CN111212977A

CN111212977A - Double-disc rotary cylinder type pump

Info

Publication number: CN111212977A
Application number: CN201880066906.XA
Authority: CN
Inventors: J·曲卡德; J·特罗斯特; P·帕格尼尔
Original assignee: IFP Energies Nouvelles IFPEN
Current assignee: IFP Energies Nouvelles IFPEN
Priority date: 2017-10-20
Filing date: 2018-10-08
Publication date: 2020-05-29
Also published as: CA3078594A1; FR3072735A1; WO2019076671A1; US20210164456A1; EP3698045A1

Abstract

The invention relates to a rotary barrel pump (6) comprising two discs: a movable disc (2), which is also driven by the drive shaft (5), and a disc (7) with a variable inclination, wherein the two discs (2, 7) are connected to each other such that they can pivot.

Description

Double-disc rotary cylinder type pump

Technical Field

The present invention relates to the field of pumps, in particular pumps for high-pressure pumping, in particular pumps for drilling operations.

Background

Currently, crankshaft-driven pumps are the most widely used in all industrial sectors: production data, oil, gas and food industry, automotive industry, construction industry (heating, wells, air conditioning, water pumps, etc.), and more specifically for water and waste treatment (water networks and drainage systems). However, they were still manufactured based on 1930's design and very little research and development research has been conducted to improve their performance, reduce their cost price, minimize their maintenance cost, or reduce their impact on the environment. These pumps have limitations in power, pressure/flow rate torque (i.e., limitations due to pressure surge-type phenomena caused by the sinusoidal response of the pressure generated by the crankshaft), weight, efficiency, and service life. Furthermore, they do not allow for variable displacement and therefore they lack flexibility in use.

Furthermore, in the field of hydrocarbon production, it is currently observed that wellbores need to reach greater and greater depths, which involve working at higher and higher injection pressures. Oil companies therefore require ultra high pressure pumps, for example for drilling mud injection, to achieve the required depth. These pumps must also be reliable, economical, flexible and compact in order to meet the increasingly stringent requirements of the energy sector.

Another positive displacement pump technology is the cartridge pump. It is mainly used for pumping at lower pressures and flow rates (it is mainly used for pumping hydraulic oil) and it has many advantages:

excellent weight/power ratio

Very good performance/price ratio

Advantageous mechanical and volumetric efficiency

-variable displacement capability by adjusting the inclination of the disc.

The pump designed with a cartridge operates by means of a rotating disc system which actuates the individual pistons one after the other. When one piston is in the intake phase, the opposite piston is in the delivery mode, which provides a constant flow upstream and downstream of the pump. The distribution of piston positions guided by the cartridge provides a progressive distribution of forces as the shaft driven by the motor rotates.

There are three main cartridge pump configurations:

fixed cartridge pump (fig. 1): in this configuration of the pump 1, with the cylinder fixed, it is the swashplate 2 (driven by the shaft 5) that rotates, generating the movement of the pistons 3 in their sleeves 4 (compression chambers). The coupling between the piston 3 and the disc 2 is then achieved by a ball joint pad rubbing on the disc 2. The advantage here is that the inertia of the rotating parts is very small. However, this configuration makes it difficult to have a variable displacement. Furthermore, at high pressures and high flow rates, the friction between the disc and the pad is not negligible and makes it difficult or even impossible to manufacture the pump;

oscillating disc-cartridge pumps: in this configuration, the drum is stationary and there are two discs, the first tilting disc rotating and only transmitting the oscillating motion to the second disc. Thus, each piston may be coupled to the second, oscillating disc without friction members, such as by a connecting rod coupled to the piston and to the disc by a ball joint. This structure is suitable for high pressure pumping (some of them can be found in the geothermal energy market) due to the absence of friction elements. It also provides excellent mechanical efficiency. This structure enables variable displacement to be produced, however it is still difficult to integrate and design;

rotating cartridge pump (fig. 2): within the pump 1, the disc 2 is fixed, while the cylinder 6 carrying the pistons 3 rotates, which provides the movement of the pistons 3 in their sleeves 4 (compression chambers). The coupling between the piston 3 and the disc 2 is arranged in the same way as in the first construction. This arrangement has the advantage that the disc can be easily adjusted in inclination, so that it can have a variable displacement. On the other hand, as the cylinder and all the pistons rotate, the inertia of the rotating parts increases in a significant manner. Furthermore, with this structure, significant friction occurs between the rod connected to the piston and the disc, which results in a loss of efficiency.

To overcome these drawbacks, the present invention relates to a rotary cartridge pump comprising two discs: a movable disk, also driven by a drive shaft, and a variable tilt reading disk, the two disks being coupled to each other by a pivotal connection. Thus, the movable disc driven by the drive shaft allows contact between the two rotating parts: a lever and a movable disk, thereby limiting frictional losses between these components. The variable inclination enables the displacement of the pump to be varied.

Disclosure of Invention

The present invention relates to a cartridge pump comprising a housing and, within said housing:

-a drive shaft,

a cylinder comprising at least two circumferentially distributed compression chambers, the cylinder being driven by the drive shaft,

-a movable plate which is movable relative to the frame,

-at least two pistons, each translating in the compression chamber of the cylinder, the pistons being driven by the movable disc by means of a connecting rod,

the movable disc is driven by the drive shaft, and the cartridge pump includes a disc having a variable inclination relative to the drive shaft, the movable disc being pivotally connected relative to the variable inclination disc about an axis of the variable inclination dial.

According to one embodiment of the invention, said pivotal connection between said movable disc and said variable-inclination dial comprises means for supporting a load and means for supporting the assembly of the two discs.

Advantageously, said pivotal connection between said movable disc and said variable-inclination dial is constituted by a tapered roller thrust bearing and a ball bearing.

Preferably, the tapered roller thrust bearing is disposed between an outer shoulder of the movable disk and an inner shoulder of the variable inclination disk.

Advantageously, the ball bearing is arranged between an outer shoulder of the movable disc and an inner shoulder of the variable inclination dial.

According to one embodiment, the movable disc is driven by the drive shaft through a pin ball joint.

According to one aspect, the pin ball joint comprises means for forming the pin ball joint in the form of a hollow swivel part comprising a substantially cylindrical inner surface and an outer surface having a substantially truncated spherical shape at both ends, the inner surface comprising at least one groove or one internal spline (female ) and the outer surface comprising at least one crowned spline.

Advantageously, the means for forming a pin ball joint are mounted on the drive shaft by means of a key or splined shaft, and the movable disc is mounted on said means by means of at least one groove cooperating with said at least one crowned (or dome-shaped) spline.

Preferably, the movable plate comprises a part spherical inner surface.

According to an embodiment of the invention, the cartridge pump comprises means for controlling the inclination of the variable inclination dial.

Advantageously, said inclination control means comprise a worm drive system.

Preferably, the lever is connected to the movable disk without a friction pad.

Furthermore, the invention relates to the use of a cartridge pump according to one of the above-mentioned features in drilling operations, in particular for injecting drilling mud into a borehole.

Drawings

Further characteristics and advantages of the device according to the invention will become apparent from reading the following description of an embodiment, given by way of non-limiting example, with reference to the accompanying drawings, in which:

FIG. 1, already described, shows a fixed cartridge pump according to the prior art,

FIG. 2, already described, shows a rotary cartridge pump according to the prior art,

figure 3 shows a cartridge pump according to an embodiment of the invention,

figure 4 shows a device for forming the pin ball joint coupling required for the rotation and tilting of the movable disc, according to an embodiment of the invention, an

Figure 5 shows the pivotal connection between the movable disc and the variable inclination dial according to an embodiment of the present invention.

Detailed Description

The present invention relates to a rotary barrel pump. The purpose of a cartridge pump is to pump fluid (e.g., water, oil, gas, drilling mud, etc.) through the linear displacement of several pistons. This type of pump has the advantages of being compact, having advantageous mechanical and volumetric efficiencies, and excellent weight/power ratio. Furthermore, rotary barrel pumps are suitable for high pressure pumping.

A cartridge pump according to the present invention includes a housing, and it includes within the housing:

a drive shaft which is driven in rotation relative to the housing by an external energy source, in particular a prime mover (e.g. a thermal or electrical prime mover), in particular by means of a transmission (e.g. a gearbox),

a movable (rotating) disc driven by a drive shaft: the movable disc is driven relative to the drive shaft, whereby the disc rotates, and, in addition, the movable disc rotates relative to the drive shaft,

the cylinder (called barrel) comprises at least two compression chambers (also called sleeves) distributed circumferentially (in other words arranged on a circle), the cylinder being rotary and driven by the drive shaft,

at least two pistons, each translating in a compression chamber, the pistons being driven by a movable disc by means of a connecting rod (the rod connecting the movable disc and the piston by means of a spherical joint, thereby converting the movement of the movable disc into a translational movement of the piston), and the translation of the pistons in the compression chambers generating a pumping of the fluid, and

in addition to adjusting the inclination of the drive shaft, a disk with a variable inclination with respect to the drive shaft, which is fixed with respect to the housing, and the movable disk is pivotally connected with respect to the variable inclination dial about an axis of the variable inclination dial (which axis corresponds to the normal direction of the disk and can correspond to the swivel axis of the variable inclination dial when the disk has the shape of a circular disk), so that the inclination of the movable disk is the same as the inclination of the variable inclination dial.

The variable inclination of the variable inclination dial allows the pump to have a variable displacement by varying the stroke of the piston.

Advantageously, the ball joint between the connecting rod and the movable disk is provided without friction pads (no friction connection between the rod and the movable disk), which is possible by means of the movable disk. In fact, one of the specific features of the present invention is based on a dual disc design, and more particularly on the connection of the movable disc to the variable inclination disc and its driving via the power input shaft. Most disc pumps exist on the market for lower flow rates and pressure activity and therefore the mechanical stress on the individual pump components is more limited. In the context of the high flow rates and high pressure use of these pumps available on the market, the mechanical stresses involved are significant, and therefore friction pads are necessary for these pumps. Furthermore, in addition to reducing the final efficiency of the pump by several points, the design of the friction pads between the rod and the swash plate becomes critical. Thus, the dual disk design, with one disk fixed and the other rotating, allows the final efficiency of the pump to be increased without friction pads and enables the pump to be used at high flow rates and high pressure conditions.

According to an embodiment of the invention, the pivotal connection between the movable disc and the variable tilt dial may consist of means for supporting the load and means for supporting the assembly of the two discs. For example, the pivotal connection can be made up of a tapered roller thrust bearing and a ball bearing. The tapered roller thrust bearing is capable of bearing both axial and radial loads exerted on each disc, while the ball bearing allows for support of the assembly of the two discs (the movable disc and the variable tilt dial).

According to an aspect of this embodiment, the movable disk may comprise two outer shoulders for the arrangement of the tapered roller thrust bearing and the ball bearing. A shoulder with a smaller diameter may be used to receive the tapered roller thrust bearing and it may be provided on the side of the movable disc remote from the connecting rod. Furthermore, a shoulder having a larger diameter may be used to receive the ball bearing, and it may be disposed near a side of the movable disk near the lever.

Further, the variable tilt dial may include two internal shoulders for the arrangement of the tapered roller thrust bearing and the ball bearing. A shoulder having a smaller diameter may be used to receive the tapered roller thrust bearing and it may be disposed near the center of the variable tilt dial. Further, a shoulder having a larger diameter may be used to receive the ball bearing, and it may be provided on a side of the variable tilt dial close to the movable disk.

This arrangement of the tapered roller thrust bearing and the ball bearing with an inner shoulder and an outer shoulder provides for a simple assembly of the two discs.

According to one embodiment of the invention, the movable disk may be driven by the drive shaft via a pin ball joint. A pin ball joint is a coupling between two mechanical elements, which has four degrees of coupling (degredde liaison) and two degrees of relative movement (degredde movement relationship); only two relative rotations are possible, three translations and the last rotation being coupled. Typically, it is a ball joint provided with an anti-rotation pin. The working principle of this type of coupling consists in providing a torque transmission between two rotating assemblies whose axes are not collinear.

The pin ball joint allows the rotation of the movable disc and the cylinder (barrel) to be synchronized.

According to an aspect of this embodiment of the present invention, the pin ball joint may be composed of a specific means for forming the pin ball joint. The means for forming the pin ball joint may be a hollow swivel portion. It should be noted that in geometry, a turnaround portion is a portion that results from rotation of a closed planar surface about an axis that lies in the same plane, the axis having no point in common with, or only a boundary point with, the closed planar surface.

For clarity of description, the term "device" is used in the rest of the description below to denote a specific device for forming a pin ball joint.

The means for forming the pin ball joint includes a generally cylindrical inner surface. Thus, the hollow portion of the device is substantially cylindrical. Thus, the device is adapted to be mounted on a cylindrical shaft. The inner surface includes at least one groove for inserting a key or at least one internal spline for inserting a spline shaft, thereby transmitting torque between the shaft and the device. High torque transmission can be achieved using a keyed or splined transmission.

The device according to the invention comprises an outer surface which has substantially the shape of a truncated sphere at both ends. The sphere is truncated by two planes perpendicular to the axis of rotation of the device. This part-spherical shape of the outer surface provides a spherical joint. Further, the outer surface includes at least one crowned (or dome-shaped) spline. Crowned splines allow, on the one hand, the pin forming the pin ball joint and, on the other hand, provide a large torque transmission between the device and an element (e.g. a disc or disk) located between the outer surface of the device.

This design of the means for forming the pin ball joint provides high compactness, large angular displacement and ease of use.

Advantageously, the groove(s) and the spline(s) are parallel to the axis of revolution of the device.

Preferably, the spline(s) of the outer surface have a crowned (or dome-like) shape parallel to the overall spherical shape of the outer surface of the device. Thus, each spline may be an involute spline (a spline that spreads along a circle) so as to have the maximum transmittable torque.

According to an aspect of this embodiment of the invention, the outer surface comprises a plurality of crowned splines evenly distributed on the circumference of the spherical surface. Thus, higher torques can be transmitted between the device according to the invention and the element located on the outer surface of the device. The splines are preferably parallel to each other. For example, the outer surface of the device may comprise five to nineteen, preferably seven to thirteen, crowned splines in order to optimise the manufacture of the device and the torque transmittable thereby, and to optimise the distribution of forces in the splines.

Thus, for a pin ball joint coupling between the drive shaft and the movable disc, the means for forming the pin ball joint is mounted on the drive shaft by means of at least one key or by means of a splined shaft. Furthermore, a movable disc is mounted on the outer surface of the device, forming a pin ball joint coupling by means of at least one crowned groove (internal spline) cooperating with the crowned spline(s).

With the invention, a pin ball joint coupling is formed between the drive shaft and the movable disk: the movable disc is rotatable by means of a spherical outer surface of the device and torque can be transmitted to the disc by means of a key or by splines of the drive shaft or by means of crown spline(s).

Here, the coupling is a non-slip constant velocity spherical joint, which means that the rotational speed at the joint input is the same as the rotational speed at the joint output, and the connection takes place without slip by direct mechanical drive.

Such a connection may enable a pin ball joint connection, providing high compactness, large angular displacement, and ease of use.

To achieve a pin ball joint coupling, the movable disc may comprise a substantially spherical inner surface provided with internal splines.

To facilitate the assembly of the connection, the movable disc may be composed of two half-shells. Alternatively, the movable disc may be made in one piece.

According to an aspect of the invention, the movable disc may comprise means forming an angle stop. It may be a surface in contact with the shaft; for example, the disc may include a tapered inner surface that contacts the shaft for maximum angular displacement.

As an alternative to this embodiment of the pin ball joint, the ball joint coupling may be a ball joint bearing.

The disc may have the general shape of a circular disc. However, the disc may have any shape. Except that the compression chambers (and pistons) are arranged circumferentially.

Advantageously, the pump according to the invention may comprise a number of pistons ranging between three and fifteen, preferably between five and eleven. Thus, the large number of pistons provides a continuous flow upstream and downstream of the pump.

Typically, the pump also comprises an inlet and an outlet for the fluid to be pumped. Fluid flows through the pump inlet, into the compression chamber, is compressed in the compression chamber, and then it is discharged from the pump through the outlet by means of the piston.

According to an embodiment of the present invention, the inclination angle of the variable inclination dial with respect to the axial direction of the drive shaft may be in a range between 70 ° and 90 °. In other words, the variable inclination dial (let alone the rotary disk) may be inclined at an angle ranging between 0 ° and 20 ° with respect to the radial direction of the drive shaft.

According to an embodiment of the present invention, the cartridge pump may include means for controlling the inclination of the variable inclination dial. For example, the control means may comprise a worm drive system.

According to an aspect of the invention, the cartridge may be made of two parts, a first part for guiding and a second part for sealing.

By way of non-limiting example, FIG. 3 schematically illustrates a motion diagram of a rotary barrel pump according to an embodiment of the present invention. The rotary cartridge pump 1 comprises a drive shaft 5. Rotation of the drive shaft 5 is performed by an external source (not shown), such as a motor and gearbox. The drive shaft 5 rotates relative to the housing 15. Further, the drive shaft 5 rotationally drives a cylinder 6 including the compression chamber 4.

The drive shaft 5 also drives the movable disc 2 by means of a pin ball joint 9.

The pump 1 further comprises a variable inclination dial 7, which variable inclination dial 7 is fixed relative to the housing 15, in addition to the adjustment of its inclination. A means for adjusting the inclination of the variable inclination dial 7 is not shown.

The movable disk 2 is pivotally connected relative to the variable tilt dial 7 about the axis of the variable tilt dial 7.

The pump 1 comprises a piston 3 driven in translational movement (reciprocating movement) in a compression chamber 4.

The reciprocating movement of the piston 3 is effected by means of a rod 8, the rod 8 connecting the wobble plate 2 and the piston 3 by means of a ball joint. This reciprocating movement of the piston 3 within the compression chamber 4 allows pumping of fluid.

By way of non-limiting example, fig. 4 schematically illustrates an apparatus for forming a pin ball joint coupling according to an embodiment of the present invention. The device 10 is a revolving portion rotating about the axis XX. The device 10 is hollow and it comprises a cylindrical inner surface 11. The inner surface 11 comprises a groove 14. The cross-section of the groove 14 is substantially rectangular. The device 10 comprises an outer surface 12, which outer surface 12 has, on both ends, a substantially truncated spherical shape, the truncation being effected on two planes perpendicular to the axis XX. The outer surface 12 includes a plurality of crowned (or dome-shaped) splines 13, in the illustrated case nine crowned splines 13. The crowned splines 13 have an outer surface that is generally parallel to the outer surface 12 of the device. These splines 13 are involute splines.

By way of non-limiting example, FIG. 5 schematically illustrates a pivotal connection between two discs (a movable disc and a variable tilt dial). Fig. 5 is a sectional view along a plane including the axis of the drive shaft 5. The figure shows the variable tilt dial 7, the movable dial 2 and the connecting rod 8. The rod 8 is connected in the movable plate 2 with a ball joint without friction pads.

The axis YY is the axis of the variable inclination dial 7. The movable plate 2 is pivotally connected to the variable tilt dial 7 about the tilt axis YY of the variable tilt dial 7. Therefore, the inclination of the movable disk 2 is the same as that of the variable inclination dial 7. The pivotal connection includes a tapered roller thrust bearing 16 and a ball bearing 18.

The movable disk 2 comprises two

outer shoulders

20 and 22 for the arrangement of the conical roller thrust bearing 16 and the ball bearing 18. A shoulder 20 with a smaller diameter is provided for receiving the conical roller thrust bearing 16 and is arranged on the side of the movable disc 2 remote from the lever 8. Furthermore, a shoulder 22 with a larger diameter is provided for receiving the ball bearing 18 and is arranged near the side of the movable plate 2 close to the rod 8.

Furthermore, the variable inclination dial 7 includes two

inner shoulders

19 and 21 for providing the tapered roller thrust bearing 16 and the ball bearing 18. A shoulder 19 having a smaller diameter is provided for receiving the tapered roller thrust bearing 16 and is disposed near the center of the variable inclination dial 7. Further, a shoulder portion 21 having a larger diameter is provided for receiving the ball bearing 18, and is provided on the side of the variable inclination dial 7 close to the movable disk 2.

Fig. 5 further illustrates an apparatus for forming the pin ball joint 10. The device 10 corresponds to the device for forming a pin ball joint shown in fig. 4. The device 10 is mounted on the drive shaft 5 by means of a key 17.

The invention also relates to the use of the pump according to the invention for drilling operations, in particular for cementing drilling mud into a wellbore. In fact, the pump according to the invention is very suitable for this purpose because of its flexibility, compactness and high pressure resistance.

For example, the pump according to the invention may be dimensioned up to 1500 bar (bar), i.e. 15 barOperating at a pressure of the order of 0 MPa. Furthermore, the pump according to the invention may be dimensioned in the range of 30 to 600m³Flow rate operation in/h.

Claims

1. A cartridge pump comprising a housing (15) and, within the housing (15):

-a drive shaft (5),

-a cylinder (6) comprising at least two compression chambers (4) distributed circumferentially, the cylinder (6) being driven by the drive shaft (5),

-a movable disc (2),

-at least two pistons (3) that respectively translate in said compression chambers (4) of said cylinders (6), said pistons (3) being driven by said movable disc (2) by means of a connecting rod (8),

characterized in that said movable disc (2) is driven by said drive shaft (5) and in that said cartridge pump (1) comprises a disc (7) having a variable inclination with respect to said drive shaft (5), said movable disc (2) being pivotally connected with respect to said variable inclination disc (7) about an axis (YY) of said variable inclination disc (7).

2. A pump according to claim 1, wherein the pivotal connection between the movable disc (2) and the variable inclination dial (7) comprises means for supporting a load and means for supporting the assembly of the two discs.

3. Pump according to claim 2, characterized in that said pivotal connection between said movable disc (2) and said variable-inclination dial (7) comprises a tapered roller thrust bearing (16) and a ball bearing (18)

4. A pump according to claim 3, wherein the tapered roller thrust bearing (16) is provided between an outer shoulder (20) of the movable disc (2) and an inner shoulder (19) of the variable-inclination disc (7).

5. Pump according to any one of claims 3 or 4, characterized in that the ball bearing (18) is arranged between an outer shoulder (22) of the movable disk (2) and an inner shoulder (21) of the variable-inclination dial (7).

6. Pump according to any one of the preceding claims, characterized in that the movable disc (2) is driven by the drive shaft (5) through a pin ball joint (9).

7. Pump according to claim 6, characterized in that the pin ball joint (9) comprises means (10) for forming the pin ball joint in the form of a hollow revolution comprising a substantially cylindrical inner surface (11) and an outer surface (12) having substantially a truncated spherical shape at both ends, the inner surface (11) comprising at least one groove (14) or one internal spline and the outer surface (12) comprising at least one crowned spline (13).

8. Pump according to claim 7, characterized in that the means (10) for forming a spherical joint are mounted on the drive shaft (5) by means of a key (17) or a splined shaft, and in that the movable disc (2) is mounted on the means (10) by means of at least one groove cooperating with the at least one crowned spline (13).

9. A pump according to any of claims 6 or 7, wherein the movable disc (2) comprises a part-spherical inner surface.

10. A pump according to any preceding claim, wherein the cartridge pump (1) comprises means for controlling the inclination of the variable inclination dial.

11. A pump according to claim 10, wherein the inclination control means comprises a worm drive system.

12. Pump according to any one of the preceding claims, characterized in that the rod (8) is connected to the movable disc (2) without friction pads.

13. Use of a cartridge pump (1) according to any of the preceding claims in drilling operations, in particular for injecting drilling mud into a wellbore.