(19) |
|
|
(11) |
EP 2 824 287 B1 |
(12) |
EUROPEAN PATENT SPECIFICATION |
(45) |
Mention of the grant of the patent: |
|
13.05.2020 Bulletin 2020/20 |
(22) |
Date of filing: 08.07.2013 |
|
(51) |
International Patent Classification (IPC):
|
|
(54) |
Pressure casing of a turbomachine
Druckgehäuse einer Turbomaschine
Carter sous pression d'une turbomachine
|
(84) |
Designated Contracting States: |
|
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL
NO PL PT RO RS SE SI SK SM TR |
(43) |
Date of publication of application: |
|
14.01.2015 Bulletin 2015/03 |
(73) |
Proprietor: Ansaldo Energia IP UK Limited |
|
London W1G 9DQ (GB) |
|
(72) |
Inventors: |
|
- Busekros, Armin
8049 Zurich (CH)
- Przybyl, Robert
5303 Wuerenlingen (CH)
- Jeunet-Mancy, Gregory
5430 Wettingen (CH)
|
(74) |
Representative: Bernotti, Andrea et al |
|
Studio Torta S.p.A.
Via Viotti, 9 10121 Torino 10121 Torino (IT) |
(56) |
References cited: :
EP-B1- 1 096 111 CH-A- 385 248 JP-A- S61 200 310
|
WO-A1-03/078799 DE-A1- 3 733 243 US-B1- 6 352 404
|
|
|
|
|
|
|
|
|
Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
|
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to the field of thermal turbomachines, such as stationary
turbines for power generation. It refers to a pressure casing, devided in at least
two casing shells which are removably connected in a pressure-tight manner in a parting
plane by means of a flange.
BACKGROUND ART
[0002] Conventional bolted flange joints for pressure casings of thermal turbomachines,
as are reproduced in an example in Fig. 1, or of other installations with similar
requirements, have a plurality of disadvantages which are to be eliminated by the
present invention. In the known pressure casing 10 from Fig. 1, two casing shells
10a and 10b are bolted together in a pressure-tight manner in a parting plane 11 via
a flange 12. This is carried out by means of threaded bolts 14 which, by means of
a through-hole 13 in the upper casing shell 10a, are screwed into a threaded hole
16 in the lower casing shell 10b and in this case supported by a nut 15 on a shoulder
at the flange of the upper shell 10a. The casing shells 10a, 10b surround a flow channel
18 for a working medium, such as air, steam or hot combustion gases.
[0003] The following disadvantages result from this arrangement:
During the warm-up phase of the pressure casing 10, during a cold start, the casing
material which surrounds the threaded bolts 14 heats up more quickly than the shaft
of the threaded bolts 14 within the through-hole 13, which, on account of the different
thermal expansion of the bolts and the casing 10, can lead to an overload and plastic
elongation of the threaded bolts 14. The elongated bolts 14 can relax and the bolting
forces diminish with subsequent local leakages during operation of the machine.
[0004] To avoid the above said disadvantage the state of the practice tends to oversize
the connecting bolts. But larger bolts effect other negative consequences.
[0005] At heavily loaded places, it can happen that the inner-lying sealing is opened as
a result of stresses in the casing wall, whereas the outer-lying support lip is more
heavily loaded because the torque created by the wall and the bolt forces has to be
compensated by means of a higher counter-force on the outer support lip. Consequently,
the necessary pressure upon the sealing cannot be maintained any longer, in fact not
even with larger bolts because with bolt diameters becoming larger the axis in which
the bolt force acts is further away from the inner sealing lip than in the case of
smaller bolts so that the leak-tightness of the sealing lip in actual fact is not
improved.
[0006] The published patent application
DE 10225260 A1 discloses a casing for an axial turbomachine with an upper half shell and a lower
half shell connected in a horizontal parting plane by means of a flange. The connecting
bolts extend through a through hole in the upper half shell and are being placed in
a thread hole of the lower half shell, whereby an annular space is formed between
the outer surface of the bolt and the inner surface of the through hole. In an upper
part of this annular space a thermally insulated sleeve is located. It is the aim
of this solution to minimize the heat transfer between the connecting bolts and the
ambient fluid. This solution cannot solve the above-mentioned problems during the
warm-up phase.
[0007] Patent application
WO 2003078799 A1 discloses an arrangement for cooling or heating of the flange bolts in a turbine
casing. A bolt comprises one or more bore holes extending axially through the bolt.
Said bore holes are optionally charged either with a heating or with a cooling medium.
The cooling or heating medium flows through the at least one bore hole thereby cooling
or heating the bolt. The stabilized temperature regime of the bolt effects a damping
of bolt relaxation and ensures that the bolting forces remain stable during steady-state
operation and during transient operations. Another disclosed embodiment teaches to
equip the bolts with additional radial bore holes extending from the axial bore hole
to the annular space between the bolt and the flange boring. This embodiment effects
an increase of heat transfer and forces the cooling or heating gradient. It is a disadvantage
of this solution that the plurality of bore holes weakens the mechanical integrity
of the bolts. This weakening of integrity has to be compensated by an undesirably
larger dimensioning of the bolts.
[0008] JP S61 200310 A describes a pressure casing cpmprising a flange sealingly pressed together by threaded
bolts. The connecting bolts extend through a through hole in the upper half shell
and are being placed in a thread hole of the lower half shell, whereby an annular
space is formed between the outer surface of the bolt and the inner surface of the
through hole. In for example the upper end of this annular space a cooling or heating
fluid is introduced and exits the annular space at the lower end.
[0009] Quite another arrangement is disclosed in the document
EP 1096111 B1, directed to a cooling structure for the flange of a steam turbine casing. The aim
to prevent steam leakage caused by a drop of the fastening force of the flange bolts
is achieved by cooling the flange. The upper and lower half shell of the casing are
covered with a heat insulating material and a number of cooling pipes contacts the
peripheral end surfaces of the flanges. By convective heat transfer the flange is
cooled. The bolts are cooled indirectly via the flange. This cooling arrangement effects
primarily a cooling of the peripheral end surface of the flange. The cooling effect
to the bolts is low, because the working steam inside the steam turbine warms the
flange. A significant cooling of the bolts would require an extensive heat removal
from the flange.
This cooling arrangement is only applicable to the outer casing of a turbine, but
it is not suitable for inner casings. The above-referred problems during a cold start
are not solved by this solution.
[0010] US 6 352 404 B1 discloses a casing having shells joined at a parting plane and proivided with respective
flanges sealingly clamped by bolts extending trough the flanges prependicularly to
the parting plane. Channels for a heat transfer fluid for transferring heat to/from
the bolts are arranged in the parting plane of the flanges.
[0011] From
DE 37 33 243 A1 a hollwo bolt is known that is elongated by filling it with a pressurized fluid to
a certain extend. Once the ciorrect elongation has been achiecved a nut is fastened
and the pressure of the fluid is released.
SUMMARY OF THE INVENTION
[0012] It is therefore an object of the invention to disclose a pressure casing for a turbomachine
which avoids significant thermal gradients within the flanged joint, i.e. between
the flange and the connecting bolts, to improve the stabilization of the bolting forces
throughout all operating conditions.
[0013] The object is achieved by a pressure casing as set forth in claim 1. The invention
is based on a pressure casing which comprises at least two casing shells which can
be connected in a pressure-tight manner in a parting plane by means of a flange, wherein
the casing shells are pressed together with sealing effect in the parting plane in
the region of the flange by means of at least one threaded bolt which extends through
the flange perpendicularly to the parting plane. The invention is distinguished by
the fact that the at least one threaded bolt is charged by a heat transfer medium,
i.e. based on operational requirement either a heating or a cooling medium, and this
heat transfer medium is supplied or discharged via passages and at least a portion
of the passages (22, 23, 24) for the heat transfer medium are arranged in the parting
plane (11) of the flange (12) . This measure supports an equalization of the temperatures
of the flange and the connecting bolts, thereby avoiding overload of the bolts during
start up phases and diminishment of bolting forces during shutdown.
[0014] According to a preferred embodiment the heat transfer medium charges the bolt in
the annular space between the shaft of the bolt and the inner lateral surface of the
through hole.
[0015] According to a further embodiment the annular space between the shaft of the bolt
and the inner lateral surface of the through hole is sealed in a gas tight manner
on its both longitudinal ends, wherein at the one end a feed hole for the heat transfer
medium leads into the annular space and at the opposite end an outlet hole for the
heat transfer medium branches off.
[0016] One development of the invention is characterized in that the heat transfer medium
is air.
[0017] In particular, the heat transfer medium is compressor air.
[0018] According to an alternative embodiment the heat transfer medium is steam, particularly
branched off steam from a steam turbine.
BRIEF EXPLANATION OF THE FIGURES
[0019] The invention shall subsequently be explained in more detail based on exemplary embodiments
in conjunction with the drawing. In the drawing
Fig. 1 shows in a sectional view a flanged joint of a pressure casing according to
the state of the art;
Fig. 2 shows in a sectional top view a flanged joint of a pressure casing according
to the invention;
Fig. 3 shows an exemplary use of a pressure casing in a compressor.
WAYS OF IMPLEMENTING THE INVENTION
[0020] The above-described disadvantages of the conventional pressure casing with a flanged
joint are eliminated by a construction as is schematically reproduced in Fig. 2 in
an exemplary embodiment of the invention. The pressure casing 10 comprises, as shown
in Fig. 1, an upper casing shell 10a and a lower casing shell 10b which abut on a
flange 12 in a parting plane 11 and are bolted to each other there in a pressure-tight
manner by threaded bolts 14. For each of the threaded bolts 14 provision is made in
the upper casing shell 10a in the region of the flange 12 for a through-hole 13 with
an inner diameter larger than the outer diameter of the bolt 14 to provide an annular
space 17, and provision is made in the lateral surface of this through hole 13 for
a supply and discharge of either a heating or a cooling medium. On both sides the
annular space 17 is sealed in a gas tight manner.
[0021] During operation, based on operational requirements, either a cooling or a heating
medium is supplied from a source 20 to the annular space 17 via at least one feed
hole 22. The feed hole 22 opens into the space 17 at one of its longitudinal ends.
From there the heat transfer medium flows around the shaft of the bolt 14 towards
the opposite end of space 17. Via outlet hole 23 the heat transfer medium leaves the
annular space 17 to be discharged in a volume 21 with a lower pressure compared to
the pressure of the source 20. This volume 21 may be a suitable cavity inside or outside
of the casing 10. Outlet hole 23 again extends through the flange 12 in a way to intensify
the heat transfer between the heat transfer medium and the flange 12.
[0022] The heat transfer medium is supplied from a fluid source 20. Source 20 for the heat
transfer medium is an air plenum of a gas turbine. From this source 20 the feed hole
22 is passed through the flange 12 in a way to allow heat transfer between the flange
12 and the heat transfer medium. The feed hole 22 may have a circular or a non-circular,
particularly a rectangular cross section. The feed hole 22 may comprise a section
with an enlargement of cross section to combine feed holes 22 from different sources
20 or to branch feed holes 22 to different through holes 13.
[0023] According to an embodiment of the invention the feed holes 22 or the outlet holes
23 are arranged in the parting plane 11. By this arrangement curved or even serpentine
holes 22, 23 can be manufactured easily, e.g. by milling a groove in the contact surfaces
of the flange 12.
[0024] Fig. 2 schematically shows alternative embodiments to realize this invention. According
to a first embodiment, illustrated on the left side of Fig. 2, from a plenum 20 a
mass flow of air is discharged into feed line 22. Feed line 22 passes an area of the
flange 12 and ends in the through hole 13' of a first threaded bolt 14'. From this
first through hole 13' the heat transfer medium passes through a connecting hole 24
inside of flange 12 to a second bolt 14" in a second through hole 13" etc. Finally,
the exhaust heat transfer medium 26 is discharged via outlet hole 23 into the flow
channel 18.
[0025] According to a second embodiment, as illustrated on the right side of Fig. 2, the
flow channel 18 of the turbomachine serves as source of the heat transfer medium.
A partial flow of the working medium is branched off from the flow channel 18 and
fed into the feed line 22. From feed line 22 the heat transfer medium is passed through
the flange 12 to one or more connecting bolts 14 and is finally discharged via the
outlet hole 23 into a cavity 21 inside or outside of the outer casing of the turbomachine.
[0026] The embodiment of Fig. 3 refers to an example which is not part of the invention,
especially applicable to a compressor casing. The lower and the upper shell of the
compressor are equipped with a flange 12. Threaded bolts 14, extending through the
through holes 13 in the upper shell 10a, join the two half shells in a gas tight manner
by interaction with a thread in the lower half shell. The flow channel 18 of the compressor
comprises a number of compressor stages. A feed line 22 branches off from the flow
channel 18 at a defined vane row (i) (reference 28). The feed line 22 extends through
the flange 12 and ends inside a first through hole 13' at its longitudinal end. At
the opposite longitudinal end a connecting hole 24 connects this first through hole
13' with a second through hole 13", whereby this second hole 13" is located upstream
against the flow direction 19 of the working medium in the flow channel 18. From the
second through hole 13" an outlet hole 23 extends through the flange 12 and ends in
the flow channel 18 at a vane row 29 upstream of the above-mentioned vane row (i)
(reference 29), i.e. in an upstream compressor section with a lower pressure. During
transient operating phases a partial flow 25 of the compressor air stream is branched
off from the flow channel 18 into the feed hole 22. Under convective heat transfer
the air stream 25 passes the flange 12, enters the annular space 17' between the through
hole 13' and the shaft of the first bolt 14' at its e.g. upper longitudinal end. The
air flows along the shaft of bolt 14' under convective heat transfer. At the opposite
longitudinal end the air flow 27 enters the connecting hole 24, passes again the flange
12 and reaches the through hole 13" of the second bolt 14", flows along the shaft
of the second bolt 14". Via the outlet hole 23 the exhausted air 26 is directed back
into the flow channel 18 at a vane row 29, located upstream of the vane row 28.
[0027] This embodiment of a device for flange and bolts temperature adjustment uses the
pressure difference between two different compressor stages.
[0028] As a result of this type of construction according to the invention the following
advantages are achieved:
- The heat transfer medium flowing through the annular space 17 between the through
hole 13 and will quicker warm up the bolt 14 during start-up, compared to used conventional
solutions;
- The heat transfer medium flowing through the annular space 17 between the through
hole 13 and will quicker cool down the bolt 14 during shut down;
- The temperature difference between the flange 12 and the connecting bolts 14 during
transient operating modes are significantly reduced;
- The risk of overload of the connecting bolts 14 during start-up phases is eliminated;
- The pretension of the bolts during shut down is maintained.
LIST OF DESIGNATIONS
[0029]
- 10
- casing
- 10a
- upper casing shell
- 10b
- lower casing shell
- 11
- parting plane
- 12
- flange
- 13
- through hole
- 14
- threaded bolt
- 15
- Nut
- 16
- threaded hole
- 17
- annular space
- 18
- flow channel
- 19
- flow direction of the working medium in channel
- 20
- source of the heat transfer medium, space of higher pressure
- 21
- volume for exhausted heat transfer medium, cavity of lower pressure
- 22
- feed hole from source 20 to the bolt 14
- 23
- outlet hole from the bolt 14 to volume 21
- 24
- connecting hole between bolts 14', 14"...
- 25
- fresh heat transfer medium
- 26
- exhausted heat transfer medium
- 27
- partially used heat transfer medium
- 28
- compressor stage
- 29
- compressor stage
- 30
- plug
1. Pressure casing of a turbomachine, which comprises at least two casing shells (10a,
10b) which are connected in a pressure-tight manner in a parting plane (11) by means
of a flange (12), wherein the casing shells (10a, 10b) are pressed together with sealing
effect in the parting plane (11) in the region of the flange (12) by means of at least
one threaded bolt (14) which extends through a through hole (13) in the flange (12)
perpendicularly to the parting plane (11), wherein the at least one threaded bolt
(14) is charged by a heat transfer medium, wherein at least one of feed holes (22)
or outlet holes (23) for the heat transfer medium are arranged in the parting plane
(11) of the flange (12),
characterized in that:
the feed holes (22) receive the heat transfer medium from a plenum and the outlet
holes (23) discharge into a flow channel (18) for a working medium inside the pressure
casing; or
the feed holes (22) receive the heat transfer medium from the flow channel (18) and
the outlet holes (23) discharge into a cavity (21) outside the pressure casing.
2. Pressure casing as claimed in claim 1, characterized in that one or more feed holes (22) for the heat transfer medium start at a source (20) for
the heat transfer medium, extend through the flange (12) and end in a lateral surface
of the through hole (13).
3. Pressure casing as claimed in claim 1 or 2, characterized in that one or more outlet holes (23) for the heat transfer medium start at the through hole
(13), extend through the flange (12) and end in a volume (21) of a relatively low
pressure compared to the pressure of the source (20).
4. Pressure casing as claimed in one of the claims 1 to 3, characterized in that an annular space (17) is provided between the inner lateral surface of the through
hole (13) and the shaft of the threaded bolt (14), this annular space (17) is sealed
in a tight manner on its both longitudinal ends and this annular space (17) is charged
by the heat transfer medium.
5. Pressure casing as claimed in claim 4, characterized in that at least one of the feed holes (22) or the outlet holes (23) are open to the annular
space (17).
6. Pressure casing as claimed in claim 5, characterized in that the at least one feed hole (22) and the at least one outlet hole (23) lead to opposite
ends of the annular space (17).
7. Pressure casing as claimed in one of the claims 1 to 6, characterized in that at least one of feed holes (22) or outlet holes (23) for the heat transfer medium
are passed through the flange (12).
8. Pressure casing as claimed in one of the claims 1 to 7, characterized in that heat transfer medium is air.
9. Pressure casing as claimed in one of the claims 1 to 7, characterized in that the heat transfer medium is steam.
10. Pressure casing as claimed in one of the claims 1 to 9, characterized in that the turbomachine is a compressor.
11. Pressure casing as claimed in one of claims 1 to 8, characterized in that the casing is an inner carrier of a gas turbine.
1. Druckgehäuse einer Turbomaschine, das mindestens zwei Gehäuseschalen (10a, 10b) aufweist,
die in druckdichter Weise in einer Trennebene (11) mittels eines Flansches (12) verbunden
sind, wobei die Gehäuseschalen (10a, 10b) in der Trennebene (11) im Bereich des Flansches
(12) mittels mindestens eines Gewindebolzens (14), der durch eine Durchgangsbohrung
(13) in dem Flansch (12) senkrecht zu der Trennebene (11) verläuft, mit abdichtender
Wirkung zusammengepresst werden, wobei der mindestens eine Gewindebolzen (14) mit
einem Wärmeübertragungsmedium beschickt wird, wobei mindestens eines der Zuführlöcher
(22) oder Auslasslöcher (23) für das Wärmeübertragungsmedium in der Trennebene (11)
des Flansches (12) angeordnet ist,
dadurch gekennzeichnet, dass:
die Zuführlöcher (22) das Wärmeübertragungsmedium aus einem Vorrat erhalten und die
Auslasslöcher (23) in einen Durchflusskanal (18) für ein Arbeitsmedium innerhalb des
Druckgehäuses ableiten; oder
die Zuführlöcher (22) das Wärmeübertragungsmedium aus dem Durchflusskanal (18) erhalten
und die Auslasslöcher (23) in einen Hohlraum (21) außerhalb des Druckgehäuses ableiten.
2. Druckgehäuse nach Anspruch 1, dadurch gekennzeichnet, dass ein oder mehrere Zuführlöcher (22) für das Wärmeübertragungsmedium an einer Quelle
(20) für das Wärmeübertragungsmedium beginnen, durch den Flansch (12) verlaufen und
in einer seitlichen Oberfläche des Durchgangslochs (13) enden.
3. Druckgehäuse nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass ein oder mehrere Auslasslöcher (23) für das Wärmeübertragungsmedium an dem Durchgangsloch
(13) beginnen, durch den Flansch (12) verlaufen und in einem Volumen (21) mit einem
im Vergleich zu dem Druck der Quelle (20) relativ niedrigem Druck enden.
4. Druckgehäuse nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass ein ringförmige Raum (17) zwischen der inneren Seitenfläche des Durchgangslochs (13)
und dem Schaft des Gewindebolzens (14) vorgesehen ist, dieser ringförmige Raum (17)
in dichter Weise an seinen beiden Längsenden abgedichtet ist und dieser ringförmige
Raum (17) mit dem Wärmeübertragungsmedium beschickt wird.
5. Druckgehäuse nach Anspruch 4, dadurch gekennzeichnet, dass mindestens eines der Zuführlöcher (22) oder der Auslasslöcher (23) sich in den ringförmigen
Raum (17) öffnet.
6. Druckgehäuse nach Anspruch 5, dadurch gekennzeichnet, dass das mindestens eine Zuführloch (22) und das mindestens eine Auslassloch (23) zu entgegengesetzten
Enden des ringförmigen Raums (17) führen.
7. Druckgehäuse nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet das mindestens eines der Zuführlöcher (22) oder Auslasslöcher (23) für das Wärmeübertragungsmedium
durch den Flansch (12) geführt ist.
8. Druckgehäuse nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass das Wärmeübertragungsmedium Luft ist.
9. Druckgehäuse nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass das Wärmeübertragungsmedium Dampf ist.
10. Druckgehäuse nach einem der Ansprüche 1 bis 9, dadurch gekennzeichnet, dass die Turbomaschine ein Verdichter ist.
11. Druckgehäuse nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, dass das Gehäuse ein innerer Träger einer Gasturbine ist.
1. Enveloppe sous pression d'une turbomachine, qui comprend au moins deux chemises d'enveloppe
(10a, 10b) qui sont connectées d'une façon étanche à la pression dans un plan de séparation
(11) au moyen d'une bride (12),
où les chemises d'enveloppe (10a, 10b) sont pressées ensemble avec un effet d'étanchéité
dans le plan de séparation (11) dans la région de la bride (12) à l'aide d'un boulon
fileté (14) au moins qui s'étend à travers un trou traversant (13) dans la bride (12)
perpendiculairement au plan de séparation (11),
où l'un au moins des boulons filetés (14) est mis sous pression par un milieu de transfert
de la chaleur, où l'un au moins des trous d'entrée (22) ou des trous de sortie (23)
du milieu de transfert de la chaleur, est agencé dans le plan de séparation (11) de
la bride (12),
caractérisée en ce que :
les trous d'entrée (22) reçoivent le milieu de transfert de la chaleur en provenance
d'un plénum, et les trous de sortie (23) l'évacuent dans un canal de flux (18) d'un
milieu de travail à l'intérieur de l'enveloppe sous pression ; ou
les trous d'entrée (22) reçoivent le milieu de transfert de la chaleur en provenance
du canal de flux (18), et les trous de sortie (23) l'évacuent dans une cavité (21)
à l'extérieur de l'enveloppe sous pression.
2. Enveloppe sous pression selon la revendication 1,
caractérisée en ce qu'un ou plusieurs trous d'entrée (22) du milieu de transfert de la chaleur débutent
au niveau d'une source (20) du milieu de transfert de la chaleur, s'étendent à travers
la bride (12), et se terminent dans une surface latérale du trou traversant (13).
3. Enveloppe sous pression selon la revendication 1 ou 2,
caractérisée en ce qu'un ou plusieurs trous de sortie (23) du milieu de transfert de la chaleur débutent
au niveau du trou traversant (13), s'étendent à travers la bride (12), et se terminent
dans un volume (21) à pression relativement basse par rapport à la pression de la
source (20).
4. Enveloppe sous pression selon l'une quelconque des revendications 1 à 3,
caractérisée en ce qu'un espace annulaire (17) est prévu entre la surface latérale intérieure du trou traversant
(13), et la tige du boulon fileté (14), cet espace annulaire (17) est scellé d'une
façon étanche sur ses deux extrémités longitudinales, et cet espace annulaire (17)
est mis sous pression par le milieu de transfert de la chaleur.
5. Enveloppe sous pression selon la revendication 4,
caractérisée en ce que l'un au moins des trous d'entrée (22) ou des trous de sortie (23), est ouvert dans
l'espace annulaire (17).
6. Enveloppe sous pression selon la revendication 5,
caractérisée en ce que l'un au moins des trous d'entrée (22) et l'un au moins des trous de débouché (23),
conduisent aux extrémités opposées de l'espace annulaire (17).
7. Enveloppe sous pression selon l'une quelconque des revendications 1 à 6,
caractérisée en ce que l'un au moins des trous d'entrée (22) ou des trous de sortie (23) du milieu de transfert
de la chaleur, passe à travers la bride (12).
8. Enveloppe sous pression selon l'une quelconque des revendications 1 à 7, caractérisée en ce que le milieu de transfert de la chaleur est l'air.
9. Enveloppe sous pression selon l'une quelconque des revendications 1 à 7, caractérisée en ce que le milieu de transfert de la chaleur est de la vapeur.
10. Enveloppe sous pression selon l'une quelconque des revendications 1 à 9, caractérisée en ce que la turbomachine est un compresseur.
11. Enveloppe sous pression selon l'une quelconque des revendications 1 à 8, caractérisée en ce que l'enveloppe est un support intérieur d'une turbine à gaz.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description