Method for determining behind-casing flows

FIELD: oil and gas industry.

SUBSTANCE: the method is realized in two stages. At the first stage to the lower horizontal producer a flow string is run in to the beginning of a slotted filter. A heat insulated filter is set in the upper horizontal injector above the slotted filter. In the upper horizontal injector temperature tests are made in the interval from the well head up to the packer. Steam is injected to the lower horizontal producer and temperature tests are made simultaneously in the upper horizontal injector. Upon completion of steam injection to the lower well the final temperature test is made in the upper well. At the second stage fresh water is injected to the upper horizontal injector and a heat insulated flow string is run in with a thermal packer and shank. The packer is set before the slotted filter and control temperature test is made in tubular annulus in the interval from the well head up to the packer. Steam is injected to the upper horizontal injector though the heat insulated flow string, through the packer and shank to the beginning of the slotted filter. At that, periodically, upon commencement of injection, temperature tests are made in tubular annulus in the interval from the well head up to the packer. Upon completion of steam injection the final temperature test is performed in the upper horizontal injector. When required, tests in the lower producer and operational procedures for the wells are interchanged.

EFFECT: improving authenticity of the obtained results during identification of intervals with cross flows behind the casing for wells operated in deposits of viscous and superviscous oil.

 

The invention relates to the oil industry and can be used to determine the intervals of the well casing with the fluid motion.

There is a method of defining annular flow of fluid Method is based on the series of thermal images directly after putting the well into operation, and on the availability of annular fluid motion is judged by the increased pace of the establishment of thermal field (USSR Author's certificate No. 665082, CL EV 47/06, publ. 30.05.1979).

The closest to the proposed invention the technical essence is the way active thermometry existing wells, offering a series of temperature measurements with subsequent comparison of the obtained infrared images during operation of the well. Register thermograms before and after short-term local heating of the casing in the expected range of motion of the fluid. On the nature of the motion of the fluid is judged by the rate of temperature increase. According to the second variant of the invention the registration of change of temperature is carried out in a period of time at a certain depth of the studied interval after a brief local heating of the casing at some distance in depth from the temperature sensor. On the nature of the motion of the fluid is judged by the rate of temperature increase (RF patent No. 2194160, CL EV/06, publ. 10.12.2002 - prototype).

A common disadvantage of the known technical solutions is the low reliability of results obtained when determining the intervals in the annular area of the fluid of the wells that are operated on deposits of viscous and viscous oil.

In the proposed invention solves the problem of increasing the reliability of the obtained results in the determination of the intervals in the annular area of the fluid of the wells that are operated on deposits of viscous and viscous oil.

The task is solved in that in the method of determining the annulus circulation, including studies thermometry wells and analysis of the results, according to the invention, in the case of the Deposit of viscous or viscous oil lower horizontal producer well and the upper horizontal injection wells located in a vertical plane and provided with a slotted filters in horizontal wells, the casing defining circulation carried out in two stages, the first stage in the lower horizontal production well down the string of tubing at the beginning of the slotted filter in the upper horizontal injection well down and make a landing insulated packer 20 m above the slotted filter at the top horizontal injection well with offline viscotemp Turnovo logging tool in a flexible pipe conducting a study of temperature in the interval from the wellhead to the packer, inject steam into the lower horizontal production well and at the same time in the upper horizontal injection wells periodically conduct studies of the temperature upon completion of the steam injection in the lower horizontal production well to produce a final study of the temperature in the upper horizontal injection well, in the second stage of the upper horizontal injection well pump fresh water and go down the column insulated tubing with heat-resistant packer and liner, make installation of the packer before the slot filter, the annular space between the wellhead to the packer using a stand-alone high-temperature logging tool in a flexible pipe hold-control study of temperature, inject steam into the upper horizontal discharge well the column insulated tubing through the packer and liner at the beginning of the slotted filter, while using a stand-alone high-temperature logging tool in a flexible pipe periodically conduct studies of the temperature in the annular space between the wellhead to the packer, upon completion of the steam injection conduct the final examination of the temperature in the upper horizontal magnetotail the Noah well, compare research results and make a conclusion about the presence or absence of annulus circulation, if necessary, investigation of the lower horizontal production wells order in the wells of changing places.

The invention

Research annular fluid motion dedicated a lot of work, but they all focus on research in the wells on the fields of light or low viscosity oil. However, such studies on the wells on the fields viscous or viscous oil, is almost impossible, since in this case there are conditions in which conventional research is impossible, in particular, high temperature wells, well locations and the modes of their operation. A common disadvantage of the known technical solutions for applications in the fields of viscous or viscous oil is the low reliability of results obtained. In the proposed invention solves the problem of increasing the reliability of the obtained results in the determination of the intervals in the annular area of the fluid of the wells that are operated on deposits of viscous and viscous oil. The problem is solved as follows.

When defining annulus circulation in wells located on deposits of viscous or viscous oil, has a pair of wells consisting of a lower horizontal producer well and the upper horizontal injection wells, located in a vertical plane and provided with a slotted filters in horizontal wells. Defining annulus circulation is carried out in two stages. At the first stage in the lower horizontal production well down the string of tubing at the beginning of the slotted filter in the upper horizontal injection well down and make a landing insulated packer 20 m above the slotted filter. In the upper horizontal injection well with offline high-temperature logging tool attached to the end of the flexible pipe, conducting a study of temperature in the interval from the wellhead to the packer, thus inject steam into the lower horizontal production well and at the same time in the upper horizontal injection wells periodically conduct studies of the temperature. Upon completion of the steam injection in the lower horizontal production well to produce a final study of the temperature in the upper horizontal injection well. In the second stage of the upper horizontal injection well pump fresh water and go down the column insulated tubing with heat-resistant packer and liner, make installation of the packer before the slot filter, the annular space in INTA the shaft from the wellhead to the packer using a stand-alone high-temperature logging tool in a flexible pipe hold-control study of temperature, inject steam into the upper horizontal injection well through the column insulated tubing through the packer and liner at the beginning of the slotted filter. When using stand-alone high-temperature logging tool in a flexible pipe periodically conduct studies of the temperature in the annular space between the wellhead to the packer. Upon completion of the steam injection conduct the final examination of the temperature in the upper horizontal injection well. Compare research results and make a conclusion about the presence or absence of annulus circulation.

If necessary, research the lower horizontal production wells order in the wells of changing places.

Specific example

Spend the definition of annulus fluid circulation in a horizontal injection well, located on deposits of viscous oil.

On deposits of viscous oil posted a couple of wells. The lower horizontal production well and an upper horizontal injection wells are located in a vertical plane and provided with a slotted filters in horizontal wells. The distance between the horizontal trunks 5 meters

Defining annulus circulation on the horizontal injection well perform in Dr. who and the stage.

In the first stage, to determine whether interwell flow between two horizontal wells and casing circulation in injection wells, the lower horizontal production well down the column tubing with a diameter of 89 mm at the beginning of the slotted filter. In the upper horizontal injection well down and make a landing insulated packer PRO-YAMO-204 20 m above the slotted filter. In the upper horizontal injection well with offline high-temperature logging tool in a flexible pipe with a diameter of 38 mm are conducting a study of temperature in the interval from the wellhead to the packer. During the day pumped vapor with a flow rate of 80 t/day in the lower horizontal production well and at the same time in the upper horizontal injection wells periodically every 4 hours during the day doing research temperature. Upon completion of the steam injection in the lower horizontal production well to produce the final examination: the final logging - study of the temperature in the upper horizontal injection well.

In the second stage of the upper horizontal injection well pump fresh water and go down the column insulated tubing with a diameter of 89 mm, type thermocells with heat-resistant packer PRO-YAMO-204 and shank diameter 89 mm length 20 m Make installation of the packer before the slot filter, the annular space between the wellhead to the packer using a stand-alone high-temperature logging tool in a flexible pipe with a diameter of 38 mm teach-control study of temperature. To determine whether casing movement from the filter part up to the "complete care fluid"identified during the drilling of wells, pumping steam into the upper horizontal injection well through the column insulated tubing through the packer and liner at the beginning of the slotted filter during the day with a flow rate of 80 tons per day. When using stand-alone high-temperature logging tool in a flexible pipe with a diameter of 38 mm periodically every 4 hours after the start of pumping during the day doing research temperature in the annular space between the wellhead to the packer. The lower horizontal well at this time is idle. Upon completion of the steam injection conduct the final examination: the final logging - study of the temperature in the upper horizontal injection well.

Analysis of thermal images shows that in the depth interval 43-63 m is the distortion curves and increasing the temperature to 120 degrees, which is associated with the presence of killed circulation. Note the out of the way of research on the prototype did not reveal the presence of annulus circulation.

The application of the proposed method will allow to solve the problem of increasing the reliability of the obtained results in the determination of the intervals in the annular area of the fluid of the wells that are operated on deposits of viscous and viscous oil.

The method of determining the annulus circulation, including studies thermometry wells and analysis of results, characterized in that in the case of the Deposit of viscous or viscous oil lower horizontal producer well and the upper horizontal injection wells located in a vertical plane and provided with a slotted filters in horizontal wells, the casing defining circulation carried out in two stages, the first stage in the lower horizontal production well down the string of tubing at the beginning of the slotted filter in the upper horizontal injection well down and make a landing insulated packer 20 m above the slotted filter in the upper horizontal injection well with Autonomous high-temperature logging tool in a flexible pipe conducting a study of temperature in the interval from the wellhead to the packer, pump pairs in the lower horizontal production well and at the same time in the upper horizontal injection wells periodically Provo is Yat research temperature, upon completion of the steam injection in the lower horizontal production well to produce a final study of the temperature in the upper horizontal injection well, in the second stage of the upper horizontal injection well pump fresh water and go down the column insulated tubing with heat-resistant packer and liner, make installation of the packer before the slot filter, the annular space between the wellhead to the packer using a stand-alone high-temperature logging tool in a flexible pipe hold-control study of temperature, inject steam into the upper horizontal injection well through the column insulated tubing through the packer and liner at the beginning of the slotted filter, when this using a stand-alone high-temperature logging tool in a flexible pipe periodically conduct studies of the temperature in the annular space between the wellhead to the packer, upon completion of the steam injection conduct the final examination of the temperature in the upper horizontal injection well, compare research results and make a conclusion about the presence or absence of annulus circulation, if necessary, investigation of the lower horizontal is avivausa wells order in the wells of changing places.



 

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