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
  • 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
  • E21B29/06—Cutting windows, e.g. directional window cutters for whipstock operations
• • 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
  • E21B33/146—Stage cementing, i.e. discharging cement from casing at different levels

Definitions

• This invention relates to a method of closing a well in the ground. More particularly, it relates to a method of closing a well in the ground, the well being provided with casing.
• the invention also includes a device for practising the method.
• each pressure-bearing zone it is usual to place at least two independent barriers including a suitable plugging material which is arranged to seal the well. In some cases it is necessary to remove a section in the longitudinal
• the casing material is machined away by means of a hard-metal blade which is arranged on a pipe string.
• the pipe string is connected to a drilling vessel or an installation with the necessary drilling
• Chips from the machining must be transported up to the surface because the chips, which may be magnetic and may include relatively long chip coils, prevent tools from passing the portion if the chips are not removed. Machining the longitudinal portion away from the casing by means of the prior art may take several days and is a very expensive operation.
• the invention has for its object to remedy or reduce at least one of the drawbacks of the prior art .
• the curable mass present in the casing forms a plug.
• the plug is permanent and seals against the formation.
• a cutting tool is meant, in this connection, a tool which is arranged to make cuts through the pipe wall as opposed to machining tools which are arranged to remove pipe material by chipping.
• the method may include cutting the openings by means of a fluid jet.
• a fluid jet By using a fluid jet, the further induction of magnetic forces into the pipe wall pieces is avoided.
• the pipe wall pieces cut out may be allowed to fall down and remain in the well.
• the pipe wall pieces may be carried to the surface, for example by means of a magnet.
• the method may further include the preparatory actions of:
• the method may further include connecting the cutting tool to the surface by means of coiled tubing.
• the method thereby makes it possible for the well to be shut down without the use of a drilling rig.
• the method can be practised by means of a cutting tool for cutting the longitudinal portion of a casing, the cutting tool including a nozzle head rotatable around its
• the nozzle head being connected to coiled tubing, the coiled tubing extending to the surface, and the cutting tool being connected to the casing by means of an anchor.
• the anchor may be a fixed anchor or a rolling anchor and the cutting. tool may be provided with an actuator for moving the nozzle head axially.
• the actuator may be used for axial movement of the nozzle head during the cutting operation. If a rolling anchor is used, the coiled tubing can be moved axially in the well without the use of a separate actuator.
• the cutting head may be provided with a pendulum nozzle.
• the pendulum nozzle which is of a design known per se, is arranged to pivot the fluid jet while the nozzle head is kept stationary.
• the cutting tool may be provided with a change-over valve which is arranged to selectably connect a fluid flow to a desired nozzle.
• the fluid flow may be directed to a cutting nozzle during the cutting operation and then directed to a cleaning nozzle during a subsequent cleaning operation.
• the method and device according to the invention enable a considerable reduction in the time spent on closing petroleum wells while, at the same time, considerably simpler equipment may be used compared with the prior art . ;
• the invention thereby provides for a substantial reduction in costs
• Figure 1 shows schematically a well which has been prepared for a cutting operation according to the invention
• Figure 2 shows schematically a section, on a larger scale, of a cutting head
• Figure 3 shows a cutting pattern in the wall of the casing
• Figure 4 shows schematically, on a smaller scale, a well
• the reference numeral 1 indicates a petroleum well in a formation 2.
• An inner casing 4, a second-inner casing 6 and other casings 8 are cemented into a borehole 10 by means of a cementation mass 12.
• a seal 14 seals between the inner casing 4 and the second- inner casing 6.
• FIG 1 the well 1 is shown after preparatory work has been carried out, such as filling the lower portion of the inner casing 4 with filler 16, cutting the inner casing 4 and removing the upper portion, not shown, of the inner casing 4 from the well 1.
• Coiled tubing 18 with a cutting tool 20 fitted is in the well 1, the cutting tool 20 being positioned and held fixed in the second-inner casing 6 by means of an anchor 22.
• the cutting tool 20 includes a tool housing 24 with necessary components known per se, not shown, for controlling the cutting operation.
• An actuator 26 is arranged to move a rotatable nozzle head 28 in the longitudinal direction of the well 1.
• the nozzle head 28 includes a change-over valve 30 for selectably directing pressure fluid which is supplied via an actuator channel 32 from the coiled tubing 18 to a cutting nozzle 34 or a cleaning nozzle 36, see figure 2.
• the change-over valve 30 may be a so-called sequence valve which changes its position every time the fluid pressure is relieved.
• the cutting may be started by fluid containing abrasive material flowing to the cutting nozzle 34 at relatively high pressure via the coiled tubing 18 and the change-over valve 30.
• the nozzle head 28 is brought to move the cutting nozzle 34 along a predetermined path giving, for example, the cutting path 38 in the pipe wall 40 of the second-inner casing 6 so that an opening 42 is cut, see figures 3 and 4. After that, the desired number of openings 42 may be cut.
• the pipe wall pieces 44 that are formed may be given a suitable size.
• the openings 42 in the second-inner casing 6 may extend across a
• the part of the cementation mass 12 that may be behind the longitudinal portion 46 of the second-inner casing 6 is also removed via the openings 42 by means of fluid jets from the nozzles 34, 36 of the nozzle head 28.
• a curable mass is then filled into the second-inner casing 6.
• the mass flows through the openings 42 and in between the second-inner casing 6 and the formation 2. Thereby a plug is formed, closing the cross section of the borehole 40.
• the longitudinal portion 46 may be chosen in a location in which openings will have to be cut in two or more casings 6, 8, one outside another, to give access to the formation 2.

Landscapes

• Geology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Mining & Mineral Resources (AREA)
• Environmental & Geological Engineering (AREA)
• Fluid Mechanics (AREA)
• Physics & Mathematics (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Placing Or Removing Of Piles Or Sheet Piles, Or Accessories Thereof (AREA)
• Earth Drilling (AREA)
• Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
• Road Repair (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (6)

Cited By (4)

Families Citing this family (5)

Citations (5)

Family Cites Families (5)

• 2009
  • 2009-12-17 NO NO20093545A patent/NO20093545A1/no not_active Application Discontinuation
• 2010
  • 2010-12-14 EP EP10837944A patent/EP2513414A1/en not_active Withdrawn
  • 2010-12-14 WO PCT/NO2010/000459 patent/WO2011074981A1/en not_active Ceased
  • 2010-12-14 US US13/516,882 patent/US20120279706A1/en not_active Abandoned
  • 2010-12-14 BR BR112012014203A patent/BR112012014203A2/pt not_active Application Discontinuation
  • 2010-12-14 AU AU2010330957A patent/AU2010330957A1/en not_active Abandoned

Patent Citations (5)

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