EP2626564A1 - Pump, separation device for a pump, and a rotor shaft for a pump - Google Patents

Abstract

The pump (1) has a pump rotor (4) rotatably supported around a rotational axis (A) in a pump stator (3) in an operating state, and a rotor shaft (5) arranged in a shaft feedthrough (6) such that a lubricating film of a lubricating fluid is formed in a ring gap between the shaft and the feedthrough. A separation device (7) is arranged at the shaft for separating a predefinable quantity of an ingredient from pump fluid (2) by centrifugal force for providing the lubricating fluid to the gap. A recirculation device (8) is arranged such that gas (201) is recirculated with the separation device. The separation device is designed as a separation disk.

Description

The invention relates to a pump for delivering a constituent pump fluid, a separation device, and a rotor shaft for a pump according to the preamble of the independent claims 1, 11, and 14.

In the prior art, it is a well-known measure to lubricate rotating parts of pumps with the medium to be pumped itself, which has the obvious advantage that then no special lubricant must be provided for these lubrication applications. This may be of particular advantage especially if the provision of the lubricant, for example for the lubrication of a rotary rotor shaft of the pump carrying a pump rotor, is possible only with particular difficulty. Another advantage is that it is possible to dispense with a shaft seal on the non-drive side through the use of a self-lubricating or product-lubricated bearing, since the shaft no longer has to be led out to the atmosphere. Prominent examples include a variety of other applications pumps for the promotion of multi-phase mixtures, such as to promote crude oil. Such pumps often need to be in very hard to reach places often hundreds of meters, even up to a few thousand meters below the sea surface, where the pumps must be operated reliably under extreme conditions for considerable periods of time.

It is understood that the pumps at such or other poorly accessible places should have as little maintenance and in particular as little as possible need for externally supplied supplies, such as to have special lubricating oil. As far as the necessary lubrication of such pumps is concerned, the use of the medium to be pumped as lubricant is the means of choice, since the medium to be pumped is of course already available in the pump, in practically any quantities, so that no lubricant has to be provided separately from the outside and the lubricant must not be replaced after a certain period of operation, because constantly fresh and unused lubricant from the pumped medium itself is available.

But also in other applications where the pumps are well accessible, for example, of course, the use of the medium to be pumped as a lubricant great advantages, just because no separate lubricant must be made available, which the pumps during operation more cost-effective and often in the apparatus design makes it easier. Also eliminates a large part of the maintenance related to the lubrication and the life, ie the maintenance intervals are extended because not least the regular replacement of the corresponding lubricant is no longer necessary.

However, a hitherto unsatisfactorily solved problem occurs in the promotion of such pumping media, such as in a multi-phase mixture containing not only crude oil but also natural gas and often water and especially harmful solid components such as sand. The additional In fact, ingredients are often harmful to lubrication. So the expert understands immediately that, for example, especially hard ingredients such as sand can affect the lubrication massive negative. For example, if a lubricant contaminated with sand is used to lubricate a rotor shaft of an impeller, the sand in the lubricant can cause considerable damage to the parts to be lubricated, because the hard sand grains damage the surfaces of the components to be lubricated, which are often made of relatively soft metal which can eventually lead to failure of the pump.

Therefore, it is known in the prior art, especially to harden such parts, which are lubricated with a sand contaminated lubricant, for example, so that the sand contained in the lubricant can not damage the surfaces, or at least as far as the wear of the corresponding parts reduce, that reasonably long service life, so economically reasonable maintenance intervals can be achieved.

In this case, the hardening of the corresponding parts, such as the rotor shaft of an impeller of the pump or the rotor shaft bearing form static or rotating counterpart and bearing components, of course, a measure that is on the one hand very complex and therefore expensive and ultimately does not solve the problem actually because even Hardened parts with time of rubbing load, for example by sand contained in the lubricant, can not withstand long term. Another point is that, for example, the width of the lubricant gaps between the rotating and / or static parts of the bearings often can not be reduced to the desirable level, because otherwise the harmful influence of hard, non-compressible ingredients such as sand would be so great that premature wear of the corresponding bearings would be inevitable. The fact that the bearing gaps are not optimally adjustable by such restrictions, the smoothness of the stored parts can be adversely affected, and by Not optimally adjusted lubricant gaps can cause harmful vibrations in the operating state, which can ultimately also lead to premature wear.

But not only solid ingredients but also liquid or gaseous ingredients can adversely affect the lubricating behavior, because, for example, the viscosity, ie the viscosity of the pump fluid used as a lubricant for use as a lubricant is poor or not at all suitable.

The object of the invention is therefore to propose a pump for pumping an ingredient comprising a pumping fluid, in which the medium to be pumped can be used simultaneously for lubricating rotating parts of the pump, in particular for lubricating the rotor shaft of the pump rotor, wherein the from the prior art known harmful influences of the ingredients are largely avoided on the lubrication process. Another object of the invention is to provide a separation device and a rotor shaft for such a pump.

The objects of the invention solving this object are characterized by the features of independent claims 1, 11, and 14.

The dependent claims relate to particularly advantageous embodiments of the invention.

The invention thus relates to a pump for pumping an ingredient comprising a pumping fluid, wherein in the operating state the pumping fluid provided at an inlet 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 mounted in a pump stator about a rotation axis. In this case, the pump rotor is configured and arranged via a rotor shaft in a shaft bearing that between the rotor shaft and the shaft bearing in a lubricating ring gap, a lubricating film can be formed from a lubricating fluid formed from the pumping fluid. According to the invention, a separation device is provided on the rotor shaft, with which a specifiable amount of the ingredient can be separated from the pumping fluid by means of a centrifugal force in the operating state for providing the lubricating fluid.

It is therefore essential for the invention that a separation device is provided on the rotor shaft, with which in the operating state a predeterminable amount of the ingredient, often sand in practice, can be separated from the pumping fluid by means of a centrifugal force. For this purpose, the pumping fluid to be pumped by the pump, for example, with sand loaded crude oil, which is conveyed from a raw source through the pump in a common storage, be promoted from the high pressure side of the pump into a chamber of the rotor axis co-rotating with the separation device at the end of the rotor axis , The pumping fluid is exposed in the rotating separation device to the centrifugal forces acting there due to the rotation and is conveyed to the outside, for example, into an outer annular chamber of the separation device. Due to the higher density of the sand compared to the liquid portion of the pumping fluid, the sand will accumulate under the centrifugal force at the outer edge of the annular chamber of the separator, so that form at the outer edge of the annular chamber, a sand highly enriched phase of the pumping fluid over a corresponding discharge opening is preferably discharged back to the low-pressure side of the pump and not for lubrication, for example, the rotor shaft is used. The removal of the pumping fluid to be used for the lubrication, takes place at a further inside diameter of the annular chamber of the separation device, where a phase of the pumping fluid has accumulated with low sand concentration.

It goes without saying that in this way, of course, fluid ingredients, such as liquid or viscous high-density ingredients, which contains the Pumplfuid, with the inventive separation device in an analogous manner, such. For example, the portion of pumping fluid to be used for lubrication has a predetermined suitable viscosity, which is not too high, for example, because tougher portions are removable with the separation means.

On the other hand, in order to reliably ensure a flow or a ratio of the throughflows of the pump fluid heavily laden with the ingredient through the discharge opening on the one hand, and of the pump fluid largely purified by the annular gap between the rotor shaft and shaft bearing, a suitable geometry is obtained by means of a loss calculation flowed through cross sections set.

Thus, it is for the first time possible by the present invention not only solid ingredients but also liquid or gaseous ingredients that adversely affect the lubricating behavior to be separated from the pumping fluid to be pumped so that a sufficiently purified of ingredients phase of the pumping fluid is provided can be used for lubricating rotating parts of the pump, wherein the well-known from the prior art harmful influences of the ingredients are largely avoided on the lubrication process. In this case, depending on the precise composition and consistency of the pumping fluid or the ingredients, mixing or solution phenomena, for example, which can further positively influence the process of the separation, can also be relevant. Thus, it is possible, for example, that gas fractions are dissolved in higher viscoses and / or in higher density fluid constituents or are enclosed, for example, in the form of bubbles, and thus likewise separated off by the inventive separation device. Of course For example, other processes known per se can contribute to the fact that not only components of higher density but also of lower density can be deposited via the separation device because they are entrained by the components of higher density.

As already mentioned, in a particularly preferred embodiment for supplying the pumping fluid comprising the ingredient, in particular sand, the separation device is connected to the high-pressure side of the pump via a supply line. In this case, the feed line can be, for example, an integral component of the pump housing, in particular a bore extending in the pump housing or pump stator or bore-like connection opening, or else the feed line can also be realized by a separate line which connects the high-pressure side to the separation chamber.

Specifically, the separation means co-rotating with the rotor shaft about the rotation axis comprises an outer annular chamber to which annular chamber for deposition of the ingredient is provided a substantially tangentially oriented Abscheideöffnung, the Abscheideöffnung particularly preferably for discharging a solid via a Abscheideleitung connected to the low pressure side of the pump is. In this case, of course, the Abscheideleitung in particular an integral part of the pump housing, in particular a running in the pump housing or pump stator bore or hole-like connection opening, or the Abscheideleitung can also be realized by a separate line connecting the separation opening of the separation chamber with the low pressure side Pump connects, or connects to another location with low pressure, the ingredient, so in practice often sand or other liquid or gaseous fluid component of the pumping fluid, while preferably, but not explained above, a higher density than the phase of the pumping fluid used as the lubricating fluid.

Thus, for example, the shaft bearing in which the rotor shaft of the pump is optimally supplied with the cleaned of the ingredient phase of the pumping fluid for lubrication, the lubricating ring gap is in particular fluidly connected in particular by means of a lubricant opening with the separation device that at least partially freed from the ingredient Lubricating fluid to the lubricating ring gap for lubrication of the shaft bearing via the lubricant opening can be fed.

In a specific embodiment, an additional lubricant line can be provided such that a predeterminable amount of lubricating fluid is discharged from the separation device, and can be used to feed a further lubrication point of the pump. In this case, of course, the lubricant line in particular an integral part of the pump housing, in particular a running in the pump housing or pump stator bore or hole-like connection opening, or the lubricant line can also be realized by a separate line, the separation device of the separation chamber with the other lubrication point in the pump connects.

Depending on the application and exemplary embodiment, the separation device can either be detachably connected to the rotor shaft, wherein the separation device can be designed, in particular, as a separation disk which can be screwed to the rotor shaft. It is of course also possible that the separation device is an integral part of the rotor shaft, wherein the separation device may be in particular a separation disc integrally connected to the rotor shaft.

The invention further relates to a separation device for a pump according to the invention wherein the separation device is particularly preferably configured as a separation disc which can be screwed to a rotor shaft of the pump.

In practice, the separation device comprises in particular an outer annular chamber, on which annular chamber for depositing an ingredient, in particular sand, a preferably substantially tangentially oriented separation opening is provided.

The invention finally also relates to a rotor shaft for a pump with a separation device of the present invention, wherein the separation device is particularly preferably releasably connectable to the rotor shaft.

Fig. 1 a

ein Ausführungsbeispiel einer erfindungsgemässen Pumpe mit Separationsscheibe;

Fig. 1 b

die Separationsscheibe der Pumpe gemäss Fig. 1a im Detail;

Fig. 1 c

das Wellenlager der Pumpe gemäss Fig. 1a im Detail;

Fig. 2

eine andere Variante eines Wellenlagers einer erfindungsgemässen Pumpe.

In the following the invention will be explained in more detail with reference to the drawing. In a schematic representation:

Fig. 1 a

an embodiment of an inventive pump with separation disc;

Fig. 1 b

the separation disc of the pump according to Fig. 1a in detail;

Fig. 1 c

the shaft bearing of the pump according to Fig. 1a in detail;

Fig. 2

another variant of a shaft bearing of a pump according to the invention.

Based on Fig. 1a will be discussed in the following a particularly preferred embodiment of an inventive pump with a separation device in the form of a separation disk, wherein Fig. 1b the separation disc and Fig. 1c the construction of the shaft bearing of the pump according to Fig. 1a show in more detail in detail.

The pump according to the invention, which is hereinafter referred to in its entirety by the reference numeral 1, is used very generally and in particular in the specific embodiment of FIG Fig. 1a for the promotion of an ingredient 21 comprising pumping fluid 2. The ingredient 21 in the example of Fig. 1a to 1c is essentially sand, as an impurity in the pumping fluid 2 is present in intolerable quantities. Here, the pumping fluid 2 is petroleum which is provided at an inlet pressure P1 at a low-pressure side LP of the pump 1 and is conveyed to a high-pressure side HP of the pump 1 in the operating state by means of a pump rotor 4 rotatably mounted in a pump stator 3 about a rotation axis A according to the arrow P. , The pump rotor 4 is configured in this way and arranged via a rotor shaft 5 in a shaft bearing 6, that between the rotor shaft 5 and the shaft bearing 6 in a lubricating ring gap 21, a lubricating film 20 from a lubricating fluid 200 formed from the pumping fluid 2 can be formed. According to the invention, a separation device 7 is provided on the rotor shaft 5, with which a predeterminable amount of the ingredient 21 can be separated from the pumping fluid 2 by means of a centrifugal force in the operating state for providing the lubricating fluid 200.

As in Fig. 1a is shown schematically, is for supplying the constituent 21 pumping fluid 2, so here the petroleum, the separation device 7, which is designed as a screwed to the rotor shaft 5 of the pump 1 with screws 70 separation disc, via a supply line 8 with the high pressure side HP of Pump 1 connected. The separation disk is covered by a cover D, through which the pumping fluid 2 is supplied to the separation disk.

According to Fig. 1a respectively. Fig. 1b that the separation disc of the Fig. 1a shown again in more detail in detail, the co-rotating with the rotor shaft 5 around the axis of rotation A separation disc comprises an outer annular chamber 71, wherein on the annular chamber 71 for depositing the ingredient 21, a substantially tangentially oriented Abscheideöffnung 72 is provided. The separation opening 72 is connected to the discharge of the solid 21, so in the present example for discharging the enriched in oil sand, via a Abscheideleitung 9 with the low pressure side LP of the pump 1. The sand has a higher density than the lubricating fluid 200 which, as will be explained below, finally used for lubrication of the rotor shaft 5.

In order for the lubricating fluid 200 to be provided for lubricating the rotor shaft 5 in the shaft bearing 6, the lubricating ring gap 21 is fluidly connected to the separation device 7 by means of a lubricant opening 22 so that the lubricating fluid 200 at least partially freed from the sand is able to lubricate the shaft bearing 6 via the lubrication ring gap 21 Lubricant opening 22 can be supplied.

Furthermore, a lubricant line 10 is additionally provided such that a predeterminable amount of lubricating fluid 200 is discharged from the separation disk, in particular for feeding further lubrication point of the pump 1, which additional lubricant points are not explicitly shown for reasons of clarity. It is even possible that the lubricating fluid 200 branched off via the lubricant line 10 is used for lubricating other parts of the system which are outside the pump 1 or are not part of the pump 1.

As in Fig. 1c shown somewhat schematically, is the separation device 7, so here the separation disc according to Fig. 1a as already briefly mentioned releasably connected to the rotor shaft 5.

However, it is of course also possible in another embodiment that the separation device 7 is an integral part of the rotor shaft 5, and as for example schematically with reference to FIG Fig. 2 illustrated, the separation device 7 is in particular a integrally connected to the rotor shaft 5 separation disc. The embodiment according to Fig. 2 is different from that in Fig. 1c illustrated embodiment only in that the separation disc is integrally connected to the rotor shaft 5 and beyond no additional lubricant line 10 is provided, because in the example of Fig. 2 the Lubricant 200 only for lubrication of the rotor shaft 5, and is needed at no other location.

In all of the exemplary embodiments illustrated here in the figures, the separation line 9 is formed as an integral part in the pump stator 3, but can also be performed as a separate additional Abscheideleitung example, outside the housing of the pump.

It is understood that all embodiments of the invention described above are to be understood as exemplary only or by way of example, and the invention particularly, but not exclusively, includes all suitable combinations of the described embodiments.

Claims (15)

Pump for conveying an ingredient (21) comprising pumping fluid (2), wherein in the operating state, the pumping fluid (2) provided at an inlet pressure (P1) on a low-pressure side (LP) of the pump by means of a in a pump stator (3) about a rotation axis ( A) rotatably mounted pump rotor (4) on a high pressure side (HP) of the pump is conveyed, and the pump rotor (4) configured and arranged via a rotor shaft (5) in a shaft bearing (6) that between the rotor shaft (5) and a lubricating film (20) of a lubricating fluid (200) formed from the pumping fluid (2) can be formed in a lubricating ring gap (21), characterized in that a separation device (7) is provided on the rotor shaft (5) in which, in the operating state for providing the lubricating fluid (200), a predeterminable amount of the constituent (21) can be separated from the pumping fluid (2) by means of a centrifugal force. A pump according to claim 1, wherein for supplying the pump fluid (2) comprising the ingredient (21), the separation means (7) is connected to the high-pressure side (HP) of the pump via a supply line (8). A pump according to claim 1 or 2, wherein the separation means (7) co-rotating with the rotor shaft (5) comprises an outer annular chamber (71) on which annular chamber (71) for depositing the ingredient (21) substantially tangentially oriented separation opening (72) is provided. A pump according to claim 3, wherein the separation port (72) for discharging the solid (21) is connected to the low-pressure side (LP) of the pump via a separation line (9). A pump according to any one of the preceding claims, wherein the ingredient (21) has a higher density than the lubricating fluid (200) and / or the ingredient (21) is a solid, especially sand. Pump according to one of the preceding claims, wherein the lubricating ring gap (21) by means of a lubricant opening (22) with the separation device (7) is fluidly connected, that of the Inhatlsstoff (21) at least partially released lubricating fluid (200) the lubrication ring gap (21) Lubrication of the shaft bearing (6) via the lubricant opening (22) can be fed. Pump according to one of the preceding claims, wherein a lubricant line (10) is provided such that a predetermined amount of lubricating fluid (200) from the separation device (7) is laxative, in particular for feeding a further lubrication point of the pump can be discharged. Pump according to one of the preceding claims, wherein the separation device (7) is detachably connected to the rotor shaft (5), and / or the separation device (7) is designed in particular as a separation disc which can be screwed to the rotor shaft (5). Pump according to one of the preceding claims, wherein the separation device (7) is an integral part of the rotor shaft (5), and / or the separation device (7) is in particular a separation disc integrally connected to the rotor shaft (5). Pump according to one of the preceding claims, wherein the Abscheideleitung (9) is formed as an integral part in the pump stator (3). Separation device for a pump (1) according to one of claims 1 to 10. Separation device according to claim 11, wherein the separation device is designed as a with a rotor shaft (5) of the pump (1) screwable separation disc. Separation device according to one of claims 11 or 12, wherein the separation device comprises an outer annular chamber (71) on which annular chamber (71) for depositing an ingredient (21), in particular sand, a substantially tangentially oriented Abscheideöffnung (72) is provided. Rotor shaft for a pump (1) according to one of claims 1 to 10 with a separation device (7) according to one of claims 11 to 13. Rotor shaft according to claim 14, wherein the separation device (7) is releasably connectable to the rotor shaft.

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