Pump as well as a recirculation device for a pump

Abstract

Disclosed is a pump for conveying a pump having a pump rotor rotatably supported about an axis of rotation in a pump stator in the operating state and a rotor shaft is arranged in a shaft leadthrough such that a lubricating film of a lubricating fluid formed from the pump fluid can be formed in a ring gap between the rotor shaft and the shaft leadthrough; and wherein a separation device is provided at the rotor shaft by which a predefinable quantity of an ingredient can be separated from the pump fluid by means of a centrifugal force for providing the lubricating fluid at the ring gap in the operating state, wherein a recirculation device is provided so that a gas can be recirculated with the aid of the separation device.

Claims

1. A pump for conveying a pump fluid in the form of a multiphase mixture, wherein the pump fluid provided at an input pressure at a low-pressure side of the pump can be conveyed to a high-pressure side of the pump by means of a pump rotor rotatably supported about an axis of rotation in a pump stator in the operating state and a rotor shaft is arranged in a shaft leadthrough such that a lubricating film of a lubricating fluid formed from the pump fluid can be formed in a ring gap between the rotor shaft and the shaft leadthrough; and wherein a separation device is provided at the rotor shaft by which a predefinable quantity of an ingredient can be separated from the pump fluid by means of a centrifugal force for providing the lubricating fluid at the ring gap in the operating state, wherein a recirculation device is provided which separates a gas from the pump fluid in the separation device and recirculates the separated gas to the high-pressure side of the pump with the aid of the separation device.

2. A pump in accordance with claim 1, wherein the shaft leadthrough forms a shaft bearing and a stationary bushing includes a rotating shaft sleeve.

3. A pump in accordance with claim 1, wherein the shaft leadthrough forms a constriction point.

4. A pump in accordance with claim 1, wherein the ring gap can be formed between the stationary bushing and the rotating shaft sleeve.

5. A pump in accordance with claim 1, wherein the recirculation device includes a feed line, a recirculation line and a means to increase pressure, in particular a conveying screw and/or a grooved line.

6. A pump in accordance with claim 5, wherein the recirculation device is flow-connected to the high-pressure side of the pump by means of the feed line for supplying the pump fluid so that the pump fluid flows from the high-pressure side of the pump to the recirculation device in the operating state.

7. A pump in accordance with claim 5, wherein the separation device includes a first separation opening for separating the gas and/or a second separation opening for separating an ingredient and/or a third separation opening for separating the lubricating fluid.

8. A pump in accordance with claim 7, wherein the first separation opening for separating the gas is flow-connected to the recirculation device, specifically to the recirculation line.

9. A pump in accordance with claim 7, wherein the separation device includes the second and third separation openings, and wherein the second separation opening is flow-connected to the low-pressure side of the pump by means of a separation line for leading off the ingredient and/or the ring gap is flow-connected to the third separation opening of the separation device by means of a lubricant opening such that lubricating fluid at least partly liberated from the ingredient can be supplied to the ring gap via the lubricant opening for lubricating the shaft leadthrough.

10. A pump in accordance with claim 5, wherein the recirculation device is flow-connected to the high-pressure side of the pump and/or to a gas sink by means of the recirculation line for recirculating the gas.

11. A pump in accordance with claim 10, wherein the recirculation line is designed such that a pressure in the recirculation line is higher than on the high-pressure side of the pump and/or of the gas sink by means of the means to increase pressure and the gas can be conveyed by the recirculation device to the high-pressure side of the pump and/or to the gas sink.

12. A pump in accordance with claim 1, wherein the separation device co-rotates with the rotor shaft about the axis of rotation and includes a ring chamber, at which ring chamber a separation opening is provided, which is preferably aligned tangentially, for separating the ingredient.

13. A pump in accordance with claim 1, wherein the recirculation device is formed as an integral component in the pump stator.

14. A pump in accordance with claim 1, wherein a lubricant line is provided such that a predefinable quantity of lubricating fluid can be led off from the separation device, in particular for feeding a further lubricating point of the pump.

15. A recirculation device for a pump in accordance with claim 1.

Description

(1) The invention will be explained in more detail in the following with reference to the drawing. There are shown in a schematic representation:

(2) FIG. 1 the prior art for the example of a pump with a separation disk;

(3) FIG. 2 an embodiment of a pump in accordance with the invention with a recirculation device; and

(4) FIG. 3 a detailed representation of an embodiment of a pump in accordance with the invention with a recirculation device.

(5) It applies to the following description of the Figures that all the reference numerals which refer in the examples to the features of the prior art are provided with a dash and all the reference numerals which refer to embodiments in accordance with the invention are not marked by a dash.

(6) FIG. 1 shows the prior art with reference to a pump, with the design of the shaft leadthrough with a separation device being shown somewhat more exactly in detail. The pump, which is designated by the reference numeral 1 as a whole in the following serves very generally for the conveying of a pump fluid 2 in the form of a multiphase mixture, i.e. the multiphase mixture is composed of different solid, liquid and gaseous ingredients. The ingredients are substantially sand and gas which are present in the pump fluid 2 as pollutants in non-tolerable quantities. The pump fluid 2 is crude oil here which is available at a low-pressure side LP' of the pump 1 at an inlet pressure and which is conveyed to a high-pressure side HP of the pump 1 by means of a pump rotor (not shown) rotatably about an axis of rotation A in accordance with the arrow P supported in a pump stator (not shown) in the operating state. The pump rotor is in this respect designed and is arranged above a rotor shaft 5 in a shaft leadthrough 6 such that a lubricating film of a lubricating fluid 200 formed from the pump fluid 2 can be formed in a lubricating ring gap 21 between the rotor shaft 5 and the shaft leadthrough 6. It can additionally be seen that a separation device 7 is provided at the rotor shaft 5 by which a predefinable quantity of the ingredient can be separated from the pump fluid 2 by means of a centrifugal force in the operating state for providing the lubricating fluid 200.

(7) As shown schematically in FIG. 1, the separation device 7, which is here designed as a separation disk screwed to the rotor shaft 5 of the pump 1 by screws 70, is connected to the high-pressure side HP of the pump 1 via a feed line for supplying the pump fluid 2, that is here the crude oil, including the ingredient. The separation disk is in this respect covered by a cover D through which the pump fluid 2 is supplied to the separation disk.

(8) As shown in detail in FIG. 1, the separation disk co-rotating with the rotor shaft 5 about the axis of rotation A includes a ring chamber, with at least one substantially tangentially aligned separation opening being provided at the ring chamber for separating the ingredients. The separation opening is connected via a separation line 721 to the low-pressure side LP' of the pump 1 for leading off the separated ingredient, that is in the present example for leading off the sand deposited in the crude oil. In this respect, the sand has a higher density than the lubricating fluid 200 which is finally used for lubricating the rotor shaft 5.

(9) So that the lubricating fluid 200 can be provided for lubricating the rotor shaft 5 in the shaft leadthrough 6, the lubricating ring gap 21 is flow-connected to the separation device 7 by means of a lubricant opening 22 such that the lubricating fluid 200 at least partly liberated from sand can be supplied to the ring gap 21 via the lubricant opening 22 for lubricating the shaft leadthrough 6.

(10) A lubricant line 10 is furthermore additionally provided such that a predefinable quantity of lubricating fluid 200 can be led off by the separation disk, in particular for feeding a further lubricating point of the pump 1, which additional lubricating points are not explicitly shown for reasons of clarity. In this respect, the lubricating fluid 200 branched off via the lubricant line 10 is used for lubricating further plant parts which are disposed outside the pump 1 or which are not part of the pump 1.

(11) As already mentioned, the separation device 7, that is here the separation disk, is releasably connected to the rotor shaft 5; however, it is also possible that the separation device 7 is an integral component of the rotor shaft 5 and the separation device 7 is in particular a separation disk integrally connected to the rotor shaft 5.

(12) The pump in accordance with the invention serves very generally, and in particular in the specific embodiment of FIG. 2 and FIG. 3, for the conveying of a pump fluid in the form of a multiphase mixture. The pump, which is designated by the reference numeral 1 as a whole in the following serves very generally for the conveying of a pump fluid 2 in the form of a multiphase mixture, i.e. the pump fluid is composed of different solid, liquid and gaseous ingredients. The ingredients are substantially sand and gas which are present in the pump fluid 2 as pollutants in non-tolerable quantities. The pump fluid 2, for example crude oil, which is available at an input pressure at a low-pressure side LP of the pump 1 and which can be conveyed to a high-pressure side HP of the pump by means of a pump rotor 4 rotatably supported about an axis of rotation A in accordance with the arrow P in a pump stator 3 in the operating state and a rotor shaft 5 is arranged in a shaft leadthrough 6 such that a lubricating film of a lubricating fluid 200 formed from the pump fluid 2 can be formed in a ring gap 21 between the rotor shaft 5 and the shaft leadthrough 6. In addition, a separation device 7 is provided at the rotor shaft 5 by which a predefinable quantity of an ingredient can be separated from the pump fluid 2 by means of a centrifugal force in the operating state for providing the lubricating fluid 200 at the ring gap 21. In accordance with the invention, a recirculation device 8 is provided so that a gas 201 can be recirculated with the aid of the separation device 7.

(13) As shown schematically in FIG. 2, the shaft leadthrough 6 includes a stationary bushing 9 and a rotating shaft sleeve 10. The ring gap 21 can in this respect, as in the present embodiment, be formed both between the stationary bushing 9 and the rotating shaft sleeve 10 and directly between the rotor shaft 5 and the shaft leadthrough 6.

(14) In addition, the recirculation device 8 shown in FIG. 2 includes a feed line 81, a recirculation line 82 and a means to increase pressure 83, in particular a screw conveyor and/or a grooved line. The recirculation device 8 is flow-connected to the high-pressure side HP of the pump by means of the feed line 81 for supplying the pump fluid 2 so that the pump fluid 2 flows from the high-pressure side HP of the pump to the recirculation device 8.

(15) The separation device 7 and/or the separation disk co-rotating with the rotor shaft 5 about the axis of rotation A in detail includes a ring chamber, at which ring chamber a preferably tangentially aligned separation opening is provided for separating the ingredient. In the present embodiment, which is particularly preferred, the separation device 7 or the separation disk includes a first separation opening 71 for separating the gas 201 and/or a second separation opening 72 for separating an ingredient and/or a third separation opening 73 for separating the lubricating fluid.

(16) So that the separated gas 201 is separated into the recirculation device 8 and/or into the recirculation line 82, the first separation opening 71 for separating the gas 201 is flow-connected to the recirculation device 8 and/or to the recirculation line 82. For recirculating the gas 201, the recirculation device 8 is flow-connected to the high-pressure side HP of the pump and/or to a gas sink by means of the recirculation line 82. The means to increase pressure 83 are in this respect required to generate a pressure in the recirculation line 82 which is higher than on the high-pressure side HP of the pump and/or of the gas sink so that the gas 201 can be conveyed by the recirculation device 8 to the high-pressure side HP of the pump and/or to the gas sink. As already mentioned, the recirculation device 8 is formed as an integral part in the pump stator 3; however, it is also possible that the recirculation device 8 is an external recirculation device 8 releasably connected to the pump.

(17) So that the lubricating fluid 200 can be provided for lubrication, the ring gap 21 is flow-connected to the third separation opening 73 of the separation device 7 by means of a lubricant opening 22 such that the lubricating fluid 200 at least partly liberated of the ingredient can be supplied to the ring gap 21 via the lubricant opening 22 for lubricating the shaft leadthrough 6.

(18) A lubricant line is furthermore additionally provided such that a predefinable quantity of lubricating fluid 200 can be led off by the separation disk, in particular for feeding further lubricating points of the pump 1 which additional lubricating points are not explicitly shown for reasons of clarity. In this respect, the lubricating fluid 200 branched off via the lubricant line is used for lubricating further plant parts which are disposed outside the pump 1 or which are not part of the pump 1.

(19) The second separation opening 72 is connected via a separation line 721 to the low-pressure side LP of the pump 1 for leading off the separated ingredient, that is in the present example for leading off the sand deposited in the crude oil. In this respect, the sand has a higher density than the lubricating fluid 200 which is used for lubricating the rotor shaft 5.

(20) The separation line 721 is designed as an integral component in the shaft leadthrough 6 or in the pump stator 3, but can also be guided as a separate, additional separation line 721, for example at the outside of the housing of the pump.

(21) As an advantageous measure, a second constriction point 74 is provided which serves for the increase of the resistance to avoid a direct flowing off of the pump fluid 2.

(22) It is understood that all the embodiments of the invention shown only by way of example in the Figures are only to be understood as examples or by way of example and that the invention in particular, but not only, includes all suitable combinations of the described embodiments.