RU37767U1 - DEVICE FOR DETERMINING THE OPTIMUM SUSPENSION PLACE OF THE INSTALLATION OF THE ELECTRIC CENTRIFUGAL PUMP IN CURVED WELLS - Google Patents

Description

2003125726

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E 21 at 47/022

DEVICE FOR DETERMINING AN OPTIMUM SUSPENSION PLACE

INSTALLATION OF ELECTRIC CENTRIFUGAL PUMP IN

CURVED WELLS

The device relates to the field of oil production using submersible pumps and is intended to select the optimal suspension area for the installation of an electric centrifugal pump (ESP) in wells with a curvature of the wellbore.

A known device for measuring the curvature of the wellbore by measuring the position of the meter in space - inclinometer, see the description of patent 2166084 RU, E 21 V 47/022 1.

The disadvantage of this device, like other inclinometers, is the low sensitivity and accuracy. So, the error in measuring the curvature of wells in modern inclinometer samples is of the order of ± 1.5 over a length of 10 meters, while the permissible bending of the ESP body does not exceed ± 3 (angular minutes) by 10 meters, see Installations of submersible centrifugal pumps for production oil. International translator. Ed. V.Yu. Aleksnerov et al., M., 1999, 611 p. 2.

Also known is a device for measuring the angle of inclination of a well according to patent No. 2018648 RU, IPC E 21 V 47/022 3, comprising a housing with upper and lower covers in which there is a sensing element in the form of a conical pendulum with an elastic base to which strain gauges are attached, outputs which are connected by cable to ground recording equipment.

The disadvantage of this device is the impossibility or low accuracy of measuring the bending of the body with a large ratio of its length to diameter.

A common disadvantage of these devices is that they are designed to measure the spatial position of the section of the well in which they are located. However, the optimal place for the suspension of the ESP in the well is one in which the bending of the ESP body, subject to other limiting conditions, for example, for medium pressure, temperature, etc., is the smallest. The calculation of the degree of the specified bending of the body, for example, through inclinometry data, is associated with a large volume of calculations and insufficient accuracy.

located outside the well and a cable connecting the output of the sensing element with the registration unit. Here, a laser and a receiving target (photocell) located at opposite ends of the housing are used as a sensitive element.

The disadvantage of this device is the need for the location of the receiving scaffold, at a distance not exceeding several body diameters from the laser. This makes the device unsuitable in cases where it is necessary to evaluate the bending of the ESP body, the length of which can reach several tens of meters and significantly exceeds its diameter. Another disadvantage of the device is that at great depths it is desirable to fill the cavity of the device with oil to protect it from penetrating into the cavity of the surrounding aggressive fluid under high pressure. In this case, the laser yarn in oil will be subject to scattering and the accuracy of the device will decrease sharply.

The technical problem solved by the proposed utility model is the ability to measure the bending of the ESP body in a curved well and, based on this, select the optimal ESP suspension point for its safe operation.

The problem is solved in that in the device containing the housing, the sensing element, the cable and ground-based data acquisition and processing equipment, an additional string, a metal disk, upper and lower string attachment points, a sensor unit and a measurement and data transmission unit are additionally introduced, and as the sensing element uses the specified string, mounted along the axis of the housing with the upper and lower nodes of the string and on which the metal disk is fixed so that its plane is perpendicular linear to the axis of the string, and a sensor block consisting of a base and four displacement sensors that are located crosswise around the perimeter of the specified base, and the sensor block is fixed in the cavity of the body so that the metal disk interacts with the sensors when the string is deflected, and the sensor outputs through the block measurement and data transmission connected to the cable.

The disk is made of ferromagnetic material, and the sensors are inductive displacement sensors.

Inductive displacement sensors are slotted with a slot, and the sensor block and the ferromagnetic disk are installed so that the plane of the disk enters the slots of these sensors.

For descent into the well, the device is attached to the pipe-compressor pipes (tubing), and the overall dimensions of the body and the elements of the housing to the tubing are chosen equal to the overall dimensions and similar to the mounting of an electric submersible pump, which is supposed to be used in this well.

The body cavity is sealed.

The body cavity is filled with oil, and a hydraulic compensator is attached to the body, the cavity of which communicates with the body cavity.

The measurement and data transmission unit contains the first and second subtraction units, the first and second multipliers, the adder, the square root calculation unit and the encoding and data transmission unit, moreover, the outputs of pairwise opposite sensors are connected to the inputs of the first and second subtraction units, and the outputs of the subtraction units are connected respectively, to the inputs of the first and second multiplier, the outputs of the specified cutters are connected to the inputs of the adder, and the output of the adder is connected to the input of the square root calculation unit, the output of which is through the block encoding and transmitting data is connected to the cable.

Due to the use of a string equal to the length of the body stretched along the body axis along the axis of the body and with a metal disc mounted on it, which interacts with four cross-shaped displacement sensors, it becomes possible to measure the deviations of the distance from the string to the inner surface of the body wall that appear when the latter bends . So, when the body bends about 3 by 10 meters, the middle part of the string deviates from the body wall by 10 meters by 2.18 mm, which can be easily measured, in particular, by an inductive slit sensor, the sensitivity of which is usually several micrometers. At the same time, to increase the sensitivity, it is advisable to make a metal disk of ferromagnetic material, and arrange it so that its plane enters the slots of all four sensors.

Due to the mounting of the device to the NTK in the same way as the mounting of a real ESP, and also due to the choice of the overall dimensions of the body of the proposed device equal to the overall dimensions of the ESP, which is supposed to be used in this well, the bending of the device casing in the sections of the curvature of the well is exactly equal to the bending of the real ESP on these same areas.

Ensuring the tightness of the cavity of the device’s case or making it oil-filled with the connection of the hydraulic compensator allows the device to be used at great depths and in aggressive liquids. In addition, the presence of oil in the slots of the sensors in which the metal disk also moves damps random vibrations and shocks of the specified disk when the device is lowered into the well and thereby increases the noise immunity of the measurements.

The use of a subtraction unit, a multiplier, an adder, a square root calculation unit, and a data encoding and transmission unit connected to the sensor outputs and a cable as described above in a measurement and data transmission unit, allows to obtain a signal at the output of the square root calculation unit, the magnitude of which depends only on the magnitude of the bend of the device’s body does not depend on which side the body bent. In addition, subtracting signals from opposite sensors can reduce measurement errors arising from common mode noise, such as temperature distortion of the characteristics of the sensors, and increase the sensitivity of the measurements.

Together, this increases the accuracy of measuring the degree of bending of the body of a real ESP at various points in a curved well. On the basis of this, it becomes possible to make a targeted choice of the most optimal ESP suspension area (flat; adki) for its safe operation. The choice of the suspension region in which the ESP bending is minimal allows, in particular, to reduce the vibration level during the operation of the pump and to eliminate the negative consequences associated with this, such as the destruction of the fasteners of sections, the lapels and flights of the ESP, to reduce the number of damage to the shafts and other structural elements and reduce their wear. In turn, this will increase the life of the ESP and reduce the cost of extracting petroleum products.

The sushiness of the proposed utility model is presented in the figures. In FIG. 1 is a General view of the device in section. Figure 2 presents the possible options for mounting the string and the sensor unit. Figure 3, a shows a cross-section of the sensor unit and Fig. 3b, a functional diagram of a measurement and data transmission unit. In the figures:

1- building;

2-string;

6- unit for measuring and transmitting data;

7- cable;

8- hydraulic compensator;

9- tubing;

10 - ground-based data recording and processing equipment;

11- base of the upper mount; 12-sleeve;

13 collet;

14- pressure screw;

15th spring;

16- adjusting nut; 17.18 - locknut;

19- housing of the sensor unit;

20 - sensor magnetic circuit;

21- upper sensor winding;

22- lower winding of the sensor;

23 - ferromagnetic disk;

24- disk hub;

25- base of the lower attachment point;

26- sleeve;

27- pressure screw;

28- adjusting nut;

D1, D2, DZ, D4 - displacement sensors; BV1, BV2 - subtraction block; U1, U2 - multiplication block;

C - szpmator;

BVK - square root calculation block; BKPD - block coding and data transmission; x1, x2, x3, x4 - signals from the outputs of the sensors D1, D2, DZ, and D4

respectively; Dh1z, Ah24 - the difference of the signals from the outputs

Opposite sensors Ah is the signal corresponding to the deviation of the string 2 when the body 1 is bent.

The device consists of a sealed casing 1, in which a string 2 is located in a stretched form along the axis of the casing. The external geometric dimensions of the casing 1 are chosen exactly equal to the external dimensions of the ESP, which they intend to operate in this well. For the housing 1 of the proposed device, it is advisable to use the housings and fasteners of the pump sections, submersible motor, separator and other structural elements of a real ESP. Case 1 is attached to the tubing and lowered into the well in the same way as a real ESP is attached during its operation. The ends of the string 2 are sealed in the upper 4 and lower 3 fasteners. In the middle part, the string 2 is covered by a block of sensors 5. The outputs of the sensors of block 5 are connected to the side of the measurement and data transmission 6, the output of which is connected by cable 7 to ground-based data recording and processing equipment 10. The housing of device 1 is attached to the tubing 9. The cavity of housing 1 is filled with oil and a hydraulic compensator 8 of any known type is attached to it, for example MK-51.

The upper assembly 4 comprises a base 11, a sleeve 12 into which a collet 13 is inserted and a compression screw 14 is screwed. The sleeve 12 can be axially moved and spring loaded with a spring 15. This ensures a constant tension of the string 2 when it is extended, for example, when temperature changes or stretching. The force of the spring 15 is regulated using the nut 16. The lock nuts 17 and 18 protect the corresponding parts 14 and 16 from unscrewing. The lower attachment point of the string 3 contains a base 25, a sleeve 26, a collet 13, a pressure screw 27 and a lock nut 28. The bases 11 and 25 are mounted in the housing 1 by any known method, for example, welding, screws (not shown in the figures) or pinching when screwing individual body elements 1. The string 2 is inserted into the Central holes of the collets 13 of both attachment points and clamped by tightening the pressure screws 14 and 27, respectively. Other known methods of embedding the string can be applied, ensuring that its tense state is maintained in the operation of the device.

The sensor unit 5 consists of a base 19 and four inductive slotted displacement sensors, each of which contains a magnetic circuit 20 and two windings 21 and 22. The base 19 is mounted in the middle of the housing 1 similarly to the fasteners of parts 11 and 25. The magnetic circuit 20 is open and has C - shaped with a slot. One of these windings, for example 21, is exciting and an alternating current voltage is supplied to it from a separate generator, not shown in the figures. The other winding, in this case 22, is a measurement winding. On the string 2, with the help of the sleeve 24, a ferromagnetic disk 23 is mounted so that it

The PLANE entered the slots of the magnetic wires of 20 of all four sensors. Depending on the selected frequency of the alternating current in the exciting winding, the magnetic circuit 20 is made of ferrite, permalloy or from plates of electrical steel. The principle of the sensor is that the alternating magnetic field generated in the magnetic circuit 20 by the exciting winding 21 induces an alternating voltage in the measuring winding 22. The magnitude of the indicated voltage depends on the magnitude of the magnetic flux passing through the magnetic circuit and the air gap in the slot of the magnetic circuit. If there is a ferromagnetic object in the slot, in this case a disk 23, the magnetic permeability of which is higher than the magnetic permeability of air, the magnetic flux through the measuring winding 22 increases, thereby increasing the voltage at the terminals of the specified winding. Moreover, the more the disk 23 moves into the slot of the magnetic circuit 20, the higher the signal amplitude at the output of the corresponding sensor and vice versa. Other well-known mixing sensors can be used in the device; for example, transformer, capacitive, optical, etc.

The outputs of the pairwise opposite sensors D1, DZ and D2, D4 are connected to the inputs of the subtraction blocks, BV1 and BV2 so that at the outputs of these subtraction blocks the differences of the signal values of these sensors are formed:

This function, in particular, can be realized by switching on the measuring windings 22 of the opposite sensors in opposite directions so that the signal of one sensor is subtracted from the signal of the other sensor already in the indicated windings.

The outputs of the blocks BV1 and BV2 are connected to the inputs of the multiplication blocks U1 and U2, which here implement the function of squaring the signals Ax and Ax24. The outputs of blocks U1 and U2 are connected to the signal adder C, the output of which is connected to the input of the square root calculation block BVK, at the output of which the signal Ax is generated. According to the above algorithm and due to the fact that the sensors are located crosswise, the magnitude of the specified signal is equal to:

which, in accordance with the Pythagorean theorem, allows us to obtain the signal Ax exactly equal to the deviation of the disk 23 in the slots of the magnetic circuits 20 of the sensors D1 and D4, regardless of which direction the specified disk deviates. The technical implementation of the considered algorithm can be carried out on a modern

Axi3 x1 - x3;

Ah24 x2-x4.

(Ah, h) + (Ah, 4),

electronic element base in both analog and digital versions. So, the construction of U1, U2 and BVK units is easy to implement on the K525PS2 chip, and the adder on any known operational amplifier.

The output of the BVK unit is connected to the input of the BKPD encoding and data transmission unit with the help of which the Lx signal is converted to a form convenient for transmission, for example, in accordance with the RS 232 interface protocol. Any known device can be used as the BKPD. The output BKPD cable 7 is connected to the input of ground-based equipment for recording and processing data 10.

The device operates as follows. The housing 1 attached to the tubing 9 is lowered into the investigated well in accordance with the established rules for tripping. As you descend, cable 7 is attached to the next tubing string pipe using clamps. When the minimum permissible suspension depth of the EEC is reached, which is determined, for example, from the conditions

where rpriem. - design pressure at the intake of a running pump; RG - the content of free gas at the reception of a working pump, include ground equipment 10.

At those intervals of the wellbore where the housing 1 is not subjected to bending, the string 2 and the associated disk 23 are located in the center section of the housing 1 and in the center of the sensor unit 5. In this case, the disk 23 equally enters the gaps of the magnetic circuits 20 of all four sensors D1 - D4. The signals at the outputs of the measuring windings 22 of these sensors are equal to each other, and the pairwise differences of these signals are equal to zero. Accordingly, the output signal of the IAC unit is equal to zero. This information is encoded and transmitted using BKPD through cable 7 to ground equipment 10.

With the passage of curved sections of the well, the device body 1 bends, and the string 2 and the associated disk 23 are displaced from the center of the sensor unit 5, as shown in Fig. 3, and with a dashed line. In this case, the disk enters deeper into the slots of the sensors D2 and DZ and at the same time leaves the slots of the sensors D1 and D4. As a result of this, the signals at the outputs of the sensors D2 and DZ will increase, and at the outputs of the sensors D1 and D4 will decrease. Consequently, the difference between the signals of the pairwise opposite sensors Lx1z and Lx24 and the output signals of the blocks BV1, BV2, U1, U2, s and BVK will increase. The greater the bending of the housing 1, the greater the deviation of the string 2 and the disk 23 and

Reception. 2.0 MPa;

Rg 0.2,

the greater the increase in the signal at the output of the BVK unit. The magnitude of this signal is also transmitted through BKPD and cable 7 to ground equipment 10, with the help of which the measured value of the bending of the body is recorded and displayed on the indicating means, thereby assessing the degree of bending of the corse 1 at a given point in the wellbore, and therefore the degree of bending of the real ESP at a given point.

It is advisable to lower the device into the well and measure the degree of bending of the body 1 along the entire wellbore, for example, to depths at which the ambient pressure becomes equal to the maximum permissible value determined by the regulation on the operating conditions of a real ESP.

The points highlighted in this way, at which the measured bend is minimal, are the optimal suspension points for a real ESP. Lighting the ESP at these points allows the pumps to be operated with minimal bending loads. This, in turn, allows you to reduce, for example, the level of vibration during pump operation and eliminate the negative consequences associated with this, such as the destruction of the fasteners of sections, UETS flaps and flights, to reduce the number of damage to shafts and other structural elements and to reduce their wear. This will increase the safety level and increase the operational life of the ESP, as well as reduce the cost of extracting petroleum products.

1.Nat. No. 2166084 RU, E 21 V 47/022 A device for determining the angle of curvature of wells.

2. Installations of submersible centrifugal pumps for oil production. International translator. Ed. V.Yu. Aleksperov et al., M., 1999, 611s.

3. Patent No. 2018648 RU, E 21 V 47/022 Device for measuring the angle of inclination of the well.

4. Patent .№2166085 RU, Е 21 В 47/022 Device for determining the curvature of wells.

Sources of information:

Claims (7)

1. A device for determining the optimal suspension location of the installation of an electric centrifugal pump in deviated wells, comprising a housing, a sensing element, a cable and ground-based data recording and processing equipment, characterized in that a string, a metal disk, upper and lower string attachment points are additionally inserted into it , a block of sensors and a block for measuring and transmitting data, moreover, the specified string is used as a sensitive element, fortified along the axis of the housing with the help of the upper and lower nodes replicating the string, and on which a metal disk is fixed so that its plane is perpendicular to the axis of the string, and a sensor block consisting of a base and four displacement sensors that are located crosswise around the perimeter of the specified base, and the sensor block is fixed in the cavity of the body in this way so that the metal disk interacts with the sensors when the string is deflected, and the outputs of the sensors are connected to the cable through the measurement and data transmission unit. 2. The device according to claim 1, characterized in that the disk is made of ferromagnetic material, and the sensors are inductive displacement sensors. 3. The device according to claim 2, characterized in that the inductive displacement sensors are slotted, having a slot, and the sensor unit and the ferromagnetic disk are installed so that the plane of the disk enters the slots of these sensors. 4. The device according to any one of claims 1 to 3, characterized in that for launching it into the well, it is attached to tubing (tubing), and the overall dimensions of the housing and the elements of the housing to the tubing are chosen equal to the overall dimensions and similar to the mounting of the electric installation submersible pump, which is supposed to operate in this well. 5. The device according to any one of claims 1 to 4, characterized in that the cavity of the body is sealed. 6. The device according to any one of claims 1 to 5, characterized in that the cavity of the housing is filled with oil, and a hydraulic compensator is attached to the housing, the cavity of which communicates with the cavity of the housing. 7. The device according to claim 1, characterized in that the measurement and transmission unit contains the first and second subtraction units, the first and second multipliers, the adder, the square root calculation unit, and the encoding and data transmission unit, the outputs of pairwise opposite sensors being connected to the inputs the first and second subtraction blocks, and the outputs of the subtraction blocks are connected respectively to the inputs of the first and second multiplier, the outputs of these multipliers are connected to the inputs of the adder, and the output of the adder is connected to the input of the qua calculation block a dubious root, the output of which is connected to the cable through the coding and data transmission unit.