides a planer surface that is non-parallel with the lower surface of the jacket from which the lower engagement feature extends. It should be appreciated that the lower engagement feature 46 may generally take any suitable form and various different patterns, shapes and sizes may be implemented to achieve a desired engagement with the loading tube. The lower engagement feature 46 may be used to help ensure a proper orientation of the shaped charges in some embodiments. [0030] The lower engagement feature may further include a via 52 therethrough through which a detonating cord may pass. The via 52 may generally be located at a base of the lower tapered portion of the jacket so the detonating cord may be adjacent to the base of the shaped charge when installed in the jacket.

[0031] Figures 16 and 17 depict a side view and an end view, respectively, of a loading tube 60 in a carrier 62, with the jackets 70 installed therein. As shown, the jackets 70 may provide both longitudinal movement and radial movement within the loading tube 60, so that charges within the jackets may be oriented in any desired manner. That is, the jackets 70 may move be oriented according to longitudinal (or polar) angle and a radial (or azimuth) angle φ.

[0032] In certain examples depicted, perforation is accomplished in a manner that enhances creation of transverse fractures. Pressures required to break down fractures are reduced and connectivity between the created fracture and perforating holes in the well casing and pipe are increased. In many environments, natural bedding planes and extreme textures in, for example, gas shales require pinpoint perforation to initiate fractures. In some embodiments, the shaped charges may be oriented in such a manner that upon detonation of the charges, the jets intersect a common plane extending transversely to the holder. The particular orientations about the azimuth and tilt angles can be manipulated depending upon the specific geography being fractured. In addition, different types of charges (e.g. deep penetration charges or big hole charges) can be used in combination to achieve predetermined fracturing criteria.

Claims

CLAIMS What is claimed is:

1. A perforating device comprising:

a loading tube having a plurality of apertures therein;

a plurality of shaped charges installed into the plurality of apertures; and

a plurality of jackets, each holding one of the plurality of shaped charges, the jackets insertable into the apertures, wherein upon insertion into the apertures the jackets orient the shaped charges to a selected orientation.

2. The perforating device of claim 1, wherein the plurality of apertures comprises a pair of apertures on opposite sides of the loading tube for each shaped charge.

3. The perforating device of claim 2, wherein at least one of the pair of apertures is keyed to orient the jackets within the apertures.

4. The perforating device of claim 1, wherein the jackets comprise ribs which engage a keyed aperture of the loading tube to orient the jackets and the shaped charges within the loading tube.

5. The perforating device of claim 1, wherein the jacket further comprises a detonating cord securement member by which a detonating cord is secured.

6. The perforating device of claim 5, wherein the detonating cord securement member comprises a via located to place the detonating cord proximate to a shaped charge.

7. The perforating device of claim 1, wherein the jackets comprise engagement members to secure the jacket within an aperture of the loading tube.

8. The perforating device of claim 7, wherein the engagement members comprise:

a frontal tab extending from the front of the jackets; and

a rear tab extending from the rear of the jackets.

9. The perforating device of claim 1, wherein the jackets comprise a plurality of shaped charge engagement members extending inwardly into the jacket to secure a shaped charge.

10. The perforating device of claim 9, wherein the shaped charge engagement members comprise:

at least one tab relief positioned near a front of the jacket; and

at least one rear tab.

1 1. The perforating device of claim 9, wherein the shaped charge engagement members comprise: a pair of tab reliefs positioned equidistant from a centerline of the front of the jackets; and

at least one rear tab.

12. A shaped charge jacket comprising:

an interior volume into which a shaped charge is received, the interior volume including a lower tapered portion, and an open upper portion through which the shaped charge is received;

an upper exterior extending from the upper portion of the interior volume having a non-planer, oval shape, the upper exterior including a rear portion extending further from the lower tapered portion of the interior volume than a front portion; and

a loading tube engagement member extending from an outside of the lower tapered portion of the interior volume.

13. The shaped charge jacket of claim 12, wherein the interior volume comprises a plurality of shaped charge securing members extending inwardly into the interior volume.

14. The shaped charge jacket of claim 13, wherein the plurality of shaped charge securing members comprises at least one tab relief member.

15. The shaped charge jacket of claim 13, wherein the plurality of shaped charge securing member comprises at least one tab extending inwardly from a rear wall of the interior volume.

16. The shaped charge jacket of claim 12, wherein the upper exterior comprises a plurality of loading tube engagement members.

17. The shaped charge jacket of claim 16, wherein the plurality of loading tube engagement members comprise:

at least one frontal loading tube engagement member; and

at least one rear loading tube engagement member, wherein the loading tube engagement members are configured to maintain an outer surface of the jacket within an outer diameter of an outer surface of a loading tube.

18. The shaped charge jacket of claim 12, wherein the loading tube engagement member comprises at least one rib for engaging a loading tube.

19. The shaped charge jacket of claim 12, wherein the a loading tube engagement member comprises a via adjacent to the outer wall of the lower tapered portion of the interior volume.

20. A method of installing charges into perforating gun comprising:

securing a charge into a jacket; passing a detonating cord through a base of the jacket;

installing the jacket into a loading tube, wherein installing the jacket into the loading tube orients the shaped charge to create perforating jets that cross a common plane with at least two other shaped charge perforating jets of the perforating gun; and

inserting the loading tube into a perforating gun.