Apparatus and method for jet perforating and cutting tool

Abstract

A system and method for jet perforating within a well are disclosed. A jet perforating tool configured to be lowered inside a production tubing string comprises a tool body with a passage, an inlet in the upper section, perforating jets in the lower section, and a stepped outer diameter configured to seat on a production tubing string restriction such as a seat nipple. The tool may be lowered into the production tubing string without the need to trip the production tubing string in and out of the wellbore.

Claims

1. A jet perforating tool comprising: a tubular tool body having an upper section and a lower section; an inlet in the upper section, the inlet configured to accept jet cutting fluid from pressurized jet cutting fluid in a production tubing string surrounding the tubular tool body; a stepped outer diameter portion configured to rest on a restriction seat nipple within the production tubing string, wherein the stepped outer diameter comprises multiple steps configured with steps that fit a plurality of differently-sized seat nipples of different production tubing strings; at least one seat seal, wherein the at least one seat seal is positioned between the tubular body and the restriction seat nipple and configured to seal the tubular body to the seat nipple of the production tubing string under application of pressure from a pressurized fluid in the production tubing string; at least one hole in the lower section; a passage through at least part of the tool body connecting the inlet to the at least one hole; a jet affixed to at least one hole; and a retrieval rod configured to facilitate tool retrieval.

2. The jet perforating tool of claim 1, further comprising a nose piece.

3. The jet perforating tool of claim 2, wherein the nose piece is selected from the group consisting of a pressure tester, a circulation sub, and a wash tool.

4. The jet perforating tool of claim 3, further comprising a threaded connection fitting connecting the tool body to the nose piece.

5. The jet perforating tool of claim 1, wherein the seat seal is selected from the group consisting of plastic, rubber, compressed fiber, metal, polytetrafluoroethylene, graphite, vermiculite, cork, felt, neoprene, and fiberglass.

6. The jet perforating tool of claim 1, wherein the seat seal is an o-ring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:

(2) FIG. 1 shows a schematic side view of a jet perforating tool, according to one embodiment;

(3) FIG. 2 shows a schematic side view of an embodiment of the jet perforating tool with a nose;

(4) FIG. 3 shows a flowchart illustrating an example embodiment of a method for performing perforating or cutting jobs in a well;

(5) FIG. 4 shows a schematic side view of an alternative embodiment of the jet perforating tool;

(6) FIGS. 5A and 5B show schematic side views of embodiments of the jet perforating tool having a pressure tester;

(7) FIGS. 6A and 6B show schematic side views of embodiments of the jet perforating tool having a circulation sub;

(8) FIGS. 7A, 7B, and 7C show schematic side views of embodiments of the jet perforating tool having wash tool; and

(9) FIGS. 8A and 8B show flowcharts illustrating an example embodiment of a method for performing well jobs.

DETAILED DESCRIPTION

(10) A wireline-conveyed jet perforating tool allows the jet perforating tool to be lowered and raised through a production tubing string, with the tool sealed in a seat or restriction already located in the string, to allow the fluid to be pumped to the tool. The tool can then be used for perforating or cutting casing or tubing. Operation of the wireline-conveyed jet perforating tool provides faster performance of abrasive jet perforating or cutting in wells. An apparatus for performing jet perforating and cutting may include a stepped outer diameter. The tool may circulate, wash, and pressure test. The jet perforating and cutting may be performed with abrasive fluid.

(11) FIG. 1 shows a schematic side view of a jet perforating tool in a wellbore according to one embodiment. A jet perforating tool 10 is shown suspended in a wellbore 11 that is penetrating a reservoir 12. The wellbore 11 is surrounded by a casing 13, which in turn is surrounded by cement 14, fixing the casing 13 to the reservoir 12. A production tubing string 15 extends vertically downward into the wellbore 11. The jet perforating tool 10 sits in a restriction (seat) 17 at the lower end of the production tubing string 15. In one embodiment, the restriction 17 is a seating nipple. Jet perforating tool 10 may be placed in the production tubing string in a number of ways. According to one embodiment, jet perforating tool 10 is lowered by wireline (not shown), which extends down through the production tubing string 15. When the wireline remains in place during perforating, the wireline may exit the top of the wellbore 11 through a lubricator or pack-off (not shown). The jet perforating tool 10 may be suspended from the wireline, or the wireline may be retracted, leaving jet perforating tool 10 seated in restriction 17. According to another embodiment, jet perforating tool 10 may be dropped into the production string 15. In yet another embodiment, jet perforating tool 10 may be pumped into the production string 15, such as in highly deviated wells.

(12) FIG. 2 illustrates one embodiment of a jet perforating tool with a nose. Jet perforating tool 10 includes retrieval rod 35, fluid inlet 50, seat no-go 51, seat seals 52, jets 39, and threaded connection 36. Depending on the specific application, the general embodiment may use one or more variations to this basic configuration. Retrieval rod 35 may be affixed to the wireline during lowering or raising of jet perforating tool 10. In the alternative, wireline or another extraction means may be affixed to retrieval rod 35 within the wellbore, such as with an oilfield fishing apparatus (not shown) like the Logan Oil Tools Series 20 Sucker Rod Overshot. Although not discussed, other tool capturing devices may be used to secure the jet perforating tool and remove it from the tubing string. For example, one capturing tool may include a fishing neck on the top of the tool and a latch-type retrieval tool that would lock onto it for retrieval. Another example of a capturing tool may include a grapple, which is part of a larger class of fishing tools called overshots, designed to fit over a tool in the hole and grab onto it for retrieval. One example of such a grapple is the Weatherford Heavy Duty GS.

(13) Stepped outer diameter 51, which may be a seat no-go, is configured to rest on restriction 17. The weight of jet perforating tool 10 or the fluid pressure of the pumped fluid holds seat no-go 51 against seat nipple 17. In addition to the stepped outer diameter other configurations may be used. For example, the stepped outer diameter may be specifically shaped to mate with the type of restriction or fitting present in the tubing. According to another embodiment, jet perforating tool 10 may have a gradual increase in outer diameter towards the upper section of the tool. When operating under high pressure, a gradual outer diameter increase can cause the jet perforating tool to become stuck in the production tubing string. The stepped outer diameter 51 may reduce the likelihood of the tool becoming stuck. To account for multiple restriction designs, stepped outer diameter 51 may include multiple steps, thereby allowing one jet perforating tool to properly seat on different sized production tubing restrictions.

(14) The stepped outer diameter 51 holds jet perforating tool 10 in place against seat nipple 17. Additional seat seals 52 may improve sealing of the seat seals 52 against the inner diameter of seat nipple 17. In one embodiment, seat seals 52 are rings of a moderately malleable material, such as plastic or rubber. Seat seals 52 may slide onto jet perforating tool 10 and rest within a notched outer diameter such as a mandrel (not shown). Seat seals 52 may comprise other materials known in the art of tool sealing, such as compressed fiber, metal, rubber, polytetrafluoroethylene, graphite, vermiculite, cork, felt, neoprene, fiberglass, or any other material known in the art of gasket or sealing ring design. In one embodiment, seat seals 52 may take the form of plastic polymer o-rings affixed to perforating jet tool 10 within a mandrel. Seat seals 52 may also take alternate forms such as sealing jackets, inflatable compression balloons, or other sealing devices. Other sealing devices may include seals, packer, or plug-type seals. A packer may be inflatable, and a plug may include a rubber material, which may be compressed to make it expand and seal. According to another embodiment, seat no-go 51 may contain seat seal 52 on the underside of the no-go 51. In this embodiment, the compression seat seal 52 between no-go 51 and seat nipple 17 may prevent leakage of abrasive jet fluid or any alternative fluid within the system. In another embodiment, seat seal 52 may be located on the outer side of seat no-go 51 or on the side of upper portion 25 of the tool body, below inlet 50.

(15) The jet perforating tool 10 may include jets 39, such as abrasive jets. The jets 39 eject jet cutting fluid such as abrasive-carrying slurry under high pressure to perforate the casing 13, cement 14, and reservoir 12. The jets 39 may perforate a cavity into the reservoir 12 through the cement 14 and casing 13 with the wellbore 11. This cavity may provide improved fluid flow from the reservoir 12 to the wellbore 11, preferably from a zone in the reservoir 12 producing oil or gas. In an alternative situation called an openhole wellbore, there is no casing 13 or cement 14, so the wellbore 11 may directly contact the reservoir 12. In an alternative use, the jet perforating tool 10 is used to cut (sever) the casing 13, cement 14, or production tubing string 15.

(16) This use of the jet perforating tool 10 as a perforating tool is further described in U.S. Pat. No. 7,963,332, “Apparatus and Method for Abrasive Jet Perforating,” issued Jun. 21, 2011, which is incorporated by reference. This use of the jet perforating tool 10 as a cutting tool is further described in co-pending U.S. patent application Ser. No. 12/653,803, “Apparatus and Method for Abrasive Jet Perforating and Cutting of Tubular Members,” filed Dec. 18, 2009, which is incorporated by reference.

(17) FIG. 4 shows a schematic side view of the abrasive jet perforating tool according to one embodiment. The jet perforating tool 10 may include a main tool body 21 and the nose piece 18. The main tool body 21 of the jet perforating tool 10 may include a conduit, such as in the form of a cylindrically-shaped tube with a passage 22 extending at least a portion of the length of the tool body 21, or the entire length as seen in FIG. 4. The passage 22 has an inner diameter 23 and the tool body 21 has an outer diameter 24. Although the jet perforating tool 10 is illustrated here with the tool body 21 as a tube, the tool body 21 may take shape other than a cylindrical shape.

(18) The tool body 21 may include an upper section 25 and a lower section 30 with a side 31. Both sections 25 and 30 are connected together with the passage 22 extending throughout at least a portion of the sections 25 and 30. According to one embodiment, the nose piece 18 has a threaded connection fitting 36 located at the upper end of the nose piece 18 and may be affixed to tool body 21 by way of the threaded connection fitting 36. In one embodiment, the passage 22 may not extend through the nose piece 18.

(19) The lower section 30 of tool body 21 may include a threaded connection fitting 36. Nose piece 18 contains a connection fitting configured to mate to threaded connection fitting 36. Passage 22 may extend through threaded connection fittings 36 into nose piece 18. In one embodiment, the nose piece 18 may be solid and rounded on the bottom end to act as a guide through the production well tubing string 15 and to add weight to the jet perforating tool 10. The upper end of tool body 21 is coupled to retrieval rod mechanism 35. Additional weight or ballast may be placed within upper section 25 of jet perforating tool 10.

(20) Located below seat seals 52 is lower section 30. Lower section 30 contains at least one hole 37 in the side 31 of jet perforating tool 10. In one embodiment, jet perforating tool 10 will have a plurality of the holes 37 in multiple locations of lower section 30. As illustrated in FIG. 4, the holes 37 are oriented in a direction that is perpendicular, or near perpendicular, to the longitudinal axis of the tool body 21. Jets 39 are mounted in the holes 37 in the side 31 of the lower section 30.

(21) In one embodiment, the holes 37 are threaded holes tapped into the side 31 of the lower section 30. In this embodiment, the jets 39 comprise threaded jets mounted in at least some of the threaded holes 37 in the side 31 of the lower section 30. The jets may be protected from the splash back of abrasive-carrying fluid slurry ejected by the jets 39 by protective plates (not shown) mounted on the side 31 of the lower section 30 around the jets 39. This use of threaded jets 39 is described in one example in U.S. Pat. No. 7,963,332, “Apparatus and Method for Abrasive Jet Perforating,” issued Jun. 21, 2011, which is incorporated by reference.

(22) In another embodiment, the holes 37 are smooth holes drilled into the side 31 of the lower section 30. In this embodiment, the jets 39 comprise smooth jets mounted in at least some of the smooth holes 37 in the side 31 of the lower section 30. In this embodiment, the jets 39 are held in place by protective plates (not shown) mounted around the jets 39 and secured by fasteners (not shown), such as screws, to the side 31 of the lower section 30. The fasteners are positioned away from the splash back of abrasive-carrying fluid slurry ejected by the jets 39. This use of smooth jets 39 is described in co-pending U.S. patent application Ser. No. 13/507,971, “Apparatus and Method for Abrasive Jet Perforating,” filed Aug. 9, 2012, which is incorporated by reference.

(23) FIG. 4 further illustrates an exemplary embodiment according to aspects of the present disclosure. Jet perforating tool 10 includes at least one inlet 50 located in a section of the jet perforating tool 10 above seat seals 52. Inlet 50 connects to passage 22. According to one embodiment, abrasive slurry pumped into the resident tubing string (not shown) enters inlet 50 and exits jets 39. Jet perforating tool 10 may have one or more inlets 50.

(24) A method for performing abrasive jet perforating cutting may use the jet perforating tool described above. FIG. 3 is a flowchart illustrating a method for performing perforating or cutting jobs in a well. The following is one method by which the perforating or cutting will be performed on a well with the production tubing string, the pump rods, and a pump still present in the casing. By way of example, the following method is disclosed according to use of jet perforating tool 10.

(25) At block 40, pump rods and pump are removed from the well. Any other items that may be inside the production tubing string may also be removed. At block 41, the production tubing string is raised or lowered to the desired perforating or cutting depth in the well, if necessary. At block 42, jet perforating tool 10 is run into the production tubing string. This may be performed using a wireline until it comes to rest and seats on the restriction 17, such as a seating nipple. In the alternative, jet perforating tool 10 may be dropped into the tubing string or pumped into the tubing string until the tool 10 comes to rest and seats on restriction 17. This process of installing the jet perforating tool 10 inside the tubing string may take minutes to perform, much shorter than the hours it typically would take to use the production tubing string to lower the tool.

(26) Prior to lowering the tool at block 42, parameters may be determined for a well to be perforated or cut. These well parameters may include, but are not limited to, the type and thickness of casing, the type and thickness of cement, the type of reservoir rock to be encountered in the zones to be perforated, and the depth of the zones to be perforated or tubing to be cut. These parameters may be used when assembling the appropriate components of a jet perforating tool. The assembly of the tool can take place onsite or offsite. If the tool is assembled offsite, then the tool may be shipped to the well site, where the tool assembly can be easily changed if the well parameters have changed or turn out to be different than originally expected.

(27) At block 43, a perforating job is performed by pumping abrasive fluid slurry through the production tubing string and the jet perforating tool. The jet perforating tool could also be used for cutting by rotating the tubing from the surface. The jet perforating tool can also be used to slot, either vertically or horizontally by manipulating the tubing from the surface with a workover unit. In configurations where the wireline stays attached to the jet perforating tool, the wireline exits the tubing at the surface through a lubricator.

(28) The production tubing string may be flushed with clear fluid, such as without abrasives, as shown at block 44, until the production tubing string and the jet perforating tool are flushed and sand is returned to surface. Jet perforating tool 10 may be returned to the surface without first flushing the apparatus with clear fluid.

(29) At block 45, the jet perforating tool is run out of the well using the wireline. This process of removing the jet perforating tool using a wireline typically takes minutes to perform, much shorter than the hours it typically would take to use the production tubing string to remove the tool. Depending on the method used to deploy jet perforating tool 10, block 45 may include the additional step of connecting a wireline or other extraction means to jet perforating tool 10 by use of an oilfield fishing apparatus (not shown) like the Logan Oil Tools Series 20 Sucker Rod Overshot.

(30) After the jet perforating tool is removed, the production tubing string is returned to a desired depth at block 46, and, at block 47, the pump and pump rod are run back into the well.

(31) The jet perforating and cutting method and apparatus described here has numerous advantages. In particular, the tool greatly reduces the number of runs for bringing a production tubing string in and out of the well. Time, as well as cost, is saved from the reduced work for the workover equipment. Furthermore, a secondary system such as coiled tubing is not required. These savings can be seen in the following comparison.

(32) Existing methods of jet perforating lower the jet perforating tool on a tubing string, requiring the production tubing string to be removed and then reinserted. In addition, the jet perforation tool is lowered and removed on a tubing string as well. This conventional method requires the workover unit to either trip in or trip out the production tubing string four times. On a well that is 5,000 feet deep, this conventional process would take at least 2 hours for each trip. By contrast, the method as disclosed is now much shorter. In particular, moving the production string to a new depth would only take minutes compared with the hours required to run the production tubing string into and out of the well. Similarly, running the jet perforating tool into or out of a well with a wireline would take only minutes compared with the hours required to run the production tubing string into and out of the well.

(33) Depending on the specific application, alternative embodiments of the abrasive jet perforating tool 10 may use one or more variations to the general embodiment illustrated in FIG. 2. Some of these possible alternative embodiments are illustrated in FIGS. 5-7.

(34) FIGS. 5A and 5B show schematic side views of other alternative embodiments of the tool configured as a pressure tester. In some embodiments, the tool body 21 has no ports in the side 31 of the lower section 30. In the embodiment illustrated in FIG. 5A, the tool body 21 may have no holes 37 in the side 31 of the lower section 30 and have no jets. In another embodiment illustrated in FIG. 5B, the tool body 21 has all the jets 39 that are mounted in the holes 37 in the side 31 of the lower section 30 but with plugs 52 inserted. These embodiments of the tool body 21 allow the jet perforating tool 10 to be used as a pressure tester. Pressure testing may be used to ensure tubing integrity of the production tubing string 15.

(35) FIGS. 6A and 6B show schematic side views of other alternative embodiments of the jet perforating tool configured as a circulation sub. In these embodiments, the nose piece may be replaced by a circulation sub 61. The circulation sub 61 may include a passage 62 extending throughout and connecting to the passage 22 through the tool body 21.

(36) In one embodiment illustrated in FIG. 6A, the circulation sub 61 has a forward-facing flow exit path 63. In another embodiment illustrated in FIG. 6B, the circulation sub 61 has a plurality of forward-angled flow exit paths 64 to facilitate fluid circulation to clean out the well. In either embodiment, the tool body 21 may have no holes in the side 31 of the lower section 30 and no jets, as illustrated in FIG. 6A, or the tool body 21 could have all the jets that are mounted in the holes 37 in the side 31 of the lower section 30 with plugs 52 inserted, as illustrated in FIG. 6B.

(37) FIGS. 7A, 7B, and 7C show schematic side views of other embodiments of the jet perforating tool configured as a wash tool. In these embodiments, the nose piece may be replaced by a wash tip 71. The wash tip 71 may have a passage 72 extending throughout. The wash tip 71 may also include a plurality of forward-angled jets 73 acting as flow exit paths to circulate fluid and clean out the well.

(38) In one embodiment illustrated in FIG. 7A, the lower section 30 of the tool body 21 has the jets 39 in the holes 37 in the side 31 acting as side jets to assist the plurality of forward-angled jets 73 in the wash tip 71. In another embodiment illustrated in FIG. 7B, the lower section 30 of the tool body 21 has plugs 52 inserted in the jets 39 to force additional fluid through the plurality of forward-angled jets 73 in the wash tip 71. In another embodiment illustrated in FIG. 7C, the lower section 30 of the tool body 21 has no jets to force additional fluid through the plurality of forward-angled jets 73 in the wash tip 71.

(39) A variety of different jet quantities, orifice sizes, and placement locations can be used with the embodiments illustrated above in reference to FIGS. 1-2 and 4-7 for this tool. Additionally, different materials could be used in the making of the various apparatuses described.

(40) FIGS. 8A and 8B show flowcharts illustrating an example embodiment of a method for performing well jobs using some of the additional embodiments shown in FIGS. 4-7.

(41) At block 80 in FIG. 8A, pump rods and pump are run out of the well. Any other items that may be inside the production tubing string are also removed.

(42) At block 81, the production tubing string is moved to the desired perforating or cutting depth in the well. The production tubing string may be raised or lowered as necessary.

(43) At block 82, a pressure testing tool is run into the production tubing string until the tool comes to rest and seats on the restriction, which may be a seating nipple, at the bottom end of the production tubing string. This may be accomplished via wireline, or by dropping or pumping the tool down the tubing string. The pressure testing tool can be either the no-jet tool shown in FIG. 5A or the jet perforating tool with plugs in all the abrasive jet locations shown in FIG. 5B.

(44) At block 83, the production tubing string is pressurized to check for leaks.

(45) At block 84, the pressure testing tool is run out of the well.

(46) At block 85, a jet perforating tool is run into the production tubing string until it comes to rest and seats on the restriction located within the production tubing string. This may be accomplished in one embodiment by lowering the jet perforating tool on a wireline. In the alternative, the jet perforating tool may be dropped into the production tubing string. In yet another embodiment, the jet perforating tool may be pumped down the well until it comes to rest on the restriction.

(47) At block 86, a perforating or cutting job is performed by pumping abrasive fluid slurry through the production tubing string and the jet perforating tool. In one embodiment, the wireline may stay attached to the jet perforating tool and the abrasive fluid may exit the tubing at the surface through a lubricator. The process then proceeds to block 87 in FIG. 8B.

(48) The production tubing string may be flushed with clear fluid, such as with no abrasives, as shown in block 87, until the production tubing string and the jet perforating tool are flushed and sand is returned to surface. The jet perforating tool may also be returned to the surface without first flushing the apparatus with clear fluid.

(49) At block 88, the jet perforating tool is run out of the well using the wireline.

(50) At block 89, the wash tool or circulation sub tool is run into the production tubing string using a wireline until it comes to rest and seats on the restriction at the bottom end of the production tubing string.

(51) At block 90, a desired circulation job is performed to clean the well.

(52) At block 91, a wash tool or circulation sub tool is run out of the production tubing string.

(53) At block 92, the production tubing string is moved to a desired depth. The production tubing string may be raised or lowered, as necessary.

(54) At block 93, the pump rods and pump are run back into the well.

(55) Lowering and removing the tools with the wireline, as described in certain embodiments in FIGS. 8A and 8B, is a process that takes only a few minutes as opposed to running the production tubing string into and out of the well, which takes hours.

(56) Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.