RU2654560C1 - Plunger unit - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention relates to a volume-type pump with an engine, is designed for pumping liquid bodies, with the possibility of placement in wells. Plunger unit contains an engine kinematically connected to the screw drive of the plunger pump. Plunger pump contains a housing with suction and pressure valves. Inside the housing with the ability to rotate and with the possibility of mutual, relative along the axis of the housing movement, two double-sided plungers are installed. Plungers are connected to each other and to the housing, as well as to the motor shaft, screw drive. Screw drive is mounted, with the possibility of rotational movement in the housing, leading link – a screw with inclination angle α₁ screw line. Leading link – the screw is connected by the formation of a screw kinematic pair, with the driven link – a double-sided plunger, by means of a screw-threaded opening with slope angle α₁ a helical line made at the center of its bottom. Double-sided plunger has a hole in the center of its opposite bottom with a screw thread with angle of inclination α₂ screw line, which it is connected by the formation of a screw kinematic pair, with an output link – a screw. Output link – screw has a spiral thread with slope angle α₃ helical line, by means of which it is connected, by the formation of a screw kinematic pair, to the body. At the free end of the output link – screw is installed the another double-sided plunger. All screw cuts are of one direction. For screw lines, the inclination angles are: α₃<α₁<α₂. Linear dimensions of the helical grooves are interdependent to the movements of the links.

EFFECT: technical indicators are raised - pressure, flow, efficiency.

10 cl, 6 dwg

Description

The device "Plunger unit" is a volumetric type pump with an engine, designed to pump liquid bodies, with the possibility of placement in wells.

The device can be used in all industries, including:

in oil production during drilling, operation, well repair, to increase oil recovery;

in the chemical and petrochemical industry for pumping acids, ammonia, urea, melamine, and supplying reagents under pressure;

in the energy sector as a feed pump for a boiler plant of a steam generator;

in the food industry as a part of equipment for homogenization;

in mechanical engineering, for hydraulic presses;

in industries requiring high pressures, including explosive and fire hazardous;

in public utilities during repair, pressure testing of hydraulic systems and pipelines, during washing of the sewage system;

in steam field installations as a feed pump; in the gas industry; in agriculture.

In addition, the device can be mounted on special equipment, and can also be used on ships and boats of all classes as bilge, cleanup and other pumps.

Known reciprocating piston pumps - rocking machine. [Oilfield equipment. TsentrLitNefteGaz 2006]

Known reciprocating steam pumps [http://dic.academic.ru/dic.nsf/bse/118688/]. Their disadvantages are the need for generating and supplying steam to the pump, as well as the need for disposal of exhaust steam, which significantly reduces the efficiency of the device.

Unlike piston pumps, plunger pumps can operate at high pressures. This is due to the fact that, unlike piston pumps, where more accurate processing of the inner surface of the cylinder is of great importance, for plungers, high purity of processing should be on the side of the outer cylindrical surface, which is technologically simpler.

It is known (patent RU 147159, published October 27, 2014) to install a submersible plunger pump for lifting liquids from great depths, including a housing, a hydraulic immersion electric motor, the drive shaft of which is connected to a screw-nut rolling screw that is movably connected to the housing and connected to the piston rod of the pump plunger, the rod being sealed in the housing and connected to the rolling nut by means of a cylindrical hollow rod that encloses the screw and enters into the movable connection with it, and the internal cavity of the housing is filled and barrier oil, characterized in that the pump comprises a cylinder with a plunger movably connected to it, as well as a discharge valve and a suction valve located on the plunger head, and a cavity is formed between them, communicating with the cavity of the annulus of the well through receiving grids installed in the walls a cylinder of a plunger pump, wherein the submersible motor is made valve and its shaft is connected to the transmission screw screw-nut rolling through a bearing-bearing assembly located in the lower part of the housing over ca seal section, and a valve motor connected to a control station comprising a controller with embedded software.

For the above installation, the transmission screw-nut rolling can be made in the form of a roller-screw or ball-screw transmission.

The disadvantages of the installation is the need to use a reversible engine with a control system in the design, which significantly complicates the design and reduces reliability.

It is known (RU 2133875, published: 07.27.1999) a downhole sucker-rod pump drive, comprising an electric motor, a kinematically coupled two-way screw with a nut, rollers with a traction element, characterized in that the nut is mounted with the possibility of axial movement along a vertical rail, directly connected to rod string from below and from above - tubing string made in the form of a flexible connection; in addition, it is equipped with a balancing counterweight placed on a rack located coaxially with the that, with the rack height is greater than the length of the nut turn.

The disadvantages of the device are: design complexity; the need for vertical placement of at least the drive part of the device, as well as the possibility of its placement only outside the well; not high performance.

For plunger pumps, as well as for other volumetric pumps, flow and pressure pulsations are characteristic, which is a drawback. To reduce ripple, several plungers are arranged in a row, connected to one shaft, and the operation cycles should be shifted relative to each other in phase by equal angles. This design increases the transverse dimensions of the pump.

To reduce ripple, a differential pump switching circuit is also used. Here, due to the interconnection of the main working and rod cavities, fluid injection occurs both during the forward stroke of the plunger and during the reverse stroke. But such pumps do not have their own valve distribution system.

The double-sided pump has its own valve distribution system. Such pumps, in contrast to single-acting pumps, have a lower ripple coefficient and a higher efficiency.

The task to which the claimed invention is directed is the creation of a plunger assembly, the pump of which provides high technical indicators (pressure, flow) with a low ripple coefficient, has insignificant transverse dimensions, is capable of functioning together with any engine that allows to obtain torque from the shaft. Accordingly, the unit must have a higher efficiency, and autonomy.

The problem is solved through the use of a plunger pump in the design of the plunger assembly, the screw drive (mechanism) of which provides the ability to convert the unidirectional rotational movement of the drive shaft into the reciprocating motion of the two-way plungers in a single housing, as well as a valve distribution system that provides the possibility of uniform distribution of the pumped liquid or gas. By a screw mechanism, this possibility is achieved through the use of a jamming effect in various single-moving screw structural groups during rotation of the driving link - the screw.

The objective is achieved by the fact that according to the invention, the plunger assembly comprises a motor kinematically connected to a screw drive of the plunger pump,

wherein the plunger pump contains a housing with suction and pressure valves, inside of which, with the possibility of rotation and with the possibility of mutual, relative along the axis of the housing movement, two double-sided plungers are installed, connected to each other and the housing, as well as to the motor shaft, a screw drive formed and representing

installed, with the possibility of rotational movement, in the housing, the driving link is a screw having a tilt angle α _{1 of the} helix, connected by the formation of a helical kinematic pair, with a driven link - a double-sided plunger, by means of a screw thread with a tilt angle α _{1 of the} helix, taken along the center of its bottom, wherein this double-sided plunger apart screw thread with an angle of inclination α ₁ helix, the keeper opposite its bottom has an opening with a screw thread with an angle of inclination α ₂ helix to Ora it is bound, form a helical kinematic pair, the output link - screw, at the free end of which is mounted the other double-sided plunger output link - the screw has apart screw thread with an angle of inclination α ₂ helix screw thread with an angle of inclination α ₃ helix, by means of which it is connected, with the formation of a kinematic screw pair, with the body, while all screw threads are in the same direction, for helix lines the tilt angles are: α ₃ <α ₁ <α ₂ , and the linear dimensions of the screw threads are interdependent on the movements of the link ev

To reduce friction, increase efficiency, the screw mechanism can be ball screw or roller screw.

To support and fix the drive shaft of the screw drive in the plunger pump housing, as well as to provide rotation with the least resistance, to absorb radial and axial loads, the drive shaft of the screw drive of the plunger pump can be equipped with an angular contact bearing.

A cylindrical groove (cylinder) in the housing, in height, can have sections (parts) made with smaller diameters, while each smaller in diameter section (part) of the cylinder is made within the stroke of the plunger and in height not exceeding the dimensions of the largest solid inclusions in the medium pumped by the plunger.

The housing of the plunger pump may be cylindrical.

In the housing of the plunger pump can be made channels for supplying fluid to the seals of the plungers.

The material for the manufacture of the plunger pump housing may be steel. The material for the manufacture of plungers can serve as bronze.

The engine used in the unit may be electric.

In FIG. 1, FIG. 2 schematically shows a plunger assembly. The device comprises kinematically coupled motor 1 and a plunger pump by means of its screw drive. The motor 1 and the plunger pump with a screw drive can be installed in one (common) housing 3 or on a common frame. It is possible to implement a device in which a motor and a plunger pump with a screw drive are installed each in its own housing. For example, a plunger pump with a screw drive can be installed in one housing, and the engine is installed in another (own) housing or on a separate frame. It is possible to use a plunger pump without using an engine. In this case, muscular force is used to drive the screw drive, respectively the plungers.

Separate cases, and case 3 can be cylindrical. The housing 3 can be made detachable in various ways. For example, both end caps can be removable or one of them, the housing can be disconnected in any plane. The engine can be any, the design of which provides the ability to remove torque from the shaft. This may be an electric motor, an engine operating by means of liquid or gas, an internal combustion engine, etc. Depending on the design, engine 1 may be equipped with hydro protection, other protection or protection may not be necessary for the engine. By the degree of explosion protection of electrical equipment, an electric motor in general industrial design or an electric motor in explosion-proof design can be used. The plunger pump contains a drive part and a hydraulic part. The drive part contains a screw drive (mechanism) for converting the rotational motion of the motor shaft into the reciprocating motion of the plungers. The hydraulic part contains a cylinder (a cylindrical groove is made in the housing 3), plungers, suction and discharge valves, may contain plunger seals, safety valves.

A screw 2 of a screw drive (mechanism) is connected to the shaft of the engine 1, the output part, which functions as an input shaft. Accordingly, screw 2 is leading in the screw drive. Possible coaxial and non-coaxial connection of the motor shaft 1 with the screw 2. To transmit torque from the engine can be used cardan gear, constant velocity joint, gear coupling, belt drive. To increase the service life, the gear used can be sealed. To compensate for dynamic loads, the connection "motor shaft 1 - screw 2" can be equipped with a flexible or elastic coupling, for example, sleeve-finger. Flexible couplings can be used on the pump side with protection, on the motor side with protection. It is also possible to connect the motor shaft with screw 2 through the gearbox, through the gearbox with a heated housing. The end cover (or partition, if the engine and the plunger pump are in a single housing) of the housing 3 performs the function of supporting the output of the screw 2. To support and fix the output of the screw 2 in the housing 3, as well as to ensure rotation with the least resistance, perception of radial and axial loads, an angular contact bearing may be used. To protect the bearing, to prevent leakage of liquid or vapor, seals can be installed on the output of the shaft acting on the two sides of the bearing: mechanical; with manual adjustment; with spring pressure; stuffing box; cuffed; with a lock chamber and leak indicators.

In ground-based plunger pumps, cuffs can be added to the mechanical seal to prevent fluid leakage into the atmosphere. Leakage can also be routed to the suction line of the pump. At the same time, the liquid that seeps in a small amount through the mechanical seal serves as a lubricant and cools the friction parts of the seal; accordingly, it is not necessary to additionally supply oil to the seal.

With the screw 2, its first screw thread 4 (with an angle of inclination α _{1 of the} helix) in the hole made in the center of the bottom, is connected a plunger 5 mounted for rotation in the housing 3 (in a cylindrical groove made in the housing 3). Plunger 5 has two bottoms (i.e., is double-sided), in the center of each of which there is a threaded hole. Plunger 5 with its second screw thread (with an angle of inclination α _{2 of the} helix) in the hole made in the center of the opposite bottom is connected to the screw 7 with two screw threads, one of which with the angle of inclination α _{2 of the} helix, the other - α _{3 of the} helix . Thus, plunger 5 can be thought of as a “nut” with two different screw threads. The plunger 5 and the screw 7 form a helical kinematic pair of helical thread 6 (with an angle of inclination α _2, helix). Screw 7 and case 3 (the internal partition in the case, which is the support of screw 7, has a threaded hole in the center, with an angle of inclination of ₃ screw lines) form a kinematic screw pair with a screw thread 8. All screw threads in the same direction, for helical lines, tilt angles: α ₃ <α ₁ <α ₂ , and the linear dimensions of the screw threads are interdependent on the movements of the links.

At the free end of the screw 7, with the possibility of rotation relative to the housing 3, a plunger 9 is installed. The plunger 9 is two-sided, and is connected to the screw 7 pivotally or rigidly. In the case of a swivel, the screw 7 can rotate relative to the plunger 9. In the case of a rigid connection, the screw 7 rotates along with the plunger 9.

The cylinder (cylindrical groove in the housing 3) in height, may have sections (parts) 10, 11 made with smaller diameters (Fig. 2).

These are sections of the cylinder in the stroke area of the plunger 5 and in the stroke area of the plunger 9.

Each smaller section (part) of the cylinder in diameter is made within the stroke of the plunger and in height not exceeding the dimensions of the largest solid inclusions in the medium pumped by the plunger, that is, for plungers, sections (parts) 10 and 11 are both supports and guides.

This design of the cylinder allows the reciprocating movement of the plungers 5 and 9 with less friction and without distortions, in addition, the plungers, sections (parts) 10, 11, respectively, and the rest of the cylinder are less susceptible to wear by abrasive particles contained in the pumped medium.

For ease of repair, sections (parts) 10, 11 can be made in the form of removable bushings. The bushings can be pressed in or mounted with the possibility of relatively quick removal.

To prevent (reduce) leakage of the pumped gas, liquid, between each plunger and cylinder, in the grooves (grooves) made in the sections (parts) 10, 11, radial seals can be installed.

If the cylinder is executed in height with one diameter, to prevent (reduce) leakage of the pumped gas, liquid, between each plunger and cylinder, in grooves (grooves) made inside the cylinder, within the strokes of the plungers, radial seals can also be installed.

The plungers 5 and 9 in the housing 3 form three chambers "A", "B", "C" which can be connected by a pressure line 12. The chambers, through the suction valves 13, 14, 15, are able to communicate with the space outside the housing 3. Valves 13 , 14, 15 operate by discharge in the chambers "A", "B", "C". Also, these valves can be equipped with filters, and are connected by a suction line to the filter at the inlet. Valves 16, 17, 18 operate by means of pressure in chambers "A", "B", "C", i.e. are pressure head, and, provide the possibility of communication of the cameras with the pressure line 12. To reduce the radial dimensions of the device, the cross-section of the lines can be made segmented. Suction and discharge nozzles, single, twin, etc. can be used. made of carbon steel, non-ferrous metals, their alloys, plastic. The sequence of movement of the plungers resulting in a change in the volume of chambers "A", "B", "C" is determined by the kinematics of the screw pairs to which the plungers are connected. To eliminate sliding friction in a screw mechanism (helical gear), the latter can be implemented as ball screw or roller screw.

The plunger pump can be equipped with a safety valve, for example, a spring. In normal operation, it can be adjusted to both nominal and other operating pressures. Depending on the version, the plunger pump can be without a water seal or with a water seal.

To reduce the possible unevenness of the pumped fluid, the pressure line can be equipped with a hydraulic accumulator.

Depending on the application, the plunger pump can be provided with heating or cooling, as well as additional lubrication. Therefore, the hydraulic part in design can be:

with cooling (heating), lubrication of the hydraulic part, with a supply to the seals or to the working area of each of the plungers of lubricating, flushing, cooling or hydrolock fluid through channels made in the pump casing.

The plunger assembly can be connected to a device that controls the engine speed.

Material design of the pump.

The materials used for the manufacture of the hydraulic part of the plunger pump have the following requirements: high mechanical strength; low coefficient of linear expansion; high corrosion resistance; good anti-friction properties.

For the manufacture of sliding pairs (cylinder, plungers) it is possible to use steel, cast iron, bronze, alloys, and in various combinations, one part can be made of steel or cast iron, and a pair of it can be made of bronze, and vice versa.

Materials for cylinder and plungers:

chrome steel type 20X13 or 40X13 GOST 5632-72; GOST 5632-72 type 12X18H10T chromium-nickel steels; gray cast iron SCH 20, SCH 15; antifriction cast iron АЧК-2, АЧВ-2; forged carbon steels; duplex stainless steels; nickel-aluminum-bronze alloy;

bronzes: Br OF10-1, Br OTsS 6-6-3, Br AZh 9-4, etc., gray cast iron SCh 20, SCh 15, antifriction cast iron AChK-2, AChV-2.

The plungers may have a tungsten carbide coating; plungers for water are made with 45Ni60 surfacing. The plungers can be made of ceramic or coated with ceramic.

Valve.

Conical. Each of them can be made with a guide and loaded with a spring. By design, the suction valve and the discharge valve can be identical, which facilitates maintenance.

Valve and seat materials: stainless steel, e.g. 316 steel.

Stainless steel ball valves can be used for metering pumps.

Seal between plungers and cylinder.

By placing the plungers and their drive in a single cylinder (common to them), the plunger pump is able to function without any additional sealing elements between the plungers and the cylinder.

To prevent (reduce) leakage of gas, liquid between the plungers and the cylinder, in the grooves (grooves), inside the cylindrical part of the housing 3, radial seals 10, 11 can be installed, for example,

mechanical seals containing eccentric rings of antifriction material, which are ground to one another and pressed against the sealed surfaces of these elements in opposite directions, which are located in an elastic cage. The elastic clip is made of an elastomeric material, for example, rubber.

It is possible to use a seal (Fig. 2) containing o-rings (several pieces can be combined into cassettes), a L-shaped rubber cuff with eccentric collars, a protective support ring made of plastic, a metal clip. The L-shaped cuff provides a clamping of the sealing rings to each other and to the plunger, it is a dynamic seal in relation to the plunger (L-shaped protrusion) and static for the sealing rings.

Depending on the purpose of the pump, O-rings and other radial seals can be made of metals: bronze, brass, steel, alloys, incl. hard alloys, uncoated, and coated with chromium, zinc, copper; from wear-resistant plastics, other polymeric, composite materials. The L-shaped cuff is made of fluorine or nitrile rubber or polyurethane.

As mentioned above, in the housing of the plunger pump can be made channels for supplying lubricant to the seals of the plungers.

Screw drive (mechanism)

- converts the rotational motion of the motor shaft into the translational motion of the plungers. The screw drive (screw mechanism) of the plunger pump allows the rotation of screws 2 and 7 in any direction. Depending on the version, a thread can be used for a screw mechanism (screw-nut transmission): trapezoidal (with reverse load), persistent (with non-reverse load), and also rectangular, triangular, round, semicircular, arched. Also, depending on the design, the thread can be right, left, single and multi-start, non-self-braking.

Screws 2, 7 can be made integral or each of them can be made integral, for example, by screwing. The screws can be made of steel 45, 50, U10, 40X, 40HG, 40HGV, A40G, 65G, etc., followed by hardening to hardness HRC 50-55 and grinding of the working surfaces.

Each "nut" can be made in the form of a bronze sleeve one-piece or detachable. Two bushings are installed in the body of the plunger 5, and one in the partition in the housing 3. (the partition can also be detachable).

The bushings can be pressed in or mounted with the possibility of relatively quick removal. In the latter case, the bushings can be fixed in the body of the plunger, and in the partition of the housing using radially mounted clamping screws or pins. Detachable "nuts" - bushings, a split partition provide the ability to disassemble (assembly) faster.

Material of the “nut”: bronzes Br ОФ10-1, Br ОЦС 6-6-3, Бр АЖ 9-4, etc., gray cast iron СЧ 20, СЧ 15, antifriction cast iron АЧК-2, АЧВ-2.

Also, the plungers themselves, end caps, partitions in the housing 3 can be made of these materials, and without any bushings.

It is possible to perform a screw mechanism with a ball screw. In this case, the rolling screw-nut transmission is formed by balls placed between the screw surfaces of the screw and nut. When the screw rotates in one direction, the balls roll over and through the bypass channel in the nut (bypass channels can be made in the body of the plunger and in the partition) return to the working area.

Such a helical pair is not self-braking and can be used both to convert rotational motion to translational, and vice versa. In addition, such a transmission is characterized by high rigidity and accuracy, the ability to completely sample the gap, the ability to work without lubrication, low wear rate, high efficiency. The material of the screw can be steel 8XF, nuts - steel 9XC, heat treatment - surface hardening to hardness HRC 58-62.

The operation of the screw drive.

The screw drive of the plunger pump is a mechanism for converting rotational motion into reciprocating, that is, a screw mechanism, schematically shown in FIG. 3, FIG. 4, FIG. 5, FIG. 6, where its functioning is represented by several kinematic combinations of mobile links.

Such a screw mechanism comprises a leading link — a screw 2 mounted rotatably in a support (in the “left” end cover of the housing 3). Screw 2 forms a support kinematic rotational pair (VR.KP _3-2 ).

α ₁ - the angle of inclination of the helix of the screw 2.

An output link is connected to the driving link - screw 2 by means of a screw thread with an angle of inclination α _{1 of the} helical line - differential nut (plunger 5) having (th) two screw threads, where:

α ₁ angle of inclination of the helix of the nut (screw cutting of the plunger 5, the "left" part)

₂ α - helix angle nut (screw thread of the plunger 5, the "right" side)

A nut (plunger 5), by means of a screw thread with an angle of inclination α _{2 of the} helix, is connected to the output link - a screw 7 having two screw threads, one of which is with an angle of inclination α _{2 of the} helix, the other - α _{3 of the} helix.

Thus, the nut (plunger 5) forms the first helical kinematic pair (VKP _2-5 ) with the leading link - screw 2 and the second helical kinematic pair (VKP _5-7 ) with the output link - screw 7.

Screw 7 by means of its second screw thread with an angle of inclination a _{3 of the} helical line is connected to a support (with an internal partition in the housing, which is the support of screw 7) having a screw thread with an inclination angle α _{3 of the} helix, forming a third kinematic screw pair (VKP _7-3 )

All screw cuts in one direction, while the angles of inclination of the helix lines:

α ₃ <α ₁ <α _{2 ,.} The linear dimensions of the screw threads are interdependent on the movements of the links.

Kinematic screw pairs can form various combinations between themselves, which allows one-way rotation of the drive link - screw 2 to provide reciprocating movements of the output links - the nut (plunger 5) and screw 7. Providing the ability to convert one directional rotational movement of the drive link to the reciprocating the translational motion of the output links is solved by obtaining the possibility of transforming the mechanism structurally when the leading link - screw is rotated, using the jamming effect manure, in various single-movable screw structural groups.

When rotating the screw 2, the plunger 5 from the extreme position moves by the amount of stroke of the screw 2 in the direction of decreasing the volume of the chamber "A". Due to this, the working fluid is pumped through the valve 16 to the line 12. The plunger 5, with its screw thread 6 drives the screw 7 with the plunger 9. In this case, the volumes of the chambers “B” and “C” increase. With an increase in the volume of chamber "B", the process of suction of the working fluid into this chamber through valve 14 is in progress. With an increase in the volume of chamber "C", the process of suction of the working fluid into this chamber through valve 15 is in progress.

The plunger 5 closes with the screw 2, thereby forming a rotational link (screw - plunger). The rotation of the plunger 5 is converted into the translational components of the screw 7 with the plunger 9, the camera "C" increases, respectively, the suction occurs, the camera "B" decreases, respectively, the injection occurs. The volume of chamber “A” will not change.

At the end of the stroke of the screw 7, the plunger 5 and the screw 7 will be closed with each other and together with the plunger 9 will receive the translational component of the movement, as a result of which the volume of the chamber "A" will increase, accordingly, the process of absorption into this chamber, the volume of the chamber "C" will decrease, respectively, there will be a pumping process from this chamber. The volume of chamber "B" will remain unchanged.

Moving the plunger 5 and the screw 7 will lead to the closure of the screw 7 on the housing 3. Screw 7, having closed on the housing 3, becomes a rack. With the rotation of the screw 2, the translational component of the screw movement of the plunger 5 will lead to an increase in the volume of the chamber "B" and a decrease in the volume of the chamber "A". The volume of the camera "C" will not change. Further cycles are repeated.

Claims (10)

1. A plunger assembly, characterized in that it comprises a motor kinematically connected to a screw drive of the plunger pump, wherein the plunger pump comprises a housing with suction and pressure valves, inside of which two double-sided, relative to the relative to the axis of the housing move, rotationally mounted a plunger connected between itself and the housing, as well as with the motor shaft, a screw drive formed and representing installed with the possibility of rotational movement in the main link is a screw having an angle of inclination α _{1 of the} helical line, connected by the formation of a kinematic screw pair with a driven link - a double-sided plunger, through a screw-threaded hole with an angle of inclination α _{1 of a} helical line made in the center of its bottom, while this double-sided plunger , in addition to screw thread with an angle of inclination α _{1 of the} helix in the center of its opposite bottom, has a hole with screw thread with an angle of inclination α _{2 of the} helix, which it is associated with the formation of a helical kinematic pair with an output link - a screw, on the free end of which another double-sided plunger is installed, the output link - a screw has, in addition to screw thread with an angle of inclination α _{2 of the} helical line, a screw thread with an angle of inclination α _{3 of the} helical line, through which it is connected with the formation of a helical kinematic pairs with the body, while all screw threads of the same direction for helix lines are tilt angles: α ₃ <α ₁ <α ₂ , and the linear dimensions of the screw threads are interdependent on the movements of the links. 2. The plunger assembly according to claim 1, characterized in that the screw drive of the plunger pump is a ball screw. 3. The plunger assembly according to claim 1, characterized in that in the plunger pump, angular contact bearing provides support and fixation of the drive shaft of the screw drive. 4. The plunger assembly according to claim 1, characterized in that the cylindrical groove in the plunger pump body has height in sections made with smaller diameters, with each smaller diameter section of the cylindrical groove made within the stroke of the plunger and in height not exceeding dimensions the largest solids in a pumped plunger environment. 5. The plunger assembly according to claim 1, characterized in that the housing of the plunger pump is cylindrical. 6. The plunger assembly according to claim 1, characterized in that the plungers of the plunger pump are sealed. 7. The plunger assembly according to claim 1, characterized in that the channels for supplying fluid to the seals of the plungers are made in the plunger pump housing. 8. The plunger assembly according to claim 1, characterized in that the plunger pump housing is made of steel. 9. The plunger assembly according to claim 1, characterized in that the plungers of the plunger pump are made of bronze. 10. The plunger assembly according to claim 1, characterized in that the engine is electric.

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