RU2792459C1 - Emitter for creating a wave agitation on highly heavily oil fields - Google Patents

Abstract

FIELD: oil production.

SUBSTANCE: emitter for creating a wave agitation on heavily watered reservoirs of an oil field in order to increase the oil recovery factor from these reservoirs. The emitter for creating a wave agitation on heavily watered reservoirs of an oil field contains a bullet. The bullet is made in the form of a cylindrical body with the possibility of mounting on the lower end section of the drill pipes freely suspended in the well casing. Longitudinal cylindrical blind holes are made in the lower and upper ends of the bullet, and a chamfer is made on the lower end of the bullet. The bullet is made with the possibility of reciprocating movement inside the casing pipe to provide an impact action on a flat disk located at the bottom of the casing pipe at the interface between the phases of the productive formation and the bedrock in such a way as to ensure the conversion of the kinetic energy of the drill pipes freely suspended in the casing pipe into waves passing by the phase separation of the productive formation and bedrock. The length and diameter of the cylindrical body of the bullet are 1200 mm and 200 mm, respectively, and the depth and diameter of the longitudinal cylindrical blind holes in the ends of the cylindrical body of the bullet are 350 mm and 25 mm, respectively.

EFFECT: provision of a complex wave motion on the layers of the oil field.

1 cl, 1 dwg

Description

The invention relates to oil production, and in particular to the emitter to create a wave perturbation in heavily watered reservoirs of an oil field in order to increase the oil recovery factor from these reservoirs [E21B 28/00, E21B 43/25].

The prior art is known DOWNHOLE DEVICE FOR SHOCK-WAVE IMPACT ON PRODUCTION FORMATIONS [EN 146794 U1, publ. October 20, 2014], including a pressure pulse generator placed in the wellbore on a pipe string or on a cable. A piston with a longitudinal length is installed above the pressure pulse generator, which ensures effective reflection of shock-wave pressure pulses and limitation of the wave load on the pipe string or cable. The effectiveness of the shock-wave impact on the formation is increased due to the localization of this impact in the selected interval of the productive formation. In addition, the localization of the impact zone protects the threaded connections of the casing pipes and the cement stone in the annulus in the rest of the wellbore from dynamic loads. To limit the exposure interval from below, a similar piston can be installed under the pressure pulse generator.

The disadvantage of analogue is the ability to have a rehabilitating effect on a single well and at a limited distance.

The closest in technical essence is the METHOD OF WAVE INFLUENCE ON PRODUCTION FORMATION AND DEVICE FOR ITS IMPLEMENTATION [RU 2171354 C1, publ. 07/27/2001], while the known method includes the installation of a block of directional wave action in the well and the creation of hydrodynamic impacts on the above block. The device for implementing the method includes a load for applying hydrodynamic impacts, a lifting mechanism associated with the load, and a directional wave action unit. The block is formed by at least two cylindrical elements with axial and radial channels. One of the cylindrical elements is embedded in the cement bridge. Other elements are placed above it with the possibility of matching their axial channels. The lower end of the element built into the cement bridge is made in the form of a truncated ball. The axial channel of this element is made deaf from below.

The main technical problem of the prototype is the impossibility of generating waves passing in a plane along the interface between the phases of the reservoir and the bedrock, which leads to a limited perturbation zone of several meters and the inability to provide a comprehensive rehabilitative effect not only on the well, but also on the field as a whole.

The objective of the invention is to eliminate the disadvantages of the prototype.

The technical result of the invention is to provide the possibility of creating a source of wave disturbance on the layers of an oil field.

The specified technical result is achieved due to the fact that the emitter for creating a wave disturbance on heavily watered reservoirs of an oil field, containing a striker having a cylindrical body, characterized in that the striker is designed to be mounted on the lower end section of drill pipes freely suspended in the well casing, longitudinal cylindrical blind holes are made in the lower and upper ends of the striker, and a chamfer is made on the lower end of the striker, while the striker is made with the possibility of reciprocating movement inside the casing pipe to provide a shock effect on the casing located at the bottom of the casing pipe at the interface between the phases of the productive formation and the root rocks a flat disk in such a way as to ensure the conversion of the kinetic energy of drill pipes freely suspended in the casing into waves passing through the phase separation of the productive formation and bedrock, while the length and diameter of the cylindrical body of the striker are 1200 mm and 20 0 mm, respectively, and the depth and diameter of the longitudinal cylindrical blind holes in the ends of the cylindrical body of the striker are 350 mm and 25 mm, respectively.

Brief description of the drawings.

The drawing shows a general view of the emitter to create a disturbance field by means of a wave disturbance on heavily watered reservoirs of an oil field in accordance with one of the possible embodiments of the claimed invention, which indicates: 1 - head of the emitter, 2 - threaded connection, 3 - drill pipes, 4 - casing pipe, 5 - transverse grooves, 6 - chamfer, 7 - well surface, 8 - transducer, 9 - reservoir, 10 - bedrock, 11 - rubber gaskets.

Implementation of the invention.

An emitter for creating a wave disturbance on heavily watered reservoirs of an oil field is designed to increase the oil recovery factor from these reservoirs and includes a striker 1 having a cylindrical body and connected by a threaded connection 2 to the end section of the drill pipes 3 freely suspended in the well casing 4. In an advantageous embodiment of the utility model, the ratio of the length of the cylindrical body of the striker 1 to its diameter is 6:1. Based on the diameter of the casing, taking into account the tolerance, the diameter of the cylindrical body of the striker 1 is chosen to be 200 mm, and its length, respectively, is 1.2 m.

Transverse grooves 5 can be made on the striker 1 in the center and along its edges. A chamfer 6 is made on the lower end of the striker 1. Longitudinal cylindrical blind holes are made in the lower and upper ends of the striker 1 (not shown in the drawing). Said cylindrical blind holes are made with a depth of 300 to 400 mm, preferably 350 mm and a diameter of 20 to 30 mm, preferably 25 mm. The striker 1 of the emitter is made in one piece, but it can also be composite along the transverse groove 5 in the center.

The emitter due to the execution in the striker 1 longitudinal blind holes is a dipole-type emitter operating on the principle of an antenna.

An eccentric electric drive (not shown) is placed on the surface 7 of the vertical well, by means of which the reciprocating movement of the drill pipes 3 together with the striker 1 inside the casing pipe 4 is initiated.

A converter 8 of kinetic energy into waves is lowered into the casing pipe 4 at the depth of the interface between the phases of the productive formation and the bedrock, in a non-limiting embodiment of the invention, which is a flat disk. At the same time, when the striker 1 reciprocates in its lower position, the striker 1 provides a shock effect on the transducer 8, due to which waves are generated along the plane of the interface between the phases of the productive formation 9 and bedrock 10. Due to the execution of the chamfer from the end of the lower segment of the striker 1 6 ensures the prevention of damage to the transducer 8 in the event of a mechanical impact on it of the striker 1 of the emitter.

To limit the vibrations of the drill pipes 3 and prevent the destruction of the casing pipe 4 of the well between the drill pipes 3 and the casing pipe 4, seals are mounted, made in the form of rubber gaskets 11.

An emitter for creating a wave disturbance on highly watered reservoirs of an oil field is used as follows.

Freely suspended drill pipes 3 are lowered into the casing pipe 4 with the striker 1 of the emitter located at the end section of the drill pipes 3 and fixed to it by means of a threaded connection 2.

By means of an eccentric electric drive placed on the surface of a vertical well 7, vibrations are generated, due to the reduced rotation of the electric motor with the help of a connecting rod in a consolidated suspended position, the drill pipes 3 together with the emitter are reciprocated along the eccentric, and the vibrations from the eccentric electric drive through the drill pipes 3 is transmitted to the striker 1. At the same time, during the reciprocating movement of the striker 1 in its lower position, the striker 1 provides a shock effect on the transducer 8, which is a flat disk lowered into the casing 4 at the depth of the interface between the productive formation and the bedrock. New, providing the achievement of a technical result, is that due to the design of the emitter, which is a dipole type emitter operating on the principle of an antenna, consisting of a striker 1, from the ends of which blind round holes with a depth of 350 mm and a diameter of 25 mm are made along the longitudinal axis , the generation of a wave disturbance along the plane of the interface between the phases of the productive formation 9 and the bedrock 10 with energy from 100 to 1000 kJ is provided, propagating over a distance of several kilometers.

For a higher total effect, the emitter is sequentially moved along the section.

On the basis of hydrodynamic modeling of the process of developing model deposits, it was determined that the effective use of sources of acoustic vibrations is possible only with the appropriate selection of the parameters of the emitters, namely: the frequency spectrum, the radiation pattern, the location of the source, its power, based on the geological and physical characteristics and conditions for the development of the site formation before impact, namely: for each type of reservoir there is an optimal frequency of impact (for example, for a reservoir that is not subject to deformation with permeabilities: 30 mD - 1300 Hz, 100 mD - 1100 Hz, 300 mD - 900 Hz).

An example of a specific implementation.

Pilot-industrial use of the emitter to create a wave disturbance on heavily watered reservoirs of an oil field at the Moncharovskoye field of NGDU "Chekmagush-neft" ANK "Bashneft" showed high efficiency. The impact was carried out by a mobile pulsed source on the layout of pipes lowered into the well.

With this impact, based on the results of pilot operation, the optimal dimensions of the emitter were selected, namely, the length and diameter of the cylindrical body of the striker 1200 mm and 200 mm, respectively, as well as the depth and diameter of the longitudinal cylindrical blind holes in the ends of the cylindrical body of the striker 350 mm and 25 mm respectively. It was determined empirically that the impact on the formations of the field with an emitter with the specified characteristics has the maximum effect in the form of a decrease in the water cut of the produced product and additional oil production. At the same time, an increase in the size of the radiator itself and the depth and diameter of the longitudinal cylindrical blind holes in its ends above the values indicated above leads to a decrease in the reliability of the claimed technical solution due to the possibility of destroying the radiator with an increase in the parameters of the longitudinal cylindrical blind holes, as well as the possibility of damage to the casing string with an increase in the dimensions of the emitter itself. The maximum immersion depth was 1350 m. The effect of the impact usually manifested itself 7-15 days after it began in the form of a decrease in the water cut of the extracted product and additional oil production. As a result of three impact cycles lasting 3-5 weeks, the water cut of the production as a whole in the area of the field decreased from 95.8 to 91.5%. Also, the alternation of shock-wave action for seven days with a break of seven days in two months more than doubled the debit of the well cluster, which led to an increase in production by 40,000 tons of oil.

Thus, by using the emitter to create a wave disturbance on heavily watered reservoirs of an oil field, a complex rehabilitating effect is exerted, reaching several kilometers, not only on the well, but also on the field as a whole.

It should be understood that the preferred embodiments of the invention described above by way of example do not limit its scope. After reviewing this description, those skilled in the art may propose many changes and additions to the described embodiments, all of which will fall within the scope of the utility model's patent protection as defined by its claims.

Claims (1)

An emitter for creating a wave disturbance on heavily watered reservoirs of an oil field, containing a striker having a cylindrical body, characterized in that the striker is made with the possibility of mounting on the lower end section of the drill pipes freely suspended in the well casing, in the lower and upper ends of the striker there are longitudinal cylindrical blind holes, and a chamfer is made on the lower end of the striker, while the striker is made with the possibility of reciprocating movement inside the casing pipe to provide impact on the flat disk located at the bottom of the casing pipe at the interface between the phases of the productive formation and the bedrock in such a way as to ensure the transformation kinetic energy of drill pipes freely suspended in the casing pipe into waves passing through the phase separation of the productive formation and bedrock, while the length and diameter of the cylindrical body of the striker are 1200 mm and 200 mm, respectively, and the depth and diameter of the longitudinal cylindrical The deep blind holes in the ends of the cylindrical body of the striker are 350 mm and 25 mm, respectively.

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