EP2820309A1

EP2820309A1 - Turbomachine having a temperature-controlled cover

Info

Publication number: EP2820309A1
Application number: EP13708721.9A
Authority: EP
Inventors: Ricarda Klett; Erich Muranyi; Dieter Nass; Gregor Senyk
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2012-02-29
Filing date: 2013-02-27
Publication date: 2015-01-07
Also published as: DE102012203144A1; US20150330407A1; WO2013127837A1; CN104160157A

Abstract

The invention relates to a turbomachine (2), comprising a lower housing part (4), an assembly (6) inserted into the lower housing part from above, comprising two opposite housing covers (12) and a rotor (14) having a shaft (16), the rotor being fed through both housing covers, and an upper housing part (8) that encloses the assembly from above and is fastened to the lower housing part. A shaft seal is arranged between the cover (12) and the shaft (16). According to the invention, in order to maintain good function of the shaft seal during operation using cold or hot gases, at least one of the covers (12) has a temperature-control means (28) guided around the shaft (16), having a first and a second temperature-control channel (32, 34), for controlling the temperature of the lid in the area around the shaft (16).

Description

description

The invention relates to a turbomachine with a temp

Lower housing part, a composite inserted into the lower housing part from above - comprising two opposite ones

Housing cover and a guided through both housing cover rotor with a shaft - and a housing upper part, which encloses the composite from above and is secured to the housing lower part.

Turbomachines are used to relax or compress gases. Thus, in a turbine, high pressure inlet gases are introduced into the turbine and relax there, giving energy to the rotor. Compressors in turn serve to compress air or other gases to ultimate pressures of up to 100 bar and more. This aggressive gases can be compressed, which should not get into the environment. Accordingly, turbomachinery are sealed so that their operating gases can not escape or only slightly through the gaps between the shaft and housing to the outside. From GB 219 016 A a turbo-generator arrangement with a turbine arranged in a housing is known. A shaft of the turbine is mounted on separate, outside of the turbine housing and arranged in their own housings bearing blocks. The bearings of the shaft are oil lubricated, which bearing lubricating oil is located within bearing housings of the bearing blocks. Leakage steam from the turbine housing and radiant heat from the turbine housing can result in undesirable heating of the bearing lubricating oil in the bearing housings of the bearing blocks. To counteract this heating, GB 219 016 A provides protective covers bolted to the bearing housings, each of which has water cooling. It is an object of the invention to provide a turbomachine with which a reliable shaft seal can be achieved.

This object is achieved by a turbomachine of the aforementioned type, in which at least one of the covers has a tempering means guided around the shaft for tempering the cover in the region around the shaft. A temperature-related movement of the cover and shaft to each other can be counteracted.

The invention is based on the consideration that turbomachines are subjected to gases, the temperature of which may differ in some cases considerably from the housing temperature of the turbomachine. For example, a turbine is charged with a hot gas that relaxes in the turbine. Accordingly, some elements of the turbine are more heated by the hot gas than others. In the case of compressors, again, it is possible for extremely cold gases to be introduced and compressed, so that they cool the housing considerably at the point of inflow. Depending on the guidance of the operating gas through the turbomachine, different elements of the turbomachine cool at different speeds. This also applies to the two axial covers of the housing, which cool or heat relatively quickly and strongly relative to the shaft and the housing.

In shafts mounted in lids, a shaft seal between the shaft and the axial lugs stored, for example, a labyrinth seal or a fluid seal, which has a gap between its rotating part on the shaft and static part on the lid. If such a cooling or heating affects the sealing area, this can lead to disadvantages with regard to the sealing.

To ensure an optimal seal of the Gap should be as small as possible, but it must be just large enough to avoid abutment of the elements in the operation of the shaft. If the cover cools down around the shaft, it contracts so that the gap grows so that the seal gets worse. The other way round, the gap shrinks when the cover heats up considerably, eg at the gas outlet side of a compressor. In this case, to avoid knocking, the gap must be selected so that it is sufficiently large at all permitted operating temperatures of the lid. As a result, the sealing gap must be relatively large, which is detrimental to a good seal.

While this problem can be satisfactorily solved in smaller machines by a good bearing of the shaft and a clever dimensioning of the sealing gap, the problem is to be solved in a complex manner with large machines. Because of the large dimensions of the lid and the thermal expansion per degree of temperature movement is correspondingly large, so that the sealing gap at a cooling of the lid to

100 K can move several millimeters. Such temperature movements are more difficult to solve by a good thermal insulation of the lid and a clever dimensioning of the sealing gap in such a way that a good seal of the shaft is achieved.

Large machines are characterized, inter alia, by the fact that their lid sealing can take place over two or more sealing stages, wherein the inner stage has a larger diameter than the outer stage. The lid can be pressed in this construction to seal against the housing axially outward against the seals. However, this design makes it necessary to insert the rotor together with the two covers as a mounting unit or as a composite in the lower part of the housing.

By the temperature control of the lid, the lid of During operation, large machines are heated in the area around the shaft in such a way that the gap changes little during operation, so that its dimensions remain close to an optimum gap thickness for the sealing. On a complex thermal insulation of the lid can be dispensed with or the insulation effort can be kept low.

The temperature control medium may be a heating medium and / or a coolant. Conveniently, it can be used both for cooling and for heating. This is particularly advantageous in the case of a compressor, since in this case the housing cover at the gas inlet cools due to the entry of cold gases and the

Housing cover at the gas outlet is heated by escaping hot gases. By means of the temperature control, which is suitably operated in both lids in the same way, the housing cover can be heated at the gas inlet and the

Housing cover to be cooled at the gas outlet. The turbomachine may be a relaxation machine, such as a turbine, or a compressor, for example a turbocompressor, in particular a one-shaft radial compressor. The composite may contain, in addition to the cover and the rotor, further elements, for example a flow guide, in particular a Eintrittsleitapparat.

In an advantageous embodiment of the invention, the temperature control means is guided around a shaft seal, which is arranged between the cover and the shaft. As a result, the shaft seal can be protected from all sides by the externally acting undesirable temperature, heat or cold.

A tempering of the lid, in particular the sealing area of the lid around the shaft around, can be done in several ways. Heating coils can be used, but their electricity must be well shielded. The use of heating pads is possible, but well sealed and must be pressure-resistant. It is particularly advantageous, if the temperature control means has a first temperature control channel in the cover, which fluidly with a

Temperierflüssigkeitsreservoir is connected. In this way, tempering liquid can be brought to a desired temperature and passed around the shaft or the shaft seal, where it gives off its heat or cold.

For this purpose, the presence of a tempering liquid is necessary, which can be any meaningful liquid. However, if bearing oil is used as the tempering liquid provided for supporting the shaft, then the bearing oil is used for a number of purposes, so that it is possible to dispense with a further liquid reservoir and an additional liquid temperature control agent.

Advantageously, the temperature control channel is incorporated lengthwise directly into the cover, so that the

Temperature control fluid flows directly through the lid. Particularly advantageous is the tempering channel incorporated into the inner side of the lid. Since this comes directly in connection with the operating gas, it is particularly cold or hot, so that the lid from there strongly cools down or heated. If the tempering channel is incorporated into the inner side of the lid, this undesirable effect of temperature can be counteracted particularly effectively. On the inner side of the lid may be a Strömungsleitapparat, which may be an Eintrittsleitapparat or a Austrittsleitapparat.

In a further advantageous embodiment of the invention, the temperature control means has a second temperature control channel arranged radially outside the first temperature control channel.

As a result, a particularly complete Temperaturabschir- mung the sealing area can be achieved. The second

Temperature control can be directly connected to the first temperature control, so that a flow through both channels takes place successively, or be separated, so that, for example, a parallel flow occurs.

Conveniently, the tempering channel is open-ring guided around the shaft. In particular, if it is in an axial plane, the ring must be open to allow an inlet and an outlet. Through this opening of the ring, which is referred to below as tempering channel-free gap, heat or cold can penetrate radially from the outside into the inner region of the channel and thus to the shaft seal. In order to avoid this, it is further proposed that the second tempering channel is guided around the first tempering channel such that a tangential gap free of tempering channel in the region of the first tempering channel is shielded radially outwardly from the second tempering channel.

The closer a cover area to the shaft seal, the more important is its accurate temperature control. To achieve this, it is beneficial if the two

Temperierkanäle are interconnected so that

Temperierflüssigkeit from Temperierflüssigkeitsreservoir first through the radially inner tempering and from there into the radially outer Temperierkanal flows before it returns to the Temperierflüssigkeitsreservoir.

Unwanted heat or cold can penetrate not only from radially outward to the shaft seal, but also in the axial direction. Therefore, it is advantageous if there are temperature control channels of different function, in particular a radial shielding function and an axial shielding function. Both functions can be achieved if both tempering channels have a rectangular cross section and one of the

Temperature control channels has a longer extent in the axial direction and the other of the temperature control channels a longer extent in the radial direction. With a longer extension in the axial direction, a radial shield and at a longer extension in the radial direction axial shielding can be achieved. Expediently, the radially outer tempering channel has a longer extent in the axial direction and the radially inner tempering channel has a longer extent in the radial direction. As a result, the radially innermost region can be shielded most effectively against heat or cold from an inlet guide device.

In a further advantageous embodiment of the invention, a gas supply for a shaft seal is guided radially between two temperature control channels of the temperature control. As a result, gas guided to the shaft seal can be kept at a desired temperature, thus maintaining a good seal. The shaft seal may be a gas or oil-operated fluid seal. Also a labyrinth seal is possible.

The above-described characteristics, features and advantages of the invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of an embodiment which is explained in more detail in connection with the drawings. The embodiment is illustrative of the invention and does not limit the invention to the combination of features set forth therein, including functional features. In addition, suitable features of the embodiment may also be considered explicitly isolated and combined with any of the claims. Show it:

1 shows a schematic sectional view of a turbomachine, FIG. 2 shows a housing lower part of the turbomachine with an inserted lid, 3 shows a sectional view of a radially inner part of the cover around the shaft with several

Temperierkanälen and 4 shows an axial plan view of the leadership of two

Temperature control channels.

In large flow machines, the housing is in one

Housing base and an upper housing part in two parts. For mounting the turbomachine is the first

Housing bottom set and then a rotor assembly is inserted from above into the housing base. This is shown schematically in FIG. The lower housing part 4 of the turbomachine 2 stands on a solid surface and the composite 6 is lowered from above into the lower housing part 4. Subsequently, the upper housing part 8 on the

Housing base 4 placed and screwed with this, so that the entire housing 10 results. The composite is enclosed by the housing 10, wherein two cover 12 of the composite 6 remain visible from the outside and can also be referred to as part of the housing 10. The two covers 12 in turn are connected to the rotor 14, the shaft 16 is passed through the two covers 12 and is sealed in the two covers 12 with a shaft seal, not shown. The rotor comprises in addition to the shaft 16 a plurality of impellers of the turbomachine. Cover 12 and rotor 14 with shaft 16, and possibly other components, form the composite. 6

2 shows the lower housing part 4 with one of the two disgust 12 in a rough perspective view. The turbomachine 2 in this exemplary embodiment is a single-shaft radial compressor with a gas inlet 18 and a gas outlet 20. The gas to be compressed flows through the gas inlet 18 into the turbomachine 2, is compressed by the rotation of the rotor 14 and leaves the turbomachine 2 in compacted and heated state through the gas outlet 20. About supports 22, the lower housing part 4 is fixed to the solid floor. FIG 2 shows no mounting state of the turbomachine 2, since the lid 12 for better representability half individually and without the rotor 14 and the other opposite lid 12 is shown. Completely FIG 2 should be thought that the lid 12 shown is placed on the shaft 16 of the rotor 14 and the opposite cover 12 is also positioned on the shaft 16. This composite 6 is now stored in the housing lower part 4 in the state shown in FIG.

3 shows a radially inner part of the lid 12 about the shaft 16 in a sectional view. In a sealing region 24 a plurality of sealing elements 26 of a shaft seal are arranged, which shields an inner gas region of the compressor 2 against the outside of the compressor 2 atmospherically. Axially in the sealing region 24, the cover 12 has a temperature control means 28 which comprises a plurality of temperature control channels 32, 34. For good temperature control of sealing fluid, a fluid supply 36 for supplying gas or sealing oil to at least one of the sealing elements 26 is arranged between the temperature control channels 32, 34. Axially further out, a bearing 38 of the shaft 16 in a bearing block 40 is shown. Axially inside the cover 12, a housing cover insert 42 of a Eintrittsleitapparats is shown, which directs the incoming and to be compressed operating gas to the blades of the rotor 14.

The two temperature control channels 32, 34 are shown in FIG 4 in a schematic axial sectional view. Bearing oil as tempering liquid is in one

Temperierflüssigkeitsreservoir 44 stored, pumped from there to a heater 46, which can also be used as a cooler for cooling the bath liquid, and there brought to a desired temperature, that is cooled or heated relative to the environment. Via a supply line 48, the bath liquid reaches the radially inner tempering 34, flows around the not shown shaft 16 annular in a not completely closed circuit to reach via a connecting channel 50, the outer tempering 32. There, the temperature-control liquid flows again in a ring-shaped manner around the shaft 16 in a tangentially opposite direction in the outer temperature-control channel 32, in order then to be returned to the temperature-control liquid reservoir 44 via an outlet 52.

By the opposite tangential flow direction in the two tempering channels 32, 34 a uniform tangential temperature of the lid 12 is reached around the shaft 16. The radially innermost temperature control channel 34 is supplied with the supply 48 directly with heat transfer fluid from the heater 46, so that there the temperature is precisely adjustable, which is particularly advantageous in the innermost region of the lid 12.

The two tempering channels 32, 34 are guided towards one another in such a way that the radially outer tempering channel 32 extends radially around a tangential tempering channel-free gap 54 of the inner ring

Temperature control channel 32 is guided, so that the shaft 16 is shielded in the radial direction in the region of the gap 54 from the outer temperature control channel 32. The outer tempering 32 is designed as a radial channel, its function is primarily in the radial temperature shield. Accordingly, its rectangular, oblong cross section in the axial direction is longer than in the radial direction. The radially inner tempering channel 34 is designed as an axial channel, its function is primarily in the axial temperature shield. Accordingly, its rectangular, elongated cross section is longer in the radial direction than in the axial direction. Instead of the axial channel 34, a further radial channel may be present.

Both tempering channels 32, 34 are introduced into the inside of the lid 12. Through the axial channel 34, the cover 12 is mainly against cold from the flow control or Housing cover insert 42 shielded. The radial channel 32 shields the inner region of the cover 12 from cold from the gas inlet 18, which predominantly penetrates radially from outside to inside the cover 12.

Through all channels 32, 34, the inner portion of the lid 12 is shielded against the outgoing and outgoing gas to be compressed outgoing cold, so that the inner region of the lid 12 and thus the shaft seal is maintained in a desired temperature range.

FIGS. 3 and 4 only show the axial cover 12 of the housing 10 located at the gas inlet 18. Equally, however, the cover 12 is also formed at the outlet 20. It also contains the temperature control channels of the same design, which are connected to the temperature control reservoir 44 parallel to the temperature control channels 32, 34 of the inlet-side cover 12. They are therefore fed with the same heat transfer fluid, which is guided by leads 48 at the same temperature to two lids 12. Since the inlet-side cover 12 is cooled by the operating gas and the outlet-side cover 12 is heated, the same liquid assumes different functions in both covers 12, namely the heater in the inlet-side cover 12 and the cooling in the outlet-side cover 12.

Although the invention has been further illustrated and described in detail by the preferred embodiments, the invention is not limited to the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims

claims

1. Turbomachine (2) with a lower housing part (4), in the lower housing part (4) from above inserted composite (6) - comprising two opposite housing cover (12) and a through both housing cover (12) guided through rotor (14) a shaft (16) - and a housing upper part (8) which surrounds the composite (6) from above and on

Housing base (4) is attached,

characterized in that at least one of the covers (12) has a tempering means (28) guided around the shaft (16) for tempering the cover (12) in the region around the shaft (16).

2. Turbomachine (2) according to claim 1,

characterized in that between the cover (12) and the shaft (16) a shaft seal is arranged and the

Temperature control (28) is guided around the shaft seal.

3. Turbomachine (2) according to claim 1 or 2,

characterized in that the temperature control means (28) comprises a first tempering channel (32, 34) in the lid (12), which is fluidly connected to a Temperierflüssigkeitsreservoir (44).

4. flow machine (2) according to claim 3,

characterized in that the bath fluid is bearing oil, which is provided for supporting the shaft (16).

5. Turbomachine (2) according to claim 3 or 4,

characterized in that the tempering channel (32, 34) is incorporated in the inside of the lid (12).

6. turbomachine (2) according to one of claims 3 to 5, characterized in that the temperature control means (28) has a radially outside of the first temperature control channel (34) arranged second temperature control channel (32).

7. flow machine (2) according to claim 6,

characterized in that the second tempering (32) is guided around the first tempering (34) that a tangential temperierkanalfreie gap (54) in the region of the first tempering (34) radially outwardly from the second tempering (32) is shielded.

8. Turbomachine (2) according to claim 6 or 7,

characterized in that the two temperature control channels (32, 34) are connected to each other such that the temperature control liquid from the Temperierflüssigkeitsreservoir (44) first through the radially inner tempering (34) and from there into the radially outer tempering (32) flows before entering the

Temperierflüssigkeitsreservoir (44) returns.

9. Turbomachine (2) according to one of claims 6 to 8, characterized in that both tempering (32, 34) have a rectangular cross-section and the radially outer tempering (32) a longer extension in the axial direction and the radially inner tempering ( 34) has a longer extent in the radial direction.

10. Turbomachine (2) according to one of the preceding claims,

characterized in that a gas supply (36) for a

Shaft seal radially between two temperature control channels (32, 34) of the temperature control (28) is guided.