RU2651714C2 - Two-packer arrangement of the oil-producing unit with insulation of casing leakage failures - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to a two-packer arrangement of an oil production unit with insulation of casing pipe leakages. Two-packer arrangement of the oil production unit with insulation of casing string leakage seals comprises successively lowered on the elevator tubing string and an electric submersible pump installed in the well with a power cable from the control station, two packers with cable entry, isolating pipe leakages in a certain interval of the casing, two columns of pipes of larger and smaller diameters forming an annular cavity for releasing the gas cap from the annulus below the lower packer into the annulus above the upper packer through the radial channels of the crossflow sleeves disposed below and above the packers, respectively, hermetically sealed by central channels with a string of pipes of smaller diameter for lifting oil to the surface, hermetically sealed by a stuffing box coupling connected to an electric drive pump. Lower packer is made with a supporting anchor device. Column of pipes of smaller diameter with the upper end is movably connected to the central channel of the upper clutch of the cross flow, provided with an epiploon, with possibility of axial displacement of the end of the column beyond the end of the cross-flow coupler to a length at least equal to the compensation value of the positioner error of the packers isolating pipe leakages in a certain interval of the casing string. On the side of the nipple of the stuffing box sleeve, a smaller diameter pipe string is provided with a centralizer for assembling the pipes in a column for lifting oil to the surface.

EFFECT: technical result is increase in reliability.

1 cl, 1 dwg

Description

The invention relates to the field of mining, in particular to oil production, and can be used in oil wells in violation of the tightness of the casing pipes.

Known packer containing a barrel and packer nodes with sealing elements, a hydraulic cylinder, a piston and a system of interconnected holes. The packer is equipped with a bypass valve with a housing made in the form of an inverted glass, and in it there is a guide sleeve with channels in the walls and a locking element. Several through holes and several holes with an exit to the side wall are made in the bottom of the casing, and the packer units are installed in the well with the opposite direction of movement of the hydraulic cylinders with an interval to eliminate leaks in the production string. Patent RU 2175710 C2. Packer (options). - IPC: ЕВВ 33/12. - 10.11.2001). The disadvantage of the technical solution is the lack of the possibility of bleeding associated petroleum gas, which reduces the flow rate of the well.

Known two-packer installation for operating wells with an electric drive pump with simultaneous isolation of the leakage interval, including two columns of pipes of larger and smaller diameters installed concentrically in one well, two packers with cable entry, insulating casing pipe leaks, two cross-flow couplings located respectively lower and higher packers and hermetically connected to the pipe string of smaller diameter, disconnector, bypass circulation valve, sb obvious valves of mechanical principle of operation, circulation valve with shear pins of hydraulic principle of operation and equalizing valve. The cavity between the pipe columns of larger and smaller diameters is connected to the well cavities below and above the cross-flow couplings for producing reservoir fluid through eccentric through longitudinal channels made of an expanded C-shaped. The cavity of the pipe string of smaller diameter is hydraulically connected to the spaces above and below the packers through transverse radial for gas bypass. Knockdown valves are located respectively under the lower and upper packers. In the case of cross-flow couplings in a direction parallel to the axis of the couplings, a longitudinal groove for cable laying is made, the installation is equipped with a control cable, for example fiber optic. The unit is equipped in the upper part above the disconnector with a hydraulic anchor. (Patent RU 2534876 C1. A two-packer installation for operating wells with an electric drive pump with simultaneous isolation of the leakage interval and a circulation valve. - IPC: Е21В 34/10, F04D 13/10, Е21В 33/124. - 10.12.2014). The main disadvantage of the known technical solution is the design complexity of the two-packer installation, which reduces the reliability of well operation.

The known arrangement of 2PIM-KV-GK with isolation of casing pipe leakages in an oil well, containing an electric drive pump, two packers with cable entry, insulating casing pipe leakages in a certain interval of the well, two columns of pipes of larger and smaller diameters forming an annulus for passing associated petroleum gas from the annulus below the lower packer into the annulus above the upper packer through the radial channels of the cross-flow couplings, lower and higher packers, respectively, connected by central channels to a string of pipes of smaller diameter for oil production, hermetically joined together by movable stuffing box couplings to compensate for the positioning error of packers with a certain interval, isolating casing leakages connected to the electric drive pump. (Product catalog 2016 of the Scientific and Production Company "GEONIK", p. 37). This technical solution is taken as a prototype.

The main disadvantage of the known technical solution adopted for the prototype is the movable stuffing box couplings integrated into the pipe string of smaller diameter, compensating for the positioning error of the packers with a certain interval of casing leakage, making installation difficult and reducing the reliability of the operation of an oil producing well.

The main task to be solved by the claimed invention is aimed at reducing the complexity of mounting the equipment layout in oil wells with casing leakages by eliminating the number of tripping operations and increasing the reliability of operation by simplifying the design of the pump unit.

The technical result is to increase the reliability of the operation of oil wells while isolating violations of the tightness of the casing pipes.

The specified technical result is achieved by the fact that, in the well-known two-packer arrangement of an oil production unit with isolation of casing pipe leakages, containing successively lowered pipe pipes and installed in the well an electric drive submersible pump with a power cable from the control station, two packers with cable entry, insulating violation of the tightness of the pipes in a certain interval of the casing string, two columns of pipes of larger and smaller diameters forming an annulus a chamber for bleeding the gas cap from the annular space below the lower packer into the annular space above the upper packer through the radial channels of cross-flow couplings located below and above the packers, respectively, tightly connected by central channels to a pipe string of smaller diameter to lift oil to the surface, hermetically joined by the stuffing box according to the proposed technical solution, the lower packer is made with a supporting anchor device, according to the proposed technical solution, a pipe coupling connected to an electric drive pump, the pipe string of smaller diameter with its upper end is movably coupled to the central channel of the upper cross-flow coupling equipped with an oil seal, with the possibility of axial displacement of the column end beyond the end of the cross-flow coupling by a length at least equal to the compensation value for positioning errors of packers that insulate pipe leakages in a certain the interval of the casing, and on the side of the nipple of the stuffing box coupling, the string of pipes of smaller diameter is equipped with a centralizer for assembling pipes in the columns to lift oil to the surface.

The analysis of the prior art by the applicant has made it possible to establish that there are no analogues that are characterized by sets of features identical to all the features of the claimed two-packer arrangement of an oil production unit with isolation of casing pipe leakages. Therefore, the claimed technical solution meets the condition of patentability "novelty."

The search results for known solutions in the art in order to identify features that match the distinctive features of the prototypes of the claimed technical solution have shown that they do not follow explicitly from the prior art. From the prior art determined by the applicant, the influence of the transformations provided for by the essential features of the claimed technical solution on the achievement of the specified technical result is not revealed. Therefore, the claimed technical solution meets the condition of patentability "inventive step".

The claimed technical solution can be used in oil wells according to generally accepted technology. Therefore, the claimed technical solution meets the condition of patentability "industrial applicability".

The presented figure schematically shows a two-packer arrangement of an oil production unit with isolation of casing pipe leakages.

, по меньшей мере, равную погрешности позиционирования пакеров 4 и 5, изолирующих нарушения герметичности 6 труб в определенном интервале L обсадной колонны 7. Колонна труб меньшего диаметра 9 со стороны ниппеля сальниковой трубной муфты 17 снабжена центратором 20 труб при сборке их в колонну 9 для подъема скважинной нефти на поверхность.The two-packer arrangement of the oil production unit with isolation of casing pipe leakages contains successively launched electric pipes 1 on the string and installed in the well at the design depth of the electric drive pump 2 with a power cable 3 from the control station (SU), two packers 4 and 5 with cable entry, located at a certain interval L, insulating leakages 6 of the casing pipe 7, two columns of pipes 8 and 9 of larger and smaller diameters, respectively, forming each other an annular cavity 10 for bleeding the gas cap from the annular space 11 under the lower packer 4 into the annular space 12 above the upper packer 5 through the radial channels 13 and 14 of the cross-flow couplings 15 and 16, respectively, located below and above the packers 4 and 5, hermetically connected by central channels with a pipe string of smaller diameter 9 for lifting oil from the well, hermetically sealed with a stuffing box coupling 17 connected to an electric drive pump 2. The lower packer 4 is made with a supporting anchor device 18. The column t 9 UB smaller diameter upper end movably interfaced with a central channel upper cross-flow sleeve 14 provided with an oil seal lip 19, with the possibility of axial displacement of the end of the column 9 after coupling face 16 on the cross flow length

at least equal to the positioning error of the packers 4 and 5, isolating the leakage of 6 pipes in a certain interval L of the casing 7. The pipe string of a smaller diameter 9 from the side of the nipple of the stuffing box coupling 17 is equipped with a centralizer 20 of the pipe when assembling them into the column 9 for lifting well oil to the surface.

The operation of the two-packer layout of the oil production installation with isolation of casing pipe leakages is as follows.

, по меньшей мере, равную погрешности позиционирования пакеров 4 и 5, изолирующих нарушения герметичности 6 труб в интервале L обсадной колонны 7. Аксиальным смещением конца колонны труб меньшего диаметра 9 вдоль центрального канала верхней муфты перекрестного течения 14, снабженного манжетным сальником 19, муфту 14 закрепляют на торце пакера 5 с кабельным вводом таким образом, чтобы конец колонны труб меньшего диаметра 9 выступал из муфты перекрестного течения 16 на длину

, по меньшей мере, равную погрешности позиционирования пакеров 4 и 5, изолирующих нарушения герметичности 6 труб в заданном интервале L обсадной колонны 7. К верхней муфте перекрестного течения 14 присоединяют колонну лифтовых труб 1, на которой нефтедобывающую насосную установку спускают в скважину до проектной глубины, затем нижний 4 и верхний 5 пакеры переводят в рабочее положение возвратно-поступательными движениями с последующим закреплением их в обсадной колонне якорным устройством 18, после чего запускают насосную установку в работу, подключая к электроприводному насосу 2 по силовому кабелю 3 электропитание от СУ. Нефть под давлением насоса 2 поднимается сначала по колонне труб большего диаметра 8, затем по колонне труб меньшего диаметра 9, установленной в центральных каналах муфт перекрестного течения 15 и 16, через сальниковую трубную муфту 17, и по колонне лифтовых труб 1 выкачивается на поверхность скважины. Стравливание газовой шапки от попутного нефтяного газа из-под нижнего пакера 4 производится через поперечные радиальные каналы 13 и 14 муфт перекрестного течения 15 и 16 по межтрубной полости 10 из затрубного пространства 11 под нижним пакером 4 в затрубное пространство 12 над верхним пакером 5 на поверхность скважины.For oil production from a well with a leak in the casing string 6, as the descent into the casing 7 takes place, the oil production unit is sequentially assembled on the well surface and lowered into the casing 7. First, the electric drive pump 2 with a power cable 3 is mounted on a pipe string of larger diameter 8, to which, through a predetermined number of pipes, a cross-flow coupling 15 and a lower packer 4 with a cable entry are connected. Then, as the pump unit with the lower packer 4 is lowered, a predetermined number of pipes of a larger diameter pipe 8 with a length equal to the design interval L is installed over the latter to isolate the pipes of the casing 7 with impaired tightness 6 and the upper packer 5 with cable entry. A pipe string of a smaller diameter 8 is lowered through an upper packer 5 into a pipe string of a larger diameter 8 with a stuffing box coupling nipple 17, equipped with a centralizer 20 until the stuffing box coupling 17 is fully docked to raise the borehole oil to the surface, so that when assembling their end, the pipe string smaller diameter 9 protruded over the end of the cross-coupling 16 on the length

at least equal to the positioning errors of the packers 4 and 5, isolating the leakage of the pipes 6 in the interval L of the casing 7. Axial displacement of the end of the pipe string of smaller diameter 9 along the central channel of the upper cross-flow coupling 14 provided with a lip seal 19, the coupling 14 is fixed at the end of the packer 5 with a cable entry so that the end of the pipe string of smaller diameter 9 protrudes from the cross-flow coupling 16 for a length

at least equal to the positioning error of the packers 4 and 5, isolating the leakage of pipe 6 in a predetermined interval L of the casing 7. To the upper coupling of the cross-flow 14 connect the string of elevator pipes 1, on which the oil pumping unit is lowered into the well to the design depth, then the lower 4 and upper 5 packers are translated into working position by reciprocating movements, followed by fixing them in the casing with the anchor device 18, after which the pump unit is started up, p By connecting to the electric drive pump 2 via the power cable 3, power supply from the SU. Oil under the pressure of pump 2 rises first through a string of pipes of larger diameter 8, then through a string of pipes of smaller diameter 9, installed in the central channels of the cross-flow couplings 15 and 16, through an stuffing box coupling 17, and is pumped to the surface of the well through a string of lift pipes 1. The gas cap is vented from associated petroleum gas from under the lower packer 4 through the transverse radial channels 13 and 14 of the cross-flow couplings 15 and 16 along the annular space 10 from the annular space 11 under the lower packer 4 into the annular space 12 above the upper packer 5 to the well surface .

Upon completion of oil production or, if necessary, changing the oil production installation, lift the pump installation by pulling the lift pipe string 1 with a force exceeding its weight, at which the upper packer 5 moves upward and the lower packer 4 remains stationary, then continuing to tension both packers 4 and 5 are transferred to transport position and lift the installation from the well.

The advantage of the proposed two-packer layout of the oil production unit is the ability to maintain the flow rate of the well while isolating violations of the tightness of the casing pipe of the well.

Claims (1)

A two-packer arrangement of an oil production unit with isolation of casing pipe leakages, containing elevator pipes sequentially launched on the casing string and installed in the well with an electric drive submersible pump with a power cable from the control station, two packers with cable entry, insulating pipe leakages in a certain casing interval, two columns of pipes of larger and smaller diameters, forming an annular cavity for bleeding the gas cap from the annulus one lower packer into the annulus above the upper packer through radial channels of cross-flow couplings located below and above the packers, respectively, tightly connected by central channels to a pipe string of smaller diameter to lift oil to the surface, hermetically joined by a stuffing box coupling connected to an electric drive pump, characterized in that the lower packer is made with a supporting anchor device, and the pipe string of a smaller diameter with the upper end is movably mated to the central channel the upper cross-flow coupling, equipped with an oil seal, with the possibility of axial displacement of the end of the column beyond the end of the cross-flow coupling by a length at least equal to the compensation value for the positioning error of packers that isolate pipe leakages in a certain interval of the casing, and from the side of the stuffing box coupling the pipe string of smaller diameter is equipped with a centralizer for assembling the pipe into a pipe for lifting oil to the surface.

Images