RU2513961C1 - Procedure for survey of multi-hole horizontal well - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention suggests procedure for survey of the multi-hole horizontal well that includes stages of bottomhole apparatus running-in to the well, performance of hydrodynamic research and removal of a geophysical tool from the multi-hole horizontal well. At that, before bottomhole apparatus running-in, at the head of the multi-hole horizontal well a hydraulic whipstock with drill out breakable cap, metering orifice and fixing breaking pin is installed at the lower end of the pipe string. The pipe string with the hydraulic whipstock is run in with simultaneous washing up to space of the surveyed side-tracking. Herewith in process of running-in the pipe string is equipped with kick-off valves. Then excess hydraulic pressure is created in the pipe string and the string is run in into the surveyed offshoot and excess pressure in the pipe string is increased till the breaking pin is destructed and the breakable cap is disconnected from the hydraulic whipstock. Then at the well head the bottomhole apparatus is connected to a rigid cable and the apparatus is run in into the pipe string until it leaves the string and appears in the offshoot. Thereafter fluid influx is stimulated from the stratum by gas injection to tubing-casing annulus through kick-off valves and hydrodynamic research is carried out in the surveyed offshoot by the bottomhole apparatus pushing up to the bottomhole. After hydrodynamic research the rigid cable with bottomhole apparatus from the pipe string and the pipe string with hydraulic whipstock are removed in sequence.

EFFECT: improving accuracy and efficiency of hydrodynamic research in offshoots of the multi-hole horizontal well.

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Description

The invention relates to the oil industry and can be used in hydrodynamic studies of multilateral horizontal wells.

There is a method of hydrodynamic research of horizontal wells, (Osadchiy V.M., Teleshkov V.M. Status and prospects of development of technology for researching horizontal wells during testing and operation. Scientific and technical bulletin "Karotazhnik", 2001. P.107-119), including placement of instrumentation at the end of the string of flexible pipes, within which a geophysical cable is passed, pushing the flexible pipes into the horizontal wellbore, pumping fluid or gas through the cavity of the flexible pipes, and conducting research.

The disadvantage of this method is the inability to conduct research in multilateral horizontal wells due to the inability to get into the sidetracks of these wells.

A known method of hydrodynamic research of horizontal wells (patent RU No. 2243372, IPC ЕВВ 47/00, published in Bulletin No. 36 on December 27, 2004), which includes exciting the well, measuring parameters using downhole tools located on horizontal sections of the well with various geophysical characteristics, and processing the measurement results, while before conducting research on the tubing string, containers are placed that represent sections of the pipe on which slots are cut. Depth autonomous devices are installed inside the containers, the tubing string is lowered into the well, a sucker rod pump is installed in the vertical part of the well in the tubing string, below which a filter is placed from the perforated pipe section of the tubing string, through slots in the containers and through the filter passes the well fluid to the intake of the pump through the tubing string and along the annulus, while the wells are excited by the same pump.

The disadvantages of this method are:

-firstly, the method does not allow the study of multilateral horizontal wells due to the impossibility of getting into the lateral shafts of multilateral wells;

-secondly, deep autonomous devices are installed inside containers, which reduces the accuracy of measurements and distorts the results of studies;

thirdly, the limited functionality of deep autonomous devices.

Closest to the invention in technical essence is a method for investigating a multilateral horizontal well (patent RU No. 2394985, IPC ЕВВ 47/00, published in Bulletin No. 20 07/20/2010), including the placement of deep-well instruments measuring pressure and temperature, in the main wellbore before and after entering the lateral wellbore, descent into the well of a string of pipes with a downhole pump, developing the well in stable mode, shutting the well and determining the pressure recovery curve, putting the well into operation, increasing or decreasing flow rate with respect to the stub flax debit, withdrawal wells in a stable regime, constant pressure and temperature measurement and making conclusions on the intensity of each sidetrack inflow based on the data on the amplitude of temperature change on the newly established steady state.

The disadvantages of this method are:

- firstly, during the study of a multilateral well, the deep-well instruments, measuring pressure and temperature, are placed in the main well before and after entering the lateral well, while it is almost impossible to get the deep-well tool into the specified lateral well;

secondly, a large number of measuring instruments installed in the well complicate the implementation of the method;

thirdly, low accuracy of measurements, since pressure and temperature measurements are made in statics, and deep-well instruments are placed in certain intervals of a multilateral horizontal well;

fourthly, when watering a multilateral horizontal well, there is no need to study the main well, since the source of watering is the lateral well, therefore the issues of getting into a given well and conducting hydrodynamic research (thermometry, flow rate (inflow) with determining the lateral watering interval are becoming relevant) trunk);

fifthly, when implementing the method, deep autonomous devices are installed inside containers, which reduces the accuracy of measurements and distorts the research results.

The technical objectives of the proposal are to increase the accuracy and efficiency of hydrodynamic studies in the sidetracks of a multilateral horizontal well due to the selective penetration into them with the possibility of subsequent movement of the downhole tool along the entire length of the studied lateral trunk of a multilateral horizontal well.

The stated technical problems are solved by the method of investigating a multilateral horizontal well, including the descent of a deep instrument into the well, conducting hydrodynamic studies, and extracting a geophysical instrument from a multilateral horizontal well.

New is that when examining a multi-hole horizontal well, a hydraulic diverter is used, and an easily drilled whipping nozzle with a calibrated hole is installed on its lower end and fixed with a shear pin, a hydraulic diverter is installed on the mouth of a multi-hole horizontal well at the lower end of the pipe string, then the pipe string is lowered with hydraulic diverter with simultaneous flushing to the interval of the cutoff of the investigated lateral barrel, and during the descent of the columns at the pipes, they are equipped with start-up valves, create excess hydraulic pressure in the pipe string and lower it into the studied lateral barrel of a multilateral horizontal well, increase the pressure in the pipe string until the shear pin is destroyed and the whip nozzle is disconnected from the hydraulic deflector, then the downhole device is connected to the wellhead with a hard cable, lower the depth device with the hard cable into the pipe string until the device exits the pipe string and places it in the studied lateral trunk, cause ok liquid from the reservoir by injecting gas into the annular space through the start-up valves, conduct hydrodynamic studies in the studied lateral well by pushing the deep-well tool to its bottom, after conducting hydrodynamic studies, remove the hard cable with the deep-well device from the pipe string, then remove the pipe string from the horizontal well with a hydraulic diverter, during hydrodynamic studies of other lateral shafts of a multilateral horizontal well operation, is described s above was repeated.

1 and 2 schematically depict the proposed method for the study of multilateral horizontal wells.

The proposed method is as follows.

Multilateral horizontal well 1 (see figure 1) has sidetracks 1 'and 1 ”(see figure 1). During operation of a multilateral horizontal well, a breakthrough of water from the formation into its lateral shafts is possible. To determine the watering intervals, a multilateral horizontal well is examined.

For example, a multi-hole horizontal well 1 was cased with a production string with a diameter of 168 mm and a length of 1340 m. Several open sidetracks 1 'and 1 ”with a diameter of 124 mm were drilled from a multi-hole horizontal well 1. Each of the side trunks 1 'and 1 ”has its own bottom depth.

To determine the waterlogging intervals of the sidetracks, a sequential hydrodynamic study of the sidetracks 1 'and 1 ”or a selective hydrodynamic study of one of the trunks - 1' or 1” is carried out, if it is known which of these sidetracks is flooding. For example, hydrodynamic studies begin with a sidetrack 1 'in a multilateral horizontal well 1 having a bottom depth of 1185 m.

For this purpose, a hydraulic diverter 3 is installed at the mouth of a multi-hole horizontal well 1 at the lower end of the pipe string 2, which ensures that the pipe string 2 enters the sidetrack under study, for example, a trunk 1 'of a multi-hole horizontal well 1. For research, use a hydraulic diverter 3. As a hydraulic diverter 3 they use devices widely used by OAO TATNEFT for flushing and acidizing multilateral wells, for example, those described in patents RU No. 2318111, IPC Е21В 23/00, op off 02/27/2008, or No. 2318112, IPC Е21В 23/00, publ. 02/27/2008 in bull. No. 6. The hydraulic diverter 3 is provided with a rod 3 '(see figure 2).

Install on the lower end of the hydraulic diverter 3 easily drilled whipping nozzle 4 with a calibrated hole 5 and fix it with a shear pin 6.

As the string of pipes 2 can be used, for example, a string of tubing with a diameter of 73 mm according to GOST 633-80.

The whipping nozzle 4 (see Fig. 1) is made of easily drilled material, for example, grade Amg6 according to GOST 4784-97.

The diameter of the calibrated hole 5 is determined empirically at the laboratory bench, taking into account the diameters of the pipe string 2 and hydraulic diverter 3, overpressure, fluid flow. For example, the diameter of the calibrated hole 5 is 4.0 mm.

As a shear pin 6 are used, for example, three screws with a diameter of 7 mm, made of steel grade 45 and collapsing under excessive pressure in the pipe string 2, for example, 15 MPa.

By supplying the process fluid to the pipe string 2 by the pumping unit and the process fluid exiting through the annulus 7, the pipe string 2 with a hydraulic diverter 3 is lowered to the cut-off interval 8 of the investigated side trunk 1 ', which is in the interval, for example, 975 m. Moreover, during the descent, the pipe string equipped with start-up valves (not shown in FIGS. 1, 2), for example, with three start-up valves in the range of 500, 650 and 800 m.

The calibrated hole 5 allows you to flush a multilateral horizontal well 1 during the descent of the device into the well and prevents jamming and sticking of the hydraulic diverter 3 during tripping.

An excess hydraulic pressure is created in the pipe string 2, for example 6.0 MPa, and the pipe string 2 is lowered into the lateral shaft G under study (see FIGS. 1 and 2) of a multilateral horizontal well 1.

The descent of the pipe string 2 (see FIG. 1) with a hydraulic diverter 3 into the studied lateral barrel 1 ′ is carried out due to the deviation of the rod 3 ′ of the hydraulic diverter 3 towards the side barrel 1 ′ under the action of overpressure.

After getting the pipe string 2 (see Fig. 1) with a hydraulic diverter 3 into the studied lateral shaft G, the excess pressure in the pipe string 2 is increased until the shear pin 6 is destroyed and the knockout nozzle 4 is disconnected from the hydraulic diverter 3. For example, when excess pressure 15 is reached , 0 MPa created by the pumping unit, the shear pin 6 is destroyed, and the whip nozzle 4 is disconnected from the hydraulic diverter 3 and falls into the studied lateral barrel 1 '.

The hydraulic diverter 3 due to getting into the lateral well guarantees the subsequent delivery of the downhole tool to the specified lateral well of the multilateral well.

Next, at the mouth of a multilateral horizontal well 1, a deep (geophysical) device 9 (see FIG. 2) is connected to a rigid cable 10.

As a depth device 9 for conducting hydrodynamic studies of the lateral shafts 1 'and 1 ”of a multilateral horizontal well 1, a geophysical device of any known design is used, for example, a complex device of the modular type GDI-7 manufactured by Tatneftegeofizika-Universal LLC (Tatarstan, Bugulma ), designed for hydrodynamic studies in open trunks of horizontal wells. This geophysical instrument provides for conducting geophysical studies, for example, measuring temperature and flow rate (inflow) with the determination of the watering interval as it moves along the sidetrack 1 'of a multilateral horizontal well 1.

The inner bore diameter D of the hydraulic diverter 3 is selected depending on the outer diameter d of the downhole tool 9, and the bore diameter D of the hydraulic diverter 3 should be larger than the outer diameter d of the downhole device 9 (D> d) with the possibility of passing the downhole device 9 through the hydraulic diverter 3. For example, the outer diameter d of the depth tool 9 is 45 mm, then the inner bore diameter D of the hydraulic diverter 3 is 55 mm.

As a rigid cable 10, for example, a cable of variable cross-section of grade KL 3-160 / 230-90Oa (with a diameter of 22-28 mm) or a cable of constant cross-section (diameter 28 mm) of grade KG 3 × 0.75-150-150 Oa, manufactured by TISpribor-M CJSC (Russia, Pskov, Almaznaya St., 3).

A rigid cable 10 with a downhole tool 9 at the end is lowered into the pipe string 2 until the downhole tool 9 exits the pipe string 2 and is placed in the studied side trunk 1 '. Then, an inflow of fluid from the formation is caused by gas injection into the annular space through the start valves (not shown in FIGS. 1 and 2). For example, a nitrogen compressor is injected into the annulus of the well with a nitrogen compressor, while the start valves on the pipe string 2 are opened, the well fluid from the annulus of the well flows into the pipe string 2, and fluid flow from the multilateral horizontal well 1 is called up, which allows hydrodynamic investigations in the sidetrack 1 'of a multilateral horizontal well 1.

By pushing the depth tool 9 through the rigid cable 10 to the bottom 11, for example, to the interval 1185 m of the investigated side trunk 1 ', hydrodynamic studies are carried out in the side trunk 1'.

As a result of hydrodynamic studies, the presence or absence of a watering interval in the lateral trunk 1 ′ is determined. For example, an irrigation interval of 1020-1062 m was determined (not shown in FIGS. 1 and 2).

The rigid cable 10 due to its stiffness allows you to effectively push the deep tool 9 to the bottom 11 of the investigated side trunk 1 'and to perform a hydrodynamic study of the side trunk 1' in dynamics, which significantly increases the accuracy of measurements in contrast to measurements in statics, as indicated in the prototype method.

After conducting hydrodynamic studies, the deep device 9 is removed with a rigid cable 10 from the pipe string 2.

Then, a pipe string 2 with a hydraulic diverter 3 is removed from the multilateral horizontal well 1.

For hydrodynamic studies in a 1 ”sidetrack, the above operations are repeated: from installing an easily drilled whip nozzle 4 with a calibrated hole 5 on the lower end of the hydraulic diverter 3 and until the pipe string 2 with hydraulic diverter 3 is removed from the 1” sidetrack of a multilateral horizontal well 1.

Thus, the presence or absence of watering intervals in the lateral well 1 ”of a multilateral horizontal well 1 is determined.

According to the results of studies of a multilateral horizontal well, waterproofing works are carried out to cut off the watering intervals of the lateral shafts of the multilateral well 1.

The implementation of the proposed method allows you to accurately determine the watering intervals of the lateral shafts of a multilateral horizontal well.

In the process of conducting hydrodynamic studies in the lateral shafts of a multilateral well, the downhole tool is in direct contact with the walls of the lateral shafts of the multilateral well, which makes it possible to increase the efficiency of hydrodynamic measurements and thereby determine the water-flooding intervals of the lateral shafts of the multilateral well and to measure the intensity and composition of the flow.

The proposed method for investigating a multilateral horizontal well allows increasing the accuracy and efficiency of hydrodynamic studies in the lateral trunks of a multilateral horizontal well due to the selective penetration of multilateral horizontal wells into the lateral trunks with the possibility of subsequent movement of the downhole tool along the entire length of the studied lateral trunk of a multilateral horizontal well.

Claims (1)

A method for investigating a multilateral horizontal well, including a descent into the well of a downhole tool, conducting hydrodynamic studies, extracting a geophysical instrument from a multilateral horizontal well, characterized in that that when examining a multilateral horizontal well, a hydraulic diverter is used, and an easily drilled whipping nozzle with a calibrated hole is installed on its lower end and fixed with a shear pin, a hydraulic diverter is installed on the mouth of a multilateral horizontal well at the lower end of the pipe string, then the pipe string with hydraulic diverter is lowered simultaneously washing to the cutoff interval of the investigated sidetrack, and during the descent, the pipe string is equipped with valves, create excess hydraulic pressure in the pipe string and lower it into the studied lateral trunk of a multilateral horizontal well, increase the pressure in the pipe string until the shear pin is destroyed and the whip nozzle is disconnected from the hydraulic deflector, then the downhole device is connected to the rigid cable at the wellhead, the downhole device with a rigid cable is lowered into the pipe string until the device exits the pipe string and is placed in the side wall under study, causing fluid to flow from the pipe a hundred gas injection into the annular space through the start-up valves, hydrodynamic studies are carried out in the studied lateral trunk by pushing the deep-well device to its bottom, after the hydrodynamic studies, the hard cable with the deep-well device is removed from the pipe string, then the pipe string with hydraulic deflector is removed from a multilateral horizontal well, in hydrodynamic studies of other lateral shafts of a multilateral horizontal well, the operations described above are repeated .

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