US20180171749A1 - Millable bridge plug system - Google Patents
Millable bridge plug system Download PDFInfo
- Publication number
- US20180171749A1 US20180171749A1 US15/387,036 US201615387036A US2018171749A1 US 20180171749 A1 US20180171749 A1 US 20180171749A1 US 201615387036 A US201615387036 A US 201615387036A US 2018171749 A1 US2018171749 A1 US 2018171749A1
- Authority
- US
- United States
- Prior art keywords
- cap end
- slip
- bridge plug
- mandrel
- fit engagement
- 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.)
- Abandoned
Links
- 238000007789 sealing Methods 0.000 claims abstract description 55
- 238000003801 milling Methods 0.000 claims abstract description 21
- 230000000712 assembly Effects 0.000 claims abstract description 19
- 238000000429 assembly Methods 0.000 claims abstract description 19
- 230000000295 complement effect Effects 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 10
- 238000005553 drilling Methods 0.000 claims description 9
- 239000000463 material Substances 0.000 description 7
- 239000002131 composite material Substances 0.000 description 6
- 230000008901 benefit Effects 0.000 description 3
- 239000000470 constituent Substances 0.000 description 3
- 238000009434 installation Methods 0.000 description 3
- 230000015556 catabolic process Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 239000004760 aramid Substances 0.000 description 1
- 229920003235 aromatic polyamide Polymers 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000000153 supplemental effect Effects 0.000 description 1
- 238000003466 welding Methods 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
- E21B33/134—Bridging plugs
-
- 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
- E21B23/00—Apparatus for displacing, setting, locking, releasing or removing tools, packers or the like in boreholes or wells
- E21B23/01—Apparatus for displacing, setting, locking, releasing or removing tools, packers or the like in boreholes or wells for anchoring the tools or the like
-
- 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
- E21B29/00—Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
-
- 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
- E21B33/128—Packers; Plugs with a member expanded radially by axial pressure
-
- 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
- E21B33/129—Packers; Plugs with mechanical slips for hooking into the casing
- E21B33/1291—Packers; Plugs with mechanical slips for hooking into the casing anchor set by wedge or cam in combination with frictional effect, using so-called drag-blocks
- E21B33/1292—Packers; Plugs with mechanical slips for hooking into the casing anchor set by wedge or cam in combination with frictional effect, using so-called drag-blocks with means for anchoring against downward and upward movement
-
- 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
- E21B33/129—Packers; Plugs with mechanical slips for hooking into the casing
- E21B33/1293—Packers; Plugs with mechanical slips for hooking into the casing with means for anchoring against downward and upward movement
Definitions
- the present invention relates to a downhole tool for isolating zones in a wellbore. More particularly, the present invention relates to a millable bridge plug system.
- a bridge plug is a downhole tool that is lowered into a wellbore. At a particular distance through the wellbore, the bridge plug is activated. The bridge plug opens and locks to seal the bridge plug to the walls of the wellbore. The bridge plug separates the wellbore into two sides. The upper portion can be cemented and tested, separate from the sealed lower portion of the wellbore. Sometimes the bridge plugs are permanent, and they seal an entire portion of the wellbore. Other times, the bridge plugs must be removed, and still other times, the bridge plugs must be removed and retrieved. These removable bridge plugs are millable or drillable, so that a drill string can grind through the bridge plug, making remnants of the destroyed bridge plug to remain at the bottom of a wellbore or to be retrieved to the surface by drilling mud flow.
- Bridge plugs generally include a mandrel, a sealing member placed around the mandrel, ring members adjacent the end of the sealing member and around the mandrel, upper and lower slip devices at opposite ends of the mandrel, and respective upper and lower cone assemblies engaged to the upper and lower slip devices.
- FIG. 1 shows the prior art bridge plug system 10 with a mandrel 12 , sealing member 14 , and upper and lower slip devices 16 and 18 shown.
- the bridge plug is placed in the wellbore by a setting tool on a positioning assembly, such as wireline, coiled tubing or even the drill string itself. Once in position at the correct depth and orientation, the bridge plug is activated.
- the setting tool holds the mandrel 12 in place, while a ramming portion of the setting tool exerts pressure on the stack, which includes the sealing member 14 and the slip devices 16 and 18 .
- the end 22 has a cap which prevents the stack from sliding off the mandrel 12 , when the ramming portion of the setting tool hits the stack. Instead, the pressure of the ramming portion compresses the stack, forcing the sealing member 14 to radially extend outward to seal against the wellbore or case and to flatten to a smaller height along the mandrel.
- the slip devices 16 are toothed and are distended radially outward by the stack to dig into the wellbore walls, locking the sealed configuration of the stack.
- FIG. 2 shows the prior art bridge plug system 10 in an activated and set state.
- Pressure on the lower cone assembly against the lower slip device 18 at the distal end of the mandrel causes the lower slip device 16 to open and latch against the wellbore.
- Pressure on the upper cone assembly causes the upper slip device 18 to also open and latch against the wellbore, setting the seal of the sealing member.
- a problem of the conventional bridge plug is the stabilization of the bridge plug during removal.
- a removal assembly such as a drill string or other wireline device, has a drill element to drill through a millable bridge plug, the bridge plug must be able to resist rotation of the drill element itself. Otherwise, a partially milled bridge plug could become lodged on the tip of the drill element of the removal assembly. These remnants of the bridge plug would be rotating along with the drill element of the removal assembly, so that these last remnants could avoid being destroyed and possibly hinder further action of the drill element on bridge plugs further down the wellbore.
- the structures of the bridge plug are not milled for removal under the same conditions.
- the upper slip device is milled, then the upper cone assembly, and then the sealing member, etc., as the drill element travels downward through the wellbore. Once the upper slip device is milled, the remaining elements are the remnants holding the bridge plug in place. Once the upper slip device and the upper cone assembly are milled, there are fewer remnants holding the bridge plug in place. As elements are removed, fewer and fewer elements resist the rotation of the drilling element. There is a need to improve the bridge plug to resist the rotation of the drill element, even as the number of remnants decreases.
- High temperatures are generally defined as downhole temperatures generally in the range of 200-450 degrees F.; and high pressures are generally defined as downhole pressures in the range of 7,500-15,000 psi.
- Other conditions include pH environments, generally ranging from less than 6.0 or more than 8.0.
- Conventional sealing elements have evolved to withstand these wellbore conditions so as to maintain effective seals and resist degradation.
- Metallic components have the durability to withstand the wellbore conditions, including high temperatures and high pressures. However, these metallic components are difficult to remove. De-activating and retrieving the bridge plug to the surface is costly and complicated. Milling metallic components takes time, and there is a substantial risk of requiring multiple drilling elements due to the metallic components wearing or damaging a drilling element of a removal assembly.
- Non-metallic components are substituted for metallic components as often as possible to avoid having so much metal to be milled for removal of the bridge plug. However, these non-metallic components still must effectively seal an annulus at high temperatures and high pressures.
- Composite materials are known to be used to make non-metallic components of the bridge plug. These composite materials combine constituent materials to form a composite material with physical properties of each composite material. For example, a polymer or epoxy can be reinforced by a continuous fiber such as glass, carbon, or aramid. The polymer is easily millable and withstands the wellbore conditions, while the fibers also withstand the wellbore conditions and resist degradation. Resin-coated glass is another known composite material with downhole tool applications. Composite materials have different constituent materials and different ways of combining constituent materials.
- Embodiments of the present invention include a millable bridge plug system with a mandrel, an upper cap end, a sealing means positioned around the mandrel, a plurality of ring members, a plurality of cone assemblies, a plurality of slip devices, and a lower cap end.
- the elements are mounted on the mandrel.
- the sealing means has an upper end and a lower end in the middle of the system.
- a first ring member is placed adjacent the upper end of the sealing means, and a second ring member is adjacent the lower end of the sealing means.
- a first cone assembly is proximate to the first ring member, and a second cone assembly is proximate to the second ring member.
- the slip means extend radially outward and engage an inner surface of a surrounding borehole to lock the position of the bridge plug.
- the upper cap end attaches to the mandrel and the first slip means, and the lower cap end attaches to the mandrel and the second slip means.
- the cap ends resist rotation of a removal assembly during a milling operation.
- Both the upper cap end and the lower cap end connect to the mandrel and respective slip means.
- the embodiments of the present invention relate to the lower cap end attached to the second slip means because the upper cap end and the first slip means are milled before other parts of the bridge plug system. Thus, these milled structures do not resist rotation of the system, even though they could in the beginning of the milling. As a practical matter, the lower cap end is a focus of the present application.
- Embodiments of the attachment of the lower cap end and the second slip means include the lower cap end being comprised of a male connector means, and the second slip means being comprised of a female connector means.
- the male-female connection is oriented so that the connectors face each other, when assembled.
- the male-female connection is a removable engagement, such that the lower cap end and the second slip means can be attached and removed, during assembly.
- the type of removable engagement includes slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
- the male connector means should have a shape complementary to a shape of the female connector means.
- the male-female connection also includes structures to prevent lateral movement between the lower cap end and the second slip means.
- Alternate embodiments include the male connector means as removable from the lower cap end.
- the protruding male connector can be mounted in the lower cap end as a separate piece or peg.
- the connectors are distributed along the perimeters of the lower cap end and the second slip means. These connectors can also be evenly distributed along the perimeter.
- the method of milling the bridge plug system include forming a bridge plug with the lower cap end attached to the mandrel and the second slip device, installing the bridge plug in a wellbore, and drilling with a removal assembly.
- the removal assembly mills the upper cap end, upper portion of the mandrel, the first slip device, the ring members, the sealing member, and the cone assemblies, while the second slip device, lower cap end, and lower portion of the mandrel hold position.
- the anchoring of the second slip device before milling stabilizes the system, while the system is being dismantled.
- FIG. 1 is a schematic view of a prior art bridge plug system, being placed in a wellbore.
- FIG. 2 is another schematic view of the prior art bridge plug system, being locked in position within the wellbore.
- FIG. 3 is a perspective view of an embodiment of the bridge plug of the present invention.
- FIG. 4 is an exploded perspective view of the embodiment of FIG. 3 .
- FIG. 5 is a cross-sectional view of an embodiment of the bridge plug of the present invention along an axis of the bridge plug, showing placement in the wellbore.
- FIG. 6 is a cross-sectional view of an embodiment of the bridge plug of the present invention along an axis of the bridge plug, showing an activated configuration in the wellbore.
- FIG. 7 is a perspective view of a slip device of an embodiment of the bridge plug of the present invention for one connector.
- FIG. 8 is an alternate perspective view of an embodiment of the slip device according to FIG. 7 .
- FIG. 9 is a perspective view of an embodiment of the lower cap end of FIGS. 3 and 4 , showing more than one connector.
- the system 100 includes a mandrel 112 , an upper cap end 128 , a sealing means 114 , and a plurality of ring members, 116 , 118 , a plurality of cone assemblies 120 , 122 , a plurality of slip means 124 , 126 , and a lower cap end 130 .
- the sealing means 114 , ring members 116 , 118 , cone assemblies 120 , 122 and the slip means 124 , 126 are stack structures mounted on the mandrel 112 , sharing a common radial axis of alignment.
- the millable bridge plug system 100 is placed within a wellbore or borehole of a well by a setting tool.
- the wellbore or the borehole could have a casing or not, and the orientation of the wellbore is variable.
- FIG. 5 shows an embodiment with a casing 132 .
- the bridge plug system 100 can be used in all ranges from generally vertical to generally horizontal orientations.
- the millable bridge plug system 100 is used to isolate zones within the wellbore, separating sections of the wellbore for production or isolation.
- the system 100 is millable or drillable, such that a removal assembly, such as a drill string, can be used to grind through the system 100 . All of the components of the system 100 are destroyed so that the isolated zone of the wellbore is removed.
- the mandrel 112 of the system 100 is a generally tubular member formed of a material to withstand the heat and pressure of the borehole conditions.
- the mandrel 112 is also millable.
- the mandrel 112 may have a bridge 134 , which seals the zone above the system 100 from the zone below the system 100 .
- the sealing means 114 is positioned around the mandrel 112 .
- the sealing means 114 has an upper end 136 and lower end 138 as shown in FIGS. 5 and 6 .
- the sealing means 114 is generally symmetrical to start and is comprised of a deformable material.
- FIGS. 3-6 also show the plurality of ring members, 116 , 118 .
- the ring members 116 , 118 surround the sealing means 114 and surround the mandrel 112 .
- the ring members 116 , 118 contact the sealing means 114 and can exert pressure on the sealing means 114 .
- the system 100 has the sealing means 114 compressed to radially extend to contact the wellbore or casing 132 .
- the ring members 116 , 118 directly contact the sealing means 114 .
- the seal created by the sealing means 114 isolates the zones on the wellbore. In combination with the bridge 130 in the mandrel 112 , the wellbore is separated.
- the system 100 also includes the plurality of cone assemblies, 120 , 122 .
- FIGS. 3-6 show a first cone assembly 120 proximate to the first ring member 116 and a second cone assembly 122 proximate to the second ring member 118 .
- the first ring member 116 is mounted on the mandrel 112 between the first cone assembly 120 and the sealing means 114 .
- the second ring member 118 is mounted on the mandrel 112 between the second cone assembly 122 and the sealing means 114 .
- the cone assemblies 120 , 122 contact the ring members 116 , 118 and can exert pressure on the ring members 116 , 18 .
- the system 100 has pressure of the cone assemblies 120 , 122 pushing through the ring members 116 , 118 to the sealing means 114 .
- FIGS. 3-6 also show the plurality of slip means 124 , 126 for extending radially outward and engaging an inner surface of a surrounding borehole.
- the slip means 124 , 126 lock the position of the system 100 by fixedly engaging the casing 132 or other structure on the inner surface of the borehole.
- the slips dig into the casing 132 to anchor the millable bridge plug system 100 .
- Pressure can be exerted on the system 100 to create the seal with the sealing means 114 , once the slip means 124 , 126 are active or while the slip means 124 , 126 are being activated.
- first slip means 124 mounted around the mandrel 112 and engaging the first cone assembly 120 and a second slip means 126 mounted around the mandrel 112 and engaging the second cone assembly 122 .
- the present invention may include further stack structures, such as cone seats or other supplemental ring members. Embodiments of the present invention relate to the structures and interactions between particularly defined stack structures to properly control the force exerted by the setting tool during installation.
- FIGS. 7-9 show detailed views of embodiments of the attachment of the lower cap end 130 and the second slip means 126 .
- FIGS. 7 and 8 show alternate perspective views of the second slip means 126 for one male-female connection. The male-female connection is shown in FIGS. 3, 4 and 7-8 .
- the second slip means 126 is stacked on the mandrel 112 .
- the mandrel 112 aligns all of the elements onto a single axis.
- the mandrel 112 inserts through the second slip means 126 . As shown in FIGS.
- the mandrel 112 attaches to the lower cap end 130 with a portion 194 engaging the body of the mandrel 112 in the stacking formation of the other element.
- the fixed engagement can be screw-fit engagement with complementary threaded ends locking together between the lower portion of the mandrel 112 and the lower cap end 130 .
- the fixed engagement can be friction fit or even welding or adhesives to make the lower cap end 130 integral with the lower portion of the mandrel 112 .
- the fixed engagement between the mandrel 112 and the lower cap end 130 does not permit rotation of the mandrel 112 relative to the lower cap end 130 .
- FIG. 9 does not show the mandrel 112 to lower cap end 130 fixed engagement because the connection is internal to the lower cap end 130 , consistent with FIGS. 5 and 6 .
- FIG. 8 shows more than one male-female connection.
- FIGS. 3-6 also show the lower cap end 130 attaching to the second slip means 126 on a side opposite from the second cone assembly 122 .
- the second slip means 126 is sandwiched between the second cone assembly 122 and the lower cap end 130 .
- Embodiments of the second slip means 126 and lower cap end 130 are shown in FIGS. 7-9 .
- the second slip means 126 is comprised of a plurality of extendable blades 152 arranged around a cylindrical body 154 .
- the tips 156 of the blades face the second cone assembly 124 , as consistent with FIGS. 5 and 6 .
- the side 160 facing the lower cap end 130 is comprised of a female connector means 158 .
- the lower cap end 130 has a contact surface 162 facing the second slip means 126 .
- the contact surface 162 can be separate from the fixed engagement of the mandrel 112 , also consistent with FIGS. 5 and 6 .
- the lower cap end 130 is comprised of a male connector means 164 protruding from the contact surface 162 .
- the male-female connection is oriented so that the connectors 158 , 164 face each other, when assembled.
- the male-female connection can be a removable engagement, such that the lower cap end 130 and the second slip means 126 are separable and attachable, during assembly.
- Embodiments of the present invention include the removable engagement as slide-fit engagement, groove-fit engagement, friction-fit engagement, or snap-fit engagement.
- FIGS. 3-4 show a slide-fit engagement.
- FIGS. 7-9 also show a slide-fit engagement.
- the female connector means 158 is a slot
- the male connector means 164 is a protrusion. The protrusion slides into the slot during assembly. There is no rotational movement or lateral movement relative to each other between the second slip means 126 and the lower cap end 130 .
- the present invention also includes a male connector means 164 with any shape complementary to a shape of the female connector means 158 .
- FIGS. 3-4 and 7-9 show a rectangle; however, any suitable shape, such as rectangular or trapezoidal, could be complementary for whichever type of removable engagement.
- the shape selection can be specific between a particular set of second slip devices 126 and lower cap ends 130 or modular so that any second slip device 126 can lock to any lower cap end 130 .
- the lower cap end 130 and the second slip means 126 are both cylindrical, such that the shape of the male and female connector means 158 , 164 can be radially oriented or arranged around the circular perimeter of the respective side 160 and contact surface 162 .
- the wider portion of the shape sets the radial orientation. The wider portion faces toward the circular perimeter with the larger diameter, like truncated pie wedges for trapezoidal shapes.
- FIG. 9 show the male connector means 164 comprised of a locking shoulder 166 .
- the locking shoulder 166 is formed by a T-shape protrusion 172 of the male connector means 164 on the lower cap end 130 .
- the complementary T-slot 168 of the female connector means 158 is shown in FIG. 7 .
- the complementary T-slot 168 has a slot shoulder 170 engaging the locking shoulder 166 .
- FIGS. 3, 4 and 9 is a male connector means 164 comprised of a post 174 and a head 176 at an end of the post 174 .
- a basic T-shape is not the only embodiment of the present invention, but the T-shape is an illustrative example.
- the post 174 protrudes from the contact surface 162 of the lower cap end 130 toward the second slip means 126 .
- the relevant complementary shape is now the shape of the head 176 or shape of the post 174 and head 176 , depending upon the shape of the female connector means 158 .
- An alternate embodiment is a removable male connector means 164 .
- the male connector means 164 can be attached and removed from the contact surface 162 of the lower cap end 130 .
- the protruding male connector means 164 can be a separate piece or peg. In this embodiment, the shape remains complementary to the female connector means 158 .
- a head-post, T-shape, trapezoidal, or locking shoulders are embodiments of the removable male connector means 164 .
- the removable male connector means 164 can be an advantage in assembly of the system 100 , while preserving the relative locked rotational and lateral movement. Even as a separate element, the male connector means 164 is made integral with the lower cap end 130 through mechanical engagement, which is removable.
- the mechanical engagement of the male connector means 164 to lower cap end includes slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
- the male connector means 164 may be fit into the female connector means 158 of the second slip means 126 and a slot or groove or cavity on the lower cap end 130 .
- the male and female connector means 158 , 164 are distributed along the perimeters of the lower cap end 130 and the second slip means 126 .
- FIG. 9 shows more than one connector with both connectors evenly distributed around the lower cap end 130 .
- the male and female connector means 158 , 164 are arranged in rings or a circular perimeter of the lower cap end 130 and second slip means 126 .
- the male connector means is comprised of two protrusions
- the two protrusions are placed across from each other on the ring of lower cap end 130 .
- the three protrusions the three protrusions are placed 120 degrees from each other on the ring or perimeter.
- the distribution can be even along the ring.
- a particular side can be strengthened with more than one protrusion on a particular arc of the ring.
- FIGS. 3 and 4 show an alternate embodiment with the upper cap end 128 attached to the mandrel 112 and the first slip means 124 .
- the first slip means 124 is comprised of a plurality of extendable blades 178 arranged around a cylindrical body 180 .
- the tips 182 of the blades 178 face the first cone assembly 120 , as consistent with FIGS. 5 and 6 .
- the side 184 facing the upper cap end 128 is comprised of a female connector means 186 .
- the upper cap end 128 has a contact surface 188 facing the first slip means 124 .
- the upper cap end 128 attaches to the first slip means 124 analogous to the lower cap end 130 attaching to the second slip means 126 .
- the removable attachment includes slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement, for complementary shapes between the female connector means 190 of the first slip means 124 , and the male connector means 190 of the upper cap end 128 .
- the alternate embodiment provides additional stability against rotation of elements on the mandrel 112 and prevents lateral movement between the elements in the stack.
- the lock of the upper cap end 128 does not improve much of the milling operation because the upper cap end 128 is one of the first elements drilled by the removal assembly.
- the male-female connection has benefits during assembly and installation of the system.
- Embodiments of the present invention include the method of milling a bridge plug system 100 .
- the bridge plug system is formed by assembling the upper cap end 128 onto the upper portion of the mandrel 112 and inserting the mandrel 112 through the first slip device 124 , the first cone assembly 120 , the first ring member 116 , the seaing member 114 , the second ring member 118 , the second cone assembly 122 , the second slip means 126 , and the lower cap end 130 .
- the elements are stacked along the mandrel 112 .
- the lower cap end 130 is attached to both the second slip means 126 and the mandrel 112 .
- the attachment between the lower cap end 130 and the second slip means 126 is more than the stacking arrangement.
- the bridge plug system 100 is installed by placing the bridge plug system 100 in a wellbore, forming the seal on the wellbore, and locking the system 100 in position within the wellbore.
- the system 100 is lowered into the wellbore having inner walls, such as a casing, using a setting tool on a positioning assembly.
- the mandrel is held in place as the stack structures 114 , 116 , 118 , 120 , 122 , 124 , and 126 are hammered by a ram portion of the setting tool.
- Pressure on the bridge plug system 110 forms a seal, when the sealing means 114 is compressed to radially extend outward to seal against the inner walls of the borehole.
- the ring members 116 , 118 push the sealing means 114 to expand, and the cone assemblies 120 , 122 push the ring members 116 , 118 .
- the cone assemblies 120 , 122 also push the slip means 124 , 126 to extend radially outward to fixedly engage the inner walls, locking the system 100 in position within the wellbore. At least one slip means 124 , 126 is activated, so that stack structures are locked in the sealed position.
- the exerted pressure through the system 100 is controlled by the first means 140 and second means 142 on the sealing means 114 , and sometimes in conjunction with the first ring means 144 and the second ring means 146 on the ring members 116 , 118 .
- the method of milling the bridge plug system further includes drilling with a removal assembly through the bridge plug 100 .
- a drill on the removal assembly mills through the stacked elements in order from top to bottom, including the upper cap, the upper portion of the mandrel, the sealing member, the ring members, the cone assemblies, and the first slip device.
- the second slip device, the lower cap end, and the lower portion of the mandrel are held in position without rotation or lateral movement relative to each other.
- the removal assembly can more easily drill through the remnants of the bridge plug, when the remnants are prevented from rotating by the second slip means 126 .
- the improved milling happens until the second slip means 126 is milled itself.
- Embodiments of the method include the step of forming the bridge plug system 100 by attaching the lower cap end 130 to the second slip means 126 with a male-female connection.
- the lower cap end 130 is comprised of a male connector
- the second slip device 126 is comprised of a female connector.
- the step of forming is further comprised of attaching the female connector and the male connector in at least one engagement of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
- the shapes of the male and female connectors are complementary, and some embodiments have the male connector as removable from the lower cap end 130 .
- the step of forming may also include forming the male connector on the lower cap end 130 by slide-fit engagement, groove-fit engagement, friction-fit engagement, or snap-fit engagement of the male connector to the lower cap end 130 .
- the present invention provides an embodiment of a millable bridge plug system.
- the slip devices and cap ends are innovative with unique attachment elements to provide functionality beyond the prior art.
- the problem of milling remnants of a bridge plug has not been addressed by prior art systems.
- the embodiments of the present invention are an inventive solution for stabilizing remnants during this removal of the bridge plug by milling.
- the slip devices are in an anchored position when installed.
- the blades have engaged the borehole walls for fixed placement of the bridge plug.
- the stability of the installation of the bridge plug can be utilized, during milling of the bridge plug, when the structures of the present invention are incorporated into slip devices and cap ends.
- the resistance to rotational and lateral movement of an installed bridge plug becomes resistance to rotational and lateral movement of a partially destroyed bridge plug, during a milling operation to remove the bridge plug.
- the structures of the slip devices and cap ends of the present invention enable the resistance of the blades engaged in the borehole wall to be used throughout all of the stacked elements of the bridge plug, even as each element is being milled.
- the present invention prevents loose remnants from spinning on the drilling element of the removal assembly without being milled. These loose remnants can cause damage and hinder the removal assembly, when milling bridge plugs further down the wellbore.
- the present invention provides a cleaner and more complete milling operation of installed bridge plugs.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
Abstract
A millable bridge plug system includes a mandrel, an upper cap end, a sealing member, ring members, cone assemblies, slip devices and a lower cap end. The sealing member, ring members, cone assemblies and slip devices are positioned on and around the mandrel. Ring members abut against an upper end and a lower end of the sealing member. The other sides of the ring members abut against the cone assemblies, and the cone assemblies engage respective slip devices. The upper cap end attaches to the first slip device, and the lower cap end attaches to the second slip device. The lower cap end holds the mandrel and second slip device together to resist rotation during milling.
Description
- See Application Data Sheet.
- Not applicable.
- Not applicable.
- Not applicable.
- Not applicable.
- The present invention relates to a downhole tool for isolating zones in a wellbore. More particularly, the present invention relates to a millable bridge plug system.
- A bridge plug is a downhole tool that is lowered into a wellbore. At a particular distance through the wellbore, the bridge plug is activated. The bridge plug opens and locks to seal the bridge plug to the walls of the wellbore. The bridge plug separates the wellbore into two sides. The upper portion can be cemented and tested, separate from the sealed lower portion of the wellbore. Sometimes the bridge plugs are permanent, and they seal an entire portion of the wellbore. Other times, the bridge plugs must be removed, and still other times, the bridge plugs must be removed and retrieved. These removable bridge plugs are millable or drillable, so that a drill string can grind through the bridge plug, making remnants of the destroyed bridge plug to remain at the bottom of a wellbore or to be retrieved to the surface by drilling mud flow.
- Bridge plugs generally include a mandrel, a sealing member placed around the mandrel, ring members adjacent the end of the sealing member and around the mandrel, upper and lower slip devices at opposite ends of the mandrel, and respective upper and lower cone assemblies engaged to the upper and lower slip devices.
FIG. 1 shows the prior artbridge plug system 10 with amandrel 12, sealingmember 14, and upper andlower slip devices mandrel 12 in place, while a ramming portion of the setting tool exerts pressure on the stack, which includes the sealingmember 14 and theslip devices mandrel 12, when the ramming portion of the setting tool hits the stack. Instead, the pressure of the ramming portion compresses the stack, forcing the sealingmember 14 to radially extend outward to seal against the wellbore or case and to flatten to a smaller height along the mandrel. Theslip devices 16 are toothed and are distended radially outward by the stack to dig into the wellbore walls, locking the sealed configuration of the stack. Thelower slip device 18 holds position by the cap at the end 22, while theupper slip device 16 lowers and locks the seal of the spreadsealing member 14. When the ramming portion has compressed and locked the stack, theend 20 proximal to the setting tool on the positioning assembly is sheared, separating the bridge plug from the setting tool and the positioning assembly.FIG. 2 shows the prior artbridge plug system 10 in an activated and set state. Pressure on the lower cone assembly against thelower slip device 18 at the distal end of the mandrel causes thelower slip device 16 to open and latch against the wellbore. Continuing pressure by the ram expands the sealingmember 14 against the rings to form a seal against the walls of the wellbore. Pressure on the upper cone assembly causes theupper slip device 18 to also open and latch against the wellbore, setting the seal of the sealing member. - A problem of the conventional bridge plug is the stabilization of the bridge plug during removal. A removal assembly, such as a drill string or other wireline device, has a drill element to drill through a millable bridge plug, the bridge plug must be able to resist rotation of the drill element itself. Otherwise, a partially milled bridge plug could become lodged on the tip of the drill element of the removal assembly. These remnants of the bridge plug would be rotating along with the drill element of the removal assembly, so that these last remnants could avoid being destroyed and possibly hinder further action of the drill element on bridge plugs further down the wellbore. The structures of the bridge plug are not milled for removal under the same conditions. The upper slip device is milled, then the upper cone assembly, and then the sealing member, etc., as the drill element travels downward through the wellbore. Once the upper slip device is milled, the remaining elements are the remnants holding the bridge plug in place. Once the upper slip device and the upper cone assembly are milled, there are fewer remnants holding the bridge plug in place. As elements are removed, fewer and fewer elements resist the rotation of the drilling element. There is a need to improve the bridge plug to resist the rotation of the drill element, even as the number of remnants decreases.
- Conventional materials of the millable bridge plug, like all downhole tools, must withstand the range of wellbore conditions, including high temperatures and/or high pressures. High temperatures are generally defined as downhole temperatures generally in the range of 200-450 degrees F.; and high pressures are generally defined as downhole pressures in the range of 7,500-15,000 psi. Other conditions include pH environments, generally ranging from less than 6.0 or more than 8.0. Conventional sealing elements have evolved to withstand these wellbore conditions so as to maintain effective seals and resist degradation.
- Metallic components have the durability to withstand the wellbore conditions, including high temperatures and high pressures. However, these metallic components are difficult to remove. De-activating and retrieving the bridge plug to the surface is costly and complicated. Milling metallic components takes time, and there is a substantial risk of requiring multiple drilling elements due to the metallic components wearing or damaging a drilling element of a removal assembly.
- Non-metallic components are substituted for metallic components as often as possible to avoid having so much metal to be milled for removal of the bridge plug. However, these non-metallic components still must effectively seal an annulus at high temperatures and high pressures. Composite materials are known to be used to make non-metallic components of the bridge plug. These composite materials combine constituent materials to form a composite material with physical properties of each composite material. For example, a polymer or epoxy can be reinforced by a continuous fiber such as glass, carbon, or aramid. The polymer is easily millable and withstands the wellbore conditions, while the fibers also withstand the wellbore conditions and resist degradation. Resin-coated glass is another known composite material with downhole tool applications. Composite materials have different constituent materials and different ways of combining constituent materials.
- It is an object of the present invention to provide an embodiment of the millable bridge plug system.
- It is another object of the present invention to provide an embodiment of the millable bridge plug system with improved slip devices and cap ends.
- It is another object of the present invention to provide an embodiment of the millable bridge plug system with improved slip devices to resist rotation of a drilling element of a removal assembly.
- It is still another object of the present invention to provide an embodiment of the millable bridge plug system with slip devices having attachments to respective end caps to resist rotation.
- It is yet another object of the present invention to provide an embodiment of the millable bridge plug system with slip devices engaged to respective end caps to resist rotation, when the bridge plug system is milled for removal.
- These and other objectives and advantages of the present invention will become apparent from a reading of the attached specifications and appended claims.
- Embodiments of the present invention include a millable bridge plug system with a mandrel, an upper cap end, a sealing means positioned around the mandrel, a plurality of ring members, a plurality of cone assemblies, a plurality of slip devices, and a lower cap end. The elements are mounted on the mandrel. The sealing means has an upper end and a lower end in the middle of the system. A first ring member is placed adjacent the upper end of the sealing means, and a second ring member is adjacent the lower end of the sealing means. A first cone assembly is proximate to the first ring member, and a second cone assembly is proximate to the second ring member. The slip means extend radially outward and engage an inner surface of a surrounding borehole to lock the position of the bridge plug. The upper cap end attaches to the mandrel and the first slip means, and the lower cap end attaches to the mandrel and the second slip means. The cap ends resist rotation of a removal assembly during a milling operation.
- Both the upper cap end and the lower cap end connect to the mandrel and respective slip means. The embodiments of the present invention relate to the lower cap end attached to the second slip means because the upper cap end and the first slip means are milled before other parts of the bridge plug system. Thus, these milled structures do not resist rotation of the system, even though they could in the beginning of the milling. As a practical matter, the lower cap end is a focus of the present application.
- Embodiments of the attachment of the lower cap end and the second slip means include the lower cap end being comprised of a male connector means, and the second slip means being comprised of a female connector means. The male-female connection is oriented so that the connectors face each other, when assembled. The male-female connection is a removable engagement, such that the lower cap end and the second slip means can be attached and removed, during assembly. The type of removable engagement includes slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement. The male connector means should have a shape complementary to a shape of the female connector means. The male-female connection also includes structures to prevent lateral movement between the lower cap end and the second slip means.
- Alternate embodiments include the male connector means as removable from the lower cap end. The protruding male connector can be mounted in the lower cap end as a separate piece or peg. In versions with more than one connector, the connectors are distributed along the perimeters of the lower cap end and the second slip means. These connectors can also be evenly distributed along the perimeter.
- The method of milling the bridge plug system, according to embodiments of the present invention, include forming a bridge plug with the lower cap end attached to the mandrel and the second slip device, installing the bridge plug in a wellbore, and drilling with a removal assembly. The removal assembly mills the upper cap end, upper portion of the mandrel, the first slip device, the ring members, the sealing member, and the cone assemblies, while the second slip device, lower cap end, and lower portion of the mandrel hold position. The anchoring of the second slip device before milling stabilizes the system, while the system is being dismantled.
-
FIG. 1 is a schematic view of a prior art bridge plug system, being placed in a wellbore. -
FIG. 2 is another schematic view of the prior art bridge plug system, being locked in position within the wellbore. -
FIG. 3 is a perspective view of an embodiment of the bridge plug of the present invention. -
FIG. 4 is an exploded perspective view of the embodiment ofFIG. 3 . -
FIG. 5 is a cross-sectional view of an embodiment of the bridge plug of the present invention along an axis of the bridge plug, showing placement in the wellbore. -
FIG. 6 is a cross-sectional view of an embodiment of the bridge plug of the present invention along an axis of the bridge plug, showing an activated configuration in the wellbore. -
FIG. 7 is a perspective view of a slip device of an embodiment of the bridge plug of the present invention for one connector. -
FIG. 8 is an alternate perspective view of an embodiment of the slip device according toFIG. 7 . -
FIG. 9 is a perspective view of an embodiment of the lower cap end ofFIGS. 3 and 4 , showing more than one connector. - Referring to
FIGS. 3-6 , an embodiment of the millablebridge plug system 100 of the present invention is shown. Thesystem 100 includes amandrel 112, anupper cap end 128, a sealing means 114, and a plurality of ring members, 116, 118, a plurality ofcone assemblies lower cap end 130. The sealing means 114,ring members cone assemblies mandrel 112, sharing a common radial axis of alignment.FIGS. 3-6 also show anupper cap end 128 and alower cap end 130. The millablebridge plug system 100 is placed within a wellbore or borehole of a well by a setting tool. The wellbore or the borehole could have a casing or not, and the orientation of the wellbore is variable.FIG. 5 shows an embodiment with acasing 132. Thebridge plug system 100 can be used in all ranges from generally vertical to generally horizontal orientations. As previously described, the millablebridge plug system 100 is used to isolate zones within the wellbore, separating sections of the wellbore for production or isolation. Thesystem 100 is millable or drillable, such that a removal assembly, such as a drill string, can be used to grind through thesystem 100. All of the components of thesystem 100 are destroyed so that the isolated zone of the wellbore is removed. - The
mandrel 112 of thesystem 100 is a generally tubular member formed of a material to withstand the heat and pressure of the borehole conditions. Themandrel 112 is also millable. Themandrel 112 may have abridge 134, which seals the zone above thesystem 100 from the zone below thesystem 100. The sealing means 114 is positioned around themandrel 112. The sealing means 114 has anupper end 136 andlower end 138 as shown inFIGS. 5 and 6 . The sealing means 114 is generally symmetrical to start and is comprised of a deformable material. -
FIGS. 3-6 also show the plurality of ring members, 116, 118. There is afirst ring member 116 adjacent theupper end 136 of the sealing means 114 and asecond ring member 118 adjacent thelower end 138 of the sealing means 114. Thering members mandrel 112. Thering members system 100 has the sealing means 114 compressed to radially extend to contact the wellbore orcasing 132. Thering members bridge 130 in themandrel 112, the wellbore is separated. - The
system 100 also includes the plurality of cone assemblies, 120, 122.FIGS. 3-6 show afirst cone assembly 120 proximate to thefirst ring member 116 and asecond cone assembly 122 proximate to thesecond ring member 118. As shown in exploded view ofFIG. 3 , thefirst ring member 116 is mounted on themandrel 112 between thefirst cone assembly 120 and the sealing means 114. Similarly, thesecond ring member 118 is mounted on themandrel 112 between thesecond cone assembly 122 and the sealing means 114. Thecone assemblies ring members ring members system 100 has pressure of thecone assemblies ring members -
FIGS. 3-6 also show the plurality of slip means 124, 126 for extending radially outward and engaging an inner surface of a surrounding borehole. The slip means 124, 126 lock the position of thesystem 100 by fixedly engaging thecasing 132 or other structure on the inner surface of the borehole. The slips dig into thecasing 132 to anchor the millablebridge plug system 100. Pressure can be exerted on thesystem 100 to create the seal with the sealing means 114, once the slip means 124, 126 are active or while the slip means 124, 126 are being activated. There is a first slip means 124 mounted around themandrel 112 and engaging thefirst cone assembly 120 and a second slip means 126 mounted around themandrel 112 and engaging thesecond cone assembly 122. The present invention may include further stack structures, such as cone seats or other supplemental ring members. Embodiments of the present invention relate to the structures and interactions between particularly defined stack structures to properly control the force exerted by the setting tool during installation. -
FIGS. 7-9 show detailed views of embodiments of the attachment of thelower cap end 130 and the second slip means 126.FIGS. 7 and 8 show alternate perspective views of the second slip means 126 for one male-female connection. The male-female connection is shown inFIGS. 3, 4 and 7-8 . Similar to the first slip means 124, the second slip means 126 is stacked on themandrel 112. Themandrel 112 aligns all of the elements onto a single axis. Themandrel 112 inserts through the second slip means 126. As shown inFIGS. 5-6 , themandrel 112 attaches to thelower cap end 130 with aportion 194 engaging the body of themandrel 112 in the stacking formation of the other element. In some embodiments, the fixed engagement can be screw-fit engagement with complementary threaded ends locking together between the lower portion of themandrel 112 and thelower cap end 130. The fixed engagement can be friction fit or even welding or adhesives to make thelower cap end 130 integral with the lower portion of themandrel 112. The fixed engagement between themandrel 112 and thelower cap end 130 does not permit rotation of themandrel 112 relative to thelower cap end 130.FIG. 9 does not show themandrel 112 tolower cap end 130 fixed engagement because the connection is internal to thelower cap end 130, consistent withFIGS. 5 and 6 . Also,FIG. 8 shows more than one male-female connection. -
FIGS. 3-6 also show thelower cap end 130 attaching to the second slip means 126 on a side opposite from thesecond cone assembly 122. The second slip means 126 is sandwiched between thesecond cone assembly 122 and thelower cap end 130. - Embodiments of the second slip means 126 and
lower cap end 130 are shown inFIGS. 7-9 . The second slip means 126 is comprised of a plurality ofextendable blades 152 arranged around acylindrical body 154. Thetips 156 of the blades face thesecond cone assembly 124, as consistent withFIGS. 5 and 6 . Theside 160 facing thelower cap end 130 is comprised of a female connector means 158. Thelower cap end 130 has acontact surface 162 facing the second slip means 126. Thecontact surface 162 can be separate from the fixed engagement of themandrel 112, also consistent withFIGS. 5 and 6 . Thelower cap end 130 is comprised of a male connector means 164 protruding from thecontact surface 162. The male-female connection is oriented so that theconnectors - The male-female connection can be a removable engagement, such that the
lower cap end 130 and the second slip means 126 are separable and attachable, during assembly. Embodiments of the present invention include the removable engagement as slide-fit engagement, groove-fit engagement, friction-fit engagement, or snap-fit engagement.FIGS. 3-4 show a slide-fit engagement.FIGS. 7-9 also show a slide-fit engagement. The female connector means 158 is a slot, and the male connector means 164 is a protrusion. The protrusion slides into the slot during assembly. There is no rotational movement or lateral movement relative to each other between the second slip means 126 and thelower cap end 130. - The present invention also includes a male connector means 164 with any shape complementary to a shape of the female connector means 158.
FIGS. 3-4 and 7-9 show a rectangle; however, any suitable shape, such as rectangular or trapezoidal, could be complementary for whichever type of removable engagement. The shape selection can be specific between a particular set ofsecond slip devices 126 and lower cap ends 130 or modular so that anysecond slip device 126 can lock to anylower cap end 130. Thelower cap end 130 and the second slip means 126 are both cylindrical, such that the shape of the male and female connector means 158, 164 can be radially oriented or arranged around the circular perimeter of therespective side 160 andcontact surface 162. In some embodiments, the wider portion of the shape sets the radial orientation. The wider portion faces toward the circular perimeter with the larger diameter, like truncated pie wedges for trapezoidal shapes. - Other embodiments, including the embodiment shown in
FIG. 9 , show the male connector means 164 comprised of a lockingshoulder 166. The lockingshoulder 166 is formed by a T-shape protrusion 172 of the male connector means 164 on thelower cap end 130. The complementary T-slot 168 of the female connector means 158 is shown inFIG. 7 . The complementary T-slot 168 has aslot shoulder 170 engaging the lockingshoulder 166. In this embodiment, there is no lateral movement between the second slip means 126 and thelower cap end 130. The rotational movement relative to each other is also prevented. - One embodiment shown in
FIGS. 3, 4 and 9 is a male connector means 164 comprised of apost 174 and ahead 176 at an end of thepost 174. A basic T-shape is not the only embodiment of the present invention, but the T-shape is an illustrative example. Thepost 174 protrudes from thecontact surface 162 of thelower cap end 130 toward the second slip means 126. The relevant complementary shape is now the shape of thehead 176 or shape of thepost 174 andhead 176, depending upon the shape of the female connector means 158. - An alternate embodiment is a removable male connector means 164. The male connector means 164 can be attached and removed from the
contact surface 162 of thelower cap end 130. The protruding male connector means 164 can be a separate piece or peg. In this embodiment, the shape remains complementary to the female connector means 158. A head-post, T-shape, trapezoidal, or locking shoulders are embodiments of the removable male connector means 164. The removable male connector means 164 can be an advantage in assembly of thesystem 100, while preserving the relative locked rotational and lateral movement. Even as a separate element, the male connector means 164 is made integral with thelower cap end 130 through mechanical engagement, which is removable. The mechanical engagement of the male connector means 164 to lower cap end includes slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement. The male connector means 164 may be fit into the female connector means 158 of the second slip means 126 and a slot or groove or cavity on thelower cap end 130. - In embodiments with more than one connector, the male and female connector means 158, 164 are distributed along the perimeters of the
lower cap end 130 and the second slip means 126.FIG. 9 shows more than one connector with both connectors evenly distributed around thelower cap end 130. With thelower cap end 130 and second slip means 126 being generally cylindrical, the male and female connector means 158, 164 are arranged in rings or a circular perimeter of thelower cap end 130 and second slip means 126. For example, when the male connector means is comprised of two protrusions, then the two protrusions are placed across from each other on the ring oflower cap end 130. With three protrusions, the three protrusions are placed 120 degrees from each other on the ring or perimeter. The distribution can be even along the ring. In other embodiments, a particular side can be strengthened with more than one protrusion on a particular arc of the ring. -
FIGS. 3 and 4 show an alternate embodiment with theupper cap end 128 attached to themandrel 112 and the first slip means 124. The first slip means 124 is comprised of a plurality ofextendable blades 178 arranged around a cylindrical body 180. Thetips 182 of theblades 178 face thefirst cone assembly 120, as consistent withFIGS. 5 and 6 . The side 184 facing theupper cap end 128 is comprised of a female connector means 186. Theupper cap end 128 has acontact surface 188 facing the first slip means 124. - In the alternate embodiment of
FIGS. 3 and 4 , theupper cap end 128 attaches to the first slip means 124 analogous to thelower cap end 130 attaching to the second slip means 126. There can be a female connector means 186 in the first slip means 124 and a male connector means 190 on theupper cap end 128. The removable attachment includes slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement, for complementary shapes between the female connector means 190 of the first slip means 124, and the male connector means 190 of theupper cap end 128. The alternate embodiment provides additional stability against rotation of elements on themandrel 112 and prevents lateral movement between the elements in the stack. The lock of theupper cap end 128 does not improve much of the milling operation because theupper cap end 128 is one of the first elements drilled by the removal assembly. However, the male-female connection has benefits during assembly and installation of the system. - Embodiments of the present invention include the method of milling a
bridge plug system 100. The bridge plug system is formed by assembling theupper cap end 128 onto the upper portion of themandrel 112 and inserting themandrel 112 through thefirst slip device 124, thefirst cone assembly 120, thefirst ring member 116, theseaing member 114, thesecond ring member 118, thesecond cone assembly 122, the second slip means 126, and thelower cap end 130. The elements are stacked along themandrel 112. Thelower cap end 130 is attached to both the second slip means 126 and themandrel 112. The attachment between thelower cap end 130 and the second slip means 126 is more than the stacking arrangement. Then, thebridge plug system 100 is installed by placing thebridge plug system 100 in a wellbore, forming the seal on the wellbore, and locking thesystem 100 in position within the wellbore. - In some embodiments, the
system 100 is lowered into the wellbore having inner walls, such as a casing, using a setting tool on a positioning assembly. The mandrel is held in place as thestack structures ring members cone assemblies ring members cone assemblies system 100 in position within the wellbore. At least one slip means 124, 126 is activated, so that stack structures are locked in the sealed position. The exerted pressure through thesystem 100 is controlled by the first means 140 and second means 142 on the sealing means 114, and sometimes in conjunction with the first ring means 144 and the second ring means 146 on thering members - The method of milling the bridge plug system further includes drilling with a removal assembly through the
bridge plug 100. When thebridge plug 100 has served its purpose and requires removal, a drill on the removal assembly mills through the stacked elements in order from top to bottom, including the upper cap, the upper portion of the mandrel, the sealing member, the ring members, the cone assemblies, and the first slip device. In the present invention, the second slip device, the lower cap end, and the lower portion of the mandrel are held in position without rotation or lateral movement relative to each other. The removal assembly can more easily drill through the remnants of the bridge plug, when the remnants are prevented from rotating by the second slip means 126. The improved milling happens until the second slip means 126 is milled itself. - Embodiments of the method include the step of forming the
bridge plug system 100 by attaching thelower cap end 130 to the second slip means 126 with a male-female connection. Thelower cap end 130 is comprised of a male connector, and thesecond slip device 126 is comprised of a female connector. The step of forming is further comprised of attaching the female connector and the male connector in at least one engagement of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement. In embodiments of the invention, the shapes of the male and female connectors are complementary, and some embodiments have the male connector as removable from thelower cap end 130. The step of forming may also include forming the male connector on thelower cap end 130 by slide-fit engagement, groove-fit engagement, friction-fit engagement, or snap-fit engagement of the male connector to thelower cap end 130. - The present invention provides an embodiment of a millable bridge plug system. The slip devices and cap ends are innovative with unique attachment elements to provide functionality beyond the prior art. The problem of milling remnants of a bridge plug has not been addressed by prior art systems. The embodiments of the present invention are an inventive solution for stabilizing remnants during this removal of the bridge plug by milling. The slip devices are in an anchored position when installed. The blades have engaged the borehole walls for fixed placement of the bridge plug. The stability of the installation of the bridge plug can be utilized, during milling of the bridge plug, when the structures of the present invention are incorporated into slip devices and cap ends. The resistance to rotational and lateral movement of an installed bridge plug becomes resistance to rotational and lateral movement of a partially destroyed bridge plug, during a milling operation to remove the bridge plug. The structures of the slip devices and cap ends of the present invention enable the resistance of the blades engaged in the borehole wall to be used throughout all of the stacked elements of the bridge plug, even as each element is being milled. The present invention prevents loose remnants from spinning on the drilling element of the removal assembly without being milled. These loose remnants can cause damage and hinder the removal assembly, when milling bridge plugs further down the wellbore. The present invention provides a cleaner and more complete milling operation of installed bridge plugs.
- The foregoing disclosure and description of the invention is illustrative and explanatory thereof. Various changes in the details of the illustrated structures, construction and method can be made without departing from the true spirit of the invention.
Claims (20)
1. A millable bridge plug system, comprising:
a mandrel having an upper portion and a lower portion;
an upper cap end attached at said upper portion of said mandrel;
a sealing means positioned around the mandrel between said upper portion and said lower portion;
a plurality of ring members, a first ring member adjacent an upper end of said sealing means and a second ring member adjacent a lower end of said sealing means;
a plurality of cone assemblies, a first cone assembly proximate to said first ring member and a second cone assembly proximate to said second ring member, said first ring member being between said first cone assembly and said sealing means, said second ring member being between said second cone assembly and said sealing means;
a plurality of slip means for extending radially outward and engaging an inner surface of a surrounding borehole, a first slip means mounted around said mandrel and engaging said first cone assembly and a second slip means mounted around said mandrel and engaging said second cone assembly; and
a lower cap end attached at said lower portion of said mandrel,
wherein said upper cap end attaches to said first slip means on a side opposite from said first cone assembly, and wherein said lower cap end attaches to said second slip means on a side opposite from said second cone assembly.
2. The bridge plug system according to claim 1 , wherein said lower cap end is comprised of a male connector means, and wherein said second slip means is comprised of a female connector means, said female connector and said male connector means attaching said lower cap end to said second slip means.
3. The bridge plug system according to claim 2 , wherein said female connector means and said male connector means attach in at least one engagement of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
4. The bridge plug system according to claim 2 , wherein said male connector means has a shape complementary to a shape of said female connector means.
5. The bridge plug system according to claim 4 , wherein said shape of said male connector means is at least one of a group consisting of: rectangular and trapezoidal.
6. The bridge plug system according to claim 4 , wherein said shape of said male connector means has a wider portion oriented radially towards an outer surface of said lower cap end.
7. The bridge plug system according to claim 4 , wherein said shape of said male connector means forms a locking shoulder abutted against said shape of said female connector means, so as to prevent lateral movement between said second slip means and said lower cap end.
8. The bridge plug system according to claim 2 , wherein said male connector means is comprised of a post and a head at an end of said post, said post protruding from an end surface of said second slip means toward said lower cap end, said head having a shape corresponding to a shape of said female connector means.
9. The bridge plug system according to claim 8 , wherein said post is comprised of a slot on said end surface of said lower cap end and a connector member, wherein said head is positioned at an end of said connector member, said connector member being removably engaged to said slot, said connector member protruding from said slot in said end surface of said lower cap end toward said second slip means, said head having a shape corresponding to a shape of said female connector means.
10. The bridge plug system according to claim 9 , wherein said connector member and said slot being in removable engagement according to at least one of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
11. The bridge plug system according to claim 8 , wherein said post and head form a locking shoulder, said locking shoulder abutting against said shape of said female connector means, so as to prevent lateral movement between said second slip means and said lower cap end.
12. The bridge plug system according to claim 1 , wherein said lower cap end is comprised of a male connector means arranged around a perimeter of said lower cap end, and wherein said second slip means is comprised of a female connector means arranged around a perimeter of said second slip means, said female connector and said male connector means being aligned around respective perimeters to attach said lower cap end to said second slip means.
13. The bridge plug system according to claim 12 , wherein said female connector means and said male connector means are distributed evenly and correspondingly around respective perimeters.
14. A millable bridge plug system comprising:
a mandrel having an upper portion and a lower portion;
an upper cap end attached at said upper portion of said mandrel;
a sealing means positioned around the mandrel between said upper portion and said lower portion;
a plurality of ring members, a first ring member adjacent an upper end of said sealing means and a second ring member adjacent a lower end of said sealing means;
a plurality of cone assemblies, a first cone assembly proximate to said first ring member and a second cone assembly proximate to said second ring member, said first ring member being between said first cone assembly and said sealing means, said second ring member being between said second cone assembly and said sealing means;
a plurality of slip means for extending radially outward and engaging an inner surface of a surrounding borehole, a first slip means mounted around said mandrel and engaging said first cone assembly and a second slip means mounted around said mandrel and engaging said second cone assembly; and
a lower cap end attached at said lower portion of said mandrel,
wherein said upper cap end attaches to said first slip means on a side opposite from said first cone assembly,
wherein said lower cap end attaches to said second slip means on a side opposite from said second cone assembly,
wherein said lower cap end is comprised of a first male connector means, and wherein said second slip means is comprised of a first female connector means, said first female connector and said first male connector means attaching said lower cap end to said second slip means, and
wherein said upper cap end is comprised of a second male connector means, and wherein said first slip means is comprised of a second female connector means, said second female connector and said second male connector means attaching said upper cap end to said first slip means.
15. The bridge plug system according to claim 14 , wherein said first female connector means and said first male connector means attach in at least one of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement, and
wherein said second female connector means and said second male connector means attach in at least one of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
16. A method of milling a bridge plug system, comprising the steps of:
forming a bridge plug, said bridge plug comprising:
a mandrel having an upper portion and a lower portion;
an upper cap end attached at said upper portion of said mandrel;
a sealing member positioned around the mandrel between said upper portion and said lower portion;
a plurality of ring members, a first ring member adjacent an upper end of said sealing member and a second ring member adjacent a lower end of said sealing member;
a plurality of cone assemblies, a first cone assembly proximate to said first ring member and a second cone assembly proximate to said second ring member, said first ring member being between said first cone assembly and said sealing member, said second ring member being between said second cone assembly and said sealing member;
a plurality of slip devices for extending radially outward and engaging an inner surface of a surrounding borehole, a first slip device mounted around said mandrel and engaging said first cone assembly and a second slip device mounted around said mandrel and engaging said second cone assembly; and
a lower cap end attached at said lower portion of said mandrel and to said first slip device on a side opposite from said second cone assembly,
installing said bridge plug in a wellbore, said wellbore having inner walls surrounding said bridge plug;
drilling with a removal assembly through said bridge plug, said upper cap, said upper portion of said mandrel, said sealing member, said ring members, said cone assemblies, and said first slip device, while said second slip device, said lower cap end, and said lower portion of said mandrel are held in position.
17. The method of milling, according to claim 16 , wherein said lower cap end is comprised of a male connector, and wherein said second slip device is comprised of a female connector, said female connector and said male connector means attaching said lower cap end to said second slip device.
18. The method of milling, according to claim 17 , the step of forming said bridge plug comprising:
attaching said female connector and said male connector in at least one engagement of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
19. The method of milling, according to claim 18 , wherein said female connector and said male connector have complementary shapes.
20. The method of milling, according to claim 17 , the step of forming said bridge plug comprising:
setting said male connector in said lower cap end by removable engagement of at least one of a group consisting of: slide-fit engagement, groove-fit engagement, friction-fit engagement, and snap-fit engagement.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/387,036 US20180171749A1 (en) | 2016-12-21 | 2016-12-21 | Millable bridge plug system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/387,036 US20180171749A1 (en) | 2016-12-21 | 2016-12-21 | Millable bridge plug system |
Publications (1)
Publication Number | Publication Date |
---|---|
US20180171749A1 true US20180171749A1 (en) | 2018-06-21 |
Family
ID=62556866
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/387,036 Abandoned US20180171749A1 (en) | 2016-12-21 | 2016-12-21 | Millable bridge plug system |
Country Status (1)
Country | Link |
---|---|
US (1) | US20180171749A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109723930A (en) * | 2019-01-21 | 2019-05-07 | 陈黎祥 | The solvable bridge plugging tool of Fast Installation and method for blocking |
WO2020131118A1 (en) * | 2018-12-21 | 2020-06-25 | Halliburton Energy Services, Inc. | A through tubing bridge plug having high expansion elastomer design |
US11028666B2 (en) * | 2019-11-07 | 2021-06-08 | Target Completions Llc | Apparatus for isolating one or more zones in a well |
US11299957B2 (en) * | 2018-08-30 | 2022-04-12 | Avalon Research Ltd. | Plug for a coiled tubing string |
US11555375B2 (en) * | 2019-10-07 | 2023-01-17 | Brad SCOGGINS | Composite cement retainer |
-
2016
- 2016-12-21 US US15/387,036 patent/US20180171749A1/en not_active Abandoned
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11299957B2 (en) * | 2018-08-30 | 2022-04-12 | Avalon Research Ltd. | Plug for a coiled tubing string |
WO2020131118A1 (en) * | 2018-12-21 | 2020-06-25 | Halliburton Energy Services, Inc. | A through tubing bridge plug having high expansion elastomer design |
US11105181B2 (en) | 2018-12-21 | 2021-08-31 | Halliburton Energy Services, Inc. | Through tubing bridge plug having high expansion elastomer design |
CN109723930A (en) * | 2019-01-21 | 2019-05-07 | 陈黎祥 | The solvable bridge plugging tool of Fast Installation and method for blocking |
US11555375B2 (en) * | 2019-10-07 | 2023-01-17 | Brad SCOGGINS | Composite cement retainer |
US20230123688A1 (en) * | 2019-10-07 | 2023-04-20 | Brad SCOGGINS | Composite Cement Retainer |
US11028666B2 (en) * | 2019-11-07 | 2021-06-08 | Target Completions Llc | Apparatus for isolating one or more zones in a well |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20180171749A1 (en) | Millable bridge plug system | |
US9121253B2 (en) | Millable bridge plug system | |
US20200217173A1 (en) | Downhole assembly for selectively sealing off a wellbore | |
US5924696A (en) | Frangible pressure seal | |
US9359861B2 (en) | Downhole packer tool with dummy slips | |
US7475736B2 (en) | Self centralizing non-rotational slip and cone system for downhole tools | |
US4127168A (en) | Well packers using metal to metal seals | |
US11180972B2 (en) | Downhole tool system and methods related thereto | |
US10822902B2 (en) | Retractable pump down ring | |
EP0143572A2 (en) | Well packer device | |
US9194209B2 (en) | Hydraulicaly fracturable downhole valve assembly and method for using same | |
US10450829B2 (en) | Drillable plug | |
US10465470B2 (en) | Radially expandable ratcheting body lock ring for production packer release | |
US7124827B2 (en) | Expandable whipstock anchor assembly | |
WO2004051049A2 (en) | Non-rotating cement wiper plugs | |
US6935428B2 (en) | Apparatus and methods for anchoring and orienting equipment in well casing | |
US11613740B2 (en) | Plug for oil field service work and method of production | |
US9121254B2 (en) | Millable bridge plug system | |
US11352540B2 (en) | Dissolvable fracking plug assembly | |
US20140174738A1 (en) | Millable bridge plug system | |
US10415345B2 (en) | Millable bridge plug system | |
US20190071949A1 (en) | Collapsible support rings for a downhole system | |
CN210918964U (en) | Downward oil pipe blowout preventer | |
US12065901B1 (en) | Expanding and collapsing apparatus having bookend seal cartridges | |
CA3224855A1 (en) | Slip ring employing radially offset slot |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: CNPC USA CORP., TEXAS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:YUE, JIANPENG;GREGORY, MARVIN;CHENG, PENG;AND OTHERS;SIGNING DATES FROM 20161003 TO 20161130;REEL/FRAME:041151/0864 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: FINAL REJECTION MAILED |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |