RU2492306C2 - Unit to control power load onto working elements - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: unit to control power load onto working elements of a screw downhole motor comprises a half-coupling with radial and axial through channels, a spring-loaded container installed in the axial through channel of the half-coupling with a hydraulic monitor attachment, a burnisher of alternating cross section, installed as capable of axial displacement, a spring and seals. It also comprises a hollow pressing nut installed in the axial through channel of the half-coupling for interaction with the spring-loaded container and with an inner ledge made in the axial through channel of the half-coupling or the burnisher. The burnisher is made in the form of a replaceable tip installed onto the stem.

EFFECT: makes it possible to increase efficiency, reliability and durability.

3 cl, 1 dwg

Description

The node for regulating the power load on the working bodies of a downhole motor is a drilling technique and can be used when drilling oil and gas wells as part of a downhole motor.

A known unit for regulating the power load on the working bodies of a downhole motor, containing a container with a hydraulic nozzle installed in the flow channel of the hollow rotor, seals the stationary joints (see, for example, the book "Downhole Motors" by DF Baldenko and others. Moscow, Nedra , 1999. Reference manual, p. 46. Fig. 2.6; Fig. 2.7).

In the known node for regulating the power load on the working bodies, a container with a hydraulic nozzle is installed in the hollow rotor and the flow channel is constantly open for the flow of flushing liquid in both forward and reverse directions.

A disadvantage of the known node for regulating the power load on the working bodies is that the downhole motor is not protected from sludge through flushing holes in the bit during tripping.

When the downhole screw motor is lowered into the well, the flushing fluid containing sludge (pieces of cuttings) penetrates unhindered through the hollow rotor, through the working bodies, through the flow channel of the control unit in the engine. The sludge settles and remains in the working bodies, disrupting the contact of the rotor and stator, intensively wears them out or is cemented in them, rendering the engine unusable.

Another disadvantage of the known regulation unit is that during operation of the downhole motor, a portion of the volume of flushing fluid, unproductive flowing through the flow channel of the regulation unit, bypasses the working bodies and does not perform work on the rotor rotation (the energy capability of the downhole motor is actually unreasonably reduced).

The regulation of the power load on the working bodies is carried out by periodically changing the performance of the mud pumps supplying flushing fluid to the engine. And this requires additional time, labor and money and is often not done. And with a sharp increase in the bottomhole load associated with the transition of the bit from one formation to another, more or less viscous, the pressure drop on the working bodies and in the control unit increases sharply, the flow cross section of the flow channel is significantly reduced, the amount of flushing fluid flowing through the control unit is shrinking. In this regard, the volume of flushing fluid flowing through the working bodies under excess pressure increases and significantly increases the power load on the working bodies. As a result, the intensity of wear of the working bodies increases significantly. The rotor and stator are rapidly worn out, wear out, prematurely become unusable due to accidental wear. These and other disadvantages of the known regulation node limit the possibility of its practical use in drilling oil and gas wells.

A known unit for regulating the power load on the working bodies in a downhole screw motor, comprising a container with replaceable hydraulic monitor nozzles with various shapes and different sizes of the cross-section of the passage channel (see, for example, AS No. 1430491 A1, ЕВВ 4/02, from 15.10.88 Bulletin No. 38).

The disadvantages of the known regulation node are similar to those inherent in the previous known regulation node.

In addition, the significant disadvantages of the known unit for regulating the power load on the working bodies include the fact that the known control unit uses hydromonitor nozzles with a complex shape of the flow channel, the determination of the degree of influence of which on the work of the working bodies of the downhole motor is problematic.

Also, the disadvantages of the known regulation unit include the useless uninterrupted discharge of a portion of the washing liquid through the hydraulic nozzle at each operating mode of the downhole screw motor. From this, engine performance decreases, its technical and technological capabilities decrease.

These and other disadvantages significantly reduce the economic efficiency of the use of the known node for regulating the power load on the working bodies of the downhole motor and do not allow to achieve a positive technical result.

A known unit for regulating the power load on the working bodies of a downhole screw motor, comprising a sleeve with an axial flow channel installed in a spring-loaded rotor with the possibility of axial movement, containing a stepwise variable-section socket, a mandrel for interacting with the socket, is fixed to the housing (see, for example, U.S. Patent No. 5,174,392 of December 29, 1992, E21B 4/02).

When the engine is running through the unit for regulating the power load on the working bodies, part of the volume of flushing fluid supplied to the engine flows and is uselessly lost without performing work. As the bottomhole load increases and the pressure drop across the working bodies increases, the sleeve slides on the mandrel with its nest and partially or completely blocks the flow channel of the control unit.

In this regard, the entire volume of washing liquid under increasing pressure is passed through the working bodies, increasing the load on the working bodies.

A disadvantage of the known unit for regulating the power load on the working bodies is that due to a sharp increase in the bottomhole load, the pressure in the working bodies and in the control unit increases until the resistance to rotation is overcome. This can continue until the engine stops completely. At the same time, the flushing fluid under extreme pressure deforms the rubber teeth of the stator and flows unhindered through the working elements, unproductive wear and prematurely destroying them.

Another disadvantage of the known regulation node is the complexity of its design, which requires certain additional knowledge, an enhanced culture of production and service.

These and other disadvantages do not allow the efficient use of the known node for regulating the power load on the working bodies in screw downhole motors and are an obstacle to their widespread use.

Closest to the invention in terms of technical nature and technical result achieved is a unit for regulating the power load on the working bodies, comprising a coupling with radial and axial flow channels, a spring-loaded container with a hydraulic nozzle installed in the axial flow channel of the coupling half, mounted with the possibility of axial movement of mandrels of variable cross section , spring, seals of movable and fixed joints (see, for example, patent No. 2205933, November 15, 2001, publ. June 10, 2003 Bull. No. 16, M.7. Е21В 4/02).

This invention is taken as a prototype, because it eliminated some significant drawbacks inherent in the known nodes for regulating the power load on the working bodies of a downhole screw motor: in operating mode, the entire volume of flushing fluid coming to the engine from the mud pumps is supplied to the working bodies to perform work; in extreme and transcendental modes, most of the flushing fluid supplied to the engine enters the unit for regulating the power load on the working bodies and unloads the working bodies from excessive loads.

A disadvantage of the known node for regulating the power load on the working bodies is that it does not have the ability to pre-set the value of the optimal power load on the working bodies, advance regulation of the compression force of the spring depending on the technical and energy characteristics of the downhole screw motor.

This does not allow to fully utilize the energy capabilities of each engine and provide sufficient performance, reliability and durability of a downhole screw motor in specific geological conditions.

Another disadvantage of the known node for regulating the power load on the working bodies is that it is equipped with a set of quick-change hydraulic nozzles, each with a different cross-sectional area of the flow channel. In the conditions of drilling and repair bases, this presents certain technical and organizational difficulties in the preservation, assembly and skillful use of hydraulic nozzles, appropriate sizes and is often ignored by technical services. Thus, the effectiveness of regulating the power load on the working bodies is reduced.

Another disadvantage of the known unit for regulating the power load on the working bodies is that it does not exclude the possibility of mashing, cementing and jamming of the mandrel in the hydraulic nozzle due to small radial clearances between the mandrel and the hydraulic nozzle, in which the sludge contained in the washing liquid, gaps settles, cemented and connects motionless mandrel and hydraulic nozzle, obstructing the flow of flushing fluid.

These and other disadvantages of the known node for regulating the power load on the working bodies do not allow to provide the necessary reliability and durability and reduce the possibility of its widespread use in downhole screw motors when drilling oil and gas wells.

The objectives of the invention are to eliminate the existing disadvantages of the known site of the regulation of the power load on the working bodies and the creation of the possibility of establishing, changing within wide limits and regulation of the power load on the working bodies on the workers, at ultimate and beyond bottomhole loads, preventing the possibility of intense abrasion, increased wear and tear and accidental destruction of the working bodies, eliminating the possibility of sludge entering the working bodies through flushing holes in the chisel during spu hoisting operations and ultimately increasing the reliability and durability of the unit for regulating the power load on the working bodies and the downhole screw motor as a whole.

The tasks are solved due to the fact that the known node for regulating the power load on the working bodies, containing a coupling with radial and axial flow channels, a spring-loaded container with a hydraulic nozzle installed in the axial flow channel of the coupling half, installed with the possibility of axial movement of mandrels of variable cross section, spring, the sealing of movable and fixed joints, according to the invention contains a hollow pressure nut installed in the axial flow channel of the coupling half for interaction actions with a spring-loaded container and with an internal protrusion or mandrel made in the axial flow channel of the coupling half, and the mandrel is made in the form of a replaceable tip mounted on the rod;

- a persistent end face is made on the mandrel for interaction with the end face of the hydraulic nozzle;

- the spring is made in the form of a single integral block vulcanized to each other Belleville springs.

In the proposed site for regulating the power load on the working bodies, it is possible to block the flow channel until the power load on the working bodies of the downhole screw motor reaches a certain necessary reliability and sufficient durability set in advance by the permissible conditions. The power load on the working bodies is the torque of the force developed by the working bodies to overcome the torque of rotation of the bit, i.e. to overcome the bottomhole load.

At the same time, the entire volume of flushing fluid coming from the mud pumps to the engine is sent to the working bodies to complete the work. This ensures maximum efficiency in using the energy capabilities of a downhole screw motor.

As a result of the fact that the proposed unit for regulating the power load on the working bodies of the downhole motor contains a coupling with radial and axial flow channels, a spring-loaded container with a hydraulic nozzle installed in the axial flow channel of the coupling half, mounted with the possibility of axial movement of mandrels of variable cross section, spring, seals movable and fixed joints, in addition, contains a hollow pressure nut installed in the axial flow channel of the coupling half for interactions action with a spring-loaded container and with an internal protrusion or mandrel made in the axial flow channel of the coupling half, the mandrel being made in the form of a replaceable tip mounted on the rod, the possibility of realizing the purpose is achieved, i.e. provides periodic and operational regulation of the power load on the working bodies, the effective use of the technical and energy capabilities of the downhole screw motor and the prevention of intensive abrasion, increased wear and accidental destruction of the working bodies at ultimate and beyond bottomhole loads.

As a result of the fact that in the proposed site for regulating the power load on the working bodies on the mandrel, a thrust end is made for interacting with the end face of the hydraulic nozzle, the accuracy and accuracy of operation and regulation of the power load on the working bodies with a slight axial displacement of the hydraulic nozzle are improved, the possibility of seizing is eliminated, jamming and cementing of the mandrel and hydraulic nozzle, the unit for regulating the power load on the working bodies is stored for a longer period of time The ability condition.

As a result of the fact that in the proposed unit for regulating the power load on the working bodies, the spring is made in the form of a single integral block of plate springs vulcanized to each other, the regulation unit is maintained for a longer period by preventing ingress and accumulation of sludge in the plate spring unit and elimination of their possible cracking at high deformations due to a significant increase in the elastic modulus of rubber with significant joint plates chastany springs deformations of rubber.

Thus, the implementation of the distinguishing features in conjunction with the known in the proposed site of the regulation of the power load on the working bodies creates the opportunity to eliminate the shortcomings inherent in the known site of the regulation of the power load on the working bodies and to provide the ability to establish, change within wide limits and control the power load on the working bodies on workers, at ultimate and beyond bottomhole loads, to prevent intensive abrasion, increased wear and accidental destruction of ochih organs, excluding the possibility of sludge entering the working bodies through circulating openings in the bit during tripping operations and, ultimately, increasing the reliability and durability of the power unit for controlling a load on the working bodies and the screw downhole motor as a whole.

To clarify the essence of the invention, a drawing is presented, which shows the node for regulating the power load on the working bodies. Lengthwise cut.

Thin dash-dotted lines show the working bodies of a downhole screw motor at the installation site of the power load control unit on the working bodies. Lengthwise cut.

The node for regulating the power load on the working bodies can be installed in the turbine drill turbine shaft.

The node for regulating the power load on the working bodies of the downhole motor contains a coupling 1 with radial flow channels 2 and an axial flow channel 3, mounted in the axial flow channel 3 of the coupling 1, a spring-loaded container 4 with a hydraulic nozzle 5, mounted with the possibility of axial movement of the mandrels 6 of variable cross section , spring 7, seals of movable joints 8 and seals of fixed joints 9. The node for regulating the power load on the working bodies also contains a hollow pressure nut 10, installed in the axial flow channel 3 of the coupling half 1 for interaction with the spring-loaded container 4 and with the inner protrusion 11 or the mandrel 6 made in the axial flow channel 3 of the coupling 11, the mandrel 6 being made in the form of a replaceable tip 13 mounted on the rod 12. On the mandrel 6, a thrust end 14 is made for interaction with the end face 15 of the hydraulic nozzle 5.

In the node for regulating the power load on the working bodies, the spring 7 is made in the form of a single integral block of disk springs vulcanized to each other. The mandrel 6 is fixed in the rod 12 and has the ability to thread 16 together with the container 4 or independently move in the axial direction relative to the coupling half 1.

The control unit of the power load on the working bodies is installed in the rotor 17 of the working bodies (shown in dashed lines) and is fixed on the thread 18 of the coupling half 1 tightly.

The working bodies include a rotor 17 and a stator 19 and together with the power load control unit on the working bodies form a high pressure cavity 20 and a low pressure cavity 21 with sealing the cavity with seals 9 of fixed joints made in the form of rubber rings.

Hydromonitor nozzle 5 is made of cermet, cermet or metal with a wear-resistant coating.

Dorn 6 variable section is made of metal coated with carbide composite materials.

In the proposed node for regulating the power load on the working bodies of the downhole motor, other versions of parts and assemblies are possible.

Works node regulation of the power load on the working bodies as follows.

When assembling the unit for regulating the power load on the working bodies, the container 4 is moved by rotating the hollow pressure nut 10 until its end contacts the inner protrusion 11 of the coupling half 1. Then, further rotating the hollow pressure nut 10 and compressing the spring 7 by a certain amount, press the container 4 to the internal protrusion 11 coupling halves 1 with a force ensuring the maintenance of a possible optimum pressure drop across the working bodies, corresponding to the operation of a downhole screw motor in economically advantageous modes ranging from mode m maximum efficiency up to the “maximum power” mode without flushing the flushing fluid through the unit for regulating the power load on the working bodies. The optimal pressure drop on the working bodies is established based on the energy capabilities of the downhole screw motor. Thus, the first stage of regulating the power load on the working bodies is carried out, which ensures a more profitable use of the potential capabilities of the downhole screw motor with its increased reliability, sufficient durability and significant economic efficiency.

When the unit for regulating the power load on the working bodies is operating, the washing liquid under excess pressure is supplied to the working bodies, to the high pressure cavity 20, to the radial 2 and axial 3 flow channels. As the bottomhole load increases, the pressure drop across the working bodies, and therefore between the high-pressure cavity 20 and the low-pressure cavity 21, increases until it reaches the optimum value established during the assembly of the control unit.

A further increase in the bottomhole load leads to an increase in the pressure drop between the cavities 20 and 21, respectively, of high and low pressure, overcoming the compression force of the spring 7, the axial movement of the container 4 with the hydraulic nozzle 5 down and the formation of a gap between the thrust end 14 of the mandrel 6 and the end face 15 of the hydraulic nozzle 5 .

Flushing fluid under excess pressure flows through the formed hydraulic channel in the unit for regulating the power load on the working bodies into the axial flow channel of the hollow rotor 17, through the hydraulic nozzle 5, the spring 7 and the hollow pressure nut 10. As a result, the pressure drop across the working bodies decreases, and the power load on the working bodies, the amount of flushing fluid flowing through the working bodies is reduced.

In this regard, the working bodies are freed from ultimate and transcendental power loads, their abrasion, wear and possible destruction are reduced, and the working bodies will be in a healthy state longer. In this case, the greatest productivity of the working bodies can be achieved.

With a sharp increase in the bottomhole load, for example, when the bit moves into the reservoir of a higher or lower viscosity, or with an unexpected jamming of the bit, the pressure drop on the working bodies increases stepwise and the washing liquid under excessive pressure acts on the container 4 with the hydraulic nozzle 5, moves it down and, overcoming the resistance of the spring 7, instantly opens the flow channel between the thrust end 14 of the mandrel 6 and the end face 15 of the hydraulic nozzle 5. In this case, most of the flushing fluid entering the engine, the pressurized chamber 21 is discharged into the low pressure.

The pressure drop across the working bodies decreases sharply, and the working bodies are freed from overload: the rotor 17 and the stator 19 are no longer subjected to intensive abrasion, increased wear and accidental destruction and are kept in good condition.

Thus, the second stage of regulation of the power load on the working bodies is carried out, which ensures the prevention of the possibility of intensive abrasion, increased wear and emergency destruction of the working bodies on the workers, at ultimate and beyond bottomhole loads.

When performing drilling operations with downhole screw motors, in case of unforeseen changes in geological conditions, there is a need to increase the rigidity of the energy characteristics of the engine. For this, in the node for regulating the power load on the working bodies, it is possible to change the previously established optimal power load on the working bodies by increasing the pressing force of the thrust end 14 of the mandrel 6 to the end face 15 of the hydraulic nozzle 5 to the force corresponding to the operation of the downhole screw motor at maximum power. To do this, by rotating the rod 12 on the thread 16, the mandrel 6 moves down a certain amount. In this case, the spring 7 is compressed and the pressing force of the end face 14 of the mandrel 6 to the end face 15 of the hydraulic nozzle 5 increases.

Thus, the third stage of regulation of the power load on the working bodies is carried out, which provides the opportunity to increase the load capacity of the working bodies from optimal to maximum operating mode of the downhole screw motor.

If it is necessary to mitigate the energy characteristics of the downhole screw motor on the drilling rig, it is enough to turn the rod 12 on the thread 16 and raise it by a certain amount to form a gap (and a flow channel) between the thrust end 14 of the mandrel 6 and the end face 15 of the hydraulic nozzle 5. Moreover, some of the volume flushing fluid will flow freely through the control unit, bypassing the working bodies, and soften the energy performance of the engine during each operation of the downhole motor la.

Thus, the fourth stage of regulation of the power load on the working bodies is carried out, which ensures the work of the working bodies in gentle modes with a reduced power load on the working bodies.

As a result of the fact that the proposed node for regulating the power load on the working bodies contains a hollow pressure nut 10 installed in the axial flow channel 3 of the coupling 1 for interaction with the spring-loaded container 4 (with a hydraulic nozzle 5) and with the coupling coupling 3 made in the axial flow channel 3 the inner protrusion 11 or turf 6, and the mandrel 6 is made in the form of a replaceable tip 13 mounted on the rod 12, the ability to set the optimal value of the compression force of the spring 7 corresponding to cally justified power load on the working bodies of the screw downhole motor providing flushing fluid pressure discharge cavity 20 from the high pressure in the low pressure cavity 21 (at achievement of this value) and reducing the power load on the working bodies at the downhole load increases further. At the same time, it is possible to quickly replace a worn or accidentally washed replaceable tip 13 directly on the drill. This ensures the achievement of a technical result: the implementation of the assignment, which consists in regulating the power load on the working bodies when achieving optimal power loads on the working bodies, in reducing the power loads with a further increase in bottomhole load and in preventing intense abrasion, premature wear and accidental destruction of parts and screw bottomhole engine as a whole. Due to the fact that in the proposed site for regulating the power load on the working bodies on the mandrel 6, a thrust end 14 is made for interaction with the end face 15 of the hydraulic nozzle 5, the possibility is created and realized to block the flow channel with end surfaces and with a slight excess of the optimum power load established during assembly on the working bodies, the control unit significantly increases the area of the flow section of the flow channel formed between the thrust end 14 of the mandrel 6 and the end face 15 of the nozzle 5 and provides the discharge of a certain volume of washing liquid from the high-pressure cavity 20 into the low-pressure cavity 21, at which the pressure drop across the working bodies decreases, the power load on the working bodies decreases, the possible wear of the rotor 17 and the stator 19 is reduced, and their reliability and durability are increased.

Due to the fact that in the proposed node for regulating the power load on the working bodies, the spring 7 is made in the form of a single integral block of disk springs vulcanized to each other, protection of the disk springs from the influence of flushing liquid on them is prevented, sludge is prevented from entering the disk springs and excludes the possibility of cracking of Belleville springs at ultimate and beyond bottomhole loads.

In the unit for regulating the power load on the working bodies, the seals 8 of the movable joints ensure the tightness of the container 4 in the coupling half 1 and reduce the leakage of flushing fluid from the high pressure cavity 20 into the low pressure cavity 21, the seals 9 of the fixed joints seal the parts and the assembly as a whole in the rotor 17.

Thread 18 is used to connect and fasten the coupling half 1 in the hollow rotor 17.

When the bottomhole load and pressure drop on the working bodies change during the drilling process, the power load on the working bodies is regulated automatically.

Automatic regulation of the power load on the working bodies is as follows.

The power load on the working bodies largely depends on the bottomhole load and is controlled by the pressure drop across the working bodies.

Under the action of increasing, above the established optimum, pressure drop on the working bodies, associated with an increase in bottomhole load, the container 4 with the hydraulic nozzle 5 shifts down and compresses the spring 7. At the same time, a gap is formed between the thrust end 14 of the mandrel 6 and the end face 15 of the hydraulic nozzle 5, which as the pressure drop across the working bodies increases, increasing the cross-sectional area of the flow channel. As a result, the flow rate of the flushing fluid through the control unit of the power load on the working bodies increases, and through the working bodies it decreases, this reduces the rotational speed of the bit and the amount of drill cuttings decreases, the flushing and cleaning of the face from drill cuttings improves and the bottom load decreases. And as a result, the pressure drop decreases and the power load on the working bodies decreases.

Due to the decrease in the pressure drop across the working bodies caused by the decrease in the bottomhole load, the container 4 with the hydromonitor nozzle 5 rises up under the action of the spring 7, and the cross-sectional area of the flow channel decreases or the flow channel is completely closed.

As a result, the flow rate of flushing fluid through the control unit of the power load on the working bodies decreases, causing an increase in the flow rate of flushing fluid through the working bodies.

In this case, the rotational speed of the hollow rotor 17 and the bit increases, the amount of drill cuttings increases, and the operating mode of the downhole screw motor set by the control unit of the power load on the working bodies is restored.

Thus, the implementation of the distinguishing features of the proposed site of the regulation of the power load on the working bodies of the downhole motor in combination with the known ones, creates the opportunity to eliminate the shortcomings inherent in the known site of the regulation of the power load on the working bodies, and to achieve a positive technical result - the implementation of the purpose:

- the opportunity has been created for the establishment, change over a wide range and periodic and operational regulation of the power load on the working bodies on the workers, on the ultimate and beyond the bottomhole loads;

- preventing the possibility of intensive abrasion, increased wear and accidental destruction of the working bodies and maintaining for a longer period the unit for regulating the power load on the working bodies and the whole downhole motor in working condition;

- improving the performance of a downhole screw motor by reducing wasteful losses of flushing fluid and more efficient use of the energy capabilities of the engine while increasing reliability and durability;

- elimination of the possibility of sludge entering the working bodies through flushing holes in the bit during tripping and ultimately increasing the reliability and durability of the power load control unit on the working bodies and the downhole screw motor as a whole.

All this makes it possible to reduce losses and reduce unproductive flow rate of flushing fluid, increase productivity, reliability and durability, reduce production costs for drilling oil and gas wells, increase the economic efficiency of using the unit for regulating the power load on the working bodies of a downhole screw motor, i.e. allows you to solve the tasks of the invention.

Claims (3)

1. The site of regulation of the power load on the working bodies of the downhole motor, containing a coupling with radial and axial flow channels, a spring-loaded container with a hydraulic nozzle installed in the axial flow channel of the coupling half, mounted with the possibility of axial movement of mandrels of variable cross section, spring, seals movable and stationary connections, characterized in that it contains a hollow pressure nut installed in the axial flow channel of the coupling half for interaction with a spring-loaded m container and formed in the axial flow channel coupling half inner lug or mandrel, the mandrel is designed as a replaceable tip mounted on the rod. 2. The node according to claim 1, characterized in that on the mandrel is made a persistent end face for interaction with the end face of the hydraulic nozzle. 3. The node according to claims 1 and 2, characterized in that the spring is made in the form of a single integral block vulcanized to each other plate springs.

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