TURBINE HOUSING AND METHOD FOR MOUNTING A TURBINE WITH A TURBINE HOUSING

Description

[0001] The present invention relates to a multi-part turbine housing, in particular for a steam turbine, and a method for assembling a multi-part turbine housing, in particular for a steam turbine.

[0002] Steam turbines are turbomachines designed to convert the enthalpy of steam into kinetic energy. Conventional steam turbines have a turbine casing surrounding a flow chamber through which steam flows. Arranged within the flow chamber is a rotary-mounted turbine shaft with a plurality of rotor blades, which are held on the turbine shaft in the form of successively arranged rotor blade rings. To optimize the flow of steam to the rotor blades, steam turbines have guide vane rings, each of which is arranged upstream of a rotor blade ring and held on the turbine casing. A group consisting of a guide vane ring with the associated rotor blade ring is also referred to as a turbine stage.

[0003] As the steam flows through the steam turbine, it releases some of its internal energy, which is converted into rotational energy for the turbine shaft via the rotor blades. This causes the steam to expand, reducing its pressure and temperature as it flows through the steam turbine after each turbine stage. The turbine casing is thus exposed to a temperature gradient between the steam inlet and steam outlet. This leads to very high stress on the turbine casing, especially in compact steam turbines.

[0004] To improve efficiency, steam turbines in special embodiments have several turbine sections, such as a high-pressure section, a medium-pressure section and / or a low-pressure section. To further improve efficiency, such steam turbines can have a heating device for intermediate superheating of the steam, so that, for example, steam leaving the high-pressure section can be heated by the heating device before it is fed to the subsequent turbine sections. It can be provided that such a heating device is arranged between each two turbine sections. Particularly in steam turbines with such intermediate superheating of the steam, strong temperature fluctuations occur along a longitudinal axis of the steam turbine. Initially, the temperature in the high-pressure section drops gradually, then rises abruptly in the transition region due to the intermediate superheating.An area of ​​the turbine housing which is arranged adjacent to an outflow of the high-pressure section and an inflow of the following medium-pressure section or low-pressure section is exposed to particularly strong temperature differences, especially in compact steam turbines.

[0005] Furthermore, for reasons of improved manufacturability and assembly, turbine housings comprise multiple housing sections that are connected to form the turbine housing by forming joints. Turbine housings often comprise a lower housing section and an upper housing section. The turbine housing can also comprise multiple housing segments along the turbine's longitudinal axis, so that the high-pressure section and the medium-pressure section, for example, are arranged in different housing segments. The connection is often achieved by bolting vertical flanges, i.e., flanges of the housing sections or housing segments, with the flanges extending annularly on a plane transverse to the turbine's longitudinal axis.

[0006] In turbine casings which, for example, have at least one front casing segment with a first front casing part segment and a second front casing part segment, as well as a rear casing segment with a first rear casing part segment and a second rear casing part segment, a cross-part joint is formed at a joint between four casing part segments. Vertical flanges and horizontal flanges meet at cross-part joints of turbine casings. Ensuring high vapor tightness is particularly problematic at such cross-part joints. High temperature loads, such as temperature fluctuations, temperature gradients or extreme temperatures, as well as high pressure loads, such as pressure fluctuations, pressure gradients or extreme pressures, increase the risk of a leak associated with the suction of ambient air into the casing or leakage of the working medium at a cross-part joint.High overpressures in particular increase the risk of leaks at cross-section joints.

[0007] There are several different approaches to preventing leaks at cross-joints. By increasing the bolt force for connecting the flanges of adjacent casing segments and by using oversized components, the tightness of cross-joints can be improved. The disadvantages of this approach are increased material and assembly requirements, and thus increased manufacturing costs for the turbine casing. Alternatively or additionally, operating parameters can be restricted to avoid critical limits that would lead to excessive stress on the cross-joints. This measure reduces the performance and often also the efficiency of the turbine.

[0008] WO 2016 / 082956 A1 discloses a vertically segmented turbine housing consisting of two horizontally divided sub-segments to prevent leaks at cross-section joints. EP 3 059 400 A1 discloses a similar connection of two vertical flanges with a sealing device. Another example is known from EP 2 915 960.

[0009] It is therefore the object of the present invention to provide a turbine housing for a turbine and a method for assembling a turbine with a turbine housing according to the invention, which eliminate or at least partially eliminate the disadvantages of the prior art. In particular, the object of the present invention is to provide a turbine housing for a turbine, in particular a steam turbine, and a method for assembling a turbine, which ensure improved tightness at cross-section joints using simple means and at low cost.

[0010] The above object is achieved by the patent claims. Accordingly, the object is achieved by a turbine housing for a turbine, in particular a steam turbine, according to claim 1. Furthermore, the above object is achieved by a method for assembling a turbine, in particular a steam turbine, with a turbine housing according to the invention according to claim 10. Further features and details of the invention emerge from the subclaims, the description and the drawings. Features and details that are described in connection with the turbine housing according to the invention naturally also apply in connection with the method according to the invention and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reciprocal reference is and can always be made.

[0011] According to a first aspect of the invention, the object is achieved by a turbine housing for a turbine, in particular a steam turbine. The turbine housing has a front housing segment formed around a turbine longitudinal axis, comprising a first front housing sub-segment and a second front housing sub-segment, and a rear housing segment formed around the turbine longitudinal axis, comprising a first rear housing sub-segment and a second rear housing sub-segment. The rear housing segment is arranged behind the front housing segment in the flow direction of the turbine and is fastened to a front vertical flange of the front housing segment on the front housing segment, forming a cross-part joint via a rear vertical flange of the rear housing segment.According to the invention, a projection surrounding the turbine's longitudinal axis is formed on the front housing segment in a region of the front vertical flange. This projection extends parallel or at least substantially parallel to the turbine's longitudinal axis and projects beyond the front vertical flange in the flow direction. A circumferential sealing device is arranged on an outer side of the projection facing away from the turbine's longitudinal axis, sealing the projection against the rear housing segment.

[0012] The front housing segment and the rear housing segment are formed around the turbine's longitudinal axis, on which a rotor shaft of the turbine with rotor blade rings can preferably be arranged coaxially. Dividing the turbine housing into housing segments improves and ensures assembly and disassembly of the rotor shaft and other turbine components, such as bearings, seals, guide vane rings, or the like, and allows the turbine housing to be manufactured and transported more cost-effectively. The turbine's longitudinal axis is preferably formed on a horizontal plane.

[0013] The front housing segment has a front horizontal flange that extends parallel or at least substantially parallel to the longitudinal axis of the turbine. The front horizontal flange is formed partially on the first front housing part segment and partially on the second front housing part segment. The first front housing part segment and the second front housing part segment are connected to one another via the front horizontal flange, in particular by means of screws, bolts or the like. The rear housing segment has a rear horizontal flange that extends parallel or at least substantially parallel to the longitudinal axis of the turbine. The rear horizontal flange is formed partially on the first rear housing part segment and partially on the second rear housing part segment.The first rear housing segment and the second rear housing segment are connected to each other via the rear horizontal flange, in particular by means of screws, bolts, or the like. Within the scope of the invention, a horizontal flange is understood to mean a flange that extends on a plane on which the turbine's longitudinal axis runs or to which the turbine's longitudinal axis runs at least parallel. This plane is preferably oriented horizontally, but depending on the turbine design, it can have an inclination of between 0° and 90° to the horizontal plane.

[0014] The front housing segment has a front vertical flange that faces the rear housing segment and is adjacent thereto and extends in the radial direction with respect to the flow direction. The front vertical flange is formed partially on the first front housing part segment and partially on the second front housing part segment. Accordingly, the rear housing segment has a rear vertical flange that faces the front housing segment and is adjacent thereto and extends in the radial direction with respect to the flow direction. The rear vertical flange is formed partially on the first rear housing part segment and partially on the second rear housing part segment. The front housing segment is connected to the rear housing segment via the front vertical flange and the rear vertical flange, in particular by means of screws, bolts or the like.In the context of the invention, a vertical flange is a flange that extends on a plane that is preferably perpendicular to the longitudinal axis of the turbine: depending on the embodiment, it can be provided that this plane is inclined by between 0° and 90° about an axis that runs horizontally and transversely to the longitudinal axis of the turbine.

[0015] The projection is preferably designed as an extension of the front housing part segment, which projects beyond the front vertical flange in the flow direction. A wall thickness of the projection is preferably less than a wall thickness or average wall thickness of the front housing part segment. This has the advantage that a direct flow of a parting line between the front vertical flange and the rear vertical flange by an operating fluid of the turbine flowing in the flow direction or essentially in the flow direction can be prevented in this way. The outer side of the projection faces away from the longitudinal axis of the turbine and is surrounded in the radial direction by the rear housing segment.

[0016] The sealing device arranged on the outside completely surrounds the turbine's longitudinal axis. The sealing device closes a gap formed between the projection and the rear housing segment, thus sealing the turbine housing interior from the cross-parting joint. One region of the sealing device is preferably designed according to a known piston seal. Within the scope of the invention, it can be provided that the sealing device is fixed to the projection or the rear housing segment.

[0017] Preferably, a mounting hole diameter is larger than the outer diameter of the projection. Thus, the connection points of the front vertical flange and the rear vertical flange are covered by the projection relative to the turbine housing interior.

[0018] A turbine housing according to the invention has the advantage over conventional turbine housings that it exhibits particularly reliable and high tightness at the cross-parting joint, particularly due to the projection and the sealing arrangement. A further advantage is that the turbine housing according to the invention is particularly suitable for small and / or compact turbines and can be designed for relatively extreme operating parameters, in particular high overpressures and high temperatures.

[0019] According to a preferred development of the invention, in a turbine housing, the projection can be designed in the shape of a hollow cylinder or substantially hollow cylinder, or in the shape of a hollow cone or substantially hollow cone. Such a projection has an annular cross-section. In the case of a hollow cone-shaped projection, the cone is preferably designed as an outer cone on the outside. The outer cone is preferably designed such that, when the front housing segment is joined to the rear housing segment, a compressive force can be built up via the outer cone, which can be transmitted via the sealing device. Further preferably, an inner cone is formed on an inner side of the rear housing segment, which inner cone can be brought into engagement with the outer cone when the front housing segment is joined to the rear housing segment.In this way, the tightness of the turbine housing can be further improved using simple means. A projection according to the invention also has the advantage that a contact joint between the front vertical flange and the rear vertical flange is completely or essentially completely covered.

[0020] Further preferably, the sealing device is arranged and configured to seal the projection against the rear vertical flange. The projection and the rear vertical flange thus form a common overlap region. It is preferred that the projection completely or at least substantially completely overlap the rear vertical flange. Alternatively, it can be provided that the projection partially overlaps the rear vertical flange or protrudes beyond it in the flow direction. Such an arrangement of the sealing device has the advantage that a particularly good sealing effect can be achieved due to the particularly high stability of the rear housing segment in the region of the rear vertical flange.

[0021] Preferably, at least one circumferential groove is formed in the outer side of the projection. The sealing device has at least one sealing ring, which has at least a first ring segment and a second ring segment. The at least one sealing ring is at least partially received in the at least one groove and makes sealing contact with the rear housing segment in the radial direction with respect to the longitudinal axis of the turbine. Within the scope of the invention, it can be provided that the at least one groove is formed on the inner side of the rear housing segment and the sealing ring is at least partially received in the at least one groove and makes sealing contact with the outer side of the projection.Alternatively, the outer side of the projection and the inner side of the rear housing segment can each have at least one groove in which the sealing device is at least partially arranged, thus sealing the projection and the rear housing segment. To improve the seal, several grooves with several sealing rings can be provided. A groove has the advantage that the sealing device can be secured against axial displacement along the turbine's longitudinal axis using simple and cost-effective means. Furthermore, an improved sealing effect can be achieved by means of a groove.

[0022] Furthermore, it is preferred that the at least one first ring segment and the at least one second ring segment have end regions that at least partially overlap one another in the circumferential direction to form a gas-tight joint, which end regions are preferably designed in accordance with conventional piston rings. Overlapping end regions have the advantage that an optimal sealing effect can be achieved by a higher pressure on one side than on the other side, as seen along the turbine's longitudinal axis, and that diameter changes can be compensated for.

[0023] According to the invention, at least one first end region of the at least one first ring segment can have at least one recess formed in the circumferential direction, and at least one second end region of the at least one second ring segment can have at least one tongue projecting in the circumferential direction, wherein the at least one tongue is designed for positive engagement in the at least one recess. Preferably, the end regions are designed such that, upon assembly, the ring segments are positively centered. By means of such a design, ring segments can be easily joined together to form a sealing ring, forming a good seal.

[0024] It is preferred that the at least one sealing ring has an outer ring diameter that, at least in a relieved state, is larger than a rear housing segment inner diameter of the rear housing segment. Within the scope of the invention, a relieved state of the ring is a state in which the ring is not constrained. Once installed, it can be reduced to a somewhat smaller diameter, even when no working fluid is flowing through the turbine and the internal pressure of the turbine corresponds to ambient pressure. The oversize of the outer ring diameter is such that assembly of the housing segments with the sealing ring is still possible without restriction. Due to the larger diameter of the sealing ring, it forms a press fit when the housing segments are joined together. This ensures a high level of tightness of the turbine housing.

[0025] In an advantageous embodiment of the invention, a bore is formed in the rear vertical flange, which connects an intermediate space formed between the sealing device and the front vertical flange to a second interior region of the rear housing segment in a fluid-communicating manner. The second interior region is arranged in the flow direction behind a first interior region directly adjacent to the front housing segment within the rear housing segment. Working fluid flowing through the turbine thus first flows through the first interior region and then flows on into the second interior region. The bore is preferably formed in a wall of the rear housing part segment. Alternatively, a pipeline can also be arranged at the bore, which connects the bore to the second interior region in a fluid-communicating manner.A bore has the advantage that working fluid penetrating the gap, i.e., working fluid that has overcome the sealing device, can be diverted by a joint between the front vertical flange and the rear vertical flange, as well as a joint between the first horizontal flange and the second horizontal flange. This prevents unintentional air intake into the rear housing segment.

[0026] Further preferably, the first front housing segment is designed as the high-pressure turbine housing lower part of a high-pressure part of the turbine housing, the second front housing segment is designed as the high-pressure turbine housing upper part of the high-pressure turbine housing, the first rear housing segment is designed as the exhaust steam housing lower part of an exhaust steam housing of the turbine housing, and the second rear housing segment is designed as the exhaust steam housing upper part of the exhaust steam housing. Conventional turbines have such a division of the housing segments, as this ensures both simple assembly and disassembly and reliable operation of the turbine.

[0027] According to a second aspect of the invention, the object is achieved by a method for assembling a turbine with a turbine housing according to the invention. The method comprises the following steps: Inserting the first ring segment of the sealing ring into the groove of the projection of the high-pressure turbine housing lower part, connecting the high-pressure turbine housing lower part to the exhaust steam housing lower part to form a housing lower part, inserting internal components of the turbine into the housing lower part, inserting the second ring segment of the sealing ring into the groove of the projection of the high-pressure turbine housing upper part, connecting the high-pressure turbine housing upper part to the exhaust steam housing upper part to form a housing upper part and placing the housing upper part on the housing lower part.

[0028] The first ring segment of the sealing ring is inserted into the groove of the projection of the high-pressure turbine housing lower section and secured against falling out. Preferably, the first ring segment is releasably fixed in the groove, in particular by means of a screw or adhesive connection. The adhesive connection preferably has properties such that it releases under temperature during the initial operation of the turbine. Insertion is preferably carried out such that the end regions of the first ring segment are adjacent, in particular equally adjacent, to the horizontal flange of the high-pressure turbine housing lower section.

[0029] The high-pressure turbine housing lower section is then connected to the exhaust steam housing lower section to form the housing lower section. The first ring segment is engaged with the exhaust steam housing lower section to create a seal. The connection is made via the vertical flanges formed on the high-pressure turbine housing lower section and the exhaust steam housing lower section, in particular by means of screws, bolts, or the like. It is preferred that at least one centering rod is used when joining the high-pressure turbine housing lower section and the exhaust steam housing lower section in order to optimally align the high-pressure turbine housing lower section and the exhaust steam housing lower section. Preferably, at least two centering rods are used for this purpose.

[0030] The turbine's internal components are preferably inserted into the lower housing section such that a rotor longitudinal axis is aligned with the turbine's longitudinal axis. The internal components can be arranged on both the high-pressure turbine housing section and the exhaust steam housing section. According to the invention, it is preferred that at least some of the internal components be releasably fixed to the lower housing section.

[0031] The second ring segment of the sealing ring is inserted into the groove of the projection of the high-pressure turbine housing upper section and secured against falling out. Preferably, the second ring segment is releasably fixed in the groove, in particular by means of a screw or adhesive connection. The adhesive connection preferably has properties such that it releases under temperature during the initial operation of the turbine. Insertion is preferably carried out such that the end regions of the second ring segment are adjacent, in particular equally adjacent, to the horizontal flange of the high-pressure turbine housing upper section.

[0032] The high-pressure turbine housing upper section is then connected to the exhaust steam housing upper section to form the housing upper section. The second ring segment is engaged with the exhaust steam housing upper section to create a seal. The connection is made via the vertical flanges formed on the high-pressure turbine housing upper section and the exhaust steam housing upper section, in particular by means of screws, bolts, or the like. It is preferred that at least one centering rod is used when joining the high-pressure turbine housing upper section and the exhaust steam housing upper section in order to optimally align the high-pressure turbine housing upper section and the exhaust steam housing upper section. Preferably, at least two centering rods are used for this purpose.

[0033] In a subsequent process step, the upper housing section is placed on the lower housing section and releasably secured thereto. During placement, the upper and lower housing sections are aligned relative to each other, preferably using at least one centering rod. Preferably, at least two centering rods are used for this purpose. Furthermore, the lower housing section is arranged in a constant position, so that only the upper housing section is moved during alignment and placement.

[0034] The method according to the invention for assembling a turbine with a turbine housing according to the invention has the same advantages as already described above for a turbine housing according to the first aspect of the invention. Accordingly, the method according to the invention has the advantage that a turbine with a turbine housing can be assembled using simple means and cost-effectively, which exhibits particularly high and reliable tightness in the region of the cross-parting joint of the turbine housing. The method according to the invention is particularly suitable for assembling small and / or compact turbines that can be operated under relatively extreme operating parameters, in particular high overpressures and high temperatures, and yet exhibit a high degree of tightness.

[0035] A turbine housing according to the invention and a method according to the invention are explained in more detail below with reference to the drawings. They show schematically: Figure 1 shows a side view of a preferred first embodiment of a turbine housing according to the invention, Figure 2 shows an enlarged section of the turbine housing in longitudinal section Fig. 1 , Figure 3 shows in longitudinal section an enlarged section of a preferred second embodiment of a turbine housing according to the invention, Figure 4 shows in plan view a preferred sealing ring and Figure 5 shows an enlarged section of end regions of the sealing ring from Fig. 4 .

[0036] In Fig. 1 A preferred first embodiment of a turbine housing 1 according to the invention is shown schematically in a side view. The turbine housing 1 extends along a longitudinal turbine axis 2 and has a front housing segment 3 designed as a high-pressure turbine housing 19 and a rear housing segment 4 designed as an exhaust steam housing 20. The rear housing segment 4 is arranged behind the front housing segment 3 in the flow direction D of the turbine housing 1. The front housing segment 3 has a first front housing part segment 3a designed as a high-pressure turbine housing lower part 19a and a second front housing part segment 3b designed as a high-pressure turbine housing upper part 19b.The first front housing segment 3a and the second front housing segment 3b are detachably connected to one another via a horizontal flange (not shown), which is formed partially on the first front housing segment 3a and partially on the second front housing segment 3b. The rear housing segment 4 has a first rear housing segment 4a formed as an exhaust steam housing lower part 20a and a second rear housing segment 4b formed as an exhaust steam housing upper part 20b. The first rear housing segment 4a and the second rear housing segment 4b are detachably connected to one another via a horizontal flange (not shown), which is formed partially on the first rear housing segment 4a and partially on the second rear housing segment 4b.The rear housing segment 4 has a first interior region 18a and a second interior region 18b, wherein the second interior region 18b is arranged behind the first interior region 18a in the flow direction D.

[0037] At a rear end in the flow direction D, the front housing segment 3 has a circumferential front vertical flange 7 which surrounds the turbine longitudinal axis 2 and preferably has parting lines only in the region of the transitions between the first front housing part segment 3a and the second front housing part segment 3b. At a front end in the flow direction D, the rear housing segment 4 has a circumferential rear vertical flange 6 which surrounds the turbine longitudinal axis 2 and preferably has parting lines only in the region of the transitions between the first rear housing part segment 4a and the second rear housing part segment 4b. A cross parting line 5 is formed in a region adjacent to the first front housing part segment 3a, the second front housing part segment 3b, the first rear housing part segment 4a and the second rear housing part segment 4b.

[0038] In Fig. 2 is an enlarged section of the turbine housing 1 from Fig. 1 shown schematically. In this view, it can be seen that a projection 8 is formed on the front vertical flange 7 of the front housing segment 3, which projection 8 extends in the flow direction D over a width of the rear vertical flange 6 of the rear housing segment 4. At a position extending from the turbine longitudinal axis 2 (cf. Fig. 1 On the outer side 9 facing away from the turbine housing 1, the projection 8 has a groove 11 in which a sealing ring 12 of a sealing device 10 is arranged and fixed. The sealing ring 12 extends in the radial direction R and contacts the rear vertical flange 6. Thus, a vertical joint between the front vertical flange 7 and the rear vertical flange 6 is sealed to an interior of the turbine housing 1. According to the invention, a plurality of sealing rings 12 can also be provided.

[0039] Fig. 3 shows schematically an enlarged section of a preferred second embodiment of a turbine housing 1 according to the invention. In this second embodiment, a bore 16 is formed which runs parallel to the flow direction D and opens into an intermediate space 17 which is formed between the sealing device 10 and the front vertical flange 7. Working fluid which has passed the sealing device 10 can be discharged via the bore 16. Another end of the bore 16 opens into the second interior region 18b of the rear housing segment 4. The sealing device 10 in this example has two sealing rings 12, each of which is arranged in a groove 11 in the outer side 9 of the projection 8. According to the invention, one or more sealing rings 12 can be provided.

[0040] Fig. 4 und Fig. 5show a preferred sealing ring 12 or a section of the sealing ring 12 in a plan view in the flow direction D. The sealing ring 12 has a first ring segment 12a and a second ring segment 12b, which are or can be connected to one another in end regions 13 to form a gas-tight joint. A first end region 13a of the first ring segment 12a has a tongue 15, which is designed for positive engagement in a recess 14 of a second end region 13b of the second ring segment 12b. List of reference symbols

[0041] 1Turbine casing 2Turbine longitudinal axis 3Front casing segment 3aFirst front casing part segment 3bSecond front casing part segment 4Rear casing segment 4aFirst rear casing segment 4bSecond rear casing segment 5Cross-section joint 6Rear vertical flange 7Front vertical flange 8Protrusion 9Outside 10Sealing device 11Groove 12Sealing ring 12aFirst ring segment 12bSecond ring segment 13End area 13aFirst end area 13bSecond end area 14Recess 15Tent 16Bore 17Gap 18aFirst interior area 18bSecond interior area 19High-pressure turbine casing 19aHigh-pressure turbine casing lower section 19bHigh-pressure turbine casing upper section 20Exhaust steam casing 20aExhaust steam casing lower section 20bExhaust steam housing upper part DFlow direction Rradial direction

Claims

1. Turbine casing (1) for a turbine, in particular a steam turbine, having a front casing segment (3), configured about a turbine longitudinal axis (2), having a first front casing sub-segment (3a) as well as a second front casing sub-segment (3b), and a rear casing segment (4), configured about the turbine longitudinal axis (2), having a first rear casing sub-segment (4a) as well as a second rear casing sub-segment (4b), wherein the rear casing segment (4) in the flow direction (D) is disposed behind the front casing segment (3) and, while configuring a split cross joint (5), by way of a rear vertical flange (6) of the rear casing segment (4) is fastened to a front vertical flange (7) of the front casing segment (3) on the front casing segment (3), wherein a protrusion (8) that on the front casing segment (3) surrounds the turbine longitudinal axis (2) is configured in a region of the front vertical flange (7), said protrusion (8) extending parallel or at least substantially parallel to the turbine longitudinal axis (2) and in the flow direction (D) protruding beyond the front vertical flange (7), characterized in that an encircling sealing device (10) which seals the protrusion (8) in relation to the rear casing segment (4) is disposed on an external side (9) of the protrusion (8) that faces away from the turbine longitudinal axis (2).

2. Turbine casing (1) according to Claim 1, characterized in that the protrusion (8) is configured so as to be hollow-cylindrical, or substantially hollow-cylindrical, respectively, or hollow-conical, or substantially hollow-conical, respectively.

3. Turbine casing (1) according to Claim 1 or 2, characterized in that the sealing device (10) is disposed and configured in such a manner so as to seal the protrusion (8) in relation to the rear vertical flange (6).

4. Turbine casing (1) according to one of the preceding claims, characterized in that at least one encircling groove (11) is configured in the external side (9) of the protrusion (8), wherein the sealing device (10) has at least one seal ring (12) which has at least one first ring segment (12a) and one second ring segment (12b), wherein the at least one seal ring (12) is at least partially received in the at least one groove (11) and in a sealing manner contacts the rear casing segment (4) in the radial direction (R) in terms of the turbine longitudinal axis (2).

5. Turbine casing (1) according to Claim 4, characterized in that the at least one first ring segment (12a) and the at least one second ring segment (12b) for configuring a gas-tight joint have end regions (13) that at least partially mutually overlap in the circumferential direction.

6. Turbine casing (1) according to Claim 5, characterized in that at least one first end region (13a) of the at least one first ring segment (12a) has at least one recess (14) that is configured in the circumferential direction, and in that at least one second end region (13b) of the at least one second ring segment (12b) has at least one tongue (15) that projects in the circumferential direction, wherein the at least one tongue (15) is configured for engaging in a form-fitting manner in the at least one recess (14).

7. Turbine casing (1) according to one of Claims 4 to 6, characterized in that the at least one seal ring (12) has a ring external diameter which at least in a de-stressed state is larger than a rear casing segment internal diameter of the rear casing segment (4).

8. Turbine casing (1) according to one of the preceding claims, characterized in that a bore (16) which fluidically connects an intermediate space (17) which is configured between the sealing device (10) and the front vertical flange (7) to a second interior region (18b) of the rear casing segment (4) is configured in the rear vertical flange (6), wherein the second interior region (18b) in the flow direction (D) is disposed behind a first interior region (18a) of the rear casing segment (4) that is directly adjacent to the front casing segment (3).

9. Turbine casing (1) according to one of the preceding claims, characterized in that the first front casing sub-segment (3a) is configured as a high-pressure turbine casing lower part (19a) of a high-pressure turbine casing (19) of the turbine casing (1), the second front casing sub-segment (3b) is configured as a high-pressure turbine casing upper part (19b) of the high-pressure turbine casing (19), the first rear casing sub-segment (4a) is configured as an exhaust steam casing lower part (20a) of an exhaust steam casing (20) of the turbine casing (1), and the second rear casing sub-segment (4b) is configured as an exhaust steam casing upper part (20b) of the exhaust steam casing (20).

10. Method for assembling a turbine having a turbine casing according to Claims 5 and 9, comprising the following steps: - inserting the first ring segment (12a) of the seal ring (12) into the groove (11) of the protrusion (8) of the high-pressure turbine casing lower part (19a); - connecting the high-pressure turbine casing lower part (19a) to the exhaust steam casing lower part (20a) so as to form a casing lower part; - inserting interior components of the turbine into the casing lower part; - inserting the second ring segment (12b) of the seal ring (12) into the groove (11) of the protrusion (8) of the high-pressure turbine casing upper part (19b); - connecting the high-pressure turbine casing upper part (19b) to the exhaust steam casing upper part (20b) so as to form a casing upper part; and - depositing the casing upper part onto the casing lower part.