RU2652724C1 - Stator of screw gyratory hydraulic machine - Google Patents

Abstract

FIELD: drilling soil or rock.

SUBSTANCE: invention relates to hydraulic drives for rotary drilling located in wells. Stator comprises a tubular body with an inner surface made in the form of a helicoid with internal helical teeth, an internal thread is formed at each edge of the tubular body, and also contains an elastomeric plate attached to the tubular body adjacent to the inner surface of the tubular body, the elastomer cover is made with internal helical teeth and coincides in shape with the internal helical teeth in the tubular body, and the thickness of the lining is maximum on the teeth, radially directed inwards. In the tubular body, the maximum thickness of the elastomer liner along the valleys of its inner helical surface located at the maximum radial distance is half the height of its internal helical teeth, and the minimum wall thickness of the tubular body along the radially outwardly directed depressions of its internal helical surface is equal to the height of the inner helical teeth in the elastomer plate. Elastomer cover comprises, in the upstream portion of the tubular body, upstream of the edge of the internal helical teeth facing the flow, input damper of elastomer with its own internal helical teeth, adjacent to the internal helical teeth of the elastomer, the surface of the tubular body, which is adjacent to the inner surface of the upstream portion, is capable of being fastened to an elastomeric plate, the lateral surfaces of the inner helical teeth of the tubular body facing against the flow, and the inner surface of the upstream portion of the tubular body. Downstream of the edge of the internal helical teeth of the tubular body in the downstream portion of the tubular body, the elastomer cover comprises an elastomer output damper with its own internal helical teeth, adjacent to the internal helical teeth of the elastomer, located in the tubular body, that adjoined to the inner surface of the downstream portion of the tubular body with the possibility of bonding to the elastomeric plate, the lateral surfaces of the inner helical teeth of the tubular body being directed downstream and the inner surface of the downstream portion of the tubular body. Minimum thickness of the input and output dampers from the elastomer along the valleys of their internal helical teeth located at the maximum radial distance is equal to the thickness of the elastomer plate on its teeth radially inward.

EFFECT: reliability and resource are increasing, accuracy of penetration of inclined and horizontal wells, rate of set of curvature parameters of wells, as well as cross-country ability, that is resistances and stresses in the bottom-hole assembly are reduced.

1 cl, 8 dwg

Description

The invention relates to hydraulic actuators for rotary drilling, placed in the well, in particular to screw gerotor hydraulic motors for drilling oil and gas wells.

Known screw hydraulic mechanism used as a pump or engine, containing a stator housing and a rotor, the rotor has an external helical surface, and the stator housing is made in the form of a monolithic rigid tubular element having a cylindrical outer surface and an inner surface, and also having helical teeth wherein said mechanism comprises a flexible layer made of an elastomer having a uniform thickness on the inner surface of the housing (US 2005/0079083 A1, 04/14/2005).

In the known hydraulic mechanism, a flexible layer made of an elastomer having a uniform thickness on the inner surface of the housing undergoes deformation and bending during planetary-rotor rotation of the rotor inside the stator, which leads to the formation of zones on the protrusions and depressions of the teeth that differ in contact pressure , shear strength, hardness (elasticity) and thermal conductivity.

The temperature in the elastomeric casing can increase, for example, to 60 ° C, and the increase in interference in the working pair can be, for example, up to 0.05 mm per diameter for every 10 ° C increase in temperature.

A disadvantage of the known design is the incomplete use of the possibility of increasing the reliability and service life of the helical hydraulic mechanism when it is used in a downhole screw motor, as well as increasing the maximum power, the torque on the output shaft in the maximum power mode and the fatigue endurance (resource) of the elastomer plate - not less than 100 thousand cycles.

The disadvantages of the known design are explained by the incomplete possibility of optimizing the thickness of the plate from the elastomer along the protrusions and depressions of the helical teeth, which leads to a deterioration in the removal of internal heat from the plate from the elastomer to the flow of the drilling fluid inside the body, as well as through the walls of the body to the flow of the drilling fluid of the annulus, the formation of the centers of the profile of the elastomeric lining of the zones of destruction of the material from the effects of a temperature gradient and an increase in interference in the working pair.

As a result, the center of the profile becomes less flexible (brittle and brittle), the mechanical properties of the elastomer, for example rubber, in these areas are significantly deteriorated, while the pressure acting in the chambers between the rotor and the stator can exceed the shear strength of the elastomer, and the tops of the teeth in the lining deform and come off the body.

A known stator of a screw gerotor hydraulic pump or motor, comprising a housing with an inner surface made with internal helical teeth, a male and female elastomer plates fixed to the housing, the male plate being made with internal helical teeth, designed to accommodate a rotor having an outer surface with with helical teeth, the female lining is fastened to the male lining and to the inner surface of the housing, and the number of rotor teeth per unit it bigger number of housing teeth (US 6,881,045 A, 23.12.2004).

The known hydraulic mechanism contains a flexible layer made of an elastomer having a uniform, substantially the same thickness on the inner surface of the housing, which leads to the formation of zones on the protrusions and depressions of the teeth of the teeth that differ from each other in terms of contact pressure, shear strength, hardness (elasticity) and thermal conductivity, which are subjected to deformation and bending during planetary-rotor rotation of the rotor inside the stator.

The disadvantages of the known design are explained by the incomplete possibility of optimizing the thickness of the plate from the elastomer along the protrusions and depressions of the helical teeth, which leads to a deterioration in the removal of internal heat from the plate from the elastomer to the flow of the drilling fluid inside the body, as well as through the walls of the body to the flow of the drilling fluid of the annulus, the formation of the centers of the profile of the elastomeric lining of the zones of destruction of the material from the effects of a temperature gradient and an increase in interference in the working pair.

As a result, the center of the profile becomes less flexible (brittle and brittle), the mechanical properties of rubber or elastomer in these areas significantly deteriorate, while the pressure acting in the chambers between the rotor and the stator can exceed the shear strength of the elastomer, and the tooth tips in the lining are deformed and come off the case.

A disadvantage of the known design is also the low strength of the stator housing, as well as the loss of its stability mainly under axial load on the bit and impact from jars in the composition of a curved drill pipe string in directional wells, for example, when passing through the radius sections of the wellbore during horizontal drilling, which is explained by the fact that it is made composite: from the body - a smooth pipe, covered and covering plates of elastomer, made in the form of a helicoid.

An elastomeric male lining of the same thickness is made of a material, for example, Ultra-Flex 114, and an additional female lining with an internal surface in the form of a helicoid, essentially with internal helical multiple teeth, is made of a harder and stronger material.

Moreover, the well-known stator when used in a screw gerotor hydraulic motor does not provide significant advantages, for example, the maximum rate of set of curvature (when drilling a directional well) due to the destruction of the body, for example, when passing through the radial sections of the wellbore during horizontal drilling using a column drill pipe hydromechanical jar, with rotation (from the rotor of the drill) curved string of drill pipes (20 ÷ 40 rpm), with shock loads and shock impulse and from the hydraulic jar, as well as due to relaxation of the tensile stress at a bent drill string, wherein the motor stator is mounted.

The disadvantages of the known stator are also explained by the cyclic loading of helical teeth made, for example, of elastomers of different shear strength, hardness and thermal conductivity, which are subjected to deformation and bending during planetary-rotor rotation of the rotor inside the stator, which leads to heat generation inside the tooth material, and the tension in working pair, peeling of the elastomeric plates from the housing, as well as to delamination between the elastomeric plates due to the deterioration of internal heat removal from the elastomeric plates and through a layer of material through the walls of the body to the drilling fluid annulus.

In this case, the temperature in the elastomeric casing can increase, for example, to 85 ° C, and the increase in interference in the working pair can be, for example, up to 0.08 mm per diameter for every 10 ° C of temperature increase, which leads to non-calculated operating modes, not provides maximum power, torque on the output shaft in maximum power mode and permissible axial load with increasing maximum pressure drop (inter-turn, on the stator teeth) in maximum power mode.

Known stator for a downhole hydraulic motor, forming an outer pipe with an inner surface made of at least two internal helical teeth (or blades), a lining fixed in the housing, for example, from an elastomer, adjacent to the inner surface of the outer pipe, while the lining made with internal helical teeth (or blades), coincides in shape with internal helical teeth (or blades) in the outer tube, and the thickness of the lining is maximum on the teeth (or blades), radially inwardly directed (at least two) (US 6604921 B1, 14.04.2005).

A disadvantage of the known design is the incomplete use of the possibility of increasing the reliability and service life of a downhole screw motor, maximum power, torque on the output shaft in the maximum power mode and fatigue endurance (resource) of the elastomeric lining - at least 100 thousand cycles.

Since the elastomer is characterized by high insulating properties, it delays the transfer of heat to a greater extent along the protrusions of the helical teeth compared to the depressions of these helical teeth.

The temperature in the elastomer lining can increase, for example, to 85 ° C, and the increase in interference in the working pair can be, for example, up to 0.08 mm per diameter for every 10 ° C temperature increase, which leads to off-design operating modes, does not provide maximum power, torque on the output shaft in maximum power mode and permissible axial load with increasing maximum pressure drop (inter-turn, on the stator teeth) in maximum power mode.

The disadvantages of the known stator for a screw gerotor hydraulic machine are explained by the incomplete use of the possibility of optimizing the thickness of the lining along the hollows of the internal helical surface and the minimum wall thickness of the outer tube with respect to the height of the teeth in the lining, as well as the formation of zones on the protrusions and hollows of the teeth that differ in contact pressure , shear strength, hardness (elasticity) and thermal conductivity, which are subjected to deformation and bending during planetary-rotor rotation of the rotor three stators, which leads to an increased temperature gradient when heat is generated inside the tooth material and violation of interference in the working pair, to a deterioration in the removal of internal heat from the elastomeric sheath to the mud flow inside the housing, and also through the walls of the outer pipe to the annular drilling mud, the flow which is directed from the bottom to the wellhead.

Due to the heat generated in the tooth centers, secondary polymerization occurs: molecular crosslinking of the elastomer (rubber), which leads to degradation of the material, as a result, the center of the lining profile becomes inflexible (brittle and brittle), the mechanical properties of the elastomer in these areas significantly deteriorate, In this case, the pressure acting in the chambers between the rotor and the stator can exceed the shear strength of the elastomer, and the vertices of the stator are deformed and detached from the stator.

Closest to the claimed design is the stator of a screw gerotor hydraulic machine, for example, a motor for rotating the rotor from the pump fluid supply or a pump for supplying fluid by rotating the rotor, comprising an outer pipe with an inner surface made in the form of a helicoid with internal helical teeth, fixed in the outer tube lining of elastomer adjacent to the inner surface of the outer pipe, while the lining is made with internal helical teeth and matches the shape of the inner by them with helical teeth in the outer pipe, and the thickness of the lining is maximum on the teeth radially directed inward, in the outer pipe, the maximum thickness of the lining of elastomer along the valleys of its internal helical surface located at the maximum radial distance is equal to half the height of its internal helical teeth, and the minimum the wall thickness of the outer pipe along the radially outward troughs of its inner helical surface is equal to the height of the internal helical teeth in the elastomer lining (RU 2373364 C2, 20.11.20 09).

The main advantages of the famous stator with a uniform thickness of the lining of elastomer (R-Wall):

- increases the load capacity of the stator, hysteresis losses in the lining are reduced, energy characteristics and braking torque of the engine section are increased, which eliminates the likelihood of engine braking when the load changes and increases the controllability of drilling;

- the amount of generated and stored heat is reduced, the interference in the stator rotor-lining connection is less dependent on the temperature and degradation ("swelling") of the elastomer, high energy characteristics are ensured in the extended interval of the well depth, temperature and oil-based drilling fluids;

- improved energy characteristics of the engine allow its efficient use with PDC (Polycrystalline Diamond Compakt) bits with polycrystalline diamonds;

- due to the smaller thickness of the elastomer, when the pieces of the lining are torn off, the flushing holes of the bit are not clogged, as a result of which the required interval of the well can be completed to the end, the mean time between failures (Journal of Drilling and Oil, 11/2014, p. 56 ÷ 59) .

The incomplete possibility of increasing reliability and resource is explained by the possibility of defects in a known design in which the stator is made with a uniform thickness of the lining of the elastomer (R-Wall): cracking, peeling, as well as tearing pieces of the lining of the elastomer (rubber) at the edges in the inlet and the downstream parts of the plate from the elastomer in the stator under intense operating conditions: if there is a necessary interference between the rotor and the tubular body lining, the contact pressure is 2.5 ÷ 3 MPa, shear rate life is 0.5 ÷ 2.5 m / s, hydrostatic pressure can reach 50 MPa, and the moment of force on the output shaft in maximum power mode can reach 30 kN⋅m, and in conditions of high turbulence of the drilling fluid, which has a density of up to 1500 kg / m ³ , contains up to 2% of sand and up to 5% of oil products, which leads to the cessation of circulation, with the main reason for the failure of the layout of the bottom of the drill string (BHA), in which the motor section with spindle and chisel is installed, - rubber in chisel. "

The development of the mentioned defects is facilitated by high working pressure drops, internal heat generation in the stator lining material, braking of the working couple during operation, high interference in the working couple.

The increase in the length of the section of the working pairs can significantly reduce the level of contact loads in the engagement of the working couple and prevent premature destruction of the lining of the elastomer at the edges of the stator.

At the same time, the energy characteristics of the engine, reliability and resource are increased. However, the increase in the length of the working pairs of the rotor-stator worsens the permeability of the layout of the bottom of the drill string when passing through the radius sections of the wellbore during horizontal drilling.

Due to the peculiarities of the operation of the gerotor mechanisms of screw hydraulic machines along the edges of the elastomer lining, additional heat is generated and stored due to the influence of the distorting moments of the rotor during its planetary-rotor rotation inside the teeth of the stator lining from the elastomer in the maximum power mode.

As a result, the center of the profile becomes less flexible (brittle and brittle), the mechanical properties of the elastomer, for example rubber, in these areas are significantly deteriorated, while the pressure acting in the chambers between the rotor and the stator can exceed the shear strength of the elastomer, and the tops of the teeth in the lining deform or detach from the body, while reducing the possibility of increasing the maximum power, the torque on the output shaft in the maximum power mode and fatigue endurance (resource) of the lining of elastomer - n e less than 100 thousand cycles.

As a result, the properties of the elastomer in the structure are not ensured, for example, fatigue endurance during alternating bending with rotation (GOST 10952-75), permanent deformation and fatigue endurance during repeated compression (GOST 20418-75), temperature limit of brittleness (GOST 7912-74), abrasion when sliding (GOST 426-77).

Another disadvantage of the known design is the incomplete possibility of increasing reliability and service life by providing equal strength and tight threaded joints of the stator tubular body with an adapter and / or adapter under conditions of intense friction and rotation in the wellbore, using hydraulic jars in the drill pipe string, with shock loads and shock pulses from jars, as well as during relaxation of tensile stresses in a curved drill pipe string, in which a stator screw gero hydromachines.

The mentioned drawback of the known construction is explained by the increased stiffness of the tubular body when used in the stator of a hydraulic downhole motor, essentially by a large value of the stress coefficient under bending (Stress ratio, the ratio of the changing voltage amplitude to the average voltage) at the junction of the threaded joints of the tubular body with the sub and / or an adapter equal to 7 ÷ 9, as well as a high probability of cracking on the threads and breakage of the threaded joints of the tubular body when using a downhole motor driven horizontal in the bottom hole assembly, the areas changing downhole curvature, preferably a maximum power mode.

Due to the increased stiffness of the tubular stator housing, the possibility of increasing the accuracy of drilling of deviated and horizontal wells, increasing the rate of a set of parameters of the curvature of the wells, as well as improving patency, i.e. reducing the resistance and stresses in the layout of the bottom of the drill string due to bending of the tubular body of the downhole motor when passing through the radius sections of the borehole having sections of small and medium radius 30 ÷ 300 m, under conditions of intense friction along the borehole.

As a result of this, the required interval of wells cannot be completely completed, for example, in wells in the drilling interval of 2500–3500 m, having horizontal lateral shafts in the range of 750–1500 m, meanwhile the mean time between failures is not increased, and significant economic advantages of the well-known designs.

An object of the invention is to increase the reliability and life of the stator of a screw gerotor hydraulic machine when used in a downhole motor for drilling oil wells by increasing fatigue resistance, abrasion resistance, elasticity and tightness of the working pair seal: rotor lining made of elastomer in the stator by preventing cracking, delamination and tearing pieces of the lining in the input and output parts in the stator due to the fact that the lining of the elastomer is upstream from the edges of the inner helical teeth directed against the flow, made with an inlet damper made of elastomer with its own internal helical teeth with the possibility of fastening with a lining, the side surfaces of the internal helical teeth of the tubular body, directed against the flow, and the inner surface of the inlet part of the tubular body, and also due to that downstream from the edge of the internal helical teeth, the lining is made with an output damper made of elastomer with its own internal helical teeth, with the possibility of scratching lining with the lining, the lateral surfaces of the internal helical teeth of the tubular body, directed downstream, and the inner surface of the upstream part of the tubular body.

Another technical objective of the invention is to increase the accuracy of drilling of deviated and horizontal wells, to increase the rate of a set of parameters of well curvature, and also to improve cross-flow ability, i.e. reduction of resistance and stresses in the layout of the bottom of the drill string when used in a hydraulic downhole motor by reducing the stiffness of the tubular casing - making the wall of the tubular casing in the inlet and outlet parts with a belt of reduced stiffness, characterized by a reduced thickness, which ensures bending of the stator tubular body when passing through radius sections of the wellbore having sections of small and medium radius of 30 ÷ 300 m, in conditions of intense friction along the wellbore.

The essence of the technical solution lies in the fact that in the stator of a screw gerotor hydraulic machine, for example, a motor for rotating the rotor from the pump fluid supply or a pump for supplying fluid by rotating the rotor containing a tubular body with an inner surface made in the form of a helicoid with internal helical teeth , on each edge of the tubular body an internal thread is made, as well as an elastomer lining fixed in the tubular body adjacent to the inner surface of the tubular body a mustache, the elastomer lining is made with internal helical teeth and coincides in shape with the internal helical teeth in the tubular body, and the thickness of the lining is maximum on the teeth radially directed inward, while the maximum thickness of the lining of the elastomer along the hollows of its internal helical surface in the tubular body located at the maximum radial distance is equal to half the height of its internal helical teeth, and the minimum wall thickness of the tubular body along radially outward the hollow of its internal helical surface is equal to the height of the internal helical teeth in the elastomer plate, according to the invention, the elastomer plate contains in the upstream part of the tubular body, upstream from the edge of the internal helical teeth directed upstream, the inlet damper of the elastomer with its own internal helical teeth adjacent to the internal helical teeth of the elastomer plate, adjacent to the inner surface of the upstream part of the tubular body with the possibility of bonding with the elastomer lining, the side surfaces of the internal helical teeth of the tubular body, directed against the flow, and the inner surface of the inlet part of the tubular body, while downstream from the edge of the internal helical teeth of the tubular body in the downstream part of the tubular body, the elastomer lining contains an output an elastomer damper with its own internal helical teeth adjacent to the internal helical teeth of the elastomer lining, located inside the tubular body, adj gayuschy to the inner surface of the discharge flow from the tubular body portion

the possibility of bonding with the lining of the elastomer, the side surfaces of the internal helical teeth of the tubular body, directed downstream, and the inner surface of the upstream part of the tubular body, while the minimum thickness of the inlet and outlet dampers from the elastomer along the troughs of their internal helical teeth located at the maximum radial removal, equal to the thickness of the lining of the elastomer on its teeth radially directed inward.

The stator contains in the upstream part of the tubular body a belt of reduced stiffness, characterized by the execution of the wall of the tubular body of reduced thickness, located between the edge of the internal helical teeth of the front annular damper, directed against the flow, and the complete last turn of the internal thread of the inlet part of the tubular body, and the downstream part of the tubular body contains a belt of reduced stiffness, characterized by the execution of the wall of the tubular body with a reduced thickness, located married between the edge of the internal helical teeth of the outlet damper made of elastomer and the total last thread of the internal thread in the downstream part of the tubular body, while the ratio of the reduced wall thickness of the tubular body in the upstream part of the tubular body, as well as in the downstream part of the tubular body the outer diameter of the tubular body is 0,065 ÷ 0,095.

The execution of the stator of the screw gerotor hydraulic machine in such a way that it contains in the upstream part of the tubular body, upstream from the edge of the internal helical teeth directed upstream, an inlet damper made of elastomer with its own internal helical teeth adjacent to the internal helical teeth of the plate made of elastomer adjacent to the inner surface of the upstream part of the tubular body with the possibility of fastening with a lining of elastomer, the side surfaces of the internal helical teeth of the pipe the casing body, directed against the flow, and the inner surface of the upstream part of the tubular casing, while downstream from the edge of the internal helical teeth of the tubular casing in the downstream part of the tubular casing, the elastomer lining contains an output damper made of elastomer with its own internal spiral teeth, adjacent to the internal helical teeth of the plate made of elastomer, located inside the tubular body adjacent to the inner surface of the upstream part of the tubular body with the possibility of bonding with the lining of the elastomer, the lateral surfaces of the internal helical teeth of the tubular body, directed downstream, and the inner surface of the upstream part of the tubular body, while the minimum thickness of the inlet and outlet dampers of the elastomer along the valleys of their internal helical teeth located at the maximum radial removal, equal to the thickness of the lining of the elastomer on its teeth radially directed inward, provides increased fatigue endurance, abrasion resistance and, the elasticity and tightness of the sealing of the working pair: the rotor lining of the elastomer in the stator by preventing cracking, delamination and tearing of pieces of the lining of the elastomer in the inlet and outlet fluid flow portions of the lining of the elastomer in the stator, thereby increasing reliability and resource the stator of a screw gerotor hydraulic machine when used in a hydraulic downhole motor for drilling oil and gas wells in conditions of high turbulence of the drilling fluid, which has a density l up to 1500 kg / m ³ , contains up to 2% of sand and up to 5% of oil products, due to the prevention of blockage of the flushing unit of the drill bit, essentially due to the prevention of the main failure of the layout of the bottom of the drill string (BHA) when drilling wells due to - " rubber in the bit ", as a result of this, the required interval of the well can be finished to the end, the MTBF is increased, and significant economic advantages of the claimed design are provided.

The design of the stator of a screw gerotor hydraulic machine in such a way that it contains a belt of reduced stiffness in the inlet part of the tubular body, characterized by the execution of the wall of the tubular body of reduced thickness, located between the edge of the internal helical teeth of the front annular damper, directed against the flow, and the complete last turn of the internal thread the upstream part of the tubular body, and in the downstream part of the tubular body contains a belt of reduced stiffness, characterized the execution of the wall of the tubular body of reduced thickness, located between the edge of the internal helical teeth of the output damper from the elastomer and the complete last turn of the internal thread in the downstream part of the tubular body, while the ratio of the reduced wall thickness of the tubular body in the upstream part of the tubular body, as well as the downstream part of the tubular body to the outer diameter of the tubular body is 0.065 ÷ 0.095, which improves the accuracy of penetration of inclined and horizontal wells n, increasing the pace of a set of parameters of well curvature, as well as improving patency, i.e. reducing the resistance and stresses in the layout of the bottom of the drill string when used in a hydraulic downhole motor by reducing the stiffness of the tubular body - making the wall of the tubular body in the inlet and outlet fluid flow parts with a belt of reduced stiffness, characterized by a reduced thickness, which ensures bending of the stator tubular body when passing through the radial sections of the wellbore having sections of small and medium radius of 30 ... 300 m, in conditions of intense friction along the wellbore wells.

Below is the best design option for a stator with the same thickness of the plate of elastomer (R-Wall) of the engine section of the downhole motor DRU2-172 PC for drilling oil wells.

In FIG. 1 shows a longitudinal section through the stator of a screw gyratory hydraulic motor.

In FIG. 2 shows a section AA in FIG. 1 across the inlet damper of elastomer in the inlet of the tubular body, the number of helical teeth of the inlet damper is 7.

In FIG. 3 shows a section BB in FIG. 1 across the tubular body with internal helical teeth and an elastomer cover, the number of helical teeth of the cover and the housing is 7.

In FIG. 4 shows a section BB in FIG. 1 across the outlet damper from the elastomer in the outlet of the tubular body, the number of helical teeth of the outlet damper is 7.

In FIG. 5 shows a longitudinal section through a motor section including a rotor installed inside the inlet damper, the lining and the outlet damper, all of elastomer, inside the tubular body.

In FIG. 6 shows a section GG in FIG. 5 across the engine section, including the input damper of the elastomer and the rotor, the ratio of the number of teeth of the rotor-input damper is 6/7.

In FIG. 7 shows a section DD in FIG. 5 across the motor section, including a stator with an elastomer lining and a rotor, the ratio of the number of teeth of the rotor lining is 6/7.

In FIG. 8 shows a section EE in FIG. 5 across the engine section, including the output damper from the elastomer and the rotor, the ratio of the number of teeth of the rotor-output damper is 6/7.

The stator of a screw gerotor hydraulic machine, for example a downhole screw motor for rotating the rotor from the pump fluid supply (drilling fluid), comprises a tubular body 1 with an inner surface 2 made in the form of a helicoid, essentially with internal helical teeth 3, on the fluid inlet flow medium 4, the edge 5 of the tubular body 1 has an internal conical pipe thread 6, for example, РКТ154х6.35х1: 9.6 СТП 001-2007, and the inner conical pipe thread is made at the fluid outlet 4 edge 7 of the tubular body 1 8, for example, PKT154x6.35x1: 9.6 STP 001-2007, and also contains a lining 9 of elastomer fixed in a tubular body 1, for example, of IRP-1226-5 rubber, adjacent to the inner surface 2 of the tubular body 1, while 9 of the elastomer is made with internal helical teeth 10 and coincides in shape with the internal helical teeth 3 in the tubular body 1, and the thickness 11 of the lining 9 is maximum on its teeth 10 radially inward, compared with the thickness of 12 depressions 13 along the internal helical surface 14 of said plate 9, fig. azheno FIG. 1, 2, 4.

In the tubular casing 1, the maximum thickness 12 of the plate 9 of elastomer along the troughs 13 of its inner helical surface 14 located at a maximum radial distance of 15 is equal to half the height 16 of its inner helical teeth 10, while the minimum thickness 17 of the wall of the tubular casing 1 is along the radially outward the depressions 18 of its internal helical surface 2 is equal to the height 16 of the internal helical teeth 10 in the lining 9 of elastomer, shown in figures 1, 2, 4.

The elastomer lining 9 comprises in the inlet stream 4 parts 5 of the tubular body 1, upstream 4 from the edge 19 of the internal helical teeth 3 in the tubular body 1, directed against the stream 4, the inlet damper 20 of the elastomer with its own internal helical teeth 21 adjacent to the internal helical teeth 10 of the plate 9 of elastomer, adjacent to the inner surface 22 of the inlet 4 parts 5 of the tubular body 1, with the possibility of fastening with the lining 9 of elastomer, the side surfaces 23 of the internal helical teeth 3 are tubular the body 1, directed against the flow 4, and the inner surface 22 of the inlet 4 of the pipe 5 of the tubular body 1, while the side (frontal) surface 24 of the inlet damper 20 of elastomer with its own internal helical teeth 21, directed against the flow of fluid 4, made in the form of a chamfer 25, which reduces the hydraulic resistance of the plate 9 of the elastomer in the fluid stream 4 and prevents cracking and delamination of the inlet edge 26 in the inlet damper 20 of the elastomer in the fluid stream 4 (drilling fluid ) Inside the tubular body 1 shown in FIG. 1, 2, 3.

Downstream 4 from the edge 27 of the internal helical teeth 3 of the tubular body 1 to the downstream 4 parts 7 of the tubular body 1, the elastomer plate 9 comprises an output damper 28 of the elastomer with its own internal helical teeth 29 adjacent to the internal helical teeth 10 of the plate 9 of an elastomer located inside the tubular body 1, adjacent to the inner surface 30 of the downstream 4 parts 7 of the tubular body 1 with the possibility of fastening to the lining 9 of the elastomer, lateral (rear in the flow of fluid) surface by the threads 31 of the internal helical teeth 3 of the tubular body 1, directed downstream 4, and the inner surface 30 of the downstream 4 parts 7 of the tubular body 1, while the side (rear downstream of the fluid) surface 32 of the internal helical teeth 26 of the output damper 25 of the elastomer directed along the flow of fluid 4 is made in the form of a chamfer 33, which reduces the hydraulic resistance (in the area of the reverse currents of the fluid) of the output damper 28 from the elastomer and prevents cracking and delamination of the output edge 34 in the output mpfere 28 of the elastomer in the fluid stream 4 (mud) inside the tubular body 1 shown in FIG. 1, 3, 4.

The minimum thickness 35 of the inlet damper 20 from the elastomer along the depressions 36 of its internal helical teeth 21 located at a maximum radial distance of 37 is equal to the thickness 11 of the plate 9 of elastomer on its teeth 10 radially inward, shown in FIG. 1, 2, 3.

The minimum thickness 38 of the output damper 28 from the elastomer along the troughs 39 of its internal helical teeth 29 located at a maximum radial distance 40 is equal to the thickness 11 of the plate 9 of the elastomer on its teeth 10 radially inward, shown in FIG. 1, 3, 4.

The stator contains in the inlet 4 parts 5 of the tubular body 1 a belt 41 of reduced stiffness, characterized by the execution of the wall 42 of the tubular body 1 with a reduced thickness of 43, located between the edge 26 of the internal helical teeth 21 of the front annular damper 20 directed against the flow 4 and the last complete turn 44 of the internal thread 6 of the inlet stream 4 of part 5 of the tubular body 1, shown in FIG. 12.

The stator contains in the outlet stream 4 parts 7 of the tubular body 1 a belt 45 of reduced stiffness, characterized by the execution of the wall 46 of the tubular body 1 with a reduced thickness 47, located between the edge 34 of the internal helical teeth 29 of the output damper 28 made of elastomer and the complete last turn 48 of the internal thread 8 the outlet stream 4 of part 7 of the tubular body 1 is shown in FIG. fourteen.

The ratio of the reduced thickness 43 of the wall 42 of the tubular body 1 in the inlet 4 of the pipe part 5 5 of the tubular body 1, as well as the ratio of the reduced thickness 47 of the wall 46 of the tubular body 1 in the 4 outlet 7 of the tubular body 1 to the outer diameter 49 of the tubular body 1 is 0.065 ÷ 0.095, shown in FIG. 1, 2, 4.

The motor section includes a rotor 50 having helical teeth 51, the number of teeth 51 of the rotor 50 is one less than the number of teeth 10 of the lining 9 of elastomer, as well as the number of teeth 21 of the input damper 22 from the elastomer, as well as the number of teeth 29 of the output damper 28 from the elastomer , the ratio of the number of teeths of the rotor 50 is the lining 9 of the elastomer, and also the rotor 50 is the input damper 22 of the elastomer, as well as the rotor 50 is the output damper 28 of the elastomer is 6/7, while pos. 52 is the central longitudinal axis of the rotor 50, item 53 is the central longitudinal axis of the lining 9 of elastomer fixed inside the tubular body 1, as well as the input damper 20 of the elastomer, and the output damper 28 of the elastomer, while pos. 54 is the magnitude of the eccentricity of the rotor 50 installed in the plate 9 of elastomer inside the tubular body 1, bonded to the inner surface of the tubular body 1, and also installed in the inlet damper 20 of the elastomer, as well as installed in the output damper 28 of the elastomer, shown in FIG. 6, 7, 8, 9.

The hardness of the lining 9 of elastomer, as well as input and output ring dampers, respectively, 20 and 28, for example from rubber IRP-1226-5, is 75 ± 3 units. Shore A.

In addition, item 55 - multi-helical chambers between the teeth 51 of the rotor 50 and the teeth 21 of the input damper 20 of the elastomer, pos. 56 - multi-helical chambers between the teeth 51 of the rotor 50 and the teeth 10 of the lining 9 of elastomer, pos. 57 - multi-start screw chambers between the teeth of the rotor 50 and the teeth 29 of the output damper 28 from the elastomer are shown in FIG. 6, 7, 8.

A stator with a uniform thickness of the plate 9 made of elastomer (R-Wall) is included in the engine module of a downhole screw motor for drilling an oil well, including a cardan transmission and a spindle section with a drill bit (not shown).

The design of the stator when used in a downhole screw motor for drilling a well works as follows: the mud stream 4 under pressure, for example, 25 + 35 MPa, is supplied through the drill pipe string to multi-helical chambers 55 between the teeth 51 of the rotor 50 and the teeth 21 of the inlet damper 20 of elastomer in the fluid inlet - drilling fluid 4 of part 5 of the tubular body 1, then into the multi-helical chambers 56 between the teeth 51 of the rotor 50 and the teeth 10 of the lining 9 of the elastomer fixed inside the tubular body 1, further into the multi-helical screw chambers 57 between the teeth 51 of the rotor 50 and the teeth 29 of the output damper 28 in the downstream fluid 4 of the part 7 of the tubular body 1,

Multiple screw chambers 55 between the teeth 51 of the rotor 50 and the teeth 21 of the inlet damper 20 from the elastomer in the fluid inlet - drilling mud 4 of the pipe part 5 5, multi-start screw chambers 56 between the teeth 51 of the rotor 50 and the teeth 10 of the lining 9 of elastomer, fixed inside the tubular body 1, as well as multi-helical screw chambers 57 between the teeth 51 of the rotor 50 and the teeth 29 of the output damper 28 in the downstream fluid 4 parts 7 of the tubular body 1, have a variable volume and periodically move along the stream 4 fluid - a drilling fluid, which has a density of up to 1500 kg / m ³ , contains up to 2% sand and up to 5% of oil products, while a high pressure region and torque from hydraulic forces are formed, which leads to a planetary rotor rotation 50 inside the inlet damper 20 of elastomer with its own internal helical teeth 21 adjacent to the internal helical teeth 10 of the lining 9 of elastomer in the inlet 4 of the pipe 5 of the tubular body 1, inside the lining 9 of elastomer with internal helical teeth 10, as well as inside the outlet damper 28 from an elastomer with its own internal helical teeth 29 in the outlet stream 4 of part 7 of the tubular body 1.

The rotor 50, under the action of a pumping fluid supply, transmits torque to the shaft of the spindle section with a bit in the opposite direction relative to its own planetary-rotor rotation inside the inlet damper 20 from the elastomer in the inlet 4 of the pipe part 5, inside the lining 9 of the elastomer fixed in the tubular body 1, as well as inside the outlet damper 28 from an elastomer with its own internal helical teeth 29 in the downstream part 4 of the tubular body 1, 7, while drilling a well.

Spiral teeth 21 of the inlet damper 20 from elastomer in the inlet stream 4 of part 5 of the tubular body 1, helical teeth 10 of the elastomer cover fixed inside the tubular body 1, and also helical teeth 29 of the outlet damper 28 in the downstream part 4 of the tubular body 1 subjected to complex deformation and bending during planetary-rotor rotation of the rotor 50 inside the inlet damper 20 from the elastomer in the inlet fluid stream - drilling mud 4 of the 5 parts of the tubular body 1, inside the lining 9 of the elastomer fixed in the tubular m the housing 1 and the damper 28 within the outlet of an elastomer with internal helical teeth 29 to the output 4 downstream portion 7 of the tubular body 1.

In the claimed design due to the fact that the lining 9 of the elastomer contains in the inlet stream 4 parts 5 of the tubular body 1, upstream 4 from the edge 19 of the internal helical teeth 3 in the tubular body 1, directed against the stream 4, the input damper 20 from the elastomer with their own internal helical teeth 21 adjacent to the internal helical teeth 10 of the lining 9 of elastomer, adjacent to the inner surface 22 of the inlet 4 of the pipe 5 of the tubular body 1, with the possibility of fastening with the lining 9 of elastomer, side surfaces 23 internal helical teeth 3 of the tubular body 1, directed against the stream 4, and an inner surface 22 of the inlet 4 parts 5 of the tubular body 1, while the side (frontal) surface 24 of the input damper 20 is made of elastomer with its own internal helical teeth 21, directed against the fluid flow 4, made in the form of a chamfer 25, which reduces the hydraulic resistance of the plate 9 of elastomer in the fluid flow 4 and prevents cracking and delamination of the inlet edge 26 in the inlet damper 20 of the elastomer in the fluid stream 4 (drilling fluid) inside the tubular body 1, while downstream 4 from the edge 27 of the internal helical teeth 3 of the tubular body 1 to the downstream 4 part 7 of the tubular body 1 lining 9 of elastomer contains an output damper 28 of elastomer with their own internal helical teeth 29 adjacent to the internal helical teeth 10 of the plate 9 made of elastomer, placed inside the tubular body 1, adjacent to the inner surface 30 of the downstream 4 part 7 of the tubular body 1 with the possibility of fastening with a lining 9 of elastomer, lateral (rear in the flow of fluid) surfaces 31 of the internal helical teeth 3 of the tubular body 1, directed downstream 4, and an inner surface 30 of the upstream 4 parts 7 of the tubular body 1, while the side (rear downstream ) the surface 32 of the internal helical teeth 26 of the outlet damper 25 from the elastomer directed along the fluid flow 4 is made in the form of a chamfer 33, which reduces the hydraulic resistance (in the region of the reverse currents of the fluid) of the outlet damper 28 from the elastomer and prevents As a result of cracking and delamination of the outlet edge 34 in the outlet damper 28 from the elastomer in the fluid flow 4 (drilling fluid) inside the tubular body 1, zones of increased shear strength are provided, a temperature gradient is reduced when heat is generated inside the tooth material from the elastomer, internal heat is improved the inlet damper 20 from the elastomer, the plates 9 from the elastomer, as well as the outlet damper 28 from the elastomer to the fluid flow 4 inside the tubular body 1, and also through the walls of the tubular of the body 1 to the drilling fluid from the outside of the tubular body 1 (annulus), the flow of which is directed from the bottom (from the bit) to the wellhead.

As a result, the elastomeric properties of the elastomer in the structure are increased: fatigue endurance during alternating bending with rotation (GOST 10952-75), permanent deformation and fatigue endurance during repeated compression (GOST 20418-75), temperature limit of brittleness (GOST 7912-74), abrasion at slip (GOST 426-77), the likelihood of cracking, peeling and tearing of pieces of the lining of the elastomer in the inlet and outlet upstream parts of the lining of the elastomer in the stator is reduced, blocking of the drilling flushing unit to lot, eliminates the main failure of the layout of the bottom of the drill string (BHA) when drilling wells for the reason - "rubber in the bit", while the required interval of the well can be completed to the end, the mean time between failures is increased, significant economic advantages of the claimed design are provided.

In the claimed design due to the fact that the stator contains in the inlet 4 of part 5 of the tubular body 1 a belt 41 of reduced stiffness, characterized by the execution of the wall 42 of the tubular body 1 with a reduced thickness of 43, located between the edge 26 of the internal helical teeth 21 of the front annular damper 20 directed against the stream 4, and the complete last turn 44 of the internal thread 6 of the inlet 4 of the 5 parts of the tubular body 1, and also due to the fact that the stator contains in the outlet 4 of the 7 parts of the tubular body 1 belt 45 lowered stiffness, characterized by the execution of the wall 46 of the tubular body 1 with a reduced thickness of 47, located between the edge 34 of the internal helical teeth 29 of the output damper 28 from elastomer and the complete last turn 48 of the internal thread 8 in the downstream part 4 of the tubular body 1, and the ratio of the reduced thickness is 43 the walls 42 of the tubular body 1 in the inlet stream 4 of the part 5 of the tubular body 1, the ratio of the reduced thickness 47 of the wall 46 of the tubular body 1 in the outlet 4 of the part 7 of the tubular body 1 to the outer diameter 49 of the tubular body 1 is 0.065 ÷ 0.095, an increase in the accuracy of drilling of deviated and horizontal wells is provided, an increase in the rate of the set of parameters of the curvature of the wells, as well as an improvement in the throughput, i.e. reducing the resistance and stresses in the layout of the bottom of the drill string when used in a hydraulic downhole motor by reducing the stiffness of the tubular body - making the wall of the tubular body in the inlet and outlet fluid flow parts with a belt of reduced stiffness, characterized by a reduced thickness, which ensures bending of the stator tubular body when passing through the radial sections of the wellbore having sections of small and medium radius of 30 ... 300 m, in conditions of intense friction along the wellbore wells.

EFFECT: invention increases reliability and resource when used in a downhole hydraulic motor for drilling curved wells by increasing fatigue endurance, abrasion resistance, elasticity and tightness of a working pair seal: rotor lining made of elastomer in the stator by preventing cracking, delamination and tearing of pieces of lining from the elastomer into the input and output parts of the elastomer plate in the stator, thereby preventing clogging of the flushing assembly of the drill bit, as a result of which the required inte well breakage can be completed to the end, MTBF is increased, and significant economic advantages of the claimed design are provided.

The invention also improves the accuracy of drilling of deviated and horizontal wells, the pace of a set of parameters of well curvature, and also improves cross-flow ability, i.e. reduces the resistance and stress in the layout of the bottom of the drill string when used in a hydraulic downhole motor by reducing the rigidity of the tubular body - making the wall of the tubular body in the input and output parts with a belt of reduced stiffness, characterized by a reduced thickness, which ensures bending of the tubular body when passing through radius sections the wellbore in conditions of intense friction along the wellbore.

Claims (2)

1. The stator of a screw gerotor hydraulic machine, for example, a motor for rotating a rotor from a pump fluid supply or a pump for supplying a fluid by rotating the rotor, comprising a tubular body with an inner surface made in the form of a helicoid with internal helical teeth, on each edge of the tubular body internal thread, as well as an elastomer lining fixed in the tubular body adjacent to the inner surface of the tubular body, the elastomer lining is made with internal teeth and coincides in shape with the internal helical teeth in the tubular body, and the thickness of the lining is maximum on the teeth radially directed inward, while in the tubular body the maximum thickness of the lining of elastomer along the hollows of its internal helical surface located at the maximum radial distance is half the height of its internal helical teeth, and the minimum wall thickness of the tubular body along the radially outward troughs of its internal helical surface is equal to the heights the internal helical teeth in the elastomer lining, characterized in that the elastomer lining contains in the upstream part of the tubular body, upstream from the edge of the internal helical teeth, directed upstream, the inlet damper of the elastomer with its own internal helical teeth adjacent to the internal helical the teeth of the lining of elastomer adjacent to the inner surface of the upstream part of the tubular body with the possibility of bonding with the lining of the elastomer, the side surfaces of the inner x of the helical teeth of the tubular body directed against the flow, and the inner surface of the inlet part of the tubular body, while downstream from the edge of the internal helical teeth of the tubular body in the downstream part of the tubular body, the elastomer cover contains an output damper of elastomer with its own internal helical teeth adjacent to the internal helical teeth of the elastomer lining, located inside the tubular body adjacent to the inner surface of the downstream part the tubular body with the possibility of bonding with the lining of the elastomer, the lateral surfaces of the internal helical teeth of the tubular body, directed downstream, and the inner surface of the upstream part of the tubular body, while the minimum thickness of the inlet and outlet dampers of the elastomer along the troughs of their internal helical teeth located at maximum radial distance, equal to the thickness of the lining of the elastomer on its teeth radially directed inward. 2. The stator of a screw gerotor hydraulic machine according to claim 1, characterized in that it comprises a belt of reduced stiffness in the inlet part of the tubular body, characterized by a reduced thickness of the tubular body wall located between the edge of the internal helical teeth of the front annular damper directed against the flow, and the complete last turn of the internal thread of the upstream part of the tubular body, and in the downstream part of the tubular body contains a belt of reduced stiffness, characterized by the wall of the tubular body with reduced thickness located between the edge of the internal helical teeth of the output damper from the elastomer and the last complete thread of the internal thread in the downstream part of the tubular body, the ratio of the reduced wall thickness of the tubular body in the inlet part of the tubular body, as well as the downstream part of the tubular body to the outer diameter of the tubular body is 0.065 ÷ 0.095.

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