RU2710338C1 - Hydraulic downhole motor - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to hydraulic drives for rotary drilling located in a well. Hydraulic downhole motor comprises a stator, which is a tubular body with an elastomer-coated in it coating of an elastomer, adjacent to the inner surface of the tubular body, the elastomer liner is made with internal helical teeth, at each edge of the tubular body there is an internal thread and a rotor inside the stator with external helical teeth, the number of rotor helical teeth per unit is less than the number of helical teeth of the lining, the paths of the helical teeth of the lining and the rotor are proportional to their number of teeth, and central longitudinal axes of rotor and cover are offset to each other by value of eccentricity. Cross sections of external helical teeth at the edges of the rotor are outlined by an equidistant profile which decreases in the direction of the near end of the rotor, which is configured to shift each point of the profile in a radial direction along a vector connecting each point of the profile to the central longitudinal axis of the rotor, length L of each section of external helical teeth on the edges of the rotor, which is outlined by the equidistant profile in the direction of the near end of the rotor, and the radius R of the outer surface of the rotor on the length between the said sections are related by the relationship: L=(3.55÷5.55)R, wherein radius R_t each point of profile of outer surface of rotor on length of each section L on edges of rotor, on which outer helical teeth cross sections are outlined with equidistant profile decreasing in direction of rotor near end face, made with possibility to shift each profile point in radial direction along vector connecting each profile point to central longitudinal axis of rotor, and radius R_c each point of the profile of the external surface of the rotor on the length between the said sections, corresponding to each point of the profile on the length of each section L on the edges of the rotor along the vector connecting each point of the profile to the central longitudinal axis of the rotor, are related by the relationship: R_t=(0.85÷0.98)R_c.

EFFECT: increasing service life and reliability of the engine by reducing stresses along edges of the elastomer plate in the stator housing, thereby preventing cracking, peeling and breakage along the edges of the coating, where increased amount of heat is generated and stored from action of rotor twisting moments at its planetary-rotary rotation inside the lining, preventing drilling node clogging of drilling bit, required interval of well can be drilled to the end, economic advantages are provided for directed drilling of wells.

1 cl, 9 dwg

Description

The invention relates to hydraulic actuators for rotary drilling, placed in the well, in particular to hydraulic downhole motors for drilling oil wells.

A known hydraulic screw mechanism used as a pump or motor, comprising a stator housing and a rotor, the rotor having an external helical surface, the stator housing is made in the form of a monolithic rigid tubular element having a cylindrical outer surface and an inner surface, as well as helical teeth, this said mechanism contains a flexible layer made of elastomer having the same thickness on the inner surface of the housing (US 2005/0079083 A1, 04/14/2005).

In the known screw hydraulic mechanism, a flexible layer made of an elastomer undergoes deformation and bending during planetary-rotor rotation of the rotor inside the stator, which leads to the formation on the protrusions and troughs of the helical teeth of the flexible layer of zones that differ from each other in terms of contact pressure, shear strength, hardness (elasticity) and thermal conductivity.

The temperature in the flexible layer (lining) of the elastomer 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 temperature increase.

A disadvantage of the known design is the incomplete possibility of increasing the resource and reliability when using as a hydraulic downhole motor for drilling oil wells, as well as maximum power, the moment of force on the output shaft in the mode of maximum power and fatigue endurance (resource) of the lining of the elastomer is 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 drilling fluid inside the housing, as well as through the walls of the body to the flow of drilling fluid with cuttings in the annulus space, the formation in the centers of the tooth profile of the lining of the elastomer 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 of the teeth of the plate becomes less flexible (brittle and brittle), the mechanical properties of the elastomer in the center of the profile of the teeth of the plate are reduced, while the pressure acting in the chambers between the rotor and the stator isolated and moving along the flow of fluid can exceed the shear strength of the elastomer , and the tops of the teeth in the lining can be deformed and torn off the body.

Known stator for a hydraulic downhole motor, forming an outer pipe with an inner surface made of at least two internal helical teeth (or blades), an elastomer cover fixed to the housing adjacent to the inner surface of the outer pipe, the lining being made with internal helical teeth (or blades), coincides in shape with the internal helical teeth (or blades) in the outer tube, and the thickness of the lining is maximum on the teeth (or blades), radially directed GOVERNMENTAL inwardly, at least two (US 6,604,921 B1, 14.04.2005).

The disadvantages of the known design are explained by the incomplete possibility of increasing the resource and reliability of the hydraulic downhole motor, maximum power, the moment of force on the output shaft in the maximum power mode and the fatigue endurance (resource) of the elastomer 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 internal helical teeth of the lining in comparison with the depressions of the helical teeth of the lining.

The temperature in the lining of the elastomer 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 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 design are explained by the incomplete possibility of optimizing the thickness of the lining along the hollows of the internal helical surface and the minimum wall thickness of the outer pipe 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 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, which leads to an increased gradient at a temperature in the allocation of heat within the electrode material and disturbance of interference in the working pair, to discharge internal heat deterioration of the electrode of the elastomer to the flow of drilling fluid within the housing, and through the outer wall of the pipe to the flow of drilling fluid from drill cuttings in the annulus.

Due to the heat generated in the centers of the lining of the elastomer in the form of teeth, secondary polymerization occurs: molecular crosslinking of the elastomer (rubber), which leads to degradation of the material, as a result, the center profile of the teeth of the lining of the elastomer becomes inflexible (brittle and brittle), mechanical properties the elastomer in these areas is deteriorating, while the pressure acting in the chambers between the rotor and the stator may exceed the shear strength of the elastomer, and the tops of the stator lining can be deformed and tear off baleen.

Known is the stator of a screw gerotor hydraulic machine, essentially an engine for rotating the rotor from the pump fluid supply, comprising an outer pipe with an inner surface made in the form of a helicoid with internal helical teeth, an elastomer lining fixed to the outer pipe adjacent to the inner surface of the outer pipe, while the lining is made with internal helical teeth and coincides in shape with the internal helical teeth in the outer pipe, and the thickness of the lining is maximum on the teeth, the radial but directed inwardly in the outer pipe, the maximum thickness of the elastomer lining along the depressions of its inner helical surface located at the maximum radial distance is equal to half the height of its internal helical teeth, and the minimum wall thickness of the outer pipe along the radially outward depressions of its inner helical surface is equal to the height internal helical teeth in the lining of elastomer (RU 2373364 C2, 11/20/2009).

The main defects that reduce the reliability and resource of a known design: cracking, delamination, as well as tearing of pieces of the lining from the elastomer (rubber) from the side of the inlet and outlet of the fluid (drilling fluid) in tough operating conditions (when drilling in hard rock): if the working pair between the rotor and the lining of the tubular body of the necessary interference contact pressure is 2.5 ÷ 3 MPa, the sliding speed is 0.5 ÷ 2.5 m / s, the hydrostatic pressure can reach 50 MPa, and the torque on the output shaft in max mode maximum power 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% sand and up to 5% of oil products, which leads to the cessation of circulation, while the main reason for failure the layout of the bottom of the drill string (BHA), in which a hydraulic downhole motor with a spindle and a chisel is installed, is "rubber in chisel".

The development of these defects is facilitated by high working pressure drops, internal heat generation in the stator lining material, braking of the working pair of the engine during operation, high interference in the working pair of the engine (rotor lining made of stator elastomer).

An increase in the length of the working pair section allows one to reduce the level of contact loads in the engagement of the working pair of the engine and to prevent premature destruction of the lining of the elastomer along the edges of the stator.

At the same time, the energy characteristics of the engine, reliability and resource are increased.

However, an increase in the length of the working pairs of the engine (rotor - stator lining) worsens the permeability of the layout of the bottom of the drill string when passing through the radius sections of the borehole while drilling the horizontal interval of the deviated well.

Due to the peculiarities of the operation of the gerotor mechanisms of screw hydraulic machines, an increased amount of heat is generated and stored on the edges of the elastomer lining in the stator during the rotor warping moments during rotor planetary rotation of the rotor inside the teeth of the elastomer lining in the stator.

As a result, the center of the profile becomes less flexible (brittle and brittle), the mechanical properties of the elastomer (rubber) deteriorate in these areas, 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 or tear themselves away from the stator housing, the possibility of increasing the maximum power, the moment of force on the output shaft in the maximum power mode and the fatigue endurance (resource) of the elastomer plate is reduced - at least 100 thousand cycles .

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

As a result, 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, the economic advantages of the known construction are not provided.

The disadvantages of the known design are explained by the incomplete possibility of optimizing the thickness of the plate from the elastomer along the sides of the plate from the elastomer, which leads to a deterioration in the removal of internal heat from the plate from the elastomer to the drilling fluid flow inside the casing, as well as through the casing walls to the drilling fluid flow with cuttings in the annulus space, the formation in 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, due to e this does not provide the properties of the elastomer in the design, essentially 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 during sliding (GOST 426-77).

As a result, the center of the profile profile of the teeth from the elastomer plate becomes less flexible (brittle and brittle), the mechanical properties of the elastomer (rubber) deteriorate in these areas, the pressure acting in the chambers between the rotor and the stator can exceed the shear strength of the elastomer, while the tops of the teeth , as well as the lateral surface of the teeth in the lining of the elastomer are deformed and torn away from the body.

The main defects that reduce the reliability and life of the hydraulic downhole motor, in which the stator is made with the same thickness of the elastomer plate (R-Wall): cracking of the plate from the elastomer (rubber) at the edges, from the side of the inlet and outlet of the fluid (drilling fluid), delamination plates of elastomer at the edges, from the side of the inlet and outlet of the fluid, as well as tearing pieces of the plate from elastomer in the middle of the stator and along the edges in the inlet and outlet upstream parts of the plate from elastomer in the stator under stressful conditions oty (when drilling in hard rock): if there is a necessary interference between the rotor and the tubular body lining, the contact pressure is 2.5–3 MPa, the sliding speed is 0.5–2.5 m / s, and the 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% sand and up to 10% oil products, which leads to the cessation of circulation, while the main Jicin failure of the BHA, which is installed with the spindle motor, and the skew angle regulator bit - "in the bit tires".

Known stator of a screw gerotor hydraulic machine, essentially an engine for rotating the rotor from the pump fluid supply, containing a tubular body with an inner surface made in the form of a helicoid with internal helical teeth, an internal thread is made on each edge of the tubular body, and also containing fixed in the tubular the casing is made of elastomer adjacent to the inner surface of the tubular casing, the casing of elastomer is made with internal helical teeth and coincides in shape with the internal and helical teeth in a 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 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 wall thickness of the tubular body along the radially outward troughs of its internal helical surface is equal to the height of the internal helical teeth in the lining of elasto the measure, while the stator contains in the inlet stream of the tubular body part a damper cavity located downstream from the edge of the internal helical teeth in the tubular body, directed against the flow, made in the form of an annular groove inside the tubular body adjacent to the side surfaces of the internal helical teeth of the tubular the housing formed by said annular groove, and the lining of the elastomer contains in said damper cavity an inlet damper of elastomer with its own internal helical tooth holes adjacent to the internal helical teeth of the elastomer plate, adjacent to the surface of the annular groove inside the tubular body and the lateral surfaces of the internal helical teeth of the tubular body formed by said annular groove, with the possibility of bonding with the lining of the elastomer, as well as with the ring groove inside the tubular body and the lateral surfaces of the internal helical teeth of the tubular body formed by the said annular groove, and the minimum distance from directed against the flow of the edge of the internal helical teeth in the upstream part of the tubular body to the input edge of the inlet damper is equal to the thickness of the input damper from the elastomer on its internal helical teeth radially inward, while downstream from the edge of the internal helical teeth in the downstream part of the tubular the casing of the elastomer contains an outlet damper of elastomer with its own internal helical teeth adjacent to the internal helical teeth of the lining of the elastomer adjacent to the inner the surface of the downstream part of the tubular body with the possibility of fastening to the lining of the elastomer 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 distance is equal to the thickness of the lining from an elastomer on its teeth radially directed inward (RU 2652725 C1, 04/28/2018).

The main advantages of a stator with its own helical teeth and the same thickness of the plate made of elastomer (R-Wall):

the stator load capacity is increased, hysteresis losses in the lining are reduced, the 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 destruction ("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 bits (Polycrystalline Diamond Compakt) 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 finished to the end, the mean time between failures (Journal of Drilling and Oil, 11/2014, p. 56 ÷ 59) .

There is a well-known schedule for the development of engines of the Radius-Service company, which is part of Schlumberger, which worked with StingBlade bits (Fig. 6). The data are presented for a dimension of 172 mm, the drilling interval reached 2000 m. Analyzing it, we can see that 200 hours are not a problem even for standard Radius-Service engines. Drilling and Oil Magazine, No. 4, 2018, Gumich D.P. et al., "Drilling in one flight ...".

The main defects that reduce the life and reliability of a known downhole motor, in which a known stator is made with the same thickness of the elastomer plate (R-Wall): cracking of the plate of elastomer (rubber) from the fluid outlet side (drilling fluid), peeling of the plate from the elastomer ( rubber) from the side of the fluid outlet, as well as tearing of pieces of the lining from the elastomer (rubber) in the downstream part of the lining from the elastomer in the stator under intense working conditions (when drilling in hard rocks): if there is a working pa between the rotor and the lining of the tubular body of the necessary interference, the contact pressure is 2.5–3 MPa, the sliding speed is 0.5–2.5 m / s, the hydrostatic pressure can reach 50 MPa, and the torque 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% 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 columns (BHA) in the cat swarm installed with the spindle motor, and the skew angle regulator bit - "in the bit tires".

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 tips of the teeth the plate is deformed or detached from the body, while reducing the possibility of increasing the maximum power, the torque on the output shaft in the maximum power mode and the fatigue endurance (resource) of the plate made of elastomer - ie less than 100 thousand cycles.

As a result of this, 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), sliding abrasion (GOST 426-77).

где Z_р и Z_с - числа зубьев ротора и соответственно обкладки, а координаты X_с, У_с номинального профиля обкладки определены выражениями:Closest to the claimed design is a gerotor mechanism of a screw hydraulic machine containing a stator, which is a tubular body with a lining made of elastomer, for example, rubber, with internal helical teeth and a rotor located inside the stator with external helical teeth, the number of which is one less the number of teeth of the lining, the moves of the helical teeth of the lining and the rotor are proportional to their number of teeth, and the central longitudinal axis of the rotor and the lining are offset by an amount of exce trisiteta, wherein the end face profile of teeth in coated elastomer is outlined as an envelope curve radii r _s by rotating the coordinate system X _axes and Y _axes, which belongs to a circle of radius r _s, and the center of a circle of radius r _s is located on a circle with R _oC radius drawn from the center of the coordinate system X _OS , Y _OS , and the center of the coordinate system X _OS , Y _{OS is} offset from the central longitudinal axis of the plate by the amount of eccentricity a _w between the central longitudinal axes of the rotor and plate and is defined by the expression: R _oc = r _if -r _s - a _w , where r _if is the radius cavities of the teeth of the plate, the angle of rotation of the coordinate system X _OS , Y _OS relative to the fixed coordinate system X _k , Yk, the center of which is located on the central longitudinal axis of the plate, and the angle of rotation Ψ _c of the coordinate system X _s , Y _s , whose center is located on the central the axis of the plate, relative to the fixed coordinate system X _k , Y _k , are related by the relation:

where Z _p and Z _c - the number of teeth of the rotor and, respectively, the lining, and the coordinates X _c , Y _{from the} nominal profile of the lining are defined by the expressions

при этом торцовый профиль зубьев ротора очерчен как огибающая кривая радиусов r_m при повороте системы координат X_ор, У_ор, которой принадлежит окружность радиуса r_m, а центр окружности радиуса r_m расположен на окружности с радиусом R_ор, проведенным из центра системы координат X_op, У_ор, причем центр системы координат X_op, У_ор смещен от центральной продольной оси ротора на величину эксцентриситета a_w и определен выражением:

wherein the end face profile of teeth of the rotor is outlined as an envelope curve radii r _m when rotating coordinate system X _op V _op, which belongs to a circle of radius r _m, and the center of radius r circumferential _m located on a circle with radius R _op drawn from the center of the coordinate system X _op , У _ор , and the center of the coordinate system X _op , У _{Ор is} offset from the central longitudinal axis of the rotor by the eccentricity a _w and is defined by

системы координат X_ор, У_ор относительно неподвижной системы координат X_кр, У_кр, центр которой расположен на центральной продольной оси ротора, и угол поворота Ψ_р системы координат X_р, У_р, центр которой расположен на центральной продольной оси ротора относительно неподвижной системы координат X_кр, У_кр, связаны соотношением:

где Z_р - число зубьев ротора, а координаты X_р, У_р номинального профиля ротора определены выражениями:R _op = g _if -r _m -2a _w , and the rotation angle

coordinate system X _op , Y _op relative to the fixed coordinate system X _cr , Y _cr , the center of which is located on the central longitudinal axis of the rotor, and the angle of rotation Ψ _p of the coordinate system X _p , U _p , the center of which is located on the central longitudinal axis of the rotor relative to the fixed system coordinates X _kr , Y _kr are related by the relation:

where Z _p - the number of teeth of the rotor, and the coordinates X _p , Y _{p the} nominal profile of the rotor are defined by the expressions:

(RU 2309237 C1, 10.27.2007).

The disadvantages of the known design are explained by the main defects that reduce the resource and reliability of the known gerotor mechanism of a screw hydraulic machine used in a hydraulic downhole motor for drilling oil wells: cracking, delamination, and also tearing pieces of the lining from the elastomer (rubber) from the side of the fluid inlet ( drilling fluid), under stressful operating conditions (when drilling in hard rock): if there is the necessary pair in the working pair between the rotor and the lining of the tubular body contact pressure is 2.5–3 MPa, sliding speed 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 installed hydraulic downhole motor with spindle lem, a skew angle regulator and a chisel - "rubber in a chisel".

Due to the peculiarities of the operation of the gerotor mechanisms of screw hydraulic machines at the edges of the elastomer plate in the stator housing, an increased amount of heat is generated from the action of the distorting moments of the rotor during its planetary-rotor rotation inside the teeth of the plate from the elastomer in the stator housing at maximum power.

Due to another feature of the operation of gerotor mechanisms of screw hydraulic machines when used in a downhole motor when drilling inclined and horizontal intervals of wells along the edges of the lining of elastomer in the stator housing, an increased amount of heat is generated and stored due to bending of the tubular motor housing when passing through the radius intervals of the well bore, having sections of small and medium radius 30 ÷ 300 m, in conditions of intense friction along the wellbore.

As a result of this, 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), sliding abrasion (GOST 426-77).

Another disadvantage of the known design used in a downhole hydraulic motor for drilling oil wells is the incomplete possibility of increasing reliability and service life by providing equal strength and tight threaded connections in the input and output parts of the tubular body with an adapter and / or adapter in difficult drilling conditions of inclined and horizontal intervals of wells in hard rocks, causing high working pressure drops, internal heat generation in the body lining material, torus the life of the working couple during operation, high tension in the working couple, as well as in conditions of intense friction and rotation in the wellbore, using hydraulic jars in the drill pipe string, with shock loads and impulses from the jars, as well as during tensile stress relaxation in the bent string drill pipe in which a downhole hydraulic motor is installed.

The mentioned drawback of the known construction is explained by the increased rigidity of the inlet and outlet parts of the tubular body when used in a downhole hydraulic motor, essentially by a large value of the stress coefficient during bending (Stress ratio, the ratio of the changing voltage amplitude to the average voltage) at the joints of the threaded joints of the tubular body with sub and / or adapter equal to 7 ÷ 9, as well as a high probability of cracking on the threads and breakage of the threaded connection in the input and output the first parts of the tubular body when using the downhole motor in horizontal controlled layouts of the bottom of the drill string, in areas where the curvature of the deviated well changes, mainly in the maximum power mode.

Due to the increased rigidity in the input and output parts of the tubular body of the downhole motor, it is not completely possible to increase the accuracy of the drilling of inclined and horizontal intervals of the wells, to increase the rate of the set of parameters of the curvature of the wells, and also to improve throughput, i.e. reducing the resistance and stresses in the layout of the bottom of the drill string due to the bending of the tubular engine casing 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, while the mean time between failures is not provided, and significant economic advantages are not provided known design.

The technical result that is provided by the invention is to increase the resource and reliability of the hydraulic downhole motor for drilling oil wells by preventing cracking, delamination and tearing of pieces of the lining from the elastomer in the stator housing along the edges of the lining of the elastomer, essentially in the areas where it is produced and stored increased amount of heat from the action of the distorting moments of the rotor during planetary-rotor rotation of the rotor inside the teeth of the lining of elastomer in the stator housing, due to the fact that the cross-sections of the helical teeth at the edges of the outer surface of the rotor are made with an equidistant profile decreasing in the direction of the near end of the rotor, which allows reducing stresses along the edges of the elastomer plate in the stator housing under alternating bending with rotation and multiple compression.

Another technical result that is provided by the invention is to increase the accuracy of the drilling of deviated and horizontal intervals of the wells, to increase the rate of the set of parameters of the curvature of the wells, as well as to improve the throughput, i.e. in reducing the resistance and stresses in the layout of the bottom of the drill string by reducing the rigidity of the tubular body by performing in the input and output parts of the body of belts of reduced stiffness, characterized by the execution of the wall of the body of reduced thickness, with the possibility of bending of the body when passing through the radius of the borehole.

The essence of the technical solution lies in the fact that in a hydraulic downhole motor containing a stator, which is a tubular body with an elastomer cover fixed to it, adjacent to the inner surface of the tubular body, the elastomer cover is made with internal helical teeth, on each edge of the tubular body internal thread, and a rotor with external helical teeth located inside the stator, the number of helical teeth of the rotor is one less than the number of helical teeth of the lining, screw moves x of the teeth of the lining and the rotor are proportional to their number of teeth, and the central longitudinal axis of the rotor and the lining are offset by the eccentricity, according to the invention, the cross sections of the outer helical teeth at the edges of the rotor are outlined by a decreasing profile in the direction of the near end of the rotor made with the possibility of displacement of each point of the profile in the radial direction along the vector connecting each point of the profile with the central longitudinal axis of the rotor, the length L of each section of the external helical teeth a rotor edges contoured decreasing toward the proximal end of equidistant rotor profile, and the radius R of the outer surface of the rotor over a length between said portions are related by: L = (3,55 ÷ 5,55) R, wherein R radius _r of each point of the outer profile the surface of the rotor along the length of each section L on the edges of the rotor, on which the cross sections of the external helical teeth are outlined by an equidistant profile decreasing in the direction of the near end of the rotor, which is capable of shifting each profile point in the radial direction enii the vector connecting each profile point with the central longitudinal axis of the rotor, and the radius R _at each point of the profile of the outer surface of the rotor over a length between said portions corresponding to each point of the profile over the length of each section L at the rotor ends along the vector connecting each dot profile with the central longitudinal axis of the rotor, are related by: R _m = (0,85 ÷ 0,98) R _c.

The downhole hydraulic motor comprises a belt of reduced stiffness, characterized by the execution of the wall of the tubular body with a reduced thickness, located between the edge of the facing of the elastomer directed against the flow and the last complete thread of the internal thread in the inlet the flow of the tubular body part, and in the downstream part of the tubular body contains a belt of reduced stiffness, characterized by the execution of the wall of the tube of the reduced body, located between the edge of the elastomer lining, directed downstream, and the last complete 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 output the flow of the tubular body to the outer diameter of the tubular body is 0.05 ÷ 0.09.

The execution of the hydraulic downhole motor in such a way that the cross sections of the external helical teeth at the rotor edges are outlined by an equidistant profile decreasing in the direction of the near end of the rotor, capable of shifting each profile point in the radial direction along the vector connecting each profile point with the central longitudinal axis of the rotor, length L of each section of external helical teeth at the edges of the rotor, outlined by a decreasing equidistant profile in the direction of the near end of the rotor, and a radius with R the outer surface of the rotor along the length between the mentioned sections are related by the relation: L = (3.55 ÷ 5.55) R, the radius R _{t of} each point of the profile of the outer surface of the rotor along the length of each section L at the edges of the rotor, on which the cross sections outer helical teeth delineated decreasing toward the proximal end of the rotor equidistant profile adapted to the profile of displacement of each point in the radial direction of the vector connecting each point of the profile with a central longitudinal axis of the rotor, and the radius R _from each point and the external surface of the rotor over a length between said portions corresponding to each point of the profile over the length L of each section at the edges of the rotor along vector connecting each profile point with the central longitudinal axis of the rotor, are related by: R _m = (0,85 ÷ 0,98 ) R _c increases the life and reliability of the hydraulic downhole motor for drilling oil wells by preventing cracking, delamination and tearing of pieces of the plate from the elastomer in the stator housing along the edges of the plate from the elastomer, essentially in the areas where you an increased amount of heat is generated and saved from the action of the rotor warping moments during planetary-rotor rotation of the rotor inside the teeth of the plate made of elastomer in the stator housing, which reduces stresses at the edges of the plate made of elastomer in the stator case during alternating bending with rotation and multiple compression.

The performance of the hydraulic downhole motor in such a way that the length L of each section of the external helical teeth at the edges of the rotor, outlined by a decreasing equidistant profile decreasing in the direction of the near end of the rotor, and the radius R of the outer surface of the rotor along the length between the said sections are related by the relation: L = (3.55 ÷ 5.55) R, the radius R _{t of} each point of the profile of the outer surface of the rotor along the length of each section L at the edges of the rotor, on which the cross sections of the outer helical teeth are outlined decreasing in the direction of the near the rotor end face with an equidistant profile made with the possibility of shifting each profile point in the radial direction along the vector connecting each profile point with the central longitudinal axis of the rotor, and the radius R _from each profile point of the outer surface of the rotor along the length between the said sections, corresponding to each profile point on the length of each section L at the edges of the rotor by a vector connecting each profile point with the central longitudinal axis of the rotor, are related by the ratio: R _t = (0.85 ÷ 0.98) R _s , provides the best properties of elast The structural element is essentially fatigue endurance in alternating bending with rotation (GOST 10952-75), permanent deformation and fatigue endurance in multiple compression (GOST 20418-75), temperature brittleness limit (GOST 7912-74), abrasion during sliding ( GOST 426-77), due to this, an increase in the resource and reliability of the hydraulic downhole motor in conditions of high turbulence of the drilling fluid, which has a density of up to 1500 kg / m ³ , contains up to 2% sand and up to 10% of oil products, is prevented from blocking washing unit of the drill bit and eliminates the main failure of the layout of the bottom of the drill string when drilling wells for the reason - "rubber in the bit."

The execution of the hydraulic downhole motor in such a way that it contains a belt of reduced stiffness in the inlet part of the tubular body with the elastomer lining fixed therein, characterized by the execution of the tubular body wall with a reduced thickness, located between the edge of the elastomer lining facing upstream and the last one a coil of internal thread in the inlet part of the tubular body, and in the downstream part of the tubular body contains a belt of reduced stiffness, character which is performed by the execution of the wall of the tubular body with a reduced thickness, located between the flow direction of the elastomer lining and the last complete 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 inlet part of the tubular body, and also in the downstream part of the tubular body to the outer diameter of the tubular body is 0.05 ÷ 0.09, increases the accuracy of the drilling of inclined and horizontal intervals of wells, the rate of boron parameters of the curvature of the wells, and also improves patency, i.e. reduces the resistance and stresses of the bottom of the drill string assembly by bending the engine casing when passing through the radius sections of the borehole under conditions of intense friction along the borehole, and also reduces the likelihood of fatigue cracks forming along the edges of the borehole while operating.

Below is the best version of the hydraulic downhole motor DRU2-172 PC for drilling oil wells.

In FIG. 1 shows a longitudinal section of an engine (option 1) including a rotor mounted inside a tubular body containing an elastomer lining.

In FIG. 2 shows a section AA in FIG. 1 across the inlet of the tubular body and rotor, the number of teeth of the rotor is 6, the number of teeth of the lining is 7.

In FIG. 3 shows a section BB in FIG. 1 across the tubular body and rotor, the number of teeth of the rotor is 6, the number of teeth of the lining is 7.

In FIG. 4 shows a section BB in FIG. 1 across the outlet of the tubular body and rotor, the number of teeth of the rotor is 6, the number of teeth of the lining is 7.

In FIG. 5 shows a longitudinal section of an engine (option 2), including a rotor mounted inside a tubular body made with its own helical teeth and the same thickness of the plate made of elastomer (R-Wall), as well as including input and output dampers from elastomer, made in one piece with lining.

In FIG. 6 shows a section GG in FIG. 5 across the inlet part of the tubular body with the inlet damper and the rotor, the number of teeth of the rotor is 6, the number of teeth of the inlet damper is 7.

In FIG. 7 shows a section DD in FIG. 5 across the tubular body with an elastomer lining and a rotor, the number of teeth of the rotor is 6, the number of teeth of the lining is 7.

In FIG. 8 shows a section EE in FIG. 5 across the outlet of the tubular body with the outlet damper and rotor, the number of teeth of the rotor is 6, the number of teeth of the outlet damper is 7.

In FIG. 9 shows a rotor for a downhole hydraulic motor, differing only in interference in the working pair for both motors (option 1 and 2), the cross sections at the edges of the rotor are made with a decreasing equidistant profile.

The downhole hydraulic motor (option 1) contains a stator, which is a tubular body 1 with an elastomer plate 2 fixed therein, with internal helical teeth 3, an internal conical pipe thread 6 is made on the edge of the fluid inlet 4 of the pipe 5, for example, for example , PKT154x6.35x1: 9.6 STP 001-2007, at the outlet of the fluid flow 4 the edge 7 of the tubular body 1 has an internal conical pipe thread 8, for example, PKT154x6.35xl: 9.6 STP 001-2007, as well as located inside stator rotor 9 with external helical teeth 10, the number of which is one less than the number of teeth 3 of the lining 2, the moves of the helical teeth 3 of the lining 2 and the helical teeth 10 of the rotor 9 are proportional to their number of teeth (not shown), and the central longitudinal axis 11 of the rotor 9 and the central longitudinal axis 12 of the lining 2 are shifted between by eccentricity 13, while pos. 14 - isolated screw chambers moving between the teeth 10 of the rotor 9 and the teeth 3 in the lining 2 of elastomer moving along the flow of the fluid 4 (drilling fluid), is shown in FIG. 1, 2, 3, 4, 9.

The helical line of the internal helical teeth 3 of the plate 2 made of elastomer inside the tubular body 1 is equal to the distance along the coaxial surface between the two positions of the point forming the line of the helical tooth 3, corresponding to its full revolution around the central longitudinal axis 12 of the tubular body 1, is shown, for example, in GOST 16530-83, p. 17.

The helical line of the outer helical teeth 10 of the rotor 9 is equal to the distance along the coaxial surface between the two positions of the point forming the line of the helical tooth 10 of the rotor 9, corresponding to its full revolution around the central longitudinal axis 11 of the rotor 9, shown, for example, in GOST 16530-83, p. . 17.

The number of helical teeth 3 in the lining 2 of the elastomer inside the tubular body 1 is 7, the direction of the helical teeth 3 in the lining 2 of the elastomer is left, the helical line of the teeth 3 in the lining 2 of the elastomer is 700 mm.

The number of external teeth 10 of the rotor 9 is 6, the direction of the external helical teeth 10 of the rotor 9 is left, the helical stroke of the external teeth 10 of the rotor 9 is 600 mm.

The hardness of the lining 2 of rubber grade R1 (DE) is 75 ± 3 units. Shore A.

The downhole hydraulic motor (option 2) contains a stator made, for example, according to patent RU 2652725 C1, 04/28/2018, with the same thickness of the lining of elastomer (R-Wall), which is a tubular body 15 with an inner surface 16 made in the shape of a helicoid essentially with internal helical teeth 17, on the edge 18 of the tubular body 15 at the inlet of the fluid 4, the conical pipe thread 19 is made, for example, PKT154x6.35x1: 9.6 STP 001-2007, at the outlet of the fluid 4 the edge 20 of the tubular body 1 is made inside conical pipe thread 21, for example, RKT 154x6.35x1: 9.6 STP 001-2007, and also contains a lining 22 of elastomer fixed in the tubular body 15, for example, of R1 (DE) rubber, adjacent to the inner surface 16 of the tubular case 15, while the lining 16 of the elastomer is made with internal helical teeth 23 and coincides in shape with the internal helical teeth 17 in the tubular body 15, and the thickness 24 of the lining 16 is maximum on its teeth 23 radially directed inward, compared with a thickness of 25 depressions 26 along the inner screw n surface 23 of said plate 22 made of elastomer, and also contains a rotor 27 located inside the stator with external helical teeth 28, the number of which is one less than the number of teeth 23 of plate 22, the moves of the screw teeth 23 of the plate 22 and screw teeth 28 of the rotor 27 are proportional to their number of teeth ( not shown), and the central longitudinal axis 29 of the rotor 27 and the central longitudinal axis 30 of the plate 22 are offset from each other by the amount of eccentricity 31, while pos. 32 - isolated screw chambers moving between the teeth of the rotor 27 and the teeth 23 in the elastomer plate 22, moving along the flow of fluid 4 (drilling mud), is shown in FIG. 5, 7.

The downhole hydraulic motor comprises a damper cavity 33 located in the inlet downstream of the fluid 4 (drilling fluid) of the part 18 inside the tubular body 15, located downstream 4 from the edge 34 of the internal helical teeth 16 of the tubular body 15, which is directed against the flow 4, made in the form of an annular grooves 35 (grooves) inside the tubular body 15 adjacent to the side surfaces 36 and 37 of the internal helical teeth 16 of the tubular body 15 formed by said annular groove 35 is shown in FIG. 5, 6.

The elastomer plate 22 contains in said damper cavity 33 an inlet damper 38 of elastomer with its own internal helical teeth 39 adjacent to the internal helical teeth 23 of the plate 22 of elastomer adjacent to the surface of the damper cavity 33, essentially an annular groove 35, inside the inlet the stream 4 of the part 18 of the tubular body 15, with the possibility of fastening with the lining 22 of the elastomer, as well as with the surface of the damper cavity 33, essentially an annular groove 35, and the side surfaces, respectively, 36 and 37 of the inner of their helical teeth 16 of the tubular body 15 formed by said annular groove 35 and the lateral surfaces 36 and 37 of the internal helical teeth 16 of the tubular body 15, respectively, is shown in FIG. 5, 6.

Downstream 4 from the edge 40 of the internal helical teeth 16 of the tubular body 15 to the downstream 4 parts 20 of the tubular body 15, the elastomer plate 22 comprises an output damper 41 of the elastomer with its own internal helical teeth 42 adjacent to the internal helical teeth 23 of the plate 22 of an elastomer having a surface 43 (in the form of an inner annular chamfer) in the downstream 4 parts 20 of the tubular body 1 with the possibility of fastening with the lining 22 of the elastomer and the inner surface 44 downstream 4 of the 20 pipe parts housing 15, is shown in FIG. 5, 8.

The number of internal helical teeth 16 of the tubular body 15, as well as internal helical teeth 23 in the lining 22 of the elastomer is 7, the direction of the internal helical teeth 16 of the tubular housing 15, as well as the internal helical teeth 23 in the lining 22 of the elastomer, is the left, the helical line of the internal helical teeth 16 of the tubular body 15, as well as internal helical teeth 23 in the lining 22 of the elastomer inside the tubular body 15 is 700 mm.

The helical line of the internal helical teeth 16 of the tubular body 15, as well as the internal helical teeth 23 of the elastomer plate 22 inside the tubular body 15 is equal to the distance along the coaxial surface between the two positions of the point forming the line of the internal helical tooth 16 of the tubular body 15, as well as the line of the internal helical tooth 23 in the lining 22 of elastomer, corresponding to its complete revolution around the central longitudinal axis 30 of the tubular body 15, is shown, for example, in GOST 16530-83, p. 17.

The hardness of the plate 22, the input damper 38 and the output damper 41 made of rubber grade R1 (DE) is 75 ± 3 units. Shore A.

In addition, pos. 45 - screw chambers moving downstream of fluid 4 (drilling fluid) between teeth 28 of rotor 27 and teeth 39 of inlet damper 38 of elastomer, item 46 moving 4 screw chambers between teeth 28 of rotor 27 and teeth of output damper 41, position 46 from an elastomer shown in FIG. 5, 6, 8.

For hydraulic downhole motor (option 1):

The cross sections of the external helical teeth 10 at the edge 47 of the rotor 9 are outlined by an equidistant profile, decreasing in the direction of the near end face 48 of the rotor 9, configured to offset each profile point 49 in a radial direction along the vector 50 connecting each profile point 49 with the central longitudinal axis 11 of the rotor 9 (with origin), shown in FIG. 1, 2, 9.

The cross sections of the external helical teeth 10 on the edge 51 of the rotor 9 are outlined by an equidistant profile decreasing in the direction of the near end 52 of the rotor 9 (an embodiment of the output edge of the rotor 9 with a diameter equal to the diameter of the teeth 10 of the rotor 9 is shown), made with the possibility of displacement of each point 53 of the profile in the radial direction along the vector 54, connecting each point 53 of the profile with the central longitudinal axis 11 of the rotor 9 (with the origin), while pos. 55 - the output of the outer helical teeth 10 on the edge 51 of the rotor 9, shown in Fig. 1, 4, 9.

The length L, 56 of each section of the outer helical teeth 50 and 54 at the edges of, respectively, 47 and 51 of the rotor 9, outlined by decreasing in the direction of the near end, respectively, 48 and 52, of the rotor 9 with an equidistant profile, and the radius R, 57 of the outer surface of the rotor 9 on a length 58 between the said sections 47 and 51 are connected by the ratio: L, 56 = (3.55 ÷ 5.55) R, 57, shown in FIG. 1, 2, 3, 4.

For hydraulic downhole motor (option 2):

The cross sections of the external helical teeth 28 on the edge 47 of the rotor 27 are outlined by an equidistant profile, decreasing in the direction of the near end face 48 of the rotor 27, made with the possibility of shifting each profile point 59 in the radial direction along the vector 50 connecting each profile point 59 with the central longitudinal axis 29 of the rotor 27 (with origin), shown in FIG. 5, 6, 9.

The cross sections of the outer helical teeth 28 on the edge 51 of the rotor 27 are outlined by an equidistant profile that decreases in the direction of the near end 52 of the rotor 27 (an embodiment of the output edge of the rotor 27 with a diameter equal to the diameter of the teeth 28 of the rotor 27 is shown), made with the possibility of displacement of each profile point 60 in the radial direction along the vector 54, connecting each point 60 of the profile with the Central longitudinal axis 29 of the rotor 27 (with the origin), while pos.55 - the output of the outer helical teeth 28 on the edge 51 of the rotor 27 is shown in city 5, 8, 9.

The length L, 56 of each section of the outer helical teeth 10 at the edges 47 and 51 of the rotor 9, outlined by decreasing in the direction of the proximal end, respectively, 48 and 52, the rotor 27 is an equidistant profile, as well as the length L, 56 of each section of the outer helical teeth 28 at the edges 47 and 51 of the rotor 27, outlined by decreasing in the direction of the near end, 48 and 52, respectively, of the rotor 27 with an equidistant profile, and the radius R, 57 of the outer surface of the rotor 27 at a length 58 between the said sections 47 and 51 are related by the relation: L (56) = (3.55 ÷ 5.55) R (57), shown in FIG. 1, 2, 3, 4, 5, 6, 7, 8, 9.

The cutting of helical teeth 10, 28 of the rotors 9, 27 (differing only in the interference of the working pair in the stator lining) is carried out on machines with programmed control of the Austrian company Weingartner.

For hydraulic downhole motor (option 1):

The radius R _t , 50 of each point 49 of the profile of the outer surface of the rotor 9 at the length of the section L, 56 at the edge 47 of the rotor 9 and the radius R _t , 54 of each point 53 of the profile of the outer surface of the rotor 9 at the length of the section L, 56 at the edge 51 of the rotor 9, on which the cross sections of the external helical teeth 10 are outlined by a decreasing in the direction of the near end face 48 and, accordingly, 52 of the rotor 9, made with the possibility of displacement of each point 49 and, correspondingly, 53 of the profile in the radial direction (to the origin, in essence, to central longitudinal axis 11 rotor 9) along the vector R _t , 50 connecting each point 49 of the profile with the central longitudinal axis 11 of the rotor 9, and also along the vector R _t , 54 connecting each point 53 of the profile with the central longitudinal axis 11 of the rotor 9, and the radius R _c , 61 of each profile point 62 of the outer surface of the rotor 9 at a length 58 between the said sections L, 56, corresponding to each profile point 49, 53 along the length of each section L, 56, at the edges 47 and 51 of the rotor 9, according to the vector R _t , 50 and, accordingly, the vector r _t, 54 each connecting point 49 and accordingly, the profile 53 with a central th longitudinal axis 11 of the rotor 9 are related by: R _m (50, 54) = (0,85 ÷ 0,98) R _s (61), shown in FIG. 1, 2, 3, 4, 9.

For hydraulic downhole motor (option 2):

The radius R _t , 50 of each point 59 of the profile of the outer surface of the rotor 27 at the length of the section L, 56 at the edge 47 of the rotor 27 and the radius R _t , 54 of each point 60 of the profile of the outer surface of the rotor 27 at the length of the section L, 56 at the edge 51 of the rotor 27, in which the cross sections of the outer helical teeth 28 are outlined by a decreasing equidistant profile in the direction of the near end 48 and, accordingly, 52 of the rotor 27, configured to offset each point 59 and, accordingly, 60 of the profile in the radial direction (to the origin, in essence, to central longitudinal os 29 rotor 27) of vector R _T, 50, connecting each point 59 profile with a central longitudinal axis 29 of the rotor 27, and the vector R _T, 54, connecting each point 60 profile with a central longitudinal axis 29 of the rotor 27 and the radius R _s, 63 of each point 64 of the profile of the outer surface of the rotor 27 at a length 58 between the said sections L, 56, corresponding to each point 59, 60 of the profile along the length of each section L, 56, at the edges 47 and 51 of the rotor 27, according to the vector R _t , 50 and, accordingly, along the vector R _t , 54 connecting each point 59 and, respectively, 60 of the profile with the center the longitudinal axis 29 of the rotor 27, are connected by the ratio: R _t (50, 54) = (0.85 ÷ 0.98) R _with (63), shown in FIG. 5, 6, 7, 8, 9.

The downhole hydraulic motor (option 1) contains, in the inlet stream 4 of part 5 of the tubular body 1, a belt of reduced rigidity 65, characterized by the execution of the wall 66 of the tubular body 1 of a reduced thickness 67, located between the edge 68 of the plate 2 of elastomer, fixed therein 2 from an elastomer directed against the stream 4, and the complete last turn 69 of the internal thread 6 in the inlet stream 4 of the part 5 of the tubular body 1, and in the outlet 4 of the part 4 of the tubular body 1 contains a belt 70 of reduced stiffness, characterized which is performed by the execution of the wall 66 of the tubular body with a reduced thickness 71, located between the edge 72 of the elastomer plate 2, directed downstream 4, and the complete last turn 73 of the internal thread 8 in the downstream part 4 of the tubular body 1, the ratio of the reduced thickness 67, 71 walls 66 of the tubular body 1 in the inlet stream 4 of part 5 of the tubular body 1, as well as in the outlet stream 4 of part 7 of the tubular body 1 to the outer diameter 74 of the tubular body 1 is 0.05 ÷ 0.09, shown in FIG. 1, 2, 3, 4.

The downhole hydraulic motor (option 2) contains in the inlet stream 4 parts 18 of the tubular body 15 with the inlet damper 38 fixed therein, the lining 22 and the outlet damper 41, all of the elastomer, a belt 75 of reduced stiffness, characterized by the execution of the wall 76 of the tubular body 15 reduced 77 thick, located between the edge 78 of the plate 22, including an inlet damper 38 made of elastomer, directed against the stream 4, and a complete last turn 79 of the internal thread 19 in the inlet stream 4 of the part 18 of the tubular body 15, and in the outlet section the current 4 parts 20 of the tubular body 15 contains a belt 80 of reduced stiffness, characterized by the execution of the wall 76 of the tubular body 15 with a reduced thickness of 81, located between the edge 82 of the elastomer plate 2, directed downstream 4, and the last complete turn 83 of the internal thread 21 into the downstream 4 parts 20 of the tubular body 15, the ratio of the reduced thickness of 77, 81 walls 76 of the tubular body 15 in the inlet stream 4 of the part 18 of the tubular body 15, as well as in the outlet stream 4 of the 20 parts of the tubular body 15 to the outer diameter of 84 tr casing 1 is 0.05 ÷ 0.09, shown in FIG. 1, 2, 3, 4.

Modern directional drilling systems usually use a drill string containing a bit located on the bottom, which is rotated by a volumetric action motor (downhole), while the hydraulic downhole motor includes a power section containing a stator and a rotor located in this stator.

The stator includes a metal tubular housing containing inside the lining of an elastomer having a helical profile of the teeth.

The rotor has a spiral profile with helical teeth made of metal.

The fluid (drilling fluid) is pumped under pressure into moving insulated cavities formed between the helical teeth of the rotor and the elastomer plates in the stator.

The force exerted by the drilling fluid pumped under pressure into the moving insulated cavities forces the rotor to press against the plate of the elastomer and rotate, making a planetary motion.

In this case, the torque on the engine rotor connected to the driveshaft, spindle and chisel is created in the opposite direction to the planetary rotation of the rotor inside the elastomer plate in the stator.

The elastomer lining in the stator provides a seal between the helical teeth of the stator and rotor, as well as a support for the rotor and is under high load during operation of the hydraulic downhole motor.

The operation of the hydraulic downhole motor (option 1) is as follows:

A downhole hydraulic motor containing a stator, which is a tubular body 1 with an elastomer plate 2 fixed therein, with internal helical teeth 3, an internal conical pipe thread 6, for example, PKT154x6, is made on the inlet of the fluid flow 4 to the edge 5 of the tubular body 1, 35x1: 9.6 STP 001-2007, at the outlet of the fluid flow 4 the edge 7 of the tubular body 1 has an internal conical pipe thread 8, for example, PKT154x6.3 5x1: 9.6 STP 001-2007, as well as a rotor located inside the stator 9 with external helical teeth 10, chi for which they are one less than the number of teeth 3 of the lining 2, the moves of the helical teeth 3 of the lining 2 and the helical teeth 10 of the rotor 9 are proportional to their number of teeth (not shown), and the central longitudinal axis 11 of the rotor 9 and the central longitudinal axis 12 of the lining 2 are offset by the amount of eccentricity 13, while pos. 14 - insulated helical chambers moving along the flow of fluid 4 (drilling fluid) between the teeth 10 of the rotor 9 and the teeth 3 in the cover 2 of elastomer are included in the engine module of the hydraulic downhole motor for directional drilling of oil wells, including a driveshaft, spindle section, skew angle adjuster between motor and spindle sections, and bit (not shown).

Spiral teeth 102 on the outer surface of the rotor 9 perform left-hand rotation to effect left-handed planetary-rotor rotation of the rotor 9 inside the lining 2 of elastomer fixed in the tubular body 1.

The working pair of the rotor-lining of the elastomer in the stator is in tense working conditions (when drilling in hard rock): if there is a necessary interference between the rotor 9 and the lining 2 of the tubular body 3, the contact pressure is 2.5 ÷ 3 MPa, sliding speed 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.

The hydraulic downhole motor for drilling directional oil wells works as follows: the mud flow 4 under pressure, for example, 25 ÷ 35 MPa, is supplied through the drill pipe string to multi-helical chambers 14 between teeth 10 of rotor 9 and teeth 3 of plate 2 of elastomer fixed inside of the tubular body 1, forms a region of high pressure and torque from hydraulic forces, which leads to planetary-rotor rotation of the rotor 9 inside the plate 9 of elastomer fixed in the tubular body 1.

Multiple screw chambers 14 between the teeth 10 of the rotor 9 and the teeth 10 of the plate 9 made of elastomer fixed inside the tubular body 1 have a variable volume and periodically move along the fluid flow - drilling mud 4, which has a density of up to 1500 kg / m ³ , contains up to 2% sand and up to 10% of petroleum products.

The planetary-rotor rotation (left) of the rotor 9 inside the elastomer plate 2, fixed inside the tubular body 1, transmits torque to the right through the drive (cardan) shaft, spindle section shaft, to the bit fixed in the coupling thread of the spindle section shaft (not shown ), carrying out directional well drilling.

In maximum power mode, the rotational speed of the shaft of the spindle section and bit is, for example, (1.8 ÷ 2.5) s ^-1 ; the moment of force on the shaft of the spindle section is (9 ÷ 14) kN⋅m; the pressure drop (inter-turn, on the teeth of the lining 2 from the elastomer into the housing 1) in the maximum power mode is 17 ÷ 28 MPa; maximum axial load (per bit) is 250 kN.

Screw plates 2 of elastomer fixed inside the tubular body 1 are subjected to complex deformation and bending during planetary-rotor rotation of the rotor 9 inside plates 2 of elastomer fixed in the tubular body 1.

Due to the operation of the hydraulic downhole motor along the edges of the plate 2 from the elastomer in the stator housing 1, an increased amount of heat is generated from the action of the distorting moments of the rotor 9 during its planetary-rotor rotation inside the teeth 3 of the plate 3 from the elastomer in the stator housing 1 in the maximum power mode.

Due to another feature of the operation of the hydraulic downhole motor during drilling of inclined and horizontal intervals of wells along the edges of the lining 2 from the elastomer in the stator housing 1, an increased amount of heat is generated and stored due to the bending of the tubular housing 1 of the motor when passing through the radius of the borehole having sections of small and medium radius 30 ÷ 300 m, in conditions of intense friction along the wellbore.

In the claimed design, due to the fact that the cross sections of the external helical teeth 10 on the edge 47 of the rotor 9 are outlined by an equidistant profile, decreasing in the direction of the near end face 48 of the rotor 9, configured to offset each profile point 49 in the radial direction along the vector 50 connecting each point 49 profile with the central longitudinal axis 11 of the rotor 9 (with the origin), while the cross sections of the outer helical teeth 10 at the edge 51 of the rotor 9 are outlined equidistant in the direction of the near end 52 of the rotor 9 a profile (an embodiment of the output edge of the rotor 9 with a diameter equal to the diameter of the teeth 10 of the rotor 9 is shown) configured to offset each profile point 53 in the radial direction along the vector 54 connecting each profile point 53 with the central longitudinal axis 11 of the rotor 9 (with the beginning coordinates), provides an increase in the resource and reliability of the hydraulic downhole motor for drilling oil wells by preventing cracking, delamination and tearing of pieces of the lining 2 from the elastomer in the stator housing 1 at the edges L, 56 masonry 2 of elastomer, essentially, in areas where an increased amount of heat is generated from the action of the distorting moments of the rotor 9 during planetary-rotor rotation of the rotor 9 inside the teeth 3 of the plate 2 of elastomer in the housing 1 of the stator, which allows to reduce stresses at the edges L , 56 plates made of elastomer in the housing 1 of the stator with alternating bending with rotation and multiple compression.

In the claimed design due to the fact that the length L, 56 of each section of the external helical teeth 50 and 54 at the edges of, respectively, 47 and 51 of the rotor 9, outlined by decreasing in the direction of the near end face, respectively, 48 and 52, of the rotor 9 with an equidistant profile, and the radius R, 57 of the outer surface of the rotor 9 at a length 58 between the said sections 47 and 51 are related by the ratio: L, 56 = (3.55 ÷ 5.55) R, 57, while the radius R _t , 50 of each point 49 of the profile of the outer surface rotor 9 over the length of portion L, 56 on the edge 47 of the rotor 9 and the radius r _t, 54 of each point 53 external surface p of the torus 9 along the length of the section L, 56 on the edge 51 of the rotor 9, on which the cross sections of the external helical teeth 10 are outlined by a decreasing in the direction of the near end face 48 and, accordingly, 52 of the rotor 9, made with the possibility of displacement of each point 49 and, accordingly, 53 of the profile in the radial direction (to the origin, essentially to the central longitudinal axis 11 of the rotor 9) along the vector R _t , 50 connecting each point 49 of the profile with the central longitudinal axis 11 of the rotor 9, as well as along the vector R _t , 54, connecting each point 53 of the profile with a central longitudinal axis 11 of the rotor 9, and a radius R _c , 61 of each profile point 62 of the outer surface of the rotor 9 at a length 58 between said sections L, 56, corresponding to each profile point 49, 53 along the length of each section L, 56, at the edges 47 and, accordingly, 51 rotors 9, along the vector R _t , 50 and, respectively, along the vector R _t , 54 connecting each point 49 and, correspondingly, 53 profiles with the central longitudinal axis 11 of the rotor 9, are connected by the ratio: R _t (50, 54) = (0.85 ÷ 0.98) R _s (61), the best properties of the elastomer in the structure are ensured, essentially fatigue resistance alternating bending with rotation (GOST 10952-75), permanent deformation and fatigue endurance during multiple compression (GOST 20418-75), temperature limit of brittleness (GOST 7912-74), abrasion during sliding (GOST 426-77), due to This provides an increase in the resource and reliability of the hydraulic downhole motor in conditions of high turbulence of the drilling fluid, which has a density of up to 1500 kg / m ³ , contains up to 2% sand and up to 10% of oil products, while blocking the drilling unit of the drill bit is prevented and the main the failure of the layout of the bottom of the drill string when drilling wells due to “rubber in the bit”, as a result of which the required interval of the well can be finished to the end, MTBF is increased, and the economic advantages of the claimed design are provided.

In the claimed design, due to the fact that the hydraulic downhole motor contains in the inlet stream 4 of part 5 of the tubular body 1 with a belt of reduced stiffness 65 fixed to it by an elastomer cover 2, characterized by the execution of the wall 66 of the tubular body 1 of a reduced thickness 67, located between the edge 68 plates 2 of elastomer directed against the stream 4, and the last complete turn 69 of the internal thread 6 in the inlet stream 4 of part 5 of the tubular body 1, and in the outlet stream 4 of part 7 of the tubular body 1 contains a belt 70 reduced stiffness, characterized by the execution of the wall 66 of the tubular body of a reduced thickness 71, located between the edge 72 of the plate 2 of the elastomer, directed downstream 4, and the last complete turn 73 of the internal thread 8 in the downstream 4 of part 7 of the tubular body 1, while the ratio is reduced thickness 67, 71 of the walls 66 of the tubular body 1 in the inlet 4 of the pipe part 5 of the tubular body 1, as well as in the outlet 4 of the pipe part 7 of the tubular body 1 to the outer diameter 74 of the tubular body 1 is 0.05 ÷ 0.09, the accuracy is improvedrohodki inclined and horizontal wells, the rate of collection wells curvature parameters and also improves the permeability, i.e. the resistances and stresses of the layout of the bottom of the drill string by bending the engine during passage through the radius of the borehole during intense friction along the borehole are reduced, and the likelihood of fatigue cracks at the edges of the body during production hours is reduced.

The use of a hydraulic downhole motor for drilling oil wells increases its life and reliability by reducing stresses on the edges of the lining during alternating bending with rotation and repeated compression, due to this, cracking, delamination and tearing of pieces of the lining from elastomer in the stator housing along the edges of the lining, where it is produced, are prevented and an increased amount of heat from the action of the distorting moments of the rotor is retained during planetary-rotor rotation of the rotor inside the lining in the stator housing, and however, the blockage of the flushing unit of the drill bit is prevented, as a result of which the required interval of the well can be finished to the end, and economic benefits are provided for directional drilling of wells.

The use of a hydraulic downhole motor also increases the accuracy of penetration when drilling directional 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 by reducing the rigidity of the body, ensuring bending of the body when passing through the radial intervals of the wellbore under conditions of intense friction along the wellbore, and also reduces the likelihood of fatigue cracks at the edges of the body.

Claims (2)

1. A downhole hydraulic motor comprising a stator, which is a tubular body with an elastomer casing fixed thereto adjacent to the inner surface of the tubular casing, an elastomer casing made with internal helical teeth, an internal thread is made on each edge of the tubular casing, and located inside the stator rotor with external helical teeth, the number of helical teeth of the rotor is one less than the number of helical teeth of the lining, the moves of the helical teeth of the lining and rotor are proportional to their numbers teeth, and the central longitudinal axis of the rotor and the plates are offset by an amount of eccentricity, characterized in that the cross sections of the external helical teeth at the edges of the rotor are outlined by an equidistant profile, decreasing in the direction of the near end of the rotor, made with the possibility of shifting each profile point in the radial direction along the vector connecting each profile point with the central longitudinal axis of the rotor, the length L of each section of the external helical teeth at the edges of the rotor, outlined by decreasing in the direction of the near end face of the rotor with an equidistant profile, and the radius R of the outer surface of the rotor along the length between the mentioned sections are related by the relation: L = (3.55 ÷ 5.55) R, with the radius R _{t of} each point of the profile of the outer surface of the rotor along the length of each section L at the edges of the rotor, on which the cross sections of the external helical teeth are outlined by an equidistant profile, decreasing in the direction of the near end of the rotor, made with the possibility of shifting each profile point in the radial direction along the vector connecting each profile point with the central longitudinal axis of the rotor, and the radius R _from each profile point of the outer surface of the rotor along the length between the mentioned sections, corresponding to each profile point on the length of each section L on the edges of the rotor along the vector connecting each profile point with the central longitudinal axis of the rotor, are related by the ratio: R _t = (0.85 ÷ 0.98) R _c . 2. The downhole hydraulic motor according to claim 1, characterized in that it comprises 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 plate of the elastomer directed towards against the flow, and the complete last turn of the internal thread in the upstream part of the tubular body, and in the downstream part of the tubular body contains a belt of reduced stiffness, characterizing reduced wall thickness, located between the flow direction of the elastomer lining edge 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, and also in the downstream part of the tubular body to the outer diameter of the tubular body is 0.05 ÷ 0.09.

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