US20220220821A1 - Wiper plug - Google Patents
Wiper plug Download PDFInfo
- Publication number
- US20220220821A1 US20220220821A1 US17/145,137 US202117145137A US2022220821A1 US 20220220821 A1 US20220220821 A1 US 20220220821A1 US 202117145137 A US202117145137 A US 202117145137A US 2022220821 A1 US2022220821 A1 US 2022220821A1
- Authority
- US
- United States
- Prior art keywords
- ring
- wiper plug
- seal unit
- mandrel
- extrusion assembly
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000001125 extrusion Methods 0.000 claims abstract description 83
- 230000007704 transition Effects 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims description 5
- 230000004044 response Effects 0.000 claims description 2
- 239000012530 fluid Substances 0.000 description 27
- 239000004568 cement Substances 0.000 description 14
- 238000007789 sealing Methods 0.000 description 14
- 238000006073 displacement reaction Methods 0.000 description 11
- 239000000463 material Substances 0.000 description 11
- 239000002002 slurry Substances 0.000 description 9
- 230000001154 acute effect Effects 0.000 description 8
- 230000036316 preload Effects 0.000 description 8
- 238000005086 pumping Methods 0.000 description 8
- 238000004891 communication Methods 0.000 description 6
- 238000005553 drilling Methods 0.000 description 6
- 229920001971 elastomer Polymers 0.000 description 4
- 239000000806 elastomer Substances 0.000 description 4
- 230000003993 interaction Effects 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 230000005484 gravity Effects 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 239000011152 fibreglass Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 241000282472 Canis lupus familiaris Species 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 230000001010 compromised effect Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229920000747 poly(lactic acid) Polymers 0.000 description 1
- 239000004626 polylactic acid Substances 0.000 description 1
- -1 polytetrafluoroethylene Polymers 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000012858 resilient material Substances 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
- E21B33/14—Methods or devices for cementing, for plugging holes, crevices or the like for cementing casings into boreholes
- E21B33/16—Methods or devices for cementing, for plugging holes, crevices or the like for cementing casings into boreholes using plugs for isolating cement charge; Plugs therefor
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/02—Surface sealing or packing
- E21B33/08—Wipers; Oil savers
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/12—Packers; Plugs
- E21B33/1208—Packers; Plugs characterised by the construction of the sealing or packing means
- E21B33/1216—Anti-extrusion means, e.g. means to prevent cold flow of rubber packing
Definitions
- Embodiments of the present disclosure generally relate to plugs that are used during the cementing of liners, such as those used in oil, gas, and water wells.
- a wellbore is formed by using a drill bit on a drill string to drill through a geological formation.
- a drilling fluid known as mud
- mud is circulated to lubricate the drill bit, remove rock cuttings from the wellbore, and provide a hydrostatic pressure to counteract the in situ pressure of the geological formation.
- the drill string and drill bit are removed, and the wellbore is lined by inserting a string of casing into the wellbore. At least a portion of the annulus between the inner surface of the wellbore and casing is filled with cement using a cementing operation.
- a cementing operation involves the pumping of a cement slurry through the casing, out of the bottom of the casing, and up the annulus.
- a casing string is hung off from a wellhead located at the top of the wellbore.
- An equivalent string of tubulars that is hung off from a location within the wellbore below the wellhead is typically referred to as a liner.
- a liner is deployed to a desired depth in the wellbore using a workstring, and suspended from a previously-installed casing by using a liner hanger.
- a setting tool is then operated to set a liner hanger against the previously installed casing.
- the liner hanger may include slips riding outwardly on cones in order to engage the surrounding casing.
- the setting tool is typically operated by pumping a ball through the workstring to a seat located below the setting tool. Pressure is exerted on the seated ball to operate the setting tool.
- the liner hanger is cemented in place by pumping a cement slurry down the workstring, into the liner, out of the bottom of the liner, and into the annulus between the liner and the inner surface of the wellbore.
- Wiper plugs are used to segregate the cement slurry from the drilling fluid while the cement slurry travels down the casing or liner.
- darts may be used to segregate the cement slurry from other fluids while the cement slurry travels down the workstring.
- Each dart picks up a corresponding wiper plug that is installed in an upper portion of the liner below the liner hanger to ensure the fluids remain segregated while the cement travels down through the liner.
- dart and a corresponding wiper plug operate to segregate the cement from fluid, such as drilling fluid, that is pumped after the cement to move the cement out of the bottom of the liner and into the annulus between the liner and the inner surface of the wellbore.
- a wiper plug typically has an elastomeric body mounted on a mandrel and elastomeric external fins that bear against the inner wall of the casing.
- the fins wipe mud solids and other accumulated debris off the inner wall of the casing.
- the effectiveness of a wiper plug relies on at least one fin creating a seal against the surrounding casing or liner, and the body sealing against the mandrel.
- the elastomer material usually has a hardness that provides for structural robustness, such as for wiping of the casing or liner, and resistance to abrasion, yet is sufficiently malleable to be deformed so as to provide the necessary seals.
- the hardness decreases with increasing temperature, and thus at elevated temperatures within wellbores, the elastomeric body and the fins become susceptible to extrusion, which compromises their sealing capability.
- the present disclosure generally relates to a wiper plug for use in a wellbore or other conduit, such as a pipeline.
- a wiper plug in one embodiment, includes a mandrel having a nose portion at a leading end thereof.
- a seal unit including a body and one or more fins extending outwardly from the body, is disposed about the mandrel.
- An anti-extrusion assembly is disposed about the mandrel at a leading end of the seal unit. The anti-extrusion assembly is arranged to transition between a first configuration, in which the anti-extrusion assembly is not energized, and a second configuration, in which the anti-extrusion assembly is energized.
- the nose portion protrudes beyond the anti-extrusion assembly.
- a wiper plug in another embodiment, includes a mandrel and a seal unit disposed about the mandrel, the seal unit having a body and one or more fins extending outwardly from the body.
- An anti-extrusion assembly is disposed about the mandrel at a leading end of the seal unit. The anti-extrusion assembly is arranged to transition between a first configuration, in which the anti-extrusion assembly is not energized, and a second configuration, in which the anti-extrusion assembly is energized, in response to a pressure applied to an obturating object landed in the wiper plug.
- a wiper plug in another embodiment, includes a mandrel and a seal unit disposed around the mandrel.
- the seal unit includes a body having an inner surface, a leading end, and a trailing end, and one or more fins extending outwardly from the body.
- the inner surface includes a first, generally cylindrical, portion and a second portion.
- the second portion includes an inwardly extending shoulder located between the first portion and the leading end and facing toward the trailing end.
- the shoulder is substantially perpendicular to a longitudinal axis of the mandrel.
- the second portion further includes a first taper between the shoulder and the leading end.
- the seal unit body has a first inner diameter at a first location on the first taper proximal to the leading end and a second inner diameter at a second location on the first taper distal from the leading end. The first inner diameter is greater than the second inner diameter.
- a method in another embodiment, includes suspending a wiper plug from a support disposed in a tubular, and energizing an anti-extrusion assembly of the wiper plug while the wiper plug remains suspended from the support.
- FIG. 1 is a longitudinal cross-sectional view of a wiper plug.
- FIG. 2 is a longitudinal cross-sectional view of the wiper plug of FIG. 1 , but with some components omitted.
- FIG. 3 is a longitudinal cross-sectional view of a component of the wiper plug of FIG. 1 .
- FIG. 4 is a longitudinal cross-sectional view of some components of the wiper plug of FIG. 1 .
- FIG. 5A is a longitudinal cross-sectional view of the wiper plug of FIG. 1 during an exemplary phase of operation.
- FIG. 5B is a longitudinal cross-sectional view of an embodiment of the wiper plug of FIG. 1 during the exemplary phase of operation of FIG. 5A .
- FIG. 6A is a longitudinal cross-sectional view of the wiper plug of FIG. 1 during an exemplary phase of operation.
- FIG. 6B is a longitudinal cross-sectional view of an embodiment of the wiper plug of FIG. 1 during the exemplary phase of operation of FIG. 6A .
- FIG. 7A is a longitudinal cross-sectional view of the wiper plug of FIG. 1 during an exemplary phase of operation.
- FIG. 7B is a longitudinal cross-sectional view of an embodiment of the wiper plug of FIG. 1 during the exemplary phase of operation of FIG. 7A .
- FIG. 8A is a longitudinal cross-sectional view of the wiper plug of FIG. 1 during an exemplary phase of operation.
- FIG. 8B is a longitudinal cross-sectional view of an embodiment of the wiper plug of FIG. 1 during the exemplary phase of operation of FIG. 8A .
- FIG. 9 is a longitudinal cross-sectional view of the wiper plug of FIG. 1 during an exemplary phase of operation.
- the present disclosure concerns wiper plug designs in which extrusion of a resilient component is inhibited. During use, a tendency of a resilient component of a wiper plug to deform detrimentally with a consequential loss of sealing integrity is thereby mitigated. Wiper plugs of the present disclosure provide robust wiping of the inner surface of a casing or liner, and sealing against the casing or liner that is effective at elevated temperatures that exist in a wellbore.
- FIG. 1 is a longitudinal cross-sectional view of a wiper plug 100 .
- FIG. 2 is a longitudinal cross-sectional view of the wiper plug 100 of FIG. 1 , but with some components omitted for clarity.
- the wiper plug 100 has a longitudinal axis 102 , a leading end 104 , and a trailing end 106 .
- the leading end 104 and trailing end 106 define opposite ends of the wiper plug 100 along the longitudinal axis 102 according to a direction of travel ( 418 , FIGS. 8A, 8B ) through a tubular for which the wiper plug 100 is configured.
- the wiper plug 100 has a mandrel 110 that, as illustrated, includes a lower mandrel segment 112 , a center mandrel segment 160 , and an upper mandrel segment 170 .
- the mandrel 110 may include greater than three segments.
- the mandrel 110 may include fewer than three segments.
- the mandrel 110 may be configured as a single component.
- the leading end 104 of the wiper plug 100 is also the leading end of the mandrel 110
- the trailing end 106 of the wiper plug 100 is also the trailing end of the mandrel 110 .
- the lower mandrel segment 112 has a longitudinal bore 114 therethrough.
- An outer surface 116 of the lower mandrel segment 112 includes a first portion 117 that is generally cylindrical and substantially aligned with the longitudinal axis 102 .
- the outer surface 116 also includes a slope 118 describing a generally frustoconical profile extending at an acute angle 118 a to the longitudinal axis 102 .
- a first outer diameter of the lower mandrel segment 112 at a first end 118 b of the slope 118 proximal to the leading end 104 is greater than a second outer diameter of the lower mandrel segment 112 at a second end 118 c of the slope 118 distal from the leading end 104 .
- the outer surface 116 of the lower mandrel segment 112 includes a second portion 152 that is generally cylindrical and substantially aligned with the longitudinal axis 102 .
- the slope 118 is located between the first 117 and second 152 generally cylindrical portions.
- the outer surface 116 of the lower mandrel segment 112 includes a ridge 154 .
- the second generally cylindrical portion 152 is located between the ridge 154 and the slope 118 .
- the lower mandrel segment 112 includes a nose portion 120 located at the leading end 104 .
- the nose portion 120 has a bore 122 with a diameter that is greater than a diameter of the bore 114 of the lower mandrel segment 112 at a location distal from the leading end 104 .
- the nose portion 120 may have a bore 122 diameter that is less than or equal to the diameter of the bore 114 of the lower mandrel segment 112 at a location distal from the leading end 104 .
- the nose portion 120 includes one or more seals 124 (two are illustrated) on an outer surface.
- the nose portion 120 includes a lock ring 126 on the outer surface. In some embodiments, it is envisaged that the one or more seals 124 and/or the lock ring 126 may be omitted.
- the lower mandrel segment 112 includes a lower seat assembly 130 .
- the lower seat assembly 130 includes a catcher 132 that extends into the bore 122 of the nose portion 120 .
- the catcher 132 is generally tubular, having an end port 134 and one or more side ports 138 .
- the catcher 132 includes a ledge 136 around the end port 134 .
- a lower seat sleeve 140 is at least partially disposed in the catcher 132 , and has a profile 142 configured to interact with an obturating object, such as a dart or a ball.
- the lower seat sleeve 140 is held in place by a releasable fastener 144 , such as a shear ring, shear pin, collet, latch, or the like. In some embodiments, it is contemplated that the lower seat assembly 130 may be omitted.
- the center mandrel segment 160 is coupled to the lower mandrel segment 112 , and has an outer surface 162 including a portion 163 that is generally cylindrical and substantially aligned with the longitudinal axis 102 .
- the center mandrel segment 160 also has a bore 164 that includes a taper 166 from a first bore diameter at a first location 166 a distal from the lower mandrel segment 112 to a second smaller diameter at a second location 166 b proximal to the lower mandrel segment 112 .
- the center mandrel segment 160 is coupled to the upper mandrel segment 170 .
- the upper mandrel segment 170 includes one or more retainers 172 , such as locking dogs, collets, latches, and the like.
- each retainer 172 is disposed in a corresponding opening 174 in the upper mandrel segment 170 .
- the one or more retainers 172 secure the wiper plug 100 to a support ( 410 , shown in FIG. 5A ) for deployment.
- An upper seat sleeve 180 having a profile 182 is at least partially disposed in the upper mandrel segment 170 and at least partially disposed in the center mandrel segment 160 .
- the profile 182 is configured to interact with an obturating object, such as a dart or a ball.
- the upper seat sleeve 180 extends across each opening 174 in the connector, and therefore maintains each retainer 172 in a radially extended position.
- the upper seat sleeve 180 is held in place by a releasable fastener 184 , such as a shear ring, shear pin, collet, latch, or the like.
- An o-ring 186 provides a seal between the upper seat sleeve 180 and the center mandrel segment 160 .
- a lock ring 188 in the center mandrel segment 160 is configured to engage a recess 192 in the upper seat sleeve 180 , as described below.
- the upper seat sleeve 180 has an external taper 194 such that an outer diameter of the upper seat sleeve 180 at a location distal from a lower end 196 of the upper seat sleeve 180 is greater than an outer diameter of the upper seat sleeve 180 at a location proximal to the lower end 196 of the upper seat sleeve 180 .
- the mandrel 110 is made of a material that provides structural rigidity, such as a metal, a plastic, or a composite material, such as fiberglass.
- the mandrel 110 may be made of a material that may be readily disintegrated upon being drilled through by a standard oilfield drill bit or mill.
- material may include aluminum.
- the mandrel 110 may be made of a material that may be readily dissolved by a suitable solvent.
- the material may include polylactic acid, and the solvent may include water.
- a seal unit 200 is disposed around the mandrel 110 .
- the seal unit 200 is illustrated in FIG. 3 .
- the seal unit 200 has a longitudinal axis 202 .
- the longitudinal axis 202 of the seal unit 200 is substantially coincident with the longitudinal axis 102 of the wiper plug 100 .
- the longitudinal axis 202 of the seal unit 200 may intersect the longitudinal axis 102 of the wiper plug 100 at an angle of from zero degrees to two degrees.
- the seal unit 200 has a leading end 204 consistent with the leading end 104 of the wiper plug 100 , and a trailing end 206 consistent with the trailing end 106 of the wiper plug 100 .
- the seal unit 200 has a body 210 from which a plurality of fins project outwardly. As illustrated, the seal unit 200 has a leading fin 212 located proximate to the leading end 204 , a trailing fin 218 located proximate to the trailing end 206 , and two intermediate fins 214 , 216 located between the leading fin 212 and the trailing fin 218 . As illustrated, the leading fin 212 is configured to perform both a sealing function against a surrounding surface and a wiping function of the surrounding surface when in operation. As illustrated, one intermediate fin 214 is configured to perform primarily a wiping function of a surrounding surface and secondarily a sealing function against the surrounding surface when in operation.
- the trailing fin 218 and one intermediate fin 216 are configured to perform primarily a sealing function against a surrounding surface and secondarily a wiping function of the surrounding surface when in operation.
- the body 210 and the fins 212 , 214 , 216 , 218 form a unitary structure of the seal unit 200 .
- the seal unit 200 may include individual segments. For example, each segment may include a body portion and a fin.
- the seal unit 200 is made of a resilient material, such as an elastomer, that provides resistance to deformation, yet is sufficiently flexible to yield elastically when under load. It is contemplated that the elastomer may have properties tailored for different parts or sections of the seal unit 200 . For example, one or more fins 212 / 214 / 216 / 218 may include an elastomer possessing a greater stiffness than one or more other fins 212 / 214 / 216 / 218 and/or the body 210 . In some embodiments, it is contemplated that the seal unit 200 may not include additional materials. However, in some embodiments, it is contemplated that the seal unit 200 may include additional materials.
- the seal unit 200 may include one or more support members in the body 210 and/or in one or more fins 212 / 214 / 216 / 218 .
- the one or more support members may provide enhanced stiffness to one or more sections of the seal unit 200 .
- the one or more support members may be made of metal, such as aluminum, or a composite, such as fiberglass.
- the seal unit 200 may have any suitable number of fins, such as one fin, two fins, three fins, four fins, five fins, six fins, seven fins, or more than seven fins. Additionally, it is contemplated that any suitable number of the fins of the seal unit 200 (such as no fins, one fin, two fins, three fins, or more than three fins) may be configured to perform primarily a wiping function of a surrounding surface and secondarily a sealing function against the surrounding surface when in operation.
- any suitable number of the fins of the seal unit 200 may be configured to primarily a sealing function against a surrounding surface and secondarily a wiping function of the surrounding surface when in operation.
- the body 210 has an inner surface 220 that includes a portion 222 extending from the trailing end 206 toward the leading end 204 that is generally cylindrical and substantially aligned with the longitudinal axis 202 .
- the portion 222 of the inner surface 220 extending from the trailing end 206 toward the leading end 204 may be undulating.
- the portion 222 of the inner surface 220 extending from the trailing end 206 toward the leading end 204 may not be generally cylindrical.
- the portion 222 of the inner surface 220 extending from the trailing end 206 toward the leading end 204 may describe a generally frustoconical profile.
- the inner surface 220 of the body 210 includes an inwardly extending shoulder 224 located between the leading end 204 and the portion of the inner surface 220 that extends from the trailing end 206 toward the leading end 204 .
- the shoulder 224 faces toward the trailing end 206 and extends substantially perpendicular to the longitudinal axis 202 .
- the shoulder 224 may extend at angle of from eighty-five to ninety degrees to the longitudinal axis 202 .
- it is contemplated that the shoulder 224 may extend at an acute angle to the longitudinal axis 202 .
- the shoulder 224 may extend at an acute angle toward the trailing end 206 and toward the longitudinal axis 202 .
- the shoulder 224 may include a profile, such as a “V” shaped profile.
- the inner surface 220 of the body 210 includes a first taper 226 between the shoulder 224 and the leading end 204 .
- the first taper 226 describes a generally frustoconical profile, although one or more alternative profiles, such as a curve, are contemplated in some embodiments.
- the first taper 226 is shown having an angle 226 a with respect to the longitudinal axis 202 .
- the first taper 226 is oriented such that an inner diameter of the body 210 at a first location 232 on the first taper 226 proximal to the leading end 204 is greater than an inner diameter of the body 210 at a second location 234 distal from the leading end 204 .
- the inner surface 220 of the body 210 includes a second taper 228 between the shoulder 224 and the first taper 226 .
- the second taper 228 describes a generally frustoconical profile, although one or more alternative profiles, such as a curve or other polygonal profile, are contemplated in some embodiments.
- the second taper 228 is shown having an angle 228 a with respect to the longitudinal axis 202 .
- the second taper 228 is oriented such that an inner diameter of the body 210 at the second location 234 is greater than an inner diameter of the body 210 at a third location 236 on the second taper 228 , the third location 236 being proximal to the shoulder 224 .
- the angle 228 a is different from the angle 226 a .
- the first and second tapers 226 , 228 may have the same or different angles 226 a , 228 a or alternative profiles.
- the first location 232 is on the first taper 226 at the leading end 204
- the second location 234 is at a meeting point of the first taper 226 and the second taper 228
- the third location 236 is at the shoulder 224 .
- the first location 232 may be at any location between the leading end 204 and the shoulder 224 .
- the second location 234 may be at any location between the first location 232 and the shoulder 224 .
- the third location 236 may be at any location between the second location 234 and the shoulder 224 .
- the second taper 228 may not meet with the first taper 226 .
- the inner surface 220 may include a generally cylindrical section and/or an enlarged section between the first taper 226 and the second taper 228 .
- the second taper 228 may be omitted.
- the inner surface 220 may include a generally cylindrical section and/or an enlarged section between the first taper 226 and the shoulder 224 .
- the first taper 226 may extend up to the shoulder 224 .
- the seal unit 200 is at least partially disposed around the lower mandrel segment 112 and at least partially disposed around the center mandrel segment 160 .
- the generally cylindrical portion 222 of the inner surface 220 of the seal unit 200 that extends from the trailing end 206 of the seal unit 200 is disposed around the generally cylindrical portion 163 of the outer surface 162 of the center mandrel segment 160 .
- the first taper 226 of the inner surface 220 of the seal unit 200 is disposed around the slope 118 of the outer surface 116 of the lower mandrel segment 112 .
- the angle of the first taper 226 is substantially equal (such as differing by zero degrees to two degrees) to the angle 118 a of the slope 118 . In some embodiments, it is contemplated that the angle of the first taper 226 may be greater than the angle 118 a of the slope 118 . In some embodiments, it is contemplated that the angle of the first taper 226 may be less than the angle 118 a of the slope 118 .
- the second taper 228 of the inner surface 220 of the seal unit 200 is disposed around the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 . It is contemplated that the second taper 228 of the inner surface 220 of the seal unit 200 may be dimensioned such that the second taper 228 provides an interference fit around the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 .
- the inner diameter of the body 210 of the seal unit 200 at the third location 236 (proximal to the shoulder 224 ) on the second taper 228 may be less than an outer diameter of the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 .
- the second taper 228 provides an interference fit around the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 even if the inner diameter of the body 210 of the seal unit 200 at the second location 234 is greater than or equal to the outer diameter of the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 .
- the portion of the seal unit 200 between the first taper 226 of the inner surface 220 and the shoulder 224 may be disposed around the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 .
- first taper 226 of the inner surface 220 of the seal unit 200 extends to the shoulder 224 of the inner surface 220 of the seal unit 200 , it is contemplated that at least a portion of the first taper 226 may be disposed around the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 . Additionally, in such embodiments, it is contemplated the first taper 226 of the inner surface 220 of the seal unit 200 may be dimensioned such that the first taper 226 provides an interference fit around the first generally cylindrical portion 117 of the outer surface 116 of the lower mandrel segment 112 .
- an anti-extrusion assembly 300 is disposed around the lower mandrel segment 112 between the seal unit 200 and the leading end 104 of the wiper plug 100 .
- the anti-extrusion assembly 300 is disposed around the second generally cylindrical portion 152 of the outer surface 116 of the lower mandrel segment 112 .
- the anti-extrusion assembly 300 is illustrated in detail in an exploded cross-sectional view in FIG. 4 .
- the anti-extrusion assembly 300 has a longitudinal axis 302 that, in use, is substantially coincident with the longitudinal axis 102 of the wiper plug 100 .
- the longitudinal axis 302 of the anti-extrusion assembly 300 may intersect the longitudinal axis 102 of the wiper plug 100 at an angle of from zero degrees to two degrees.
- the anti-extrusion assembly 300 includes a setting ring 310 , a retaining ring 330 , and a ductile ring 350 located between the setting ring 310 and the retaining ring 330 .
- the setting ring 310 has a base 312 and an annular projection 316 extending outwardly from the base 312 .
- the base 312 extends longitudinally from the projection 316 .
- the projection 316 has a first surface 322 that, in use, faces the trailing end 106 of the wiper plug 100 .
- the first surface 322 is illustrated as being substantially perpendicular to the longitudinal axis 302 .
- the first surface 322 may extend at angle of from eighty-five to ninety degrees to the longitudinal axis 202 .
- the first surface 322 may include a portion that is frustoconical, and thus may be at an acute angle to the longitudinal axis 302 .
- the first surface 322 may include a portion that extends outwardly from the base 312 and toward the trailing end 106 of the wiper plug 100 .
- the projection 316 has a second surface 324 that, in use, faces the leading end 104 of the wiper plug 100 .
- the second surface 324 is frustoconical, and is at an acute angle 324 a to datum line 302 ′ which is parallel to the longitudinal axis 302 .
- the retaining ring 330 has a first recess 332 configured to accommodate at least a portion of the base 312 of the setting ring 310 .
- the first recess 332 is at least partially defined by a first shoulder 334 that, in use, faces the trailing end 106 of the wiper plug 100 .
- the retaining ring 330 has a second recess 336 configured to accommodate at least a portion of the ridge 154 of the lower mandrel segment 112 .
- the second recess 336 is at least partially defined by a second shoulder 338 that, in use, faces the ridge 154 of the lower mandrel segment 112 .
- the retaining ring 330 has a surface 342 that, in use, faces the trailing end 106 of the wiper plug 100 .
- the surface is frustoconical, and is at an acute angle 342 a to datum line 302 ′ which is parallel to the longitudinal axis 302 .
- the ductile ring 350 is made from a material, such as polytetrafluoroethylene, that possesses flexural strength and is resistant to tearing.
- the ductile ring 350 has a first surface 352 that, in use, faces the trailing end 106 of the wiper plug 100 .
- the first surface 352 is frustoconical, and is at an acute angle 352 a to datum line 302 ′ which is parallel to the longitudinal axis 302 .
- the ductile ring 350 has a second surface 354 that, in use, faces the leading end 104 of the wiper plug 100 .
- the second surface 354 is frustoconical, and is at an acute angle 354 a to datum line 302 ′ which is parallel to the longitudinal axis 302 .
- the angle 324 a of the second surface 324 of the projection 316 of the setting ring 310 may be substantially equal to the angle 352 a of the first surface 352 of the ductile ring 350 .
- the angle 324 a may differ from the angle 352 a by zero to two degrees.
- the angle 324 a of the second surface 324 of the projection 316 of the setting ring 310 may be less than the angle 352 a of the first surface 352 of the ductile ring 350 .
- the angle 324 a of the second surface 324 of the projection 316 of the setting ring 310 may be greater than the angle 352 a of the first surface 352 of the ductile ring 350 .
- the angle 354 a of the second surface 354 of the ductile ring 350 may be substantially equal to the angle 352 a of the first surface 352 of the ductile ring 350 .
- the angle 354 a may differ from the angle 352 a by zero to two degrees.
- the angle 354 a of the second surface 354 of the ductile ring 350 may be less than the angle 352 a of the first surface 352 of the ductile ring 350 .
- the angle 354 a of the second surface 354 of the ductile ring 350 may be greater than the angle 352 a of the first surface 352 of the ductile ring 350 .
- the angle 354 a of the second surface 354 of the ductile ring 350 may be substantially equal to the angle 342 a of the surface 342 of the retaining ring 330 .
- the angle 354 a may differ from the angle 342 a by zero to two degrees.
- the angle 354 a of the second surface 354 of the ductile ring 350 may be less than the angle 342 a of the surface 342 of the retaining ring 330 .
- the angle 354 a of the second surface 354 of the ductile ring 350 may be greater than the angle 342 a of the surface 342 of the retaining ring 330 .
- the nose portion 120 protrudes beyond the anti-extrusion assembly 300 .
- the nose portion 120 may not protrude beyond the anti-extrusion assembly 300 .
- the second recess 336 of the retaining ring 330 accommodates at least a portion of the ridge 154 of the lower mandrel segment 112 .
- the second shoulder 338 of the second recess 336 of the retaining ring 330 is illustrated as abutting the ridge 154 of the lower mandrel segment 112 .
- second shoulder 338 of the second recess 336 of the retaining ring 330 may not abut the ridge 154 of the lower mandrel segment 112 .
- the setting ring 310 is located between the retaining ring 330 and the seal unit 200
- the ductile ring 350 is located between the projection 316 of the setting ring 310 and the frustoconical surface of the retaining ring 330 .
- the second surface 324 of the projection 316 of the setting ring 310 abuts the first surface 352 of the ductile ring 350 .
- the second surface 354 of the ductile ring 350 abuts the frustoconical surface of the retaining ring 330 .
- the anti-extrusion assembly 300 is configured such that movement of the setting ring 310 toward the retaining ring 330 compresses the ductile ring 350 , resulting in deformation of the ductile ring 350 .
- the deformation of the ductile ring 350 transitions the ductile ring 350 from a radially retracted condition to a radially extended condition.
- the base 312 of the setting ring 310 extends into the first recess 332 of the retaining ring 330 .
- a gap 358 exists between the first shoulder 334 of the first recess 332 of the retaining ring 330 and the end 314 of the base 312 that extends from the projection 316 into the first recess 332 of the retaining ring 330 .
- the ductile ring 350 Upon mounting the anti-extrusion assembly 300 onto the lower mandrel segment 112 , the ductile ring 350 is disposed around, and in contact with, a portion of the base 312 of the setting ring 310 that does not extend into the first recess 332 of the retaining ring 330 . In some embodiments, it is contemplated that the base 312 of the setting ring 310 may not extend into the first recess 332 of the retaining ring 330 upon mounting the anti-extrusion assembly 300 onto the lower mandrel segment 112 . In some embodiments, it is contemplated that the ductile ring 350 may not be disposed around the base 312 of the setting ring 310 . For example, the ductile ring 350 may be disposed around, and in contact with, the second cylindrical portion 152 of the outer surface 116 of the lower mandrel segment 112 .
- FIG. 1 illustrates that the leading end 204 of the seal unit 200 abuts the anti-extrusion assembly 300 at the first surface 322 of the projection 316 of the setting ring 310 .
- the leading end 204 of the seal unit 200 may not abut the anti-extrusion assembly 300 .
- the shoulder 224 of the body 210 of the seal unit 200 is disposed proximal to, and facing, an end 168 of the center mandrel segment 160 .
- the shoulder 224 of the body 210 of the seal unit 200 abuts the end 168 of the center mandrel segment 160 . In some embodiments, it is contemplated that upon assembly of the wiper plug 100 , the shoulder 224 of the body 210 of the seal unit 200 bears against the end 168 of the center mandrel segment 160 .
- the seal unit 200 may apply a preload to the anti-extrusion assembly 300 .
- the preload may cause the setting ring 310 to apply sufficient force on the ductile ring 350 to deform the ductile ring 350 .
- an outer diameter of the ductile ring 350 may become enlarged.
- the preload may not cause the setting ring 310 to apply sufficient force on the ductile ring 350 to deform the ductile ring 350 .
- a wiper plug in some embodiments, includes a mandrel and a seal unit disposed around the mandrel.
- the seal unit includes a body having an inner surface, a leading end, and a trailing end, and one or more fins extending outwardly from the body.
- the inner surface includes a first, generally cylindrical, portion and a second portion.
- the second portion includes an inwardly extending shoulder located between the first portion and the leading end and facing toward the trailing end.
- the shoulder is substantially perpendicular to a longitudinal axis of the mandrel.
- the second portion further includes a first taper between the shoulder and the leading end.
- the seal unit body has a first inner diameter at a first location on the first taper proximal to the leading end and a second inner diameter at a second location on the first taper distal from the leading end. The first inner diameter is greater than the second inner diameter.
- an outer surface of the mandrel includes a slope, and the first taper is disposed adjacent the slope.
- the inner surface of the seal unit further includes a second taper between the shoulder and the first taper.
- the body of the seal unit has a third inner diameter at a third location on the second taper proximal to the shoulder, the third inner diameter less than the second inner diameter.
- the wiper plug includes an anti-extrusion assembly disposed about the mandrel at the leading end of the seal unit.
- FIGS. 5A to 9 illustrate the wiper plug 100 during several stages of operation.
- the wiper plug 100 is inserted into a bore, such as a wellbore or other bore, such as a pipeline.
- the wiper plug 100 is illustrated disposed within a tubular 405 .
- the tubular 405 may be a liner or a casing of a wellbore.
- the wiper plug 100 is suspended from a support 410 , such as a portion of a liner hanger running/setting tool. Each retainer of the wiper plug 100 projects radially outward into a recess 412 of the support 410 .
- the recess 412 may extend around an entire inner circumference of the support 410 .
- the upper seat sleeve 180 in the position shown in FIG. 5A prevents each retainer from moving radially inwardly.
- a first obturating object shown in FIG. 5A as a ball 414 , is dropped into the wellbore, and conveyed by gravity and/or by pumping a fluid through a work string (not shown) to the wiper plug 100 .
- the ball 414 is illustrated as having landed on the profile 142 of the lower seat sleeve 140 .
- the ball 414 landed on the profile 142 of the lower seat sleeve 140 blocks fluid communication through the wiper plug 100 .
- Pressure is exerted against the ball 414 , and upon reaching a first threshold, triggers activation of one or more tools in the wellbore. For example, the pressure may cause a liner hanger to become anchored in the wellbore.
- FIG. 5B illustrates a variation of FIG. 5A in the deployment of the wiper plug 100 .
- wiper plug 100 ′ represents at least one embodiment of the wiper plug 100 in which the anti-extrusion assembly 300 is at least partially energized when pressure is exerted against the ball 414 .
- the energizing of the anti-extrusion assembly 300 may result from a preload applied by the seal unit 200 , such as described above.
- the energizing of the anti-extrusion assembly 300 may result from the pressure exerted against the ball 414 also being exerted against the seal unit 200 in the annular space 408 between the mandrel 110 and the tubular 405 .
- pressure exerted against the ball 414 may be communicated to the annular space 408 via a port in the support 410 and/or around the one or more retainers 172 .
- the preload and/or pressure exerted on the seal unit 200 may result in a force being transferred from the seal unit 200 to the first surface 322 of the projection 316 of the setting ring 310 of the anti-extrusion assembly 300 .
- a force of sufficient magnitude applied via the seal unit 200 to the setting ring 310 of the anti-extrusion assembly 300 causes the setting ring 310 to move toward the retaining ring 330 .
- the second shoulder 338 of the second recess 336 of the retaining ring 330 abuts the ridge 154 of the lower mandrel segment 112 , the retaining ring 330 is prevented from moving away from the setting ring 310 . Therefore, movement of the setting ring 310 toward the retaining ring 330 compresses the ductile ring 350 , resulting in deformation of the ductile ring 350 .
- the configuration of the second surface 324 of the projection 316 of the setting ring 310 , the first 352 and second 354 surfaces of the ductile ring 350 , and the corresponding surface 342 of the retaining ring 330 promote deformation of the ductile ring 350 radially outward such that an outer diameter of the ductile ring 350 becomes enlarged, as illustrated in FIG. 5B .
- the outer diameter of the ductile ring 350 may become enlarged to the extent that the ductile ring 350 contacts the tubular 405 .
- the ductile ring 350 makes a 360 degree contact with the tubular 405 .
- the ductile ring 350 may not contact the tubular 405 . In some embodiments, it is contemplated that the extent to which the ductile ring 350 may be deformed outwardly from between the projection 316 of the setting ring 310 and the retaining ring 330 is limited at least in part by the end 314 of the base 312 of the setting ring contacting the first shoulder 334 of the first recess 332 of the retaining ring 330 .
- the force imparted on the seal unit 200 by the pressure applied on the displacement fluid may cause at least a portion 240 of the seal unit 200 to become extruded, as exemplified in FIG. 5B .
- a susceptibility of the seal unit 200 to extrusion may be exacerbated by exposure to the elevated temperatures that typically exist in wellbores. Extrusion of a fin 212 / 214 / 216 / 218 of the seal unit 200 may compromise the integrity of the seals between the fin 212 / 214 / 216 / 218 and the surrounding tubular 405 .
- the wiper plug 100 ′ of the present disclosure as shown in FIG.
- extrusion of the seal unit 200 at the leading end 204 of the seal unit 200 is limited by the anti-extrusion assembly 300 .
- extrusion of the leading end 204 is restricted, and extrusion of the seal unit at the leading fin 212 is inhibited.
- sealing integrity of at least the leading fin 212 against the surrounding tubular 405 is maintained.
- FIG. 6A illustrates a continuation of the operation depicted in FIG. 5A , and shows the wiper plug 100 after the release of the lower seat sleeve 140 .
- the lower seat sleeve 140 and the ball 414 move into the catcher 132 ; the lower seat sleeve 140 rests against the ledge 136 around the end port 134 of the catcher 132 .
- Fluid communication through the wiper plug 100 is now reestablished since fluid may travel through the one or more side ports 138 of the catcher 132 .
- FIG. 6B illustrates a continuation of the operation depicted in FIG. 5B , and shows the wiper plug 100 ′ after the release of the lower seat sleeve 140 .
- the lower seat sleeve 140 and the ball 414 move into the catcher 132 ; the lower seat sleeve 140 rests against the ledge 136 around the end port 134 of the catcher 132 .
- Fluid communication through the wiper plug 100 ′ is now reestablished since fluid may travel through the one or more side ports 138 of the catcher 132 .
- FIG. 6B illustrates the ductile ring 350 remaining radially outwardly deformed to an extent similar to that depicted in FIG. 5B .
- the ductile ring 350 may become at least partially radially retracted.
- the reestablishment of fluid communication through the wiper plug 100 ′ results in a reduction of the pressure exerted on the seal unit 200 .
- the seal unit 200 may return back towards the shape and positioning shown in FIG. 1 . Such a return may reduce the force exerted by the seal unit 200 on the setting ring 310 .
- the ductile ring 350 may at least partially retract back towards the shape and positioning shown in FIG. 1 .
- FIGS. 5A to 6B of landing the first obturating object in the lower seat sleeve 140 and releasing the lower seat sleeve 140 may be omitted.
- FIG. 7A illustrates not only a continuation of the operation depicted in FIG. 6A , but also relevant operations for embodiments in which landing the first obturating object in the lower seat sleeve 140 and releasing the lower seat sleeve 140 are omitted.
- a cement slurry is pumped into the wellbore and through the wiper plug 100 .
- FIG. 7A as a dart 416 , is dropped into the wellbore, and conveyed by gravity and/or by pumping a displacement fluid, such as a drilling fluid, through a work string (not shown) to the wiper plug 100 .
- a displacement fluid such as a drilling fluid
- FIG. 7A the dart 416 is illustrated as having landed on the profile 182 of the upper seat sleeve 180 .
- the dart 416 landed on the profile 182 of the upper seat sleeve 180 blocks fluid communication through the wiper plug 100 .
- FIG. 7B illustrates a continuation of the operation depicted in FIG. 6B .
- FIG. 7B also illustrates relevant operations for embodiments of wiper plug 100 ′ in which landing the first obturating object in the lower seat sleeve 140 and releasing the lower seat sleeve 140 are omitted.
- a cement slurry is pumped into the wellbore and through the wiper plug 100 ′.
- the second obturating object shown in FIG. 7B as dart 416 , is dropped into the wellbore, and conveyed by gravity and/or by pumping a displacement fluid, such as a drilling fluid, through a work string (not shown) to the wiper plug 100 ′.
- a displacement fluid such as a drilling fluid
- the dart 416 is illustrated as having landed on the profile 182 of the upper seat sleeve 180 .
- the dart 416 landed on the profile 182 of the upper seat sleeve 180 blocks fluid communication through the wiper plug 100 ′.
- FIG. 7B shows the anti-extrusion assembly 300 of wiper plug 100 ′ is at least partially energized when pressure is exerted against the dart 416 .
- the energizing of the anti-extrusion assembly 300 may result from a preload applied by the seal unit 200 , such as described above.
- the energizing of the anti-extrusion assembly 300 may result from the pressure exerted against the dart 416 also being exerted against the seal unit 200 in the annular space 408 between the mandrel 110 and the tubular 405 .
- pressure exerted against the dart 416 may be communicated to the annular space 408 via a port in the support 410 and/or around the one or more retainers 172 . It is contemplated that the preload and/or pressure exerted on the seal unit 200 may result in a force being transferred from the seal unit 200 to the first surface 322 of the projection 316 of the setting ring 310 of the anti-extrusion assembly 300 .
- FIG. 8A illustrates a continuation of the operation depicted in FIG. 7A , and shows the wiper plug 100 after the release of the upper seat sleeve 180 .
- the application of pressure against the dart 416 to a third threshold causes the release of the upper seat sleeve 180 .
- the force on the upper seat sleeve 180 resulting from the pressure may cause the releasable fastener 184 to fail.
- the upper seat sleeve 180 and the dart 416 move down until the external taper 194 of the upper seat sleeve 180 engages the taper 166 of the bore 164 of the center mandrel segment 160 and the lock ring 188 in the center mandrel segment 160 engages the recess 192 in the upper seat sleeve 180 .
- the external taper 194 of the upper seat sleeve 180 and/or the taper 166 of the bore 164 of the center mandrel segment 160 may be omitted.
- the upper seat sleeve 180 and the dart 416 move down until the engagement between the lock ring 188 in the center mandrel segment 160 and the recess 192 in the upper seat sleeve 180 prevents further downward movement of the upper seat sleeve 180 . In some embodiments, it is contemplated that the upper seat sleeve 180 and the dart 416 move down until the lower end 196 of the upper seat sleeve 180 engages a portion of the lower mandrel segment 112 .
- each corresponding retainer 172 is no longer prevented from moving radially inward.
- Continued application of pressure to the dart 416 results in a downward force on the wiper plug 100 which promotes the radial inward movement of each retainer 172 due to the interaction between each retainer and the corresponding recess 412 of the support 410 .
- the radial inward movement of each retainer 172 thus releases the wiper plug 100 from the support 410 .
- FIG. 8B illustrates a continuation of the operation depicted in FIG. 7B , and shows the wiper plug 100 ′ after the release of the upper seat sleeve 180 .
- the application of pressure against the dart 416 to a third threshold causes the release of the upper seat sleeve 180 .
- the force on the upper seat sleeve 180 resulting from the pressure may cause the releasable fastener 184 to fail.
- the upper seat sleeve 180 and the dart 416 move down until the external taper 194 of the upper seat sleeve 180 engages the taper 166 of the bore 164 of the center mandrel segment 160 and the lock ring 188 in the center mandrel segment 160 engages the recess 192 in the upper seat sleeve 180 .
- the external taper 194 of the upper seat sleeve 180 and/or the taper 166 of the bore 164 of the center mandrel segment 160 may be omitted.
- the upper seat sleeve 180 and the dart 416 move down until the engagement between the lock ring 188 in the center mandrel segment 160 and the recess 192 in the upper seat sleeve 180 prevents further downward movement of the upper seat sleeve 180 . In some embodiments, it is contemplated that the upper seat sleeve 180 and the dart 416 move down until the lower end 196 of the upper seat sleeve 180 engages a portion of the lower mandrel segment 112 .
- each corresponding retainer 172 is no longer prevented from moving radially inward.
- Continued application of pressure to the dart 416 results in a downward force on the wiper plug 100 ′ which promotes the radial inward movement of each retainer 172 due to the interaction between each retainer and the corresponding recess 412 of the support 410 .
- the radial inward movement of each retainer 172 thus releases the wiper plug 100 ′ from the support 410 .
- FIG. 8B illustrates the ductile ring 350 remaining radially outwardly deformed to an extent similar to that depicted in FIG. 7B .
- the ductile ring 350 may become at least partially radially retracted.
- the release of the wiper plug 100 ′ from the support 410 may result in pressures above and below the seal unit 200 becoming substantially balanced, such as within 50 psi (3.45 bar).
- the seal unit 200 may return back towards the shape and positioning shown in FIG. 1 . Such a return may reduce the force exerted by the seal unit 200 on the setting ring 310 .
- the ductile ring 350 may at least partially retract back towards the shape and positioning shown in FIG. 1 .
- FIG. 9 illustrates a continuation of the operations depicted in FIGS. 8A and 8B , and depicts a termination of the travel of the wiper plug 100 , 100 ′ through the tubular 405 .
- the wiper plug 100 , 100 ′ is engaged with a collar 420 in the tubular 405 .
- the collar 420 has a bore 425 configured to receive at least part of the nose portion 120 of the mandrel 110 of the wiper plug 100 , 100 ′.
- FIG. 9 illustrates the bore 425 receiving the one or more seals 124 and the lock ring 126 of the nose portion 120 of the mandrel 110 of the wiper plug 100 , 100 ′.
- FIG. 9 illustrates the anti-extrusion assembly 300 in an energized condition.
- the anti-extrusion assembly 300 is not in an energized condition after the wiper plug 100 , 100 ′ has landed in the collar 420 .
- the anti-extrusion assembly 300 is in an energized condition after the wiper plug 100 , 100 ′ has landed in the collar 420 .
- the energizing of the anti-extrusion assembly 300 may occur prior to the wiper plug 100 ′ landing in the collar 420 , such as in any one or more of the operations depicted in FIGS. 5B, 6B, 7B , and/or 8 B, and that the anti-extrusion assembly 300 remains at least partially energized after the wiper plug 100 ′ has landed in the collar 420 .
- the energizing of the anti-extrusion assembly 300 may result from a preload applied by the seal unit 200 , such as described above. Alternatively, or additionally, in some embodiments it is contemplated that the energizing of the anti-extrusion assembly 300 may result from a continued application of pressure applied to the displacement fluid after the wiper plug 100 , 100 ′ has landed in the collar 420 . For example, in conducting a pressure test following the landing of the wiper plug 100 , 100 ′ in the collar 420 , pressure applied to the displacement fluid may result in a force being transferred from the seal unit 200 to the first surface 322 of the projection 316 of the setting ring 310 of the anti-extrusion assembly 300 .
- a force of sufficient magnitude applied via the seal unit 200 to the setting ring 310 of the anti-extrusion assembly 300 causes the setting ring 310 to move toward the retaining ring 330 .
- the retaining ring 330 is prevented from moving away from the setting ring 310 , and therefore movement of the setting ring 310 toward the retaining ring 330 compresses the ductile ring 350 , resulting in deformation of the ductile ring 350 .
- the configuration of the second surface 324 of the projection 316 of the setting ring 310 , the first 352 and second 354 surfaces of the ductile ring 350 , and the corresponding surface 342 of the retaining ring 330 promote deformation of the ductile ring 350 radially outward such that an outer diameter of the ductile ring 350 becomes enlarged, as illustrated in FIG. 9 .
- the outer diameter of the ductile ring 350 may become enlarged to the extent that the ductile ring 350 contacts the tubular 405 .
- the ductile ring 350 makes a 360 degree contact with the tubular 405 .
- the ductile ring 350 may not contact the tubular 405 . In some embodiments, it is contemplated that the extent to which the ductile ring 350 may be deformed outwardly from between the projection 316 of the setting ring 310 and the retaining ring 330 is limited at least in part by the end 314 of the base 312 of the setting ring contacting the first shoulder 334 of the first recess 332 of the retaining ring 330 .
- the force imparted on the seal unit 200 by the pressure applied on the displacement fluid may cause at least a portion 240 of the seal unit 200 to become extruded, as exemplified in FIG. 9 . It is contemplated that a susceptibility of the seal unit 200 to extrusion may be exacerbated by exposure to the elevated temperatures that typically exist in wellbores. Extrusion of a fin 212 / 214 / 216 / 218 of the seal unit 200 may compromise the integrity of the seals between the fin 212 / 214 / 216 / 218 and the surrounding tubular 405 . However for the wiper plug 100 , 100 ′ of the present disclosure, as shown in FIG.
- extrusion of the seal unit 200 at the leading end 204 of the seal unit 200 is limited by the anti-extrusion assembly 300 .
- extrusion of the leading end 204 is restricted, and extrusion of the seal unit at the leading fin 212 is inhibited.
- sealing integrity of at least the leading fin 212 against the surrounding tubular 405 is maintained.
- extrusion of the body 210 of the seal unit 200 may compromise the integrity of the seal between the seal unit 200 and the mandrel 110 of the wiper plug 100 , 100 ′.
- the interaction between the seal unit 200 and the slope 118 of the lower mandrel segment 112 limits extrusion of the body 210 of the seal unit 200 , and limits the degree to which sealing contact between the seal unit 200 and the lower mandrel segment 112 may be compromised.
- the mounting of the seal unit 200 around the mandrel 110 is configured to be an interference fit, it is contemplated that the interference fit may assist in maintaining the integrity of the seal between the seal unit 200 and the lower mandrel segment 112 .
- wiper plugs 100 , 100 ′ of the present disclosure provide for at least a portion of the seal unit 200 to be maintained in sealing contact with the mandrel 110 and at least a portion of the seal unit 200 to be maintained in sealing contact with the surrounding tubular 405 , and integrity of the seals is preserved.
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Abstract
Description
- Embodiments of the present disclosure generally relate to plugs that are used during the cementing of liners, such as those used in oil, gas, and water wells.
- A wellbore is formed by using a drill bit on a drill string to drill through a geological formation. A drilling fluid, known as mud, is circulated to lubricate the drill bit, remove rock cuttings from the wellbore, and provide a hydrostatic pressure to counteract the in situ pressure of the geological formation. After drilling through the geological formation to a predetermined depth, the drill string and drill bit are removed, and the wellbore is lined by inserting a string of casing into the wellbore. At least a portion of the annulus between the inner surface of the wellbore and casing is filled with cement using a cementing operation. Typically, a cementing operation involves the pumping of a cement slurry through the casing, out of the bottom of the casing, and up the annulus.
- A casing string is hung off from a wellhead located at the top of the wellbore. An equivalent string of tubulars that is hung off from a location within the wellbore below the wellhead is typically referred to as a liner. A liner is deployed to a desired depth in the wellbore using a workstring, and suspended from a previously-installed casing by using a liner hanger. A setting tool is then operated to set a liner hanger against the previously installed casing. The liner hanger may include slips riding outwardly on cones in order to engage the surrounding casing. The setting tool is typically operated by pumping a ball through the workstring to a seat located below the setting tool. Pressure is exerted on the seated ball to operate the setting tool. Thereafter, pressure is increased to release the ball and the ball seat. Usually, after actuating the liner hanger, the liner is cemented in place by pumping a cement slurry down the workstring, into the liner, out of the bottom of the liner, and into the annulus between the liner and the inner surface of the wellbore.
- Wiper plugs are used to segregate the cement slurry from the drilling fluid while the cement slurry travels down the casing or liner. In a liner cementation operation, darts may be used to segregate the cement slurry from other fluids while the cement slurry travels down the workstring. Each dart picks up a corresponding wiper plug that is installed in an upper portion of the liner below the liner hanger to ensure the fluids remain segregated while the cement travels down through the liner. Sometimes, only one dart and a corresponding wiper plug is used; the dart and corresponding wiper plug operate to segregate the cement from fluid, such as drilling fluid, that is pumped after the cement to move the cement out of the bottom of the liner and into the annulus between the liner and the inner surface of the wellbore.
- A wiper plug typically has an elastomeric body mounted on a mandrel and elastomeric external fins that bear against the inner wall of the casing. The fins wipe mud solids and other accumulated debris off the inner wall of the casing. The effectiveness of a wiper plug relies on at least one fin creating a seal against the surrounding casing or liner, and the body sealing against the mandrel. The elastomer material usually has a hardness that provides for structural robustness, such as for wiping of the casing or liner, and resistance to abrasion, yet is sufficiently malleable to be deformed so as to provide the necessary seals. However, the hardness decreases with increasing temperature, and thus at elevated temperatures within wellbores, the elastomeric body and the fins become susceptible to extrusion, which compromises their sealing capability.
- Therefore, there is a need for an improved wiper plug design.
- The present disclosure generally relates to a wiper plug for use in a wellbore or other conduit, such as a pipeline.
- In one embodiment, a wiper plug includes a mandrel having a nose portion at a leading end thereof. A seal unit, including a body and one or more fins extending outwardly from the body, is disposed about the mandrel. An anti-extrusion assembly is disposed about the mandrel at a leading end of the seal unit. The anti-extrusion assembly is arranged to transition between a first configuration, in which the anti-extrusion assembly is not energized, and a second configuration, in which the anti-extrusion assembly is energized. The nose portion protrudes beyond the anti-extrusion assembly.
- In another embodiment, a wiper plug includes a mandrel and a seal unit disposed about the mandrel, the seal unit having a body and one or more fins extending outwardly from the body. An anti-extrusion assembly is disposed about the mandrel at a leading end of the seal unit. The anti-extrusion assembly is arranged to transition between a first configuration, in which the anti-extrusion assembly is not energized, and a second configuration, in which the anti-extrusion assembly is energized, in response to a pressure applied to an obturating object landed in the wiper plug.
- In another embodiment, a wiper plug includes a mandrel and a seal unit disposed around the mandrel. The seal unit includes a body having an inner surface, a leading end, and a trailing end, and one or more fins extending outwardly from the body. The inner surface includes a first, generally cylindrical, portion and a second portion. The second portion includes an inwardly extending shoulder located between the first portion and the leading end and facing toward the trailing end. The shoulder is substantially perpendicular to a longitudinal axis of the mandrel. The second portion further includes a first taper between the shoulder and the leading end. The seal unit body has a first inner diameter at a first location on the first taper proximal to the leading end and a second inner diameter at a second location on the first taper distal from the leading end. The first inner diameter is greater than the second inner diameter.
- In another embodiment, a method includes suspending a wiper plug from a support disposed in a tubular, and energizing an anti-extrusion assembly of the wiper plug while the wiper plug remains suspended from the support.
- So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, as the disclosure may admit to other equally effective embodiments.
-
FIG. 1 is a longitudinal cross-sectional view of a wiper plug. -
FIG. 2 is a longitudinal cross-sectional view of the wiper plug ofFIG. 1 , but with some components omitted. -
FIG. 3 is a longitudinal cross-sectional view of a component of the wiper plug ofFIG. 1 . -
FIG. 4 is a longitudinal cross-sectional view of some components of the wiper plug ofFIG. 1 . -
FIG. 5A is a longitudinal cross-sectional view of the wiper plug ofFIG. 1 during an exemplary phase of operation. -
FIG. 5B is a longitudinal cross-sectional view of an embodiment of the wiper plug ofFIG. 1 during the exemplary phase of operation ofFIG. 5A . -
FIG. 6A is a longitudinal cross-sectional view of the wiper plug ofFIG. 1 during an exemplary phase of operation. -
FIG. 6B is a longitudinal cross-sectional view of an embodiment of the wiper plug ofFIG. 1 during the exemplary phase of operation ofFIG. 6A . -
FIG. 7A is a longitudinal cross-sectional view of the wiper plug ofFIG. 1 during an exemplary phase of operation. -
FIG. 7B is a longitudinal cross-sectional view of an embodiment of the wiper plug ofFIG. 1 during the exemplary phase of operation ofFIG. 7A . -
FIG. 8A is a longitudinal cross-sectional view of the wiper plug ofFIG. 1 during an exemplary phase of operation. -
FIG. 8B is a longitudinal cross-sectional view of an embodiment of the wiper plug ofFIG. 1 during the exemplary phase of operation ofFIG. 8A . -
FIG. 9 is a longitudinal cross-sectional view of the wiper plug ofFIG. 1 during an exemplary phase of operation. - To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.
- The present disclosure concerns wiper plug designs in which extrusion of a resilient component is inhibited. During use, a tendency of a resilient component of a wiper plug to deform detrimentally with a consequential loss of sealing integrity is thereby mitigated. Wiper plugs of the present disclosure provide robust wiping of the inner surface of a casing or liner, and sealing against the casing or liner that is effective at elevated temperatures that exist in a wellbore.
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FIG. 1 is a longitudinal cross-sectional view of awiper plug 100.FIG. 2 is a longitudinal cross-sectional view of thewiper plug 100 ofFIG. 1 , but with some components omitted for clarity. Thewiper plug 100 has alongitudinal axis 102, aleading end 104, and a trailingend 106. For the purpose of orientation, theleading end 104 and trailingend 106 define opposite ends of thewiper plug 100 along thelongitudinal axis 102 according to a direction of travel (418,FIGS. 8A, 8B ) through a tubular for which thewiper plug 100 is configured. Thewiper plug 100 has amandrel 110 that, as illustrated, includes alower mandrel segment 112, acenter mandrel segment 160, and anupper mandrel segment 170. In some embodiments, it is envisaged that themandrel 110 may include greater than three segments. In some embodiments, it is envisaged that themandrel 110 may include fewer than three segments. In some embodiments, it is envisaged that themandrel 110 may be configured as a single component. For the purpose of orientation, theleading end 104 of thewiper plug 100 is also the leading end of themandrel 110, and the trailingend 106 of thewiper plug 100 is also the trailing end of themandrel 110. - The
lower mandrel segment 112 has alongitudinal bore 114 therethrough. Anouter surface 116 of thelower mandrel segment 112 includes afirst portion 117 that is generally cylindrical and substantially aligned with thelongitudinal axis 102. Theouter surface 116 also includes aslope 118 describing a generally frustoconical profile extending at anacute angle 118 a to thelongitudinal axis 102. A first outer diameter of thelower mandrel segment 112 at afirst end 118 b of theslope 118 proximal to theleading end 104 is greater than a second outer diameter of thelower mandrel segment 112 at asecond end 118 c of theslope 118 distal from theleading end 104. - The
outer surface 116 of thelower mandrel segment 112 includes asecond portion 152 that is generally cylindrical and substantially aligned with thelongitudinal axis 102. Theslope 118 is located between the first 117 and second 152 generally cylindrical portions. Theouter surface 116 of thelower mandrel segment 112 includes aridge 154. The second generallycylindrical portion 152 is located between theridge 154 and theslope 118. - The
lower mandrel segment 112 includes anose portion 120 located at theleading end 104. Thenose portion 120 has abore 122 with a diameter that is greater than a diameter of thebore 114 of thelower mandrel segment 112 at a location distal from theleading end 104. In some embodiments, it is envisaged that thenose portion 120 may have abore 122 diameter that is less than or equal to the diameter of thebore 114 of thelower mandrel segment 112 at a location distal from theleading end 104. Thenose portion 120 includes one or more seals 124 (two are illustrated) on an outer surface. Thenose portion 120 includes alock ring 126 on the outer surface. In some embodiments, it is envisaged that the one ormore seals 124 and/or thelock ring 126 may be omitted. - The
lower mandrel segment 112 includes alower seat assembly 130. Thelower seat assembly 130 includes acatcher 132 that extends into thebore 122 of thenose portion 120. Thecatcher 132 is generally tubular, having anend port 134 and one ormore side ports 138. Thecatcher 132 includes aledge 136 around theend port 134. Alower seat sleeve 140 is at least partially disposed in thecatcher 132, and has aprofile 142 configured to interact with an obturating object, such as a dart or a ball. Thelower seat sleeve 140 is held in place by areleasable fastener 144, such as a shear ring, shear pin, collet, latch, or the like. In some embodiments, it is contemplated that thelower seat assembly 130 may be omitted. - The
center mandrel segment 160 is coupled to thelower mandrel segment 112, and has anouter surface 162 including aportion 163 that is generally cylindrical and substantially aligned with thelongitudinal axis 102. Thecenter mandrel segment 160 also has abore 164 that includes ataper 166 from a first bore diameter at afirst location 166 a distal from thelower mandrel segment 112 to a second smaller diameter at asecond location 166 b proximal to thelower mandrel segment 112. Thecenter mandrel segment 160 is coupled to theupper mandrel segment 170. Theupper mandrel segment 170 includes one ormore retainers 172, such as locking dogs, collets, latches, and the like. As illustrated inFIG. 1 , eachretainer 172 is disposed in acorresponding opening 174 in theupper mandrel segment 170. The one ormore retainers 172 secure thewiper plug 100 to a support (410, shown inFIG. 5A ) for deployment. - An
upper seat sleeve 180 having aprofile 182 is at least partially disposed in theupper mandrel segment 170 and at least partially disposed in thecenter mandrel segment 160. Theprofile 182 is configured to interact with an obturating object, such as a dart or a ball. Theupper seat sleeve 180 extends across each opening 174 in the connector, and therefore maintains eachretainer 172 in a radially extended position. Theupper seat sleeve 180 is held in place by areleasable fastener 184, such as a shear ring, shear pin, collet, latch, or the like. An o-ring 186 provides a seal between theupper seat sleeve 180 and thecenter mandrel segment 160. Alock ring 188 in thecenter mandrel segment 160 is configured to engage arecess 192 in theupper seat sleeve 180, as described below. Theupper seat sleeve 180 has anexternal taper 194 such that an outer diameter of theupper seat sleeve 180 at a location distal from alower end 196 of theupper seat sleeve 180 is greater than an outer diameter of theupper seat sleeve 180 at a location proximal to thelower end 196 of theupper seat sleeve 180. - The
mandrel 110—including at least one or more of the components of thelower mandrel segment 112, thecenter mandrel segment 160, or theupper mandrel segment 170—is made of a material that provides structural rigidity, such as a metal, a plastic, or a composite material, such as fiberglass. In some embodiments, it is contemplated that themandrel 110 may be made of a material that may be readily disintegrated upon being drilled through by a standard oilfield drill bit or mill. For example, material may include aluminum. In some embodiments, it is contemplated that themandrel 110 may be made of a material that may be readily dissolved by a suitable solvent. For example, the material may include polylactic acid, and the solvent may include water. - A
seal unit 200 is disposed around themandrel 110. Theseal unit 200 is illustrated inFIG. 3 . Theseal unit 200 has alongitudinal axis 202. When assembled on themandrel 110, thelongitudinal axis 202 of theseal unit 200 is substantially coincident with thelongitudinal axis 102 of thewiper plug 100. For example, thelongitudinal axis 202 of theseal unit 200 may intersect thelongitudinal axis 102 of thewiper plug 100 at an angle of from zero degrees to two degrees. For the purpose of orientation with the description, theseal unit 200 has aleading end 204 consistent with theleading end 104 of thewiper plug 100, and a trailingend 206 consistent with the trailingend 106 of thewiper plug 100. - The
seal unit 200 has abody 210 from which a plurality of fins project outwardly. As illustrated, theseal unit 200 has a leadingfin 212 located proximate to theleading end 204, a trailingfin 218 located proximate to the trailingend 206, and twointermediate fins fin 212 and the trailingfin 218. As illustrated, the leadingfin 212 is configured to perform both a sealing function against a surrounding surface and a wiping function of the surrounding surface when in operation. As illustrated, oneintermediate fin 214 is configured to perform primarily a wiping function of a surrounding surface and secondarily a sealing function against the surrounding surface when in operation. As illustrated, the trailingfin 218 and oneintermediate fin 216 are configured to perform primarily a sealing function against a surrounding surface and secondarily a wiping function of the surrounding surface when in operation. As illustrated, thebody 210 and thefins seal unit 200. However, it is also contemplated that theseal unit 200 may include individual segments. For example, each segment may include a body portion and a fin. - The
seal unit 200 is made of a resilient material, such as an elastomer, that provides resistance to deformation, yet is sufficiently flexible to yield elastically when under load. It is contemplated that the elastomer may have properties tailored for different parts or sections of theseal unit 200. For example, one ormore fins 212/214/216/218 may include an elastomer possessing a greater stiffness than one or moreother fins 212/214/216/218 and/or thebody 210. In some embodiments, it is contemplated that theseal unit 200 may not include additional materials. However, in some embodiments, it is contemplated that theseal unit 200 may include additional materials. For example, theseal unit 200 may include one or more support members in thebody 210 and/or in one ormore fins 212/214/216/218. The one or more support members may provide enhanced stiffness to one or more sections of theseal unit 200. The one or more support members may be made of metal, such as aluminum, or a composite, such as fiberglass. - Although four
fins seal unit 200 may have any suitable number of fins, such as one fin, two fins, three fins, four fins, five fins, six fins, seven fins, or more than seven fins. Additionally, it is contemplated that any suitable number of the fins of the seal unit 200 (such as no fins, one fin, two fins, three fins, or more than three fins) may be configured to perform primarily a wiping function of a surrounding surface and secondarily a sealing function against the surrounding surface when in operation. Additionally, it is contemplated that any suitable number of the fins of the seal unit 200 (such as no fins, one fin, two fins, three fins, or more than three fins) may be configured to primarily a sealing function against a surrounding surface and secondarily a wiping function of the surrounding surface when in operation. - The
body 210 has aninner surface 220 that includes aportion 222 extending from the trailingend 206 toward theleading end 204 that is generally cylindrical and substantially aligned with thelongitudinal axis 202. In some embodiments, it is contemplated that theportion 222 of theinner surface 220 extending from the trailingend 206 toward theleading end 204 may be undulating. In some embodiments, it is contemplated that theportion 222 of theinner surface 220 extending from the trailingend 206 toward theleading end 204 may not be generally cylindrical. For example, theportion 222 of theinner surface 220 extending from the trailingend 206 toward theleading end 204 may describe a generally frustoconical profile. - The
inner surface 220 of thebody 210 includes an inwardly extendingshoulder 224 located between theleading end 204 and the portion of theinner surface 220 that extends from the trailingend 206 toward theleading end 204. Theshoulder 224 faces toward the trailingend 206 and extends substantially perpendicular to thelongitudinal axis 202. For example, theshoulder 224 may extend at angle of from eighty-five to ninety degrees to thelongitudinal axis 202. In some embodiments, it is contemplated that theshoulder 224 may extend at an acute angle to thelongitudinal axis 202. For example, theshoulder 224 may extend at an acute angle toward the trailingend 206 and toward thelongitudinal axis 202. Alternatively, or additionally, theshoulder 224 may include a profile, such as a “V” shaped profile. - The
inner surface 220 of thebody 210 includes afirst taper 226 between theshoulder 224 and theleading end 204. As illustrated, thefirst taper 226 describes a generally frustoconical profile, although one or more alternative profiles, such as a curve, are contemplated in some embodiments. Thefirst taper 226 is shown having anangle 226 a with respect to thelongitudinal axis 202. Thefirst taper 226 is oriented such that an inner diameter of thebody 210 at afirst location 232 on thefirst taper 226 proximal to theleading end 204 is greater than an inner diameter of thebody 210 at asecond location 234 distal from theleading end 204. - The
inner surface 220 of thebody 210 includes asecond taper 228 between theshoulder 224 and thefirst taper 226. Thesecond taper 228 describes a generally frustoconical profile, although one or more alternative profiles, such as a curve or other polygonal profile, are contemplated in some embodiments. Thesecond taper 228 is shown having anangle 228 a with respect to thelongitudinal axis 202. Thesecond taper 228 is oriented such that an inner diameter of thebody 210 at thesecond location 234 is greater than an inner diameter of thebody 210 at athird location 236 on thesecond taper 228, thethird location 236 being proximal to theshoulder 224. In this embodiment, theangle 228 a is different from theangle 226 a. However, it is contemplated the first andsecond tapers different angles - The
first location 232 is on thefirst taper 226 at theleading end 204, thesecond location 234 is at a meeting point of thefirst taper 226 and thesecond taper 228, and thethird location 236 is at theshoulder 224. In some embodiments, it is contemplated that thefirst location 232 may be at any location between theleading end 204 and theshoulder 224. In some embodiments, it is contemplated that thesecond location 234 may be at any location between thefirst location 232 and theshoulder 224. In some embodiments, it is contemplated that thethird location 236 may be at any location between thesecond location 234 and theshoulder 224. In some embodiments, it is contemplated that thesecond taper 228 may not meet with thefirst taper 226. For example, theinner surface 220 may include a generally cylindrical section and/or an enlarged section between thefirst taper 226 and thesecond taper 228. - In some embodiments, it is contemplated that the
second taper 228 may be omitted. For example, theinner surface 220 may include a generally cylindrical section and/or an enlarged section between thefirst taper 226 and theshoulder 224. Alternatively, thefirst taper 226 may extend up to theshoulder 224. - Returning to
FIG. 1 , theseal unit 200 is at least partially disposed around thelower mandrel segment 112 and at least partially disposed around thecenter mandrel segment 160. As illustrated, the generallycylindrical portion 222 of theinner surface 220 of theseal unit 200 that extends from the trailingend 206 of theseal unit 200 is disposed around the generallycylindrical portion 163 of theouter surface 162 of thecenter mandrel segment 160. Additionally, thefirst taper 226 of theinner surface 220 of theseal unit 200 is disposed around theslope 118 of theouter surface 116 of thelower mandrel segment 112. As illustrated, the angle of thefirst taper 226 is substantially equal (such as differing by zero degrees to two degrees) to theangle 118 a of theslope 118. In some embodiments, it is contemplated that the angle of thefirst taper 226 may be greater than theangle 118 a of theslope 118. In some embodiments, it is contemplated that the angle of thefirst taper 226 may be less than theangle 118 a of theslope 118. - In the configuration illustrated in
FIG. 1 , and with reference toFIGS. 1, 2, and 3 , thesecond taper 228 of theinner surface 220 of theseal unit 200 is disposed around the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112. It is contemplated that thesecond taper 228 of theinner surface 220 of theseal unit 200 may be dimensioned such that thesecond taper 228 provides an interference fit around the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112. For example, the inner diameter of thebody 210 of theseal unit 200 at the third location 236 (proximal to the shoulder 224) on thesecond taper 228 may be less than an outer diameter of the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112. In such an example, thesecond taper 228 provides an interference fit around the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112 even if the inner diameter of thebody 210 of theseal unit 200 at thesecond location 234 is greater than or equal to the outer diameter of the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112. - In embodiments in which the
second taper 228 of theinner surface 220 of theseal unit 200 is omitted, and there exists a portion of theseal unit 200body 210 between thefirst taper 226 of theinner surface 220 and theshoulder 224, it is contemplated that the portion of theseal unit 200 between thefirst taper 226 of theinner surface 220 and theshoulder 224 may be disposed around the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112. - In embodiments in which the
first taper 226 of theinner surface 220 of theseal unit 200 extends to theshoulder 224 of theinner surface 220 of theseal unit 200, it is contemplated that at least a portion of thefirst taper 226 may be disposed around the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112. Additionally, in such embodiments, it is contemplated thefirst taper 226 of theinner surface 220 of theseal unit 200 may be dimensioned such that thefirst taper 226 provides an interference fit around the first generallycylindrical portion 117 of theouter surface 116 of thelower mandrel segment 112. - Continuing with
FIG. 1 , ananti-extrusion assembly 300 is disposed around thelower mandrel segment 112 between theseal unit 200 and theleading end 104 of thewiper plug 100. Theanti-extrusion assembly 300 is disposed around the second generallycylindrical portion 152 of theouter surface 116 of thelower mandrel segment 112. Theanti-extrusion assembly 300 is illustrated in detail in an exploded cross-sectional view inFIG. 4 . Theanti-extrusion assembly 300 has alongitudinal axis 302 that, in use, is substantially coincident with thelongitudinal axis 102 of thewiper plug 100. For example, thelongitudinal axis 302 of theanti-extrusion assembly 300 may intersect thelongitudinal axis 102 of thewiper plug 100 at an angle of from zero degrees to two degrees. Theanti-extrusion assembly 300 includes asetting ring 310, a retainingring 330, and aductile ring 350 located between the settingring 310 and the retainingring 330. - The
setting ring 310 has abase 312 and anannular projection 316 extending outwardly from thebase 312. Thebase 312 extends longitudinally from theprojection 316. Theprojection 316 has afirst surface 322 that, in use, faces the trailingend 106 of thewiper plug 100. Thefirst surface 322 is illustrated as being substantially perpendicular to thelongitudinal axis 302. For example, thefirst surface 322 may extend at angle of from eighty-five to ninety degrees to thelongitudinal axis 202. However, in some embodiments, thefirst surface 322 may include a portion that is frustoconical, and thus may be at an acute angle to thelongitudinal axis 302. For example, thefirst surface 322 may include a portion that extends outwardly from thebase 312 and toward the trailingend 106 of thewiper plug 100. Theprojection 316 has asecond surface 324 that, in use, faces theleading end 104 of thewiper plug 100. Thesecond surface 324 is frustoconical, and is at anacute angle 324 a todatum line 302′ which is parallel to thelongitudinal axis 302. - The retaining
ring 330 has afirst recess 332 configured to accommodate at least a portion of thebase 312 of thesetting ring 310. Thefirst recess 332 is at least partially defined by afirst shoulder 334 that, in use, faces the trailingend 106 of thewiper plug 100. The retainingring 330 has asecond recess 336 configured to accommodate at least a portion of theridge 154 of thelower mandrel segment 112. Thesecond recess 336 is at least partially defined by asecond shoulder 338 that, in use, faces theridge 154 of thelower mandrel segment 112. The retainingring 330 has asurface 342 that, in use, faces the trailingend 106 of thewiper plug 100. The surface is frustoconical, and is at anacute angle 342 a todatum line 302′ which is parallel to thelongitudinal axis 302. - The
ductile ring 350 is made from a material, such as polytetrafluoroethylene, that possesses flexural strength and is resistant to tearing. Theductile ring 350 has afirst surface 352 that, in use, faces the trailingend 106 of thewiper plug 100. Thefirst surface 352 is frustoconical, and is at anacute angle 352 a todatum line 302′ which is parallel to thelongitudinal axis 302. Theductile ring 350 has asecond surface 354 that, in use, faces theleading end 104 of thewiper plug 100. Thesecond surface 354 is frustoconical, and is at anacute angle 354 a todatum line 302′ which is parallel to thelongitudinal axis 302. - In some embodiments, it is contemplated that the
angle 324 a of thesecond surface 324 of theprojection 316 of thesetting ring 310 may be substantially equal to theangle 352 a of thefirst surface 352 of theductile ring 350. For example, theangle 324 a may differ from theangle 352 a by zero to two degrees. In some embodiments, it is contemplated that theangle 324 a of thesecond surface 324 of theprojection 316 of thesetting ring 310 may be less than theangle 352 a of thefirst surface 352 of theductile ring 350. In some embodiments, it is contemplated that theangle 324 a of thesecond surface 324 of theprojection 316 of thesetting ring 310 may be greater than theangle 352 a of thefirst surface 352 of theductile ring 350. - In some embodiments, it is contemplated that the
angle 354 a of thesecond surface 354 of theductile ring 350 may be substantially equal to theangle 352 a of thefirst surface 352 of theductile ring 350. For example, theangle 354 a may differ from theangle 352 a by zero to two degrees. In some embodiments, it is contemplated that theangle 354 a of thesecond surface 354 of theductile ring 350 may be less than theangle 352 a of thefirst surface 352 of theductile ring 350. In some embodiments, it is contemplated that theangle 354 a of thesecond surface 354 of theductile ring 350 may be greater than theangle 352 a of thefirst surface 352 of theductile ring 350. - In some embodiments, it is contemplated that the
angle 354 a of thesecond surface 354 of theductile ring 350 may be substantially equal to theangle 342 a of thesurface 342 of the retainingring 330. For example, theangle 354 a may differ from theangle 342 a by zero to two degrees. In some embodiments, it is contemplated that theangle 354 a of thesecond surface 354 of theductile ring 350 may be less than theangle 342 a of thesurface 342 of the retainingring 330. In some embodiments, it is contemplated that theangle 354 a of thesecond surface 354 of theductile ring 350 may be greater than theangle 342 a of thesurface 342 of the retainingring 330. - As illustrated in
FIG. 1 , when theanti-extrusion assembly 300 is mounted on thelower mandrel segment 112, thenose portion 120 protrudes beyond theanti-extrusion assembly 300. In some embodiments, it is contemplated that thenose portion 120 may not protrude beyond theanti-extrusion assembly 300. In some embodiments, it is contemplated that thenose portion 120 may be omitted. - As illustrated in
FIG. 1 , when theanti-extrusion assembly 300 is mounted on thelower mandrel segment 112, thesecond recess 336 of the retainingring 330 accommodates at least a portion of theridge 154 of thelower mandrel segment 112. Thesecond shoulder 338 of thesecond recess 336 of the retainingring 330 is illustrated as abutting theridge 154 of thelower mandrel segment 112. However, in some embodiments, it is contemplated thatsecond shoulder 338 of thesecond recess 336 of the retainingring 330 may not abut theridge 154 of thelower mandrel segment 112. - The
setting ring 310 is located between the retainingring 330 and theseal unit 200, and theductile ring 350 is located between theprojection 316 of thesetting ring 310 and the frustoconical surface of the retainingring 330. Thesecond surface 324 of theprojection 316 of thesetting ring 310 abuts thefirst surface 352 of theductile ring 350. Thesecond surface 354 of theductile ring 350 abuts the frustoconical surface of the retainingring 330. - The
anti-extrusion assembly 300 is configured such that movement of thesetting ring 310 toward the retainingring 330 compresses theductile ring 350, resulting in deformation of theductile ring 350. The deformation of theductile ring 350 transitions theductile ring 350 from a radially retracted condition to a radially extended condition. Thebase 312 of thesetting ring 310 extends into thefirst recess 332 of the retainingring 330. Agap 358 exists between thefirst shoulder 334 of thefirst recess 332 of the retainingring 330 and theend 314 of the base 312 that extends from theprojection 316 into thefirst recess 332 of the retainingring 330. An interaction between thefirst shoulder 334 of thefirst recess 332 of the retainingring 330 and anend 314 of thebase 312 of thesetting ring 310 limits the extent to which thesetting ring 310 may move toward the retainingring 330, and therefore limits the extent to which theductile ring 350 may be deformed. - Upon mounting the
anti-extrusion assembly 300 onto thelower mandrel segment 112, theductile ring 350 is disposed around, and in contact with, a portion of thebase 312 of thesetting ring 310 that does not extend into thefirst recess 332 of the retainingring 330. In some embodiments, it is contemplated that thebase 312 of thesetting ring 310 may not extend into thefirst recess 332 of the retainingring 330 upon mounting theanti-extrusion assembly 300 onto thelower mandrel segment 112. In some embodiments, it is contemplated that theductile ring 350 may not be disposed around thebase 312 of thesetting ring 310. For example, theductile ring 350 may be disposed around, and in contact with, the secondcylindrical portion 152 of theouter surface 116 of thelower mandrel segment 112. -
FIG. 1 illustrates that theleading end 204 of theseal unit 200 abuts theanti-extrusion assembly 300 at thefirst surface 322 of theprojection 316 of thesetting ring 310. However, in some embodiments, it is contemplated that upon assembly of thewiper plug 100, theleading end 204 of theseal unit 200 may not abut theanti-extrusion assembly 300. Additionally, theshoulder 224 of thebody 210 of theseal unit 200 is disposed proximal to, and facing, anend 168 of thecenter mandrel segment 160. In some embodiments, it is contemplated that upon assembly of thewiper plug 100, theshoulder 224 of thebody 210 of theseal unit 200 abuts theend 168 of thecenter mandrel segment 160. In some embodiments, it is contemplated that upon assembly of thewiper plug 100, theshoulder 224 of thebody 210 of theseal unit 200 bears against theend 168 of thecenter mandrel segment 160. - In embodiments in which upon assembly of the
wiper plug 100, theshoulder 224 of thebody 210 of theseal unit 200 bears against theend 168 of thecenter mandrel segment 160 and theleading end 204 of theseal unit 200 abuts theanti-extrusion assembly 300, it is contemplated that theseal unit 200 may apply a preload to theanti-extrusion assembly 300. In some embodiments, it is contemplated that the preload may cause thesetting ring 310 to apply sufficient force on theductile ring 350 to deform theductile ring 350. For example, an outer diameter of theductile ring 350 may become enlarged. In some embodiments, it is contemplated that the preload may not cause thesetting ring 310 to apply sufficient force on theductile ring 350 to deform theductile ring 350. - In some embodiments, a wiper plug includes a mandrel and a seal unit disposed around the mandrel. The seal unit includes a body having an inner surface, a leading end, and a trailing end, and one or more fins extending outwardly from the body. The inner surface includes a first, generally cylindrical, portion and a second portion. The second portion includes an inwardly extending shoulder located between the first portion and the leading end and facing toward the trailing end. The shoulder is substantially perpendicular to a longitudinal axis of the mandrel. The second portion further includes a first taper between the shoulder and the leading end. The seal unit body has a first inner diameter at a first location on the first taper proximal to the leading end and a second inner diameter at a second location on the first taper distal from the leading end. The first inner diameter is greater than the second inner diameter.
- In some embodiments, an outer surface of the mandrel includes a slope, and the first taper is disposed adjacent the slope. In some embodiments, the inner surface of the seal unit further includes a second taper between the shoulder and the first taper. In some embodiments, the body of the seal unit has a third inner diameter at a third location on the second taper proximal to the shoulder, the third inner diameter less than the second inner diameter. In some embodiments, the wiper plug includes an anti-extrusion assembly disposed about the mandrel at the leading end of the seal unit.
-
FIGS. 5A to 9 illustrate thewiper plug 100 during several stages of operation. Thewiper plug 100 is inserted into a bore, such as a wellbore or other bore, such as a pipeline. InFIG. 5A , thewiper plug 100 is illustrated disposed within a tubular 405. It is contemplated that the tubular 405 may be a liner or a casing of a wellbore. Thewiper plug 100 is suspended from asupport 410, such as a portion of a liner hanger running/setting tool. Each retainer of thewiper plug 100 projects radially outward into arecess 412 of thesupport 410. In some embodiments, it is contemplated that therecess 412 may extend around an entire inner circumference of thesupport 410. Theupper seat sleeve 180 in the position shown inFIG. 5A prevents each retainer from moving radially inwardly. - A first obturating object, shown in
FIG. 5A as aball 414, is dropped into the wellbore, and conveyed by gravity and/or by pumping a fluid through a work string (not shown) to thewiper plug 100. InFIG. 5A , theball 414 is illustrated as having landed on theprofile 142 of thelower seat sleeve 140. Theball 414 landed on theprofile 142 of thelower seat sleeve 140 blocks fluid communication through thewiper plug 100. Pressure is exerted against theball 414, and upon reaching a first threshold, triggers activation of one or more tools in the wellbore. For example, the pressure may cause a liner hanger to become anchored in the wellbore. -
FIG. 5B illustrates a variation ofFIG. 5A in the deployment of thewiper plug 100. InFIG. 5B , wiper plug 100′ represents at least one embodiment of thewiper plug 100 in which theanti-extrusion assembly 300 is at least partially energized when pressure is exerted against theball 414. In some embodiments, it is contemplated that the energizing of theanti-extrusion assembly 300 may result from a preload applied by theseal unit 200, such as described above. Alternatively, or additionally, in some embodiments it is contemplated that the energizing of theanti-extrusion assembly 300 may result from the pressure exerted against theball 414 also being exerted against theseal unit 200 in the annular space 408 between themandrel 110 and the tubular 405. For example, pressure exerted against theball 414 may be communicated to the annular space 408 via a port in thesupport 410 and/or around the one or more retainers 172. It is contemplated that the preload and/or pressure exerted on theseal unit 200 may result in a force being transferred from theseal unit 200 to thefirst surface 322 of theprojection 316 of thesetting ring 310 of theanti-extrusion assembly 300. - As illustrated in
FIG. 5B , a force of sufficient magnitude applied via theseal unit 200 to thesetting ring 310 of theanti-extrusion assembly 300 causes thesetting ring 310 to move toward the retainingring 330. Because thesecond shoulder 338 of thesecond recess 336 of the retainingring 330 abuts theridge 154 of thelower mandrel segment 112, the retainingring 330 is prevented from moving away from thesetting ring 310. Therefore, movement of thesetting ring 310 toward the retainingring 330 compresses theductile ring 350, resulting in deformation of theductile ring 350. - The configuration of the
second surface 324 of theprojection 316 of thesetting ring 310, the first 352 and second 354 surfaces of theductile ring 350, and thecorresponding surface 342 of the retainingring 330 promote deformation of theductile ring 350 radially outward such that an outer diameter of theductile ring 350 becomes enlarged, as illustrated inFIG. 5B . In some embodiments, it is contemplated that the outer diameter of theductile ring 350 may become enlarged to the extent that theductile ring 350 contacts the tubular 405. In some embodiments, it is contemplated that theductile ring 350 makes a 360 degree contact with the tubular 405. In other embodiments, it is contemplated that theductile ring 350 may not contact the tubular 405. In some embodiments, it is contemplated that the extent to which theductile ring 350 may be deformed outwardly from between theprojection 316 of thesetting ring 310 and the retainingring 330 is limited at least in part by theend 314 of thebase 312 of the setting ring contacting thefirst shoulder 334 of thefirst recess 332 of the retainingring 330. - Additionally, the force imparted on the
seal unit 200 by the pressure applied on the displacement fluid may cause at least aportion 240 of theseal unit 200 to become extruded, as exemplified inFIG. 5B . It is contemplated that a susceptibility of theseal unit 200 to extrusion may be exacerbated by exposure to the elevated temperatures that typically exist in wellbores. Extrusion of afin 212/214/216/218 of theseal unit 200 may compromise the integrity of the seals between thefin 212/214/216/218 and the surroundingtubular 405. However for thewiper plug 100′ of the present disclosure, as shown inFIG. 5B , extrusion of theseal unit 200 at theleading end 204 of theseal unit 200 is limited by theanti-extrusion assembly 300. Thus, extrusion of theleading end 204 is restricted, and extrusion of the seal unit at the leadingfin 212 is inhibited. Hence, sealing integrity of at least the leadingfin 212 against the surroundingtubular 405 is maintained. - Further application of pressure against the
ball 414 to a second threshold that is higher than the first threshold causes the release of thelower seat sleeve 140. For example, the force on thelower seat sleeve 140 resulting from the pressure may cause thereleasable fastener 144 to fail.FIG. 6A illustrates a continuation of the operation depicted inFIG. 5A , and shows thewiper plug 100 after the release of thelower seat sleeve 140. Thelower seat sleeve 140 and theball 414 move into thecatcher 132; thelower seat sleeve 140 rests against theledge 136 around theend port 134 of thecatcher 132. Fluid communication through thewiper plug 100 is now reestablished since fluid may travel through the one ormore side ports 138 of thecatcher 132. -
FIG. 6B illustrates a continuation of the operation depicted inFIG. 5B , and shows thewiper plug 100′ after the release of thelower seat sleeve 140. Thelower seat sleeve 140 and theball 414 move into thecatcher 132; thelower seat sleeve 140 rests against theledge 136 around theend port 134 of thecatcher 132. Fluid communication through thewiper plug 100′ is now reestablished since fluid may travel through the one ormore side ports 138 of thecatcher 132. -
FIG. 6B illustrates theductile ring 350 remaining radially outwardly deformed to an extent similar to that depicted inFIG. 5B . However, in some embodiments, it is contemplated that theductile ring 350 may become at least partially radially retracted. For example, the reestablishment of fluid communication through thewiper plug 100′ results in a reduction of the pressure exerted on theseal unit 200. Because of the resilient nature of the material of theseal unit 200, theseal unit 200 may return back towards the shape and positioning shown inFIG. 1 . Such a return may reduce the force exerted by theseal unit 200 on thesetting ring 310. In embodiments in which theductile ring 350 retains at least some resiliency, theductile ring 350 may at least partially retract back towards the shape and positioning shown inFIG. 1 . - In some embodiments, it is contemplated that the operations illustrated in
FIGS. 5A to 6B of landing the first obturating object in thelower seat sleeve 140 and releasing thelower seat sleeve 140 may be omitted.FIG. 7A illustrates not only a continuation of the operation depicted inFIG. 6A , but also relevant operations for embodiments in which landing the first obturating object in thelower seat sleeve 140 and releasing thelower seat sleeve 140 are omitted. A cement slurry is pumped into the wellbore and through thewiper plug 100. A second obturating object, shown inFIG. 7A as adart 416, is dropped into the wellbore, and conveyed by gravity and/or by pumping a displacement fluid, such as a drilling fluid, through a work string (not shown) to thewiper plug 100. InFIG. 7A , thedart 416 is illustrated as having landed on theprofile 182 of theupper seat sleeve 180. Thedart 416 landed on theprofile 182 of theupper seat sleeve 180 blocks fluid communication through thewiper plug 100. -
FIG. 7B illustrates a continuation of the operation depicted inFIG. 6B .FIG. 7B also illustrates relevant operations for embodiments ofwiper plug 100′ in which landing the first obturating object in thelower seat sleeve 140 and releasing thelower seat sleeve 140 are omitted. A cement slurry is pumped into the wellbore and through thewiper plug 100′. As described with respect toFIG. 7A , the second obturating object, shown inFIG. 7B asdart 416, is dropped into the wellbore, and conveyed by gravity and/or by pumping a displacement fluid, such as a drilling fluid, through a work string (not shown) to thewiper plug 100′. InFIG. 7B , thedart 416 is illustrated as having landed on theprofile 182 of theupper seat sleeve 180. Thedart 416 landed on theprofile 182 of theupper seat sleeve 180 blocks fluid communication through thewiper plug 100′. -
FIG. 7B shows theanti-extrusion assembly 300 ofwiper plug 100′ is at least partially energized when pressure is exerted against thedart 416. In some embodiments, it is contemplated that the energizing of theanti-extrusion assembly 300 may result from a preload applied by theseal unit 200, such as described above. Alternatively, or additionally, in some embodiments it is contemplated that the energizing of theanti-extrusion assembly 300 may result from the pressure exerted against thedart 416 also being exerted against theseal unit 200 in the annular space 408 between themandrel 110 and the tubular 405. For example, pressure exerted against thedart 416 may be communicated to the annular space 408 via a port in thesupport 410 and/or around the one or more retainers 172. It is contemplated that the preload and/or pressure exerted on theseal unit 200 may result in a force being transferred from theseal unit 200 to thefirst surface 322 of theprojection 316 of thesetting ring 310 of theanti-extrusion assembly 300. -
FIG. 8A illustrates a continuation of the operation depicted inFIG. 7A , and shows thewiper plug 100 after the release of theupper seat sleeve 180. The application of pressure against thedart 416 to a third threshold causes the release of theupper seat sleeve 180. For example, the force on theupper seat sleeve 180 resulting from the pressure may cause thereleasable fastener 184 to fail. Theupper seat sleeve 180 and thedart 416 move down until theexternal taper 194 of theupper seat sleeve 180 engages thetaper 166 of thebore 164 of thecenter mandrel segment 160 and thelock ring 188 in thecenter mandrel segment 160 engages therecess 192 in theupper seat sleeve 180. In some embodiments, it is contemplated that theexternal taper 194 of theupper seat sleeve 180 and/or thetaper 166 of thebore 164 of thecenter mandrel segment 160 may be omitted. In some embodiments, it is contemplated that theupper seat sleeve 180 and thedart 416 move down until the engagement between thelock ring 188 in thecenter mandrel segment 160 and therecess 192 in theupper seat sleeve 180 prevents further downward movement of theupper seat sleeve 180. In some embodiments, it is contemplated that theupper seat sleeve 180 and thedart 416 move down until thelower end 196 of theupper seat sleeve 180 engages a portion of thelower mandrel segment 112. - When the
upper seat sleeve 180 moves down past each opening 174 in theupper mandrel segment 170, eachcorresponding retainer 172 is no longer prevented from moving radially inward. Continued application of pressure to thedart 416 results in a downward force on thewiper plug 100 which promotes the radial inward movement of eachretainer 172 due to the interaction between each retainer and thecorresponding recess 412 of thesupport 410. The radial inward movement of eachretainer 172 thus releases thewiper plug 100 from thesupport 410. Because at least one of thefins seal unit 200 provides a seal against the tubular 405, pressure applied to the displacement fluid results in a corresponding force imparted onto thewiper plug 100. Thus, continued pumping of the displacement fluid moves thewiper plug 100 through the tubular 405 in the direction shown byarrow 418. Hence, theleading end 104 of thewiper plug 100 faces in the direction oftravel 418, and the trailingend 106 of thewiper plug 100 faces against the direction oftravel 418. -
FIG. 8B illustrates a continuation of the operation depicted inFIG. 7B , and shows thewiper plug 100′ after the release of theupper seat sleeve 180. The application of pressure against thedart 416 to a third threshold causes the release of theupper seat sleeve 180. For example, the force on theupper seat sleeve 180 resulting from the pressure may cause thereleasable fastener 184 to fail. Theupper seat sleeve 180 and thedart 416 move down until theexternal taper 194 of theupper seat sleeve 180 engages thetaper 166 of thebore 164 of thecenter mandrel segment 160 and thelock ring 188 in thecenter mandrel segment 160 engages therecess 192 in theupper seat sleeve 180. In some embodiments, it is contemplated that theexternal taper 194 of theupper seat sleeve 180 and/or thetaper 166 of thebore 164 of thecenter mandrel segment 160 may be omitted. In some embodiments, it is contemplated that theupper seat sleeve 180 and thedart 416 move down until the engagement between thelock ring 188 in thecenter mandrel segment 160 and therecess 192 in theupper seat sleeve 180 prevents further downward movement of theupper seat sleeve 180. In some embodiments, it is contemplated that theupper seat sleeve 180 and thedart 416 move down until thelower end 196 of theupper seat sleeve 180 engages a portion of thelower mandrel segment 112. - When the
upper seat sleeve 180 moves down past each opening 174 in theupper mandrel segment 170, eachcorresponding retainer 172 is no longer prevented from moving radially inward. Continued application of pressure to thedart 416 results in a downward force on thewiper plug 100′ which promotes the radial inward movement of eachretainer 172 due to the interaction between each retainer and thecorresponding recess 412 of thesupport 410. The radial inward movement of eachretainer 172 thus releases thewiper plug 100′ from thesupport 410. Because at least one of thefins seal unit 200 provides a seal against the tubular 405, pressure applied to the displacement fluid results in a corresponding force imparted onto thewiper plug 100′. Thus, continued pumping of the displacement fluid moves thewiper plug 100′ through the tubular 405 in the direction shown byarrow 418. Hence, theleading end 104 of thewiper plug 100′ faces in the direction oftravel 418, and the trailingend 106 of thewiper plug 100′ faces against the direction oftravel 418. -
FIG. 8B illustrates theductile ring 350 remaining radially outwardly deformed to an extent similar to that depicted inFIG. 7B . However, in some embodiments, it is contemplated that theductile ring 350 may become at least partially radially retracted. For example, the release of thewiper plug 100′ from thesupport 410 may result in pressures above and below theseal unit 200 becoming substantially balanced, such as within 50 psi (3.45 bar). Because of the resilient nature of the material of theseal unit 200, theseal unit 200 may return back towards the shape and positioning shown inFIG. 1 . Such a return may reduce the force exerted by theseal unit 200 on thesetting ring 310. In embodiments in which theductile ring 350 retains at least some resiliency, theductile ring 350 may at least partially retract back towards the shape and positioning shown inFIG. 1 . - Displacement of the
wiper plug FIG. 9 illustrates a continuation of the operations depicted inFIGS. 8A and 8B , and depicts a termination of the travel of thewiper plug wiper plug collar 420 in the tubular 405. Thecollar 420 has abore 425 configured to receive at least part of thenose portion 120 of themandrel 110 of thewiper plug FIG. 9 illustrates thebore 425 receiving the one ormore seals 124 and thelock ring 126 of thenose portion 120 of themandrel 110 of thewiper plug -
FIG. 9 illustrates theanti-extrusion assembly 300 in an energized condition. In some embodiments, it is contemplated that theanti-extrusion assembly 300 is not in an energized condition after thewiper plug collar 420. In some embodiments, it is contemplated that theanti-extrusion assembly 300 is in an energized condition after thewiper plug collar 420. In some embodiments, it is contemplated that the energizing of theanti-extrusion assembly 300 may occur prior to thewiper plug 100′ landing in thecollar 420, such as in any one or more of the operations depicted inFIGS. 5B, 6B, 7B , and/or 8B, and that theanti-extrusion assembly 300 remains at least partially energized after thewiper plug 100′ has landed in thecollar 420. - In some embodiments, it is contemplated that the energizing of the
anti-extrusion assembly 300 may result from a preload applied by theseal unit 200, such as described above. Alternatively, or additionally, in some embodiments it is contemplated that the energizing of theanti-extrusion assembly 300 may result from a continued application of pressure applied to the displacement fluid after thewiper plug collar 420. For example, in conducting a pressure test following the landing of thewiper plug collar 420, pressure applied to the displacement fluid may result in a force being transferred from theseal unit 200 to thefirst surface 322 of theprojection 316 of thesetting ring 310 of theanti-extrusion assembly 300. - As illustrated in
FIG. 9 , a force of sufficient magnitude applied via theseal unit 200 to thesetting ring 310 of theanti-extrusion assembly 300 causes thesetting ring 310 to move toward the retainingring 330. As described above, the retainingring 330 is prevented from moving away from thesetting ring 310, and therefore movement of thesetting ring 310 toward the retainingring 330 compresses theductile ring 350, resulting in deformation of theductile ring 350. - The configuration of the
second surface 324 of theprojection 316 of thesetting ring 310, the first 352 and second 354 surfaces of theductile ring 350, and thecorresponding surface 342 of the retainingring 330 promote deformation of theductile ring 350 radially outward such that an outer diameter of theductile ring 350 becomes enlarged, as illustrated inFIG. 9 . In some embodiments, it is contemplated that the outer diameter of theductile ring 350 may become enlarged to the extent that theductile ring 350 contacts the tubular 405. In some embodiments, it is contemplated that theductile ring 350 makes a 360 degree contact with the tubular 405. In other embodiments, it is contemplated that theductile ring 350 may not contact the tubular 405. In some embodiments, it is contemplated that the extent to which theductile ring 350 may be deformed outwardly from between theprojection 316 of thesetting ring 310 and the retainingring 330 is limited at least in part by theend 314 of thebase 312 of the setting ring contacting thefirst shoulder 334 of thefirst recess 332 of the retainingring 330. - Additionally, the force imparted on the
seal unit 200 by the pressure applied on the displacement fluid may cause at least aportion 240 of theseal unit 200 to become extruded, as exemplified inFIG. 9 . It is contemplated that a susceptibility of theseal unit 200 to extrusion may be exacerbated by exposure to the elevated temperatures that typically exist in wellbores. Extrusion of afin 212/214/216/218 of theseal unit 200 may compromise the integrity of the seals between thefin 212/214/216/218 and the surroundingtubular 405. However for thewiper plug FIG. 9 , extrusion of theseal unit 200 at theleading end 204 of theseal unit 200 is limited by theanti-extrusion assembly 300. Thus, extrusion of theleading end 204 is restricted, and extrusion of the seal unit at the leadingfin 212 is inhibited. Hence, sealing integrity of at least the leadingfin 212 against the surroundingtubular 405 is maintained. - In the operations described above with respect to
FIGS. 5A to 9 , extrusion of thebody 210 of theseal unit 200 may compromise the integrity of the seal between theseal unit 200 and themandrel 110 of thewiper plug seal unit 200 and theslope 118 of thelower mandrel segment 112 limits extrusion of thebody 210 of theseal unit 200, and limits the degree to which sealing contact between theseal unit 200 and thelower mandrel segment 112 may be compromised. Additionally, in embodiments in which the mounting of theseal unit 200 around themandrel 110 is configured to be an interference fit, it is contemplated that the interference fit may assist in maintaining the integrity of the seal between theseal unit 200 and thelower mandrel segment 112. - Hence, wiper plugs 100, 100′ of the present disclosure provide for at least a portion of the
seal unit 200 to be maintained in sealing contact with themandrel 110 and at least a portion of theseal unit 200 to be maintained in sealing contact with the surrounding tubular 405, and integrity of the seals is preserved. - While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
Claims (21)
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US17/145,137 US11396786B1 (en) | 2021-01-08 | 2021-01-08 | Wiper plug |
AU2021418131A AU2021418131A1 (en) | 2021-01-08 | 2021-12-08 | Wiper plug |
MX2023006818A MX2023006818A (en) | 2021-01-08 | 2021-12-08 | Wiper plug. |
EP21839016.9A EP4274948A1 (en) | 2021-01-08 | 2021-12-08 | Wiper plug |
CA3201744A CA3201744A1 (en) | 2021-01-08 | 2021-12-08 | Wiper plug |
PCT/EP2021/084761 WO2022148589A1 (en) | 2021-01-08 | 2021-12-08 | Wiper plug |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US17/145,137 US11396786B1 (en) | 2021-01-08 | 2021-01-08 | Wiper plug |
Publications (2)
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US20220220821A1 true US20220220821A1 (en) | 2022-07-14 |
US11396786B1 US11396786B1 (en) | 2022-07-26 |
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Family Applications (1)
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US17/145,137 Active US11396786B1 (en) | 2021-01-08 | 2021-01-08 | Wiper plug |
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US (1) | US11396786B1 (en) |
EP (1) | EP4274948A1 (en) |
AU (1) | AU2021418131A1 (en) |
CA (1) | CA3201744A1 (en) |
MX (1) | MX2023006818A (en) |
WO (1) | WO2022148589A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20230175344A1 (en) * | 2021-12-06 | 2023-06-08 | Canadian Casing Accessories Inc. | Modified cement plug and methods of use |
US20240117705A1 (en) * | 2022-10-10 | 2024-04-11 | Canadian Casing Accessories Inc. | Cement plug and methods of use |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3796260A (en) * | 1972-01-10 | 1974-03-12 | Halliburton Co | Multiple plug release system |
US4671358A (en) * | 1985-12-18 | 1987-06-09 | Mwl Tool Company | Wiper plug cementing system and method of use thereof |
US4854386A (en) * | 1988-08-01 | 1989-08-08 | Texas Iron Works, Inc. | Method and apparatus for stage cementing a liner in a well bore having a casing |
US20040065435A1 (en) * | 2002-10-02 | 2004-04-08 | Tessier Lynn P. | Self-anchoring cementing wiper plug |
US20190128087A1 (en) * | 2016-05-16 | 2019-05-02 | Halliburton Energy Services, Inc. | Wiper dart with reinforced drive element |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6527057B2 (en) | 2001-03-27 | 2003-03-04 | Baker Hughes Incorporated | Wiper plug delivery apparatus |
US6491103B2 (en) | 2001-04-09 | 2002-12-10 | Jerry P. Allamon | System for running tubular members |
US6513590B2 (en) | 2001-04-09 | 2003-02-04 | Jerry P. Allamon | System for running tubular members |
US6945326B2 (en) | 2002-12-03 | 2005-09-20 | Mikolajczyk Raymond F | Non-rotating cement wiper plugs |
US6848511B1 (en) | 2002-12-06 | 2005-02-01 | Weatherford/Lamb, Inc. | Plug and ball seat assembly |
US7128154B2 (en) | 2003-01-30 | 2006-10-31 | Weatherford/Lamb, Inc. | Single-direction cementing plug |
US7096949B2 (en) | 2003-09-04 | 2006-08-29 | Msi Machineering Solutions Inc. | Wiper plug with packer |
US8201634B2 (en) | 2009-05-20 | 2012-06-19 | Baker Hughes Incorporated | Subsea cementing plug system with plug launching tool |
US9004173B2 (en) | 2011-05-10 | 2015-04-14 | Baker Hughes Incorporated | Cement wiper plug with size changing feature |
US9587466B2 (en) | 2014-09-16 | 2017-03-07 | Wild Well Control, Inc. | Cementing system for riserless abandonment operation |
EP3303758B1 (en) | 2015-05-26 | 2020-11-25 | Weatherford Technology Holdings, LLC | Multi-function dart |
US10648272B2 (en) | 2016-10-26 | 2020-05-12 | Weatherford Technology Holdings, Llc | Casing floatation system with latch-in-plugs |
US10132139B1 (en) | 2017-10-13 | 2018-11-20 | Gryphon Oilfield Solutions, Llc | Mid-string wiper plug and carrier |
US10260306B1 (en) | 2017-12-01 | 2019-04-16 | Gryphon Oilfield Solutions, Llc | Casing wiper plug system and method for operating the same |
-
2021
- 2021-01-08 US US17/145,137 patent/US11396786B1/en active Active
- 2021-12-08 WO PCT/EP2021/084761 patent/WO2022148589A1/en active Application Filing
- 2021-12-08 AU AU2021418131A patent/AU2021418131A1/en active Pending
- 2021-12-08 CA CA3201744A patent/CA3201744A1/en active Pending
- 2021-12-08 EP EP21839016.9A patent/EP4274948A1/en active Pending
- 2021-12-08 MX MX2023006818A patent/MX2023006818A/en unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3796260A (en) * | 1972-01-10 | 1974-03-12 | Halliburton Co | Multiple plug release system |
US4671358A (en) * | 1985-12-18 | 1987-06-09 | Mwl Tool Company | Wiper plug cementing system and method of use thereof |
US4854386A (en) * | 1988-08-01 | 1989-08-08 | Texas Iron Works, Inc. | Method and apparatus for stage cementing a liner in a well bore having a casing |
US20040065435A1 (en) * | 2002-10-02 | 2004-04-08 | Tessier Lynn P. | Self-anchoring cementing wiper plug |
US20190128087A1 (en) * | 2016-05-16 | 2019-05-02 | Halliburton Energy Services, Inc. | Wiper dart with reinforced drive element |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20230175344A1 (en) * | 2021-12-06 | 2023-06-08 | Canadian Casing Accessories Inc. | Modified cement plug and methods of use |
US20240117705A1 (en) * | 2022-10-10 | 2024-04-11 | Canadian Casing Accessories Inc. | Cement plug and methods of use |
Also Published As
Publication number | Publication date |
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CA3201744A1 (en) | 2022-07-14 |
WO2022148589A1 (en) | 2022-07-14 |
EP4274948A1 (en) | 2023-11-15 |
AU2021418131A1 (en) | 2023-06-29 |
US11396786B1 (en) | 2022-07-26 |
MX2023006818A (en) | 2023-08-25 |
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