Patent EA-004283-B1 (EA)
Title: Device for performing a portion of casing in a reservoir
Inventor: BAKKE STIG
IPC: E21B43/112
Filed: 2001-06-22
Abstract: 1. A method of making holes in a pipe (26) in the production zone of a hydrocarbon-producing well and loosening/perforating externally located sedimentary rock (80), with the aim of favouring and improving the well in terms of production, wherein a tool (10) is used, which may be lowered into the well and hauled up therefrom, comprising an elongated tool housing (10a) of sleeve-shaped/tubular configuration along the major part of its length, where there is at least one drilling means (28) and at least one jetting means (42) and possibly at least one supporting holding-up means (32) in the inactive positions of said means, the tool housing (10a) being formed with a radial transverse opening for each means (28, 42, 32); and the drilling means (28) there are arranged a driving motor (30) for the supply of rotary energy required during drilling, and a driven, controlled moving mechanism (56,58,60,76,78) for moving the drilling means (28) between an inactive stand-by position within the outer mantle surface of the tool housing (10a), and an active drilling position, in which it is arranged, by activation of the driving motor (30), to drill its way through an adjacent pipe wall (26); and the jetting means (42) has the form of an elastically flexible jetting hose with an outer propulsion head, for example in the form of a nozzle head (42a) with pressure liquid supply, said jetting hose (42) having a feeding device (96) and guides/ control means (82, 102) arranged thereto, for moving the jetting hose (42) and transferring same from an inactive stand-by position within the outer wall of the tool housing (10a) into a moving position, in which it is moved radially outwards from the tool housing (10a), first through a hole (40) of the pipe wall (26) that the drilling means (28) has drilled, and then into the sediment (80) surrounding the pipe (26), characterized in that that the drilling means (28) opposite the drill bit, which is positioned at a radially outer end, is connected to a link arm system (56,58,60) driven by an axially reciprocating piston device (76,78) in order to provide - by the axially reciprocating displacing motion of the piston (76) in a cylinder (78) which is formed in the tool housing (10a) and has a longitudinal axis that coincides with the axis of the tool housing - a controlled transfer of the drilling means (28) between its active position and its inactive position and vice versa. 2. A tool as claimed claim 1, characterized in that the jetting hose (42) has a drum (86) arranged thereto for the winding/unwinding of the hose, and in connection therewith, a feeding body (96) reciprocatingly displaceable axially, said drum (86) having an axial axis of rotation and a double wall (86a,86b), the two concentric walls defining between themselves an annular space for the reception of some turns of the hose in the inactive position of the jetting hose (42), in which the working/nozzle head (42a) is retracted radially within the outer mantle surface of the tool housing (10a). 3. A tool as claimed in claim 1 or 2, characterized in that the jetting hose feeding body (96) has an upstream, partly helical hoseguiding groove (102) which merges with an essentially axial guiding groove, in which there may be arranged a telescope pipe (104), and whose downstream end merges into a curved guiding element or bed (82) for the gliding displacing motions of the jetting hose (42). 4. A tool as claimed in any of claims 1-3, characterized in that below a jetting hose portion within the tool housing (10a) adjacent to the working/nozzle head (42a) of the hose, in the active position, is arranged a movable/pivotable interacting arm (84) which is arranged to influence and cooperate, when the feeding speed exceeds the real hose penetration speed into the sediment (80), with a change-over means in the form of a switch (108), which again influences the driving motor (90) for the drum/feeding body of the jetting hose to reverse with the aim of re-establishing the feeding conditions.