RU2172826C2 - Method of research of running wells and device for its embodiment - Google Patents

Abstract

FIELD: oil producing industry, particularly, geophysical and hydrodynamic researches of running wells. SUBSTANCE: method includes measurement and registration of oil production rate and bottom-hole pressure by self-contained downhole instrument. Instrument is run into bottom-hole under conditions of free falling and retrieve from well by flow of ascending fluid acting on packer opened at required moment. Device for realization of claimed method has flexible sealing member with two branch pipes overlapping the side windows in instrument body. Packer drive is made in form of spring with retainer holding the packer in folded state up to moment of operation of electromagnetic triggering lock freeing the retainer. EFFECT: higher efficiency and reduced expenditures in research of running wells. 2 cl, 2 dwg

Description

 The invention relates to the oil industry and can be used in the study of existing wells.

 A known method of researching existing wells by the method of steady-state selection, by simultaneously measuring (and recording) bottomhole pressure and flow rate (productivity) of the well in several modes of its operation. At the same time, a self-recording (or remote) pressure gauge is lowered on the scraper wire to measure bottomhole pressure below the degassing point on the scraper wire. A well production rate is measured using wellhead flowmeter. Changing the operating mode of the well is usually carried out by changing the fitting installed on the flow line (pipe) / 1 /.

 The disadvantage of this method is the low accuracy of measuring the flow rate of the well. The main factor that distorts the readings of instruments for measuring the flow rate of a well is the time-varying gas content in the well’s production. Changing the operating mode (hence bottomhole pressure) of a well during research exacerbates the issue of accurately measuring the rate of well production.

 A known method of measuring the flow rate of producing wells, reducing the effect on the readings of the flow meter of the gas content in the product / 2 /. The essence of the method is that to measure the flow rate on the logging cable into the well below the degassing point, a downhole flowmeter with a turbine flow sensor is lowered.

 Thus, the measurement (and registration) of the well flow rate and bottom hole pressure is then performed using a complex downhole tool, lowered into the well using a wireline logging tool (or scraper wire, if the device has an autonomous readout recorder).

 The disadvantage of this method (and all known methods) of researching existing wells is the need to attract hoisting mechanisms for lowering and lifting the downhole tool.

 The purpose of this invention is to increase efficiency and reduce costs in the study of existing wells.

 This goal is achieved by the fact that in the method of researching existing wells by lowering an autonomous downhole tool with an electronic information storage device installed in the lubricator located at the wellhead and containing an upstream fluid flow sensor along the wellbore and a programmer with a timer that controls the operation mode of the device, to the limiter, which is below the point of oil degassing, measuring and recording flow rates according to a given program, and raising the device to the wellhead, launching an independent well the lighter device is carried out in free fall mode, the bottomhole pressure is additionally measured and recorded according to the specified program with the pressure sensor installed in the stand-alone borehole tool, after the measurements, the fluid flow is blocked by the packer installed in the stand-alone borehole tool, which is activated by an electrical signal from the programmer at a specified time, and carry out the rise of an autonomous downhole tool in the mode of its ascent to the mouth under the action of pressure on it from below.

 This allows you to conduct a well study without involving hoisting mechanisms, resulting in increased research efficiency and reduced costs.

 The device for researching existing wells contains an autonomous downhole tool, including a housing, an electronic information storage device, an upstream fluid flow sensor along the wellbore and a programmer with a timer that controls the operating mode, which is equipped with a packer with a drive and a bottomhole sensor for implementing the proposed method pressure placed in a sealed compartment of the housing, in which there are side windows for passing a fluid flow through a flow sensor, the packer made in the form of two nozzles with side windows worn on the casing and serving to overlap the side windows of the casing when the packer is triggered, and an elastic sealing element attached to the pipes from below and above and overlapping when the packer is activated, the annular space between the inner wall of the wellbore and the body of the downhole tool , and the packer drive is made in the form of an electromagnetic shutter, the winding of which is connected to the programmer, and a coil spring with a latch holding the packer in the initial state when the electromagnetic shutter releases.

 In FIG. 1 shows the device in the folded state of the packer, and FIG. 2 - the same, in the open state of the packer. In the sealed compartment of its housing are located: an electronic information storage device 1, a programmer with a timer 2, transducers 3 and 4 of the pressure sensor 5 and flow 6. The upper 8 and lower 9 nozzles are attached to the housing 7 of the device, to which an elastic sealing element 10 is attached.

 The spring 11 is used as a drive for opening the packer; it is held in a compressed state due to the latch with the dogs 12, which releases (releases the spring) when electric current is supplied to the electromagnetic shutter winding 13 with the armature 14 holding the dogs 12 in working condition when they are their tips installed in the annular groove A of the lower pipe 9.

 The device in the folded state of the packer is installed in the well’s lubricator and for research from the cavity of the lubricator is launched down the wellbore (along the tubing string). After the device reaches the limiter according to the specified program, the flow rate and pressure are measured and recorded. In this case, the windows B and B ^, B and B ^, made respectively in the housing 7 and the nozzles 8 and 9, are combined and the fluid flow is passed through the flow sensor 6.

 The change in the operating mode of the well is carried out at the same time at the wellhead by changing the fitting on the flow line.

 After completing a given measurement cycle, an electric current is supplied to the gate winding 13 at the command of the programmer and the armature 14 releases the dogs 12, as a result of which, under the action of the spring 11, the nozzles 8 and 9 with the sealing element 10 attached to them rush upward relative to the housing 7. This causes deformation elastic sealing element 10 until it stops against the borehole wall 15, overlapping windows B and C. Thus, the upward flow is blocked by the packer of the device and under the influence of the pressure drop I the device rises up to the lubricator.

 Decoding and processing of the results of the well research is carried out after removing the device from the lubricator according to the electronic information storage device.

 The list of figures - Fig. 1. The device in the folded state of the packer.

 FIG. 2. The device is in the open state of the packer.

 Sources of information.

 1. Vasilievsky V.N. Petrov A. I. "Study of oil wells and reservoirs." Ed. "The bowels", M. 1973

 2. The decision to grant a patent for the invention according to the application N 94020978/03 (0206680) dated 06.06.94, "Method for measuring the production rate of production wells." Applicant - Production Association Tatneft, authors: Gabdullin T.G., Muslimov R.X., Bogdanov X.U., Abdulkhairov R.M., Zalyaev 3.M.

Claims (2)

 1. A method of researching existing wells, including the descent along the wellbore installed in the lubricator located at the wellhead, of an autonomous downhole tool containing an electronic information storage device, an upstream fluid flow sensor along the wellbore and a timer programmer that controls the operation mode to the limiter, located below the point of gas degassing, measuring and recording flow rates according to a given program and raising the device to the wellhead, characterized in that the descent of an autonomous well about the device is carried out in free fall mode, the bottomhole pressure is additionally measured and recorded according to the specified program by the pressure sensor installed in the stand-alone downhole tool, after the measurements, the fluid flow is blocked by the packer installed in the stand-alone downhole tool that is activated by an electrical signal from the programmer at a specified time, and carry out the rise of an autonomous downhole tool in the mode of its ascent to the mouth under the action of pressure on it from below.  2. A device for researching existing wells, comprising an autonomous downhole tool, including a housing, an electronic information storage device, an upstream fluid flow sensor along the wellbore, and a programmer with a timer that controls the operating mode, which is equipped with a packer with a drive, located in its sealed compartment and a bottom hole pressure sensor located in a sealed compartment of the housing, in which side windows are made for passing a fluid flow through a flow sensor, the packer being made in the form of two x nozzles with side windows worn on the body and serving to overlap the side windows of the body when the packer is triggered, and an elastic sealing element attached to the nozzles from below and above and overlapping when the packer is triggered, the annular space between the inner wall of the wellbore and the body of the downhole tool, and the drive the packer is made in the form of an electromagnetic shutter, the winding of which is connected to the programmer, and a coil spring with a latch that holds the packer in its original folded state until the electromagnetic shutter releases.

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