Patent Application
20210348891
A perforating tool is commonly used to maximize the potential recovery of hydrocarbons, such as oil and gas obtained from subterranean formations that may be located onshore or offshore. However, for a given recovery operation, the perforating tool may be selected based on limited knowledge of the likely downhole explosive charge performance A selection of in-field perforating tool parameters may be based in part on tests performed using laboratory tools designed to evaluate explosive charge performance, e.g., by measuring depth of penetration.
Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
Disclosed herein are embodiments of a perforating tool where the free interior volume inside the tool body (also often referred herein to as free gun volume, FGV) can be readily adjusted by disposing various numbers of plates inside an interior cavity of the tool body. Adjustment of the free interior volume in turn changes the nature of the pressure response when an explosive charge inside the tool body is detonated, e.g., when used in a perforating tool testing system. In particular, the perforating tool facilitates creating a desired dynamic underbalance (DUB) or dynamic overbalance (DOB) pressure response when testing and simulating in-field perforating tool parameters.
The term DUB refers to a transient pressure condition in which the wellbore pressure during a perforating operation is less than the adjacent formation pore pressure. The term DOB refers to a transient pressure condition in which the wellbore pressure during a perforating operation is greater than the adjacent formation pore pressure.
Embodiments of the perforating tool disclosed herein are advantageous over other ways to adjust free interior volume. The plates of the tool can reduce the free interior volume to a greater degree than packing the interior cavity of the tool body with loose particles (e.g., ball bearings and/or sand), due the latter's inherent porosity. The plates can be readily put into the interior cavity of the tool body such that they are situated apart from the explosive charge, to more realistically simulate a field perforating tool which, e.g., typically does not include loose particles packed against the explosive charge. The plates can be readily taken out of the interior cavity of the tool body if it is decided at the last minute that a different FGV adjustment is desired. The ability to readily and reproducibly adjust the free interior volume by disposing a selected number of the plates inside the interior cavity of the tool body is also cost and time advantageous over having to machine a new tool body every time a specific new free interior volume is desired to be tested.
One embodiment of the disclosure is a perforating tool.
With continuing reference to
The perforating tool 100 includes one or more plates (e.g.,
Embodiments of the first lid 110 can includes an explosive charge depot 140 within the interior cavity to provide a location where the explosive charge can be disposed. For instance, the explosive charge depot 140 can be an indentation in the interior surface 137 of the first lid 110 or other mounting location on the surface 137. Embodiments of the first lid 110 can include a recess 141 to enhance operation of perforating tool 100. In some embodiments, the explosive charge depot 140 and the recess 141 can be aligned with each other.
The term air-tight seal refers to sealing elements between the first and second lids 110, 115 and the body 105, and the function they serve, e.g., when the lids are attached to the body, the entrapped fluid within the body (e.g., air) is no longer in hydraulic communication with fluid in the exterior environment surrounding the body. The term situated apart refers a surface of the nearest being a non-zero distance away from the explosive charge such than air within the interior cavity can pass between the nearest plate surface and the explosive charge. In some embodiments, a separation distance 142 between the surface of the nearest plate (e.g., surface 144 of one plate 130 in
In some embodiments, to provide a free volume space around the explosive charge 135, the one or more plates 130 are situated apart from the first lid 110. For example, in some embodiments, a separation distance 146 between the surface of the nearest plate (e.g., surface 144 of one plate 130 in
The term free interior volume (FGV) refers to the void space inside of the body's interior cavity that is not occupied by solid structures, e.g., the explosive charge, the plates or any other structures that would displace air in the interior cavity.
In some embodiments of the tool 100, to at least help provide a large adjustable FGV range, the one or more plates 130, in combination, can be configured to occupy between 0 and 100 percent of the total interior volume of the interior cavity 125. For instance, in some embodiments, the plates can be such that the total interior volume occupied by the one or more plates 130 can be greater than 0 (e.g., 0.1 or 1 percent or more) and less than 100 percent (e.g., 99 or 99.9 percent or less), greater than 10 and less than 90 percent, greater than 20 and less than 80 percent, greater than 30 and less than 70 percent, greater than 40 and less than 60 percent, or a range from 10 to 30 percent, from 30 to 60 percent, from 60 to 90 percent, or any other combination of these ranges.
In some embodiments of the tool 100, to at least help provide precise incremental adjustments to the FGV, individual ones of the plates can be sized such that any one of the plates occupy from greater than 0 to nearly 100 percent of the total interior volume. For example, the plates can be sized by adjusting the individual plate's thickness (e.g., thickness 150 or average thickness for plates with a non-planar surface, such as a surface having a depression). For example, each one plate can occupy a percentage of the total interior volume in a range from about 0.1 or 1 to nearly 100 percent (e.g., 99 or 99.9 percent), from 25 to 50 percent, from 10 to 20 percent, from 5 to 10 percent, or from 1 to 2 percent of the total interior volume. In some embodiments, each one of the plates can be equally sized and occupy a same percentage of the total interior volume e.g., 100 plates each occupying about 1 percent, 10 plates each occupying 10 percent, or 2 plates each occupying 50 percent. In other embodiments, the plates are not equally sized e.g., each plate, or different groups of plates, can be differently sized from each other so as to occupy different percentages of the total interior volume.
In some embodiments of the tool 100, to at least facilitate keeping the adjusted free interior volume constant during explosive charge detonation, the plates can be composed of a non-deformable and impermeable material. For example, the plates can be composed of aluminum, steel, or other metals, or other materials that are non-porous and non-compressible during and after the detonation of the explosive charge. In some embodiments, the plates can be solid plates, while in other embodiments the plates can include hollow portions, e.g., to reduce the material costs and weight of the plates. However, in at least one embodiment, during and following the detonation of the explosive charge, the plates remain intact and do not change shape such that the portion of the total interior volume of the interior cavity occupied by the plates is not changed. For example, expanding gases or solid material accelerated by the detonation do not permeate into the plates or change the volume occupied by the plates.
In some embodiments of the tool 100, to at least to facilitate to keep the plates apart from the explosive charge 135 and further reduce the FGV, a surface of the one plate facing and nearest (e.g., surface 144 of plate 130 in
In some embodiments of the tool 100, to facilitate reducing the FGV, at least two, and in some embodiments, all, of the one or more plates are shaped to stack together. For example, in some embodiments, a surface 144d′ of the plate 130d facing away from the explosive charge matches a surface 144c of an adjacent plate 130c. For example, in some embodiments, adjacent surfaces of the plates (e.g., surfaces 144c and 144d′) are planar surfaces.
In some embodiments of the tool 100, to at least facilitate reducing the FGV and making plates readily insertable into, or removable from, the interior cavity 125, the one or more plates (e.g., the one plate 130, or the plates 130a, . . . 130d) are shaped to fit flush against an interior wall of the body (e.g., interior body wall 105a ). For example, when the interior cavity of the body 105 is defined by a cylindrically shaped wall (e.g., wall 105a ) then the one or more solid plates can have a cylindrical shape to fit flush against the cylindrically shaped wall. For example, in some embodiments, the one of more cylindrically shaped plates can have a diameter 158 that is 0.01, 0.1, 1, 2, 5 or 10 percent or less than an internal diameter 160 of the body 105.
In some embodiments of the tool 100, to secure the plates, a surface of the second lid (e.g., internal surface 162 of the top lid 115) facing the interior cavity 125 includes a port (e.g., port 164 or a plurality of such ports) to secure a first end portion of a rod therein (e.g., first end portion 166 of rod 168). A stem portion (e.g., stem portion 170) of the rod is sized to pass through an opening in each of the one or more plates (e.g., through-hole opening 172) and a second end portion of the rod (e.g., second end portion 174) includes a stop structure sized to not pass through the one or more openings in the plate (e.g., stop structure 176, such as a wing nut or flat head bolt as illustrated in
In some embodiments of the tool 100, each of the one or more plates can include an opening (e.g., second opening 180) sized to allow a portion of a detonation cord (e.g., cord 182) there-through no connect to the explosive charge 135. The second lid 115 can include an opening 184 sized to allow a portion of a detonation cord there-through.
With continuing reference to
For some embodiments, as illustrated FIGs.1C and 1D, a surface of one plate of the two or more plates 130 that faces and is nearest to the explosive charge 135 (e.g., surface 144 of plate 130g), touches the explosive charge 135. Similar to that already discussed in the context of
In other embodiments, as discussed in the context of
The embodiments of the tool 100 having two or more plates, such as illustrated in
For example, the two or more plates in combination can occupy between 0 and 100 percent of the total interior volume of the interior cavity. Individual ones of the two or more plates can be sized such that any one of the plates occupy from at least 1 to nearly 100 percent of the total interior volume. The two or more plates can be composed of a non-deformable and impermeable material. The two or more plates can be shaped to stack together. The two or more plates can be shaped to fit flush against an interior wall of the body. A surface of the second lid facing the interior cavity can include a port to secure a first end portion of a rod therein, where a stem portion of the rod can be sized to pass through an opening in each of the two or more plates and a second end portion of the rod includes a stop structure sized to not pass through the one or more openings in the two or more plates. Each of the two or more solid plates can include an opening sized to allow a portion of a detonation cord there-though.
Similar to that discussed As discussed in the context of
The perforating tool testing system 200 includes a simulated wellbore case 210. Embodiments of the simulated wellbore case 210 can be cylindrically shaped or any suitable shape that facilitates simulation an in-field wellbore system using a laboratory perforation tool 100 of the disclosure. The system 200 includes a simulated wellbore 215 disposed within the simulated wellbore case 210 and a face plate 220 disposed at a first end 222 of the simulated wellbore. The system 200 includes a formation sample 225 disposed within the simulated wellbore case, wherein the formation sample couples to the face plate. The perforating tool testing system 200 additionally includes the laboratory perforating tool 100 disposed within the simulated wellbore 215 between the first end 222 and a second end 227 of the simulated wellbore.
As disclosed in the context of
In some embodiments, the laboratory perforating tool 100 includes one or more plates 130 disposable within the interior cavity such that the one or more plates are situated apart from an explosive charge 135 when the explosive charge is disposed in the interior cavity, the one or more plates occupying part of a total interior volume of the interior cavity and thereby reducing a free interior volume inside the body.
In other embodiments, the laboratory perforating tool 100 includes two or more plates 130 disposable within the interior cavity such that the two or more plates are situated apart from an explosive charge when the explosive charge is disposed in the interior cavity, the two or more plates occupying part of a total interior volume of the interior cavity and thereby reducing a free interior volume inside the body.
The explosive charge135 is disposed such that detonation of the explosive charge creates a perforation in the formation sample 225, and the one or more plates affect a dynamic underbalance (DUB) or dynamic overbalance (DOB) of the perforating tool testing system.
The simulated wellbore 215 can be pressurized to apply a pressure, e.g., that approximates a wellbore pressure, to the tool 100. Embodiments of the simulated wellbore 215 can comply with the API RP 19 Section 2 and Section 4 wellbore cavity requirements.
For instance, the system 200 can include one or more fluid chambers 230 disposed about the formation sample 225. The fluid chambers 230 can include fluid used to apply an overburden or an underburden pressure during a simulation to simulate overburden stress or underburden on the formation sample 225.
The perforating tool system 100 can be arranged or include various components as required to facilitate a given testing operation. A detonation cord 182 can be coupled to the explosive charge 135 of the tool 100. The detonation cord 182 can pass through an opening (e.g., opening 184 of second lid 115,
Some embodiments of the system 200 can include one or more filler discs 240 disposed within a cavity of the simulated wellbore 215 between a simulated wellbore cap 245 of the simulated wellbore 215 and the tool 100. The one or more filler discs 240 may fit flush against the interior wall 250 of the simulated wellbore 215 or be of any other suitable dimensions according to a wellbore operation. The filler discs 240 can be composed of or include aluminum or any other suitable material. The filler discs 240 can reduce the volume or empty space of the cavity of the simulated wellbore 215 (e.g., the free interior volume inside the wellbore cavity, also referred to herein as the free wellbore volume, FWBV). The more volume that is consumed by the filler discs 240, the greater the magnitude of the pressure reduction experienced (DUB effect) post-detonation of the explosive charge 135. The filler disc 240 can be any size, dimension, or thickness suitable for a given operation. For instance, as the filler discs 240 occupy an increasing proportion of the space of the cavity of the simulated wellbore 215, and therefore reduce FWBV relative to the FGV, a larger magnitude of DUB effect can be expected. However, to increase the magnitude of a DOB effect both the FWBV and FGV would be reduced, e.g., by occupying greater amount of the volumes in the cavity of the simulated wellbore 215 and the total interior volume in the interior cavity 125 of the perforating tool 100 with the filler discs 240 and plates 130, respectively. That is, while a reduction in the FWBV can increase the magnitude of the DUB and DOB effects, it is the value of the FGV can be the primary driver for which direction of pressure effect result, e.g., a DUB or DOB effect.
The face plate 220 can be disposed within the simulated wellbore 215 between the perforating tool 100 and the formation sample 220includes, for example, a simulated casing or cement. The face plate 220 can be composed of or include steel and can be backed by a cement layer. In some embodiments, the tool 100 and the formation sample 220 can couple directly or indirectly to the face plate 220. In some embodiments, the tool 100 can be disposed or positioned within or adjacent to the face plate 220, for example, the tool 10 can be seated in one or more grooves (not shown) of the face plate 220.
Based on the present disclosure, one skilled in the art would understand how the FGV could be adjusted, by adding or subtracting plates, or using different sized plates, in the interior cavity to achieve a target DUB or DOB pressure response when testing the explosive charge to evaluate explosive charge performance
For instance, prior to perforating the casing that lines a wellbore, the fluid in the wellbore may be isolated from the fluid (e.g., oil and gas) in the formation. Because of that isolation, the wellbore pressure can be set to some static pressure value relative to the pore pressure in the subterranean formation. A wellbore pressure set to be less than, greater than or the same as the pore pressure in the formation refer to a static underbalance, static overbalance and static on-balance pressure, respectively. After the explosive charge inside the perforating tool body is detonated, three different previously isolated volume zones can be nearly instantaneously hydraulically combined. The detonated explosive charge generates an explosive jet that punctures a hole in the perforation tool body and thereby hydraulically connects the FGV to the free interior volume inside the wellbore (e.g., the free wellbore volume, FWBV) and thereby hydraulically connects the FGV to the FWBV. The explosive jet also punctures though the casing and out into the subterranean formation and thereby hydraulically connects the FGV and the FWBV to the pore volume space of the formation. Thus during such a perforating operation the pressure of these three volumes zone are dynamically changing as they come to an equilibrium with each other. Whether a DUB or DOB pressure response is formed will depend upon at least the static pressure condition in the wellbore prior to the perforating operation and the FGV of the body.
As an example, consider a wellbore in an static overbalance pressure condition prior to perforating operation and the FGV is adjusted (by adjusting the number of plates 130 in the tool body 105 of the laboratory tool 100) such that when the FGV becomes hydraulically connected to the wellbore, the wellbore pressure drop to a value that is less than the pore pressure in the formation, resulting in a DUB pressure response. As another example, consider a wellbore in a static overbalance pressure condition prior to a perforating operation and the FGV is adjusted such that when the FGV becomes hydraulically connected to the wellbore, the wellbore pressure increases to a value that is greater than the pore pressure in the formation, resulting in a DOB pressure response. Based upon the present disclosure one skilled in the pertinent art would understand DUB and DOB pressure conditions could result when the wellbore is in a static underbalance, static on-balance or static overbalance pressure condition prior to perforating operation.
Aspects disclosed herein include a perforating tool. The tool can include a body, a first lid and a second lid. The first lid can be attachable to one end of the body and the second lid can be attachable to an opposite end of the body, to define an interior cavity of the body, the interior cavity having an air-tight seal with an exterior environment surrounding the body. The tool can include one or more plates disposable within the interior cavity such that the one or more plates are situated apart from an explosive charge when the explosive charge is disposed in the interior cavity. The one or more plates occupy part of a total interior volume of the interior cavity and thereby reduce a free interior volume inside the body.
In some such embodiments, the one or more plates in combination can occupy between 0 and 100 percent of the total interior volume of the interior cavity. In some such embodiments, individual ones of the plates can be sized such that any one of the plates occupy from greater than 0 to nearly 100 percent of the total interior volume. In some such embodiments, the plates can be composed of a non-deformable and impermeable material. In some such embodiments, a surface of one plate facing and nearest to the explosive charge can be shaped to form a depression that mirrors a shape of the explosive charge. In some such embodiments, at least two of the one or more plates can be shaped to stack together. In some such embodiments, the one or more plates are shaped to fit flush against an interior wall of the body. In some such embodiments, a surface of the second lid facing the interior cavity can include a port to secure a first end portion of a rod therein. A stem portion of the rods can be sized to pass through an opening in each of the one or more plates and a second end portion of the rod can include a stop structure sized to not pass through the opening in each of the one or more plates. In some such embodiments, each of the one or more plates can include an opening sized to allow a portion of a detonation cord there-though to connect to the explosive charge.
Aspects disclosed herein include another perforating tool. The tool can include a body, a first lid and a second lid. The first lid can be attachable to one end of the body and the second lid can be attachable to an opposite end of the body, to define an interior cavity of the body, the interior cavity having an air-tight seal with an exterior environment surrounding the body. The tool can include two or more plates disposable within the interior cavity such that the two or more plates are situated apart from an explosive charge when the explosive charge is disposed in the interior cavity. The two or more plates occupy part of a total interior volume of the interior cavity and thereby reduce a free interior volume inside the body.
In some such embodiments, a surface of one plate of the two or more plates that faces and is nearest to the explosive charge, touches the explosive charge. In some such embodiments, the surface of the one plate can be shaped to form a depression that mirrors a shape of the explosive charge. In some such embodiments, the two or more plates disposed within the interior cavity can be situated apart from the explosive charge. In some such embodiments, a surface of one plate of the two or more plates that faces and is nearest to the explosive charge can be shaped to form a depression that mirrors a shape of the explosive charge. In some such embodiments, the surface of the one plate of the two or more plates that faces and is nearest to the explosive charge can be a planar surface. In some such embodiments, the two or more plates in combination can occupy between 0 and 100 percent of the total interior volume of the interior cavity. In some such embodiments, individual ones of the plates can be sized such that any one of the plates occupy from greater than 0 to nearly 100 percent of the total interior volume. In some such embodiments, the plates can be composed of a non-deformable and impermeable material. In some such embodiments, a surface of one plate facing and nearest to the explosive charge can be shaped to form a depression that mirrors a shape of the explosive charge. In some such embodiments, at least two of the one or more plates can be shaped to stack together. In some such embodiments, a surface of the second lid facing the interior cavity can include a port to secure a first end portion of a rod therein. A stem portion of the rods can be sized to pass through an opening in each of the one or more plates and a second end portion of the rod can include a stop structure sized to not pass through the opening in each of the one or more plates. In some such embodiments, each of the two or more plates can include an opening sized to allow a portion of a detonation cord there-though to connect to the explosive charge.
Aspects disclosed herein perforating tool testing system. The system can include a simulated wellbore case; a simulated wellbore disposed within the simulated wellbore case; a face plate disposed at a first end of the simulated wellbore; a formation sample disposed within the simulated wellbore case, wherein the formation sample couples to the face plate; and a laboratory perforating tool disposed within the simulated wellbore between a second end and the first end of the simulated wellbore. The laboratory perforating tool can include any of the aspects of the laboratory perforating tools disclosed herein.
Further additions, deletions, substitutions and modifications may be made to the described embodiments.
