RU2471984C2 - Device for hydrodynamic monitoring of wells - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: device comprises a tight body suspended on a geophysical cable, where a motor is installed, as well as an electromechanical packer connected to it by means of a screw gear and a controlled valve device. At the same time the device is additionally equipped with a switching unit, installed above the electric motor, an anchor installed above the electromechanical packer, two pressure compensators, one of which is installed above the anchor, and the second one is installed below a balancing valve, a tip of a cable head installed in the lower part of the device, and a remote well tool fixed to the tip of the cable head. Besides, the switching unit and the electric motor are arranged in a tight body.

EFFECT: higher reliability of tight closure of tubing string cavity and provision for possibility to efficiently monitor pressure change when operating in wells in a depression mode.

2 dwg

Description

The device for hydrodynamic monitoring of wells is designed for hydrodynamic studies of wells in a depressed mode, namely, to tightly shut off the internal cavity of a tubing string to record the pressure recovery curve (HPC) of a formation using remote geophysical instruments to quickly determine the hydrodynamic parameters of the formation.

A device for hydrodynamic research of wells (RU, patent No. 2199009, E21B 49/00, 2003), containing a packing device, a depression chamber with atmospheric pressure to create fluid flow from the reservoir and formed by a set of tubing with a valve system, a sealed sampler and remote pressure sensors to monitor the entire process of hydrodynamic testing. The device descends into the well on a geophysical cable, and the packer and valve system of the depression chamber are controlled by one electro-hydromechanical drive.

The known device provides interval testing of the production casing, a multi-cycle depressive and repressive effect on the treated formations with PZP cleaning with extraction of the cleaning products to the surface, as well as testing productive formations with a one-packer arrangement of equipment with registration of pressure transducer and issuing hydrodynamic parameters and taking sealed samples.

A known method and device for controlling the quality of fluid pumping by analyzing the flow rate of fluid from the rock (RU, patent 2349751, E21B 49/08, 2009). The device comprises a cable-lowered device equipped with an anchor, two packers for separating the annular space of the well with the formation of the upper annular space, a hermetically insulated middle annular space and the lower annular space. The device is also equipped with a sealing shoe with a hydraulic channel that can selectively extend, a circulation valve above the top packer and a balancing valve located in a sealed middle annular space. The device includes a telesystem, a data transmission unit in the form of a downhole controller and processor, and an energy source to provide two-way communication with the surface and power supply to the deep components.

The known method and device solve the problem of controlling pressure changes during the well testing, as well as increasing the reliability of the analysis of the rate of formation fluid inflow, its compressibility and mobility parameters.

A known device for crimping and researching wells (RU, patent No. 2339811, E21B 47/00, 2008), comprising a housing suspended on a cable-rope, in which sensors of fluid hydrodynamic parameters are installed with a processing unit and outputting the research results in real time, an electric motor, an electromechanical packer with controlled valves, a flow meter and a pressure gauge mounted on the supply line of the working fluid into the well.

The device has a high resolution of measurement of the hydrogeological parameters of the well under study and provides control of the differential pressure under and over the packer with the issuance of measurement results of controlled parameters in real time. The device is effective when working in deep wells with low pressure.

The disadvantages of the known devices include the complexity of the design, as well as difficulties in practical implementation and limited use. Namely:

- for lowering the device into the well on a geophysical cable in known devices, it is necessary to first carry out preparatory steps for killing the well, extracting the tubing from the well, cleaning the column walls in the packing interval, which leads to additional time and production costs;

- for separating the casing string in known devices, large-sized packing elements are used, for which a mechanical compressive load is transmitted to which it is necessary to supply a high supply voltage to the electric drive. This, in turn, is reflected in the special requirements for the selection of a powerful ground-based power source and a geophysical cable with a large cross-section of wire strands, while the length of such a geophysical cable is limited by the dimensions of the logging drum, and the depth of the device is accordingly limited;

- the diameter range of the studied wells is limited by the diameter of the packers of known devices and the length of the entire complex as a whole.

The objective of the present invention is to provide a multifunctional mobile device that ensures the reliability of a tight shutoff of the tubing cavity and the operational control of pressure changes when working in wells in a depressed mode.

The problem is solved as follows.

In a device for hydrodynamic monitoring of wells, comprising a housing suspended on a geophysical cable, in which a block of sensors for hydrodynamic parameters of the fluid, an electric motor connected to the electric motor via a helical transmission, an electromechanical packer, and a controllable valve device according to the invention are excluded; the device is additionally equipped with a switching unit installed above the electric motor, an armature installed above the electromechanical packer, two pressure compensators, one of which is installed above the armature, and the second is installed below the equalizing valve, and a cable head lug mounted at the bottom of the device. Moreover, the switching unit and the motor are housed in a sealed enclosure.

In contrast to the known analogues, the proposed device for hydrodynamic monitoring of wells has the following advantages:

- the exclusion of fluid hydrodynamic parameters from the housing of the sensor block of sensors makes it possible to significantly reduce the overall dimensions of the body, which makes it possible to use the proposed small-sized device for multiple well closure to isolate the study interval of cased wells of various diameters equipped with a tubing string and production packer, and the presence of an additional cable head tip in the bottom parts of the device provides the ability to connect to it as needed various geoph izicheskikh field devices operating on logging geophysical cable;

- the presence of the switching unit provides remote control of the motor, and, accordingly, the opening and closing of the packer with an anchor, which increases the efficiency of managing the operation of the proposed device;

- the placement of the electric motor with the switching unit in a sealed enclosure provides isolation of the current-carrying element, device from an aggressive well environment, thereby increasing the reliability and life of the proposed device;

- the presence of the anchor in the structure provides centering of the packer, evenly distributing the deformation of the overlapping element of the packer around the circumference, and also increases the reliability of fixing the proposed device in the tubing cavity or in the well, preventing its movement when excessive pressure occurs in the pipe or sub-packer cavity of the well;

- the presence of pressure compensators allows the use of a small-sized electromechanical drive in the design, thereby reducing the overall dimensions of the proposed device as a whole and making it possible to use the proposed device for monitoring wells with high overpressure.

If there is a combination of these features, the proposed device

- can be used for remote registration of HPC at the time of stopping of the pumping units with the help of a depth gauge connected to the housing through the tip of the cable head at the bottom of the device;

- can be used to take representative samples of the formation fluid when closing the well on the high-pressure field using an in-depth sampler attached to the tip of the cable head in the lower part of the body;

- in combination with remote downhole tools connected to the tip of the cable head in the lower part of the device (and / or to the cable head of the upper part of the body), it can be used for hydrodynamic studies and / or geophysical well logging;

- simplicity of design, low power consumption, protection of current-carrying elements of the proposed device provide the manufacturability of its manufacture and the reliability of practical use.

Figure 1 shows a design diagram of a device for hydrodynamic monitoring of wells.

Figure 2 shows a variant of the layout of the device for hydrodynamic monitoring of wells during the registration of the KVD.

A device for hydrodynamic monitoring of wells (hereinafter the device) comprises a sealed housing 2 lowered on a geophysical cable 1, with a switching unit 3 and an electric motor 4 with a planetary gear 5, a screw 6 and a nut 7, forming a screw pair for converting the rotational moment of the electric motor 4 into axial force, the central rod 8 connected to the nut 7 in the upper part, and in the lower part connected to the pusher 9, the packer 10, the armature 11 and the balancing valve 12 with o-rings 13. The central rod 8 is supplied pressure compensators 14 and 15. The apparatus is provided with a standard instrument docking head 16 installed in the upper housing portion 2 and the standard tip of cable head 18 installed in the lower part of the device.

The docking instrument head 16 serves to attach the device to the tip 17 of the geophysical cable 1 and provides a contact connection of the veins of the geophysical cable 1 with the electrical leads of the switching unit 3 and the transit wires 19 from the tip of the cable head 18. The switching unit 3 provides remote control of the motor 4 which is the work of the packer 10, and mechanically connected to it anchors 11.

During the operation of the device, the packer 10 provides a tight overlap of the tubing cavity. The anchor 11 thus centers the device as a whole and fixes it by means of dies 20, preventing the device from moving under the influence of excessive pressure below the overlap interval. Compensators 14 and 15 hydraulically balance the compressive effect of hydraulic pressure from the liquid column on the central stem 8, coupled with the body 2 and the pusher 9. The equalizing valve 12 provides pressure equalization between the isolated intervals of the tubing when closing the packer 10.

A device for hydrodynamic monitoring of a well works as follows.

To monitor the KVD during the development and / or research of a depression well, located on the drum 22 of the logging tool, cable 1 is joined to the instrument head 16 of the device for hydrodynamic monitoring of wells (hereinafter the device) by means of a tip 17 of a geophysical cable 1. At the same time, to the tip of the cable head 18 connect the pressure gauge 21. The layout is lowered into the tubing string 24, equipped with an operational packer 25. Upon reaching a predetermined depth, the control current is supplied through the geophysical cable 1 to the position Yelnia polarity switching unit 3, whereby through the helical gear motor 4 there is an opening of the armature 11, dies 19, which are put forward up to the stop in the tubing wall. After the anchor 11 is opened, the packer 10 is opened. The opening limit of the packer 10 is controlled by an ammeter 26 of the ground power supply 27, which first shows the idle current of the gearbox of the electric motor 4, and then the final load on the packer element (rubber cuffs are not shown in FIG.) Of the packer 10 .

After the packer 10 is opened, fluid flow to the well is stopped. According to the operational data, the change in the level of the liquid column above the isolated interval from the device 23 and according to the operational data, the pressure changes in time below the isolated interval from the pressure gauge 21, the tightness of the insulation of the tubing cavity is determined. The parameters of the pressure recovery curve in the under-packer space are recorded with a pressure gauge 21.

The hydrodynamic parameters of the reservoir are determined by the inflow curve and the reservoir pressure recovery curve over time by the ground recorder 28, and the operator decides to continue or stop the work to call the inflow from the reservoir or to take measures to influence the bottom-hole formation zone in order to intensify the inflow.

At the end of the measurement and recording, a negative polarity current is supplied to the switching unit 3 of the device, as a result of which the electric motor 4 changes the direction of rotation of the electric drive. The rubber cuffs of the packer 10 and the dies 20 of the anchor 11 are forcibly returned to their original position by means of a screw transmission. Packer 10 closes. This opens the equalizing valve 12, equalizing the pressure above and below the device. Ammeter 26 of the power supply 27 controls the change in current, and when the current value reaches zero, the power supply 27 is turned off. The assembly is removed from the well to the surface.

Depending on the task, instead of a pressure gauge 21, a complex downhole tool can be connected to which, as necessary, a signal is supplied, for example, for sampling formation fluid.

In addition, depending on the tasks to be solved, the proposed device can be docked with a complex downhole tool and / or depth gauge or with two complex downhole tools by means of a docking tool head 16 and / or cable head 18 in any order, taking into account that the upper the integrated downhole tool will be equipped with bushing wires for transmitting signals to ground equipment.

Thus, the proposed device for hydrodynamic monitoring of the well

- has wider functional capabilities compared with known similar devices, is characterized by high reliability of barrel isolation, simplicity and small design dimensions,

- provides the removal of the pressure recovery curve (HPC) when closing the well at the bottom, which contributes to the selection of the optimal mode for further operation of the well and the qualitative determination of the hydrodynamic parameters of the formation

- can be used as an independent module for simultaneous and separate operation of several production and / or injection facilities (reservoir, interlayers) of one fountain, gas lift, pump, piezometric or injection wells.

Claims (1)

A device for hydrodynamic monitoring of wells, comprising a housing suspended on a geophysical cable, in which an electric motor is placed, an electromechanical packer connected to it by a helical transmission and a controlled valve device, characterized in that the device is additionally equipped with a switching unit mounted above the electric motor, an anchor mounted above the electromechanical packer, two pressure compensators, one of which is installed above the armature, and the second is installed below equal of the valve, the tip of cable head installed in the lower part of the device, and a remote downhole tool, attachable to the tip of cable head, wherein the switching unit and the electric motor are arranged in a sealed housing.

Images