USOO685.

7847B2

(12) United States Patent (10) Patent No.: US 6,857,847 B2

Iacopetti (45) Date of Patent: Feb. 22, 2005

(54) SIMPLIFIED SUPPORT DEVICE FOR (56) References Cited

NOZZLES OF A GAS TURBINE STAGE U.S. PATENT DOCUMENTS
(75) Inventor: Piero Iacopetti, Pistoria (IT) 3,275,294 A 9/1966 Allen et al. ................. 415/115
5,215,435 A * 6/1993 Webb et al. ...... ... 415/173.7
(73) Assignee: Nuovo Pignone Holding S.p.A., 5,358,374. A * 10/1994 Correia et al. .............. 415/115
Florence (IT) 6,065,928 A * 5/2000 Rieck et al. ...... ... 415A115
6,398.488 B1 * 6/2002 Solda et al. ................ 415/115
(*) Notice: Subject to any disclaimer, the term of this FOREIGN PATENT DOCUMENTS
patent is extended or adjusted under 35 GB 2127906 A 4/1984 .............. 415/173.7
U.S.C. 154(b) by 0 days.
* cited by examiner
(21) Appl. No.: 10/452,900 Primary Examiner-Christopher Verdier
(74) Attorney, Agent, or Firm Nixon & Vanderhye
(22) Filed: Jun. 3, 2003 (57) ABSTRACT
(65) Prior Publication Data
A simplified support device (110) for nozzles (112) of a gas
US 2004/0033132 A1 Feb. 19, 2004 turbine stage, of the type in which the support device (110)
(30) Foreign Application Priority Data is interposed in a rotor of the gas turbine, between an
upstream blading disc (122) and a downstream blading disc
Jun. 5, 2002 (IT) ..................................... MI2OO2A1219 (124) of the nozzles (112), and is provided with honeycomb
(51) Int. Cl. ................................................. FO1D 11/02 type alveolar seals (120); the nozzles (112) of the gas turbine
(52) U.S. Cl. ................. 415/115; 41.5/173.7; 41.5/1744; Stage comprise an annular body which is divided into nozzle
415/174.5 segments (112) and the honeycomb-type alveolar seals (120)
(58) Field of Search ........................... 415/173.7, 1744,
are anchored directly to these nozzle segments (112).
415/174.5, 230, 115, 116 1 Claim, 2 Drawing Sheets
U.S. Patent Feb. 22, 2005 Sheet 1 of 2 US 6,857,847 B2

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PRIOR ART
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U.S. Patent Feb. 22, 2005 Sheet 2 of 2 US 6,857,847 B2

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 US 6,857,847 B2
1 2
SIMPLIFIED SUPPORT DEVICE FOR In particular, the area of internal constraint between the
NOZZLES OF A GAS TURBINE STAGE nozzle Segments and the annular Support is one of these
CS.
The present invention relates to a simplified Support On the gas turbines constructed hitherto, the problem has
device for nozzles of a gas turbine Stage. been Solved with application below the nozzle of a mechani
AS is known, gas turbines are machines which consist of cal System comprising a diaphragm-type Segment and a
a compressor and of a turbine with one or more Stages, honeycomb-type alveolar Seal which is interposed in the
wherein these components are connected to one another by rotor, in order to Separate an upstream blading disc from a
a rotary shaft, and wherein a combustion chamber is pro downstream blading disc of the nozzle itself.
vided between the compressor and the turbine. In this known configuration, each nozzle Segment, which
In these machines, the compressor is fed with air which is connected on the exterior to the body by means of
is obtained from the external environment, in order to Segments known as Shrouds, Supports in its interior a
preSSurise it.
The compressed air passes through a Series of pre-mixing diaphragm-type Segment which in turn contains in its inte
chambers, which end in a converging portion, into each of rior the honeycomb-type alveolar Seal.
which an injector feeds fuel which is mixed with the air in 15 The diaphragm-type Segments are connected to the
order to form a fuel-air mixture to be burned. nozzle Segments by means of clasps and grooves corre
Into the combustion chamber there is admitted the fuel, spondingly provided on the items. The Sealing in relation to
which is ignited by means of corresponding Spark plugs in the rotor blading discs is obtained by means of foils which
order to give rise to the combustion, which is designed to are embedded in the diaphragm-type Segments.
give rise to an increase of temperature and pressure, and thus The blading disc cooling System, when it exists, contains
to enthalpy of the gas. in its final Section the passage for the air in holes provided
Simultaneously, the compressor provides compressed air, in the diaphragm-type Segments.
which is made to pass both through the burners, and through The object of the present invention is to make improve
the liners of the combustion chamber, Such that the said ments to the known art previously described, and in par
compressed air is available to feed the combustion. 25 ticular that of providing a simplified Support device for
Subsequently, via corresponding pipes, the high nozzles of a gas turbine Stage, which permits a significant
temperature, high-pressure gas reaches the different Stages reduction of the costs.
of the turbine, which transforms the enthalpy of the gas into Another object of the present invention is to provide a
mechanical energy available to a user. Simplified Support device for nozzles of a gas turbine Stage,
For example, in two-stage turbines, the gas is processed which permits improved cooling of the rotor blading discs.
in the first turbine Stage in very high temperature and Another object of the present invention is to provide a
pressure conditions, and undergoes initial expansion there; simplified support device for nozzles of a gas turbine stage,
whereas in the Second Stage of the turbine it undergoes a which is particularly reliable and functional.
Second expansion, in temperature and preSSure conditions This object and others according to the present invention
which are lower than in the previous case. 35 are achieved by providing a simplified Support device for
It is also known that, in order to obtain the maximum nozzles of a gas turbine Stage, as described in claim 1.
performance from a specific gas turbine, it is necessary for Further characteristics are described in the Successive
the temperature of the gas to be as high as possible; however, claims.
the maximum temperature values which can be obtained in The characteristics and advantages of a simplified Sup
use of the turbine are limited by the strength of the materials 40 port device for nozzles of a gas turbine Stage according to
used. the present invention will become clearer and more apparent
A brief description is now provided of the system of from the following description, provided by way of non
Stator nozzles and rotor blades of the different Stages of a gas limiting example, with reference to the attached Schematic
turbine according to the known art. drawings, in which:
The first-stage nozzle is used to present the flow of burnt 45 FIG. 1 is a croSS-Section of a Support device for nozzles
gases in Suitable conditions at the intake of the first-stage of a gas turbine Stage, as known according to the existing art;
rOtOr. and
The nozzle assembly for the Second Stage of a gas turbine FIG. 2 shows a croSS-Section of a simplified Support
consists of an annular body, which in turn can be divided device for nozzles of a gas turbine Stage, according to the
into nozzle Segments, each Segment generally consisting of 50 present invention.
nozzles which are defined or determined by foils with a FIG. 1 shows a Support device, which is indicated as 10
corresponding wing-type profile. as a whole, for nozzles 12 of a gas turbine Stage, and is
This nozzle assembly for the Second Stage is connected interposed in a rotor of the gas turbine itself in order to
on the exterior to the turbine body and on the interior to a Separate an upstream blading disc 22 from a downstream
corresponding annular Support. 55 blading disc 24 of the nozzle 12 itself.
In this respect, it should be noted that the Stators are The nozzles 12 of a gas turbine Stage comprise an annular
Subjected to high-pressure loads owing to the reduction of body, which in turn can be divided into nozzle Segments 12.
preSSure between the intake and outlet of the nozzles. Each nozzle Segment 12, which is connected on the
In addition, the Stators are Subjected to high temperature exterior to a gas turbine body 14 by means of Segments
gradients, owing to the flow of hot gases obtained from the 60 known as Shrouds 16, is Supported in its interior by the
combustion chamber and from the preceding Stage, and to support device 10.
the flows of cold air which are introduced into the turbine in This Support device 10 comprises a diaphragm-type
order to cool the parts which are Subjected to the greatest Segment 18, which is connected to the nozzle Segments 12
StreSS from the thermal and mechanical points of view. by means of clasps and grooves which are arranged corre
Another problem which is particularly significant in the 65 spondingly on the items, and a honeycomb-type alveolar
art of gas turbines is that of Separation of areas with different Seal 20, which is provided inside the diaphragm-type Seg
temperatures and pressures. ment 18.
 US 6,857,847 B2
3 4
The sealing relative to the rotor blading discs 22 and 24 also makes apparent the corresponding advantages, which, it
is obtained by means of foils which are embedded in the will be remembered, include:
diaphragm-type Segments 18. Simple and reliable usage;
In the diaphragm-type Segments 18 there can also be Substantial reduction in the production costs,
provided cooling holes 26 for air which cools the upstream facilitated maintenance.
22 and downstream 24 blading discs.
FIG. 2 illustrates a simplified Support device according to Finally, it is apparent that many modifications and
the present invention, which is indicated as a whole as 110, variations, all of which come within the scope of the
for nozzles 112 of a gas turbine Stage, wherein the compo invention, can be made to the Simplified Support device thus
nents which are the same as?equivalent to those illustrated in designed for nozzles of a gas turbine Stage, in addition, all
FIG. 1 of the known art have the same reference numbers the details can be replaced by technically equivalent ele
increased by 100. ments. In practice, any materials, forms and dimensions can
In the example illustrated, according to the present be used, according to the technical requirements.
invention, the simplified support device 110 comprises Sub The scope of protection of the invention is thus delimited
Stantially an annular honeycomb-type alveolar Seal 120. 15 by the attached claims.
This alveolar seal 120 is anchored directly to a lower What is claimed:
platform 130 of the nozzle segments 112, without including 1. A simplified Support device for nozzles of a gas turbine
diaphragm-type Segments. having a rotor Spaced radially from the Surrounding nozzles,
In the nozzles 112, and in particular in the vicinity of the Said Support device being interposed between the rotor and
lower platform 130 of the nozzle segment 112, there can also the nozzles and between an upstream blading disc and a
be provided cooling holes 126 for air which cools the downstream blading disc, Said Support device being pro
upstream 122 and downstream 124 blading discs. Vided with honeycomb alveolar Seals, Said nozzles compris
The solution with the simplified support device 110, ing an annular body divided into nozzle Segments, Said
which for example is used for the nozzles 112 of the second honeycomb alveolar Seals being anchored directly to a lower
Stage of a low-pressure gas turbine, is undoubtedly more 25 platform of Said nozzle Segments by axially reduced portions
economical than that with the Support device 10 according of the nozzle Segments, Said axially reduced portions having
to the known art, and Simultaneously the efficiency of cooling holes for conveying cooling air Supplied through the
Washing of the blading discS 122 and 124 is improved, Since nozzle Segments in axially forward and aft directions for
the losses caused by blow-by are decreased. cooling Said upstream blading discS and downstream blading
The description provided makes apparent the character discS, respectively.
istics of the simplified support device which is the subject of
the present invention, for nozzles of a gas turbine stage, and
 UNITED STATES PATENT AND TRADEMARK OFFICE
CERTIFICATE OF CORRECTION

PATENT NO. : 6,857,847 B2 Page 1 of 1

DATED : February 22, 2005
INVENTOR(S) : Iacopetti, P.

It is certified that error appears in the above-identified patent and that said Letters Patent is
hereby corrected as shown below:

Column 2
Line 34, the paragraph beginning with "This object and others..." should be deleted.

Signed and Sealed this

Fifth Day of July, 2005

WDJ
JON W. DUDAS
Director of the United States Patent and Trademark Office