Method for opening water-bearing horizons by a vertical well and device for realization of said method
FIELD: oil and gas extractive industry.
SUBSTANCE: method includes use of device providing for manufacturability of assemblage of casing and drilling columns and concurrent drilling by two columns, provided with independent drives, and drilling, by casing column, of non-stable rock solids performed with frequency no greater than one calculated from formula
where Vmec - mechanical drilling speed, m/min, Fr - friction forces against rotation, Ften - friction forces against linear displacement, R - casing column radius, m, α - angle between vectors of directions of linear and rotating movements.
EFFECT: higher effectiveness, higher productiveness, higher reliability.
2 cl, 5 dwg, 1 ex
The invention relates to the field of technology and engineering of construction of vertical boreholes for water conservation of the natural permeability of the aquifer and can be used for drilling vertical wells in complex hydrogeological conditions.
At the opening of sandy aquifers important issues are the protection walls constructed borehole from collapse and conservation of the natural permeability of the rocks, which causes the emergence of new ways and new installations along with the already well-known and traditional.
So, there is a method of opening a sandy aquifer vertical wells using as a flushing agent mud. Mud on the one hand performs the function environment, retaining particles of solids from sedimentation, on the other hand, it creates additional pressure on the reservoir, which manages to keep the walls of the well from caving.
The disadvantage of this method is the ingress of mud filtrate into the formation and the formation of mud cake on the borehole walls. The clogging layer clay solution reduces its permeability in prefiltrov area that calls for a clay formation removal and reservoir. This process takes several days, but does not completely restore the shape of the well production rate (Evoxac and other "The drainage of the fields in the construction of iron ore mines", Moscow, "Nedra", 1977, p.61, table 19).
To eliminate this disadvantage it is known the use of the method of opening a sandy aquifer using as a wash liquid pure water at direct and reverse circulation [Vamparism, Vselected. Filters drilling wells. M., Nedra, 1976, s-287].
When drilling with direct flushing water drilling pump on the drill string serves to rock cutting tool. The water supplied to the slaughter, shall decide annular space the cuttings to the surface.
When drilling with reverse washing water is fed into the annular space between the borehole wall and the drill column, where it together with the slurry rises in the drill string to the surface. Performance drilling in this way is higher than when drilling with a clay solution, by reducing several times on the field, well, its flow rate is also greater than the flow rate of wells drilled with clay mortar, making this approach has gained worldwide recognition.
The disadvantages of this method should include a mandatory condition of its implementation - the excess pressure of the column of drilling fluid in the well above the hydrostatic pressure of the water in the reservoir at 3-5 m Vogt as West the monitoring level in the well is difficult, in practice, this level of support at the wellhead, which leads to a large consumption of water in connection with the merger of its sandy layer (in some cases up to 60-80 m3/hour).
The disadvantages are considered analogues should be considered a violation of the natural permeability of the reservoir during the construction of the well.
This deficiency is partially removed in a known manner of opening the sandy aquifers under the protection casing with simultaneous removal of the rock face with the help of special jelonek deployed on the rope. Moreover, the casing is carried out either under its own weight, or with a parallel application to the casing shock loads, i.e. the casing give the function working. In this way, the opening of the aquifer is crucial that the penetration depth of the casing into the formation. This parameter is determined by many factors: the depth of the aquifer, its power, pressure, technology bailing rock bottom (frequency pulling-lifts jelonki, its design), and many others. Typically, the depth in the sandy layer of a few meters. The reason is that to ensure the stability of the borehole walls in this way is impossible because of the constant fluctuation of the static pressure of the reservoir, which is created by the shell when the drawing of the breed along with the water.
When a powerful layer to provide the reservoir for all its power it is necessary to use several sizes of columns. It is very time consuming, bulky, and, therefore, expensive and inefficient method, which is used very rarely and mainly for drilling shallow wells. Important advantages of the method are the preservation of the natural permeability of the reservoir and the possibility of opening the aquifer combined column, part of which is a filter section, which is installed at a certain interval.
For reducing completion time, reduce the labor intensity of planting filters and increase water yield of wells using the method of planting filters Shoe-extender. [A.S. 623948, B 34, 1978].
The improved method of opening the sandy aquifers carried out with a simultaneous change or improve facilities for drilling.
Thus, the known device for drilling "Phoebus, Ahbau intended for drilling shafts rotary method with backwashing. Penetration rate is 0.3-0.8 m/h, the minimum commercial drilling speed of 30 m/month. The equipment is made of blocks, easily assembled and easily transported. In the installation kit includes a derrick, drilling system, winch, rotor, buril the th column with screw locks, set the Boers, equipped with cutters or cones, mobile compressors and equipment for cooking and cleaning solutions [Agisilaou and other "Rigs to drill wells and shafts". Handbook, M.: Nedra, 1985 s-267]. The disadvantages of the installation should include the complexity, the greater the intensity, the inability to avoid the disadvantages inherent in the method of drilling a single column of drill pipe.
From a technical level it is also known construction of vertical wells the two working pipes (casing and drill). So, at the request of France No. 2071226 and patent RU No. 2018621 (P. 2018621, publ. 30.08.94) the device includes the basic machine with rail, casing pipe with rock body and drives its rotation and feed, and the feed mechanism is made of screw, i.e. the development wells is possible only when forced submission of the working bodies of the coil pairs. However, the development of soft soils this leads to over-filling of the cavity of the pipe soil, which in turn causes an overload of actuators working bodies. Therefore when developing a soil solid categories, such as meters, drilling carried out cyclically first screw holes, then scoop. When drilling in soft soil resistance development is significantly reduced. So prohod the wells produce no additional pressure efforts on working bodies. The use of this device enables the following operations to manage the working bodies: force flow into the well separately or together each of the working body or flow under its own weight, alternately supply first screw auger, then the bucket mounted on the casing tube, but without stopping the transport of the developed soil from inside the pipeline.
Considered the device is intended for drilling of wells, the length of which does not exceed the length of the operating rod capable of independent drilling two columns of tubes only in hard soils and absolutely not adapted for the construction of vertical wells in sandy aquifers.
Thus, in a certain technical level could not locate the closest analogue as for a method of opening aquifers, the device for its implementation.
The objective of the invention is to expand the number of ways of opening unsustainable aquifer vertical deep or shallow well with the preservation of natural patterns and natural permeability of the walls of the borehole with the establishment of the filter during drilling and the creation of the installation for its implementation.
Technical results that may be obtained when implementing the claimed izopet the tion, are:
for the method
- ensuring the conservation of natural structure and permeability of the aquifer;
- retaining walls constructed borehole from caving;
- reduction in the probability of curvature of the borehole;
- improved performance;
- reduction of energy intensity;
- the combination of the operations of drilling and installation of filters;
the capacity of the column;
- reliability and enabling opening of the aquifer without disturbing the natural structure and natural permeability;
- expansion of the number of facilities for dissection unstable aquifers.
The solution of the stated problem and achieve the above results became possible due to the fact that in the method of opening unsustainable aquifer vertical borehole, comprising the drilling of this well in sandy water-saturated rocks two independent columns casing and drill through the controlled transmission of the tools that equip the ends of both columns, loads, providing the deepening of the well, removing from the bottom of the destroyed rocks and installation in the borehole with at least one filter element in the zone of not less than one aquifer drilling casing unstable rock ASU is estlat rotation frequency, providing minimum friction of its rotational-translational motion and not exceeding calculated by the formula
α - the angle between the vectors of the translational and rotational motions;
FBP- friction rotational movement:
FOSthe friction force forward movement;
R is the radius of the casing,
at least one filter element is installed in the borehole during the drilling process by its inclusion in the composition of the casing with the possibility of shipping to construct the well to a predetermined threshold, removing the destroyed rocks with slaughter carried out through the annular space through the water at the bottom through the inner column in a quantity sufficient for the removal of destroyed rock at the wellhead, and the capacity of drilling and casing produced by the preliminary discharge of the rotator of the drill string from the axis of the drilling in the plane perpendicular to it.
In preferred examples, the execution method, casing and drill string rotate out of phase, the borehole wall is cut by the tool in the form of a cutting ring with a cutting angle of 45-60°, facing conical surface in the annular space with the external d is amerom, 1.1-1.15 times greater than the external diameter of the casing string.
To set the opening unsustainable aquifer vertical borehole problem solving and the achievement of the above results became possible due to the fact that the installation includes a mud pump to supply water at the bottom, a platform with a vertical frame, which strengthened the guides to move vertically installed movable frame, the movable frame at right angles to it is fixed parallel to each other two fixed frame with guides providing moving them, respectively, rotators drilling and casing perpendicular to the axis of the drilling, with each of the rotators is associated with a corresponding adjustable wire rotator casing provided with a node for mechanical screwing and unscrewing of the sections of casing and drill pipe, and a casing included at least one filter element can be installed in the borehole at a given elevation in the drilling process.
In a preferred example of execution of the installation as a tool in the casing pipe is fixed cutting tool in the form of a ring with a cutting angle of 45-60°, facing conical surface in the annular space and a diameter of 1.1-1.5 times the diameter of bidney columns.
Adjustable rotation of the casing respectively, the claimed limit formula provides optimum drilling by taking into account such variables as ROS- axial component acting on the column, depending on the weight of the column, Rside- mountain pressure acting on the casing from the borehole walls. When the message column axial movement and rotation occur frictional forces impeding its movement. These forces are in the opposite direction of axial and rotational movement, and opposite to the velocity vectors. The ratio of the frictional forces translational and rotational motion depends on the angle αformed between the vectors of the translational movement of the column down and rotating around the axis of the borehole, or respectively the forces of frictionwhere Foc- the friction force forward movement of the column down, caused by rock pressure;
where f is the friction coefficient of steel on rock,
where FBP.- friction rotational movement of the casing;
where Vfurmechanical drilling speed, m/min;
R is the radius of the casing, m;
Pt- frequency of rotation of the casing, rpm and is based on α and Vfurcalculate the optimal speed, providing minimum friction rotational-translational motion (see formula 1).
In General, if you steady the walls of the borehole side friction force of the column is small and is determined by the force of the pressing columns to the walls of the well and the coefficients of friction. When unstable walls of the magnitude of lateral pressure is determined by the lateral pressure Psidewith the side walls of the wells. In this case, it is defined by the horizontal component of ground pressure and friction breed of steel.
The flow of washing liquid (water) are selected from conditions sufficient for the removal of destroyed rock. There is no need, in contrast to analogues, to keep the excessive pressure on the seam to hold the walls of the borehole from caving, so the removal of the destroyed rock bottom with clean water and allow it to be sufficient for this purpose, allows to increase the system's efficiency in comparison with analogues, uses this principle.
Interval of the filter element or elements, their design, duty cycle and other parameters are also specified and regulated geological-technical outfit. When calculating the filter column is calculated on the torsional strength. The inclusion during drilling stood in the casing of the filter element allows you to combine the operation of drilling and planting filter, reducing the time of the construction of the well and increases the adaptability of the method.
The rotation of the casing and drill string out of phase reduces the probability of curvature of the borehole, and therefore, to reduce friction.
Cutting of walls constructed of the well tool in the form of a cutting ring with a cutting angle of 45-60°, facing conical surface in the annular space with the outer diameter of 1.1-1.15 times greater than the external diameter of the casing, increases the possibility of preservation of the natural rock properties (permeability and structure) and the direction of the rocks in the annular space where it is carried by water to the surface.
The invention is illustrated by the following drawings:
figure 1 - view of the device side;
figure 2 - installation front;
figure 3 - layout of casing and drill string in the borehole;
4 is a nomogram for determining the friction force due to the axial displacement forces of the casing depending on the mechanical drilling speed (Vfur) and friction coefficient breed of pipe (f);
5 is a nomogram for determining the torque on the casing depending on the Vfurand f.
Installation (figure 1 and figure 2) for implementing the inventive method for opening unsustainable aquifer vertical well is the th horizontal platform 1, mounted on the chassis 2 and is rigidly connected with the vertical frame 3, having the guides 4 to move vertically movable frame 5, on which is fixed to the rotator 6 with the casing 7 and the rotator 8 of the drill string 9. On the movable frame 5 is perpendicular she installed the frame 10 with the guides 11, which is perpendicular to the axis of the drilling moves the rotator 8 of the drill string 9 by means of the hydraulic cylinder moving 12 installed between the rails 11 and rigidly connected to the housing of the rotator 8. To ensure alignment of the spindle 13 of the rotator 6 and the spindle 14 of the rotator 8 they are provided with a device for rigid fixation (not shown), excluding care of the drill string 9 from the axis of rotation. For removal of the rotator 6 from the axis of the borehole on a movable platform 5 mounted frame 15 with the guides 16, parallel guides 11 and the hydraulic cylinder 17 to move the rotator 6. Transfer rotation and axial forces the casing 7 through the nodes for mechanical screwing and unscrewing of the sections of casing and drill pipe in the form of hydraulic capture (cartridge) 18 mounted on the case of the rotator 6 of the casing 7, a gripping mechanism which rotates together with the spindle 13 of the rotator 6. To hold the sections of the casing 7 on the stationary platform 3 is the hydraulic capture (HYDR is licenci key) 19, who in the seizure of the casing 7 can hold it from turning.
Moving the fixed frame 5 on the vertical frame 3 is carried out using a hydraulic cylinder 20 (cylinder stroke filing should be 10-15% greater than the length of sections of drill and casing pipes). As the drilling is carried out in two columns 7 and 9 at the same time, and capacity must be done sequentially (first drill, then casing). The length of both columns must be the same. In the lower part of both columns 7 and 9 are equipped with tools (see figure 3). On the drill string 9 is set as such a tool or a roller or blade of the chisel 21. The casing 7 is equipped with a tool in the form of the cutting ring 22 with a cutting angle of 40-60°, the conical surface of which is turned inward, and the outer surface has a cylindrical shape. Conical surface reinforced solid alloy. The outer diameter of the tool 22 is larger than the diameter of the casing 7 by 10-15%. Due to this factor, the form he cuts the rock from the borehole walls and directs it into the well, which ensures the preservation of the natural rock properties (permeability and structure). When drilling supply drilling fluid to the drill string 9 is drilling pump (not shown) via pressure hose 23 through the seal-swivel 24,where the column 9 she served on the working face through the bit 21 and extends upward through the annular space 25.
At the bottom of the vertical frame 3 has an additional hydraulic torque wrench 26 for emergency hold the casing 7. Above the spindle 13 of the rotator 6 of the casing is installed hydraulic gripper 27 to hold the drill string 9. The hydraulic rotator 6 and 8, the hydraulic supply are driven from the pumping station 28, the hydraulic pumps (not shown) which are connected with diesel-elektrostancij 29 or an electric motor, and the drive control is done through their connection with the remote control 30.
With the remote control 30 controls the lifting frame 3 from horizontal to vertical. This operation is performed by the hydraulic cylinders 31 and 32. The rotation is performed around the hinges 36.
The operation of lifting and lowering of the casing sections 7 and drill 9 tubes provided with lifting mechanism 33 winch 34. The leveling of the platform 1 and the perception of axial loads at round-trip operations and drilling is carried out with the help of hydraulic jacks 35, controlled from the remote control 30. Translation in the transport position of the frame 3 from the vertical to the horizontal position with the help of hydraulic cylinders 31 and 32 by rotation around the hinge 36.
The requested installation operates as follows. The installation is mounted on the platform, gidrol is indrow 31 and 32 vertical lift frame 3 in a vertical position and fixed. The thus prepared the installation using hydraulic jacks 35 negate. After that, proceed to the preparation for the drilling, which gather the layout of the casing 7 and the drill 9 (figure 3). This is done as follows. On the head section of the casing 7 install the tool 22. Lifting mechanism 33 by means of the winch 34 first gather a working layout of the casing 7. For this first working section is passed through the spindle 13 of the rotator 6 and clamped hydrosolate (hydraulic key) 19, and then raise the next section of pipe 7, again passed through the spindle 13 of the rotator 6. Clamp it in the Chuck 18, include the rotation of the spindle 13 and connect the sections in the column. These operations continue until such time as the tool 21 will not come in contact with the ground. After that, similarly collect the internal layout of the column 9. First on her head section set the bit 21, by means of the winch 34 and lifting mechanism 33 her up, pulled down into the casing 7, put on the plug (not shown) of hydraulic capture 27, fix, lifting mechanism is released, raise the next section of pipe 9 and produce the capacity of the column, using hydraulic capture 27 or 18. Building and running columns 9 carried out cyclically, up until Dolo is about 21 hits the surface of the earth.
Technological operations, building columns is achieved by removal of the bit of the drill string from the well axis in the direction, this provides the possibility of maneuvering lifting mechanism 33.
Following these operations, the casing 7 is clamped in the hydraulic capture (Chuck) 18, release the hydraulic capture of key 19, sum up the rotator 8 to the center, the spindle 14 is connected with the drillstring 9 and tune to the specified frequency of rotation of the drill 9, then the casing 7 of the column, include the submission of the moving frame 5 down, with the help of the hydraulic cylinder 20 to regulate the axial pressure on the face, include mud pump (not shown) and start drilling. The rotational speed of the drill string 9 choose from the effective destruction of the rock bit 21 (usually in the range of 80-200 rpm). The rotational speed of the casing 7 at the initial moment, when the borehole wall is stable, the maximum possible. Upon reaching the drilling tool of unstable rock casing start to rotate with a rotational speed, which is calculated by the formula
R is the radius of the casing,
FBP- friction rotational movement:
f - coefficient of friction of steel on rock;
Pside- mountain pressure acting on the side walls of the well bore on the casing (Psidecalculated by known methods);
FOS- the friction force of the forward movement of the casing downward pressure caused by the mountain.
When drilling in difficult conditions, it is necessary for each well to make a geological and technical outfit (the regulations), which pointervalue paint predicted (calculated) parameters: axial force at the bottom, rock pressure, friction translational and rotational movement, drilling speed, the rotation frequency of the external columns. For decrease (reduction) of curvature of the wells, and therefore, to reduce friction casing in the preferred implementation report left-hand rotation.
Industrial applicability of the claimed method and installation for its implementation the following example illustrates a specific implementation.
Hydrogeological conditions of work:
- the upper part of the incision to a depth of 1.5 meters presents a vegetative layer;
from 1.5 m to 2.5 m - loam;
from 25 m to 35 m fine-grained flooded Sands pressure;
- static water level is at a depth of 15 m;
- at the base of the aquifer is overlain by dense videoporn the e clay with a capacity of more than 15 meters
The purpose of the well is potable and household water group, individual homes with an estimated water consumption of 4-5 m3/hour.
Well constructed for the installation of pump ECV-5 or ECV-6 with a diameter of filter element 168 mm Borehole constructed by drilling two independent columns: a casing with an outer diameter of 168 mm and a drill with an outer diameter of 89 mm, removing rocks from the bottom by applying clean water through the drill string.
The casing is equipped tool in the form of a ring with a cutting angle of 45-60°, facing conical surface in the annular space with the outer diameter of 185 mm, which is 1.1 external diameter of the casing. Above the cutting tool there are 7 sections deaf pipes, on which the filter of the 7 sections (perforated pipe slotted perforation with crack size of 0.5-0.7 mm and a duty cycle of about 14%). Into the well on a given mark the filter element or elements delivered during drilling, namely in the area of fine-grained watered sand pressure. The other sections of the casing are also collected from deaf pipes.
The thread on the pipe left the tape with dvuhaktnoy thread and pitch of 12 mm, which provides a high speed extension of the casing sections (2-3 min per connection). Casing made of high-strength steel grade D.
Internal BU the strong column are collected from pipes with an external diameter of 89 m and equip a tool in the form of a blade of the cutting bit of the type with a diameter of 145 mm
The rotational speed of the casing are calculated according to the formula
R is the radius of the casing;
where FBPFOSaccordingly, the friction force of rotational and translational movement of the casing. These forces are calculated in advance in the preparation of geological and technical outfit on the well. For practical use, in accordance with the proposed drilling method constructed nomograms for determination of the friction of the forward movement and cool moments at 1 PM column. They are presented in figure 4 and 5.
From much experience opening the sandy aquifers practically the speed of the column is within 2-5 Rev/min Below 2 rpm to keep the frequency is difficult because of the complexity of regulating the flow of oil in the hydraulic control actuator rotation. First include the rotation of the inner column, then the casing, and the rotation of the latter is carried out in the opposite direction, include the water supply using a mud pump and drill to the depth of the section. Then disconnect the spindle rotator drill string from the column, assign the rotator in a horizontal plane from the axis of the well, increasing first drill, then the casing string.
After Nar is farming the next section rotator drill string is moved towards the axis of the drilling connecting the spindle with the column. And repeat the drilling process.
Time to drill 1 p.m. wells is increased by 20-30% due to the additional cost of increasing the casing, but is reduced due to the overlapping operations of landing a casing string with drilling of this column, and operations delivery and installation in the area of the filter with the operation of drilling, casing, part of which included the specified filter element (or section filter elements).
The following results were achieved drilling:
Vfur- 0.4-0.7 m/min;
Vthose- 5-7 m/h;
Vcommercial- 1.5-2 m/h.
As you can see from the example, the method of opening aquifers vertical borehole and installation for its implementation in the claimed combination of features have practical applicability, ensure the preservation of the natural patterns and natural permeability of the walls of wells, installation of more compact, reliable and productive in comparison with the known analogues, allows to combine the operations of drilling, fixing the walls and installation in the borehole filters in given areas at the time of creating this well.
1. The method of opening unsustainable aquifer vertical borehole, comprising the drilling of this well in sandy water-saturated rocks two independent columns casing and drill potenrequirement transfer instruments which will equip the ends of both columns, loads, providing the deepening of the well, removing from the bottom of the destroyed rocks and installation in the borehole with at least one filter element in the zone of not less than one aquifer, while drilling casing unstable rock is performed by the rotation frequency, providing minimum friction of its rotational-translational motion and not exceeding calculated by the formula
Vfurmechanical drilling speed, m/min;
FBP- friction rotational movement;
FOSthe friction force forward movement;
R is the radius of the casing m,
α - the angle between the vectors of the translational and rotational motions,
at least one filter element is installed in the borehole during the drilling process by its inclusion in the composition of the casing with the possibility of shipping to construct the well to a predetermined threshold, removing the destroyed rocks with slaughter carried out through the annular space through the water at the bottom through the inner column in a quantity sufficient for the removal of destroyed rock at the wellhead, and the capacity of drilling and casing production is t by pre-assignment of the rotator of the drill string from the axis of the drilling plane, perpendicular to it.
2. The method according to claim 1, characterized in that the casing and the drill string rotate out of phase.
3. The method according to claim 1, characterized in that the wall of the bore cut by the tool in the form of a cutting ring with a cutting angle of 45-60°, facing conical surface in the annular space with the outer diameter of 1.1-1.15 times greater than the external diameter of the casing string.
4. Installation for the opening of aquifers vertical well, including mud pump for supplying water to the bottom, a platform with a vertical frame, which strengthened the guides to move vertically installed on her mobile frame, a movable frame at right angles to it is fixed parallel to each other two fixed frame with guides providing moving them, respectively, rotators drilling and casing perpendicular to the axis of the drilling, with each of the rotators is associated with a corresponding adjustable actuator, the rotator casing provided with a node for mechanical screwing and unscrewing of the sections of casing and drill pipe, and the casing columns included at least one filter element can be installed in the borehole at a given elevation in the drilling process.
5. Installation according to claim 4, characterized in that as the tool about adney column fixed cutting tool in the form of a ring with a cutting angle of 45-60°, facing conical surface in the annular space and a diameter of 1.1-1.15 times the diameter of the casing columns.
FIELD: oil and gas production.
SUBSTANCE: invention relates to insulating formation water inflow in gas and gas condensate wells with the aid of coltubing techniques. In particular, flexible conduit is descended through the tube space of well operated under pressure to the bottom with the aid of coltubing installation. Latches on tube and annulus spaces are opened. Well hole is filled through flexible conduit with gas condensate. Grouting mortar is prepared in preparation block by mixing cement mortar with setting retardant and mortar flowability enhancer in a calculated amount needed to prevent formation water inflow. Further, flushing fluid, e.g. methanol, is pumped through flexible conduit in amount constituting 0.3-0.6 volume of flexible conduit. Annulus space is closed and grouting mortar is pumped through flexible conduit in amount required to fill well hole in interval of water-inflow part of formation. When grouting mortar in hole rises to specified height, tube space is closed and grouting mortar contained in flexible conduit is forced into water-inflow part of formation by in series pumped flushing fluid and displacing solution: for example first methanol in amount 1.0-1.3 volumes of flexible conduit and then gas condensate in required amount, which however does not exceed internal volume of flexible conduit, until grouting mortar begins being pumped in amount of 0.3-0.5 volumes of flexible conduit. Then tube and annulus spaces of well are opened and gas condensate begins being simultaneously pumped into tube and annulus spaces in order to prevent rise of grouting mortar therein above interval of the water-inflow part of formation. Thereafter, bottom of flexible conduit is raised by 1 m above indicated interval and excess of grouting mortar is cut and washed away with gas condensate passed through flexible conduit into tube space, where excess grouting mortar remains in fluid state. After cement setting expectation time, flexible conduit is descended to the top of cement column and tests the latter for strength applying 4.0-5.0 kN loading by means of injector of coltubing installation through flexible conduit. Finally, cement bridging is subjected to hydraulic pressurization and flexible conduit is removed from well.
EFFECT: enabled formation water inflow insulation without killing of well and restricted pollution of water-inflow part of formation.
3 cl, 1 dwg
FIELD: oil and gas extractive industry.
SUBSTANCE: device has pipe-like body with detachable upper and lower sleeves. Concentrically to body, with possible rotation relatively to it, a cover is mounted with blades with scrapers placed spirally on its surface. To lower sleeve a reactive end piece is connected with slit apertures. End piece hollow is filled with granulated material engaging in exothermal reaction with acid. Lower portion of end piece is provided with check valve. Upper sleeve is provided with check valve having locking element in form of sphere with shelf and centering elements, to be dropped from well mouth. Base of saddle of check valve is made in form of disc having diameter equal to diameter of body. Pass aperture of saddle in lower portion is overlapped with easily destructible and easily removed element. Length of sphere shelf is greater than height of pass aperture of saddle of check valve of upper sleeve.
EFFECT: higher reliability, higher efficiency, broader functional capabilities of device.
3 cl, 4 dwg, 1 tbl