WO2014108199A1

WO2014108199A1 - Method for producing gas turbines and method for operating gas turbine systems

Info

Publication number: WO2014108199A1
Application number: PCT/EP2013/050452
Authority: WO
Inventors: Axel Kaiser; Werner Stamm
Original assignee: Siemens Aktiengesellschaft
Priority date: 2013-01-11
Filing date: 2013-01-11
Publication date: 2014-07-17
Also published as: EP2904129A1

Abstract

The use of different ceramic layers allows different configurations of gas turbines to be produced, the configurations being subsequently optimized for their use in either base load operation or peak load operation.

Description

Method for producing gas turbines and method for operating gas turbine installations

The invention relates to a method for the production of gas turbines, which are designed to be flexible and methods for operating gas turbines.

Gas turbines can be operated during power generation in base load operation or in particular in peak load operation.

The requirements for the respective conditions are different. An optimized configuration of the gas turbine that satisfies both on ^¬ requirements would always be a compromise.

It is therefore an object of the invention to solve this problem. The object is achieved by a method for producing gas turbines according to claim 1 and a method according to claim 33.

In the dependent claims further advantageous measures are listed, which are combined with each other Kings ^¬ nen to obtain further advantages:

These further advantages are achieved in that - for the second gas turbine only the metallic Haftvermitt ^¬ lerschicht is changed

- For the second gas turbine, the metallic adhesion promoter ^¬ layer and the ceramic layer are changed to it

- A two-layer ceramic thermal barrier coating (13) is removed from the first turbine blades and / or

a single-layer thermal barrier coating {1 '') is applied as a second ceramic thermal barrier coating on the second or new second turbine blades - in which the single-layer ceramic thermal barrier coating {1 '') is produced with a porosity of 18% ± 4%,

- In which a single-layer thermal barrier coating (7) is removed from the first turbine blades and / or

applying a two-layer thermal barrier coating (13 ') as a second ceramic thermal barrier coating to the second or new second turbine blades;

in particular a two-layered thermal barrier coating (13 ')

in which the porosity of the second ceramic thermal barrier coating (7 ', 7' ', 13') of the second or the new second turbine blades is increased compared to the porosity of the thermal barrier coating of the first turbine blades,

- In which the porosity of the second ceramic thermal barrier coating (7 ', 7' ', 13) of the second or the new second turbine blades with respect to the porosity of the thermal barrier coating of the first turbine blades is lowered

- in which a thinner ceramic thermal barrier coating (7) replaces the first ceramic thermal barrier layer with a thicker ceramic thermal barrier coating (7 ', 13') as a second ceramic thermal barrier coating of the second or new two ^¬ th turbine blades,

where the difference in thickness is at least + 50μη -

- a thicker ceramic thermal barrier coating as the first Kerami ^¬ specific heat-insulating layer is replaced by a thinner Kerami ^¬ specific thermal insulation layer as a second ceramic thermal barrier layer of the second or the new second turbine blades, wherein the difference in thickness is at least -50μη

- The two-layer thermal barrier coating (13 ') with a lowermost ceramic layer {!' '') is produced with a porosity of 12% ± 4% and with an outer ceramic layer (10 ') with a porosity of 18% ± 4%,

wherein the absolute difference in the porosity of the ceramic j ^¬ rule layers {! ''',10') at least 2%,

especially 4%,

more particularly, it is at most 4%,

- The two-layer thermal barrier coating (13) with a lowermost ceramic layer {! ''') with a porosity of 18% ± 4% and with an outer ceramic layer (10') with an equal Porosity of 18% ± 4% is generated,

a two-layered thermal barrier coating (13 ') having a lowermost ceramic layer {' '' ') with a porosity of 18% ± 4% and with an outer ceramic layer (10') having a porosity of 25% ± 4% is produced,

especially 4%,

more particularly, it is at most 4%,

- The lower layer {! '' ') of the two-layer thermal barrier coating (13) is made thinner, in particular at least 20% thinner than the upper layer (10'),

in particular wherein the lower layer {! ''') has a thickness of 75ym the two-layer thermal barrier coating (13) to 150ym, more in particular, the total thickness of the two-layer Wär ^¬ medämmschicht (13) is 500ym to 800ym

- for the lower ceramic layer {! '' ') partially stabilized zirconia and

for the upper ceramic layer (10 ')

partially stabilized zirconia is used

Zirconium oxide is used for the ceramic thermal barrier coating (7 ', 7' ', 13') or the ceramic layers {! '' ', 10'), and the monoclinic fraction of the powder to be sprayed under o,

especially below 1.5%,

more particularly at least 0.3%,

the tetragonal portion in zirconium oxide has the largest proportion,

in particular at least 60%,

especially at least 75%,

- oxide by a heat treatment of the monoclinic fraction of the zirconia, and in particular to be sprayed powder to Minim ^¬ least 50% is reduced,

especially below the detection limit,

the lower layer {1 '' ') is sprayed without polymer and the upper layer (10') is sprayed with polymer,

- The average pore diameter (Dio) of the upper ceramic layer (10 ') is generated larger as the average pore diameter (d ₇ ) of the lower ceramic layer {! '''),

especially at least 20μιη,

the same powder having the same composition and the same particle size distribution is used,

a different material is used for the lower ceramic layer {1 '''') than for the upper ceramic layer (10 ') _/ in particular zirconium oxide for the lower layer {1'''),

in particular a pyrochlore for the upper layer (10 ') _/ - a single-layer metallic layer is replaced by a two-layer metallic layer,

a two-layer metallic layer is replaced by a single-layer metallic layer,

- The chemical composition of the metallic protective layer is changed, but not the position of Metalli ^¬ rule protective layer

- Has the single-layer metallic protective layer

(in% by weight):

29% - 31% nickel (Ni),

27% - 29% chromium (Cr),

7% - 8% aluminum (AI),

0.5% -0.7% yttrium (Y),

0.3% - 0.7% silicon (Si),

no rhenium (Re),

Balance cobalt (Co),

- The single-layer metallic protective layer contains the following elements

(In% by weight):

24% - 26% cobalt (Co),

16% - 18% chromium (Cr)

9% - 12% aluminum (AI)

0.1% - 0.7% yttrium (Y) and / or

at least one equivalent metal from the group comprising scandium and the elements of the rare earths,

optional 1.0% to 2.0% rhenium (Re)

Nickel,

especially the rest of nickel,

- the single-layer metallic protective layer having the following composition (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 12% - 14%,

Aluminum (AI): 10, 0% - 12, 0%,

Yttrium (Y): 0.2% - 0.4%,

in particular 0.3%,

Nickel,

k3 mj. -LZZ ^ j.9. c3.TZ1 <n

- the chromium content in a two-layer metallic protective layer for the lower metallic protective layer between the

Chromium content of the substrate and the chromium content of the outer metallic protective layer,

in particular in which the metallic protective layers comprise an alloy MCrAlX,

in the case of a two-layer NiCoCrAlY protective layer, the outer protective layer comprises tantalum (Ta) or tantalum (Ta) and iron (Fe),

- the lower NiCoCrAlY layer has the following composition ^¬ (% in wt .-):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 12% - 14%,

Aluminum (AI): 10.0% - 12.0%,

Yttrium (Y): 0.2% - 0.4%, nsk) € 5 om -t ^ 5 clä.ZLZS. i) 65ST € szit

in which the upper NiCoCrAlY layer has the following composition (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 23% - 25%,

Aluminum (AI): 9.5% - 11, 5%,

Yttrium (Y): 0.2% - 0.4%,

ZLZ χζι ί Ίζζ n- _* Show it:

1 to 3 embodiment of the invention,

Figure 4 shows a pore distribution in a ceramic

Layer,

FIG. 5 shows 8 exemplary embodiments of the invention,

9 shows a turbine blade and

Figure 10 is a gas turbine. The description is only an exemplary embodiment of the invention ^¬.

An interval of maintenance of gas turbines 100 (Figure 6) is determined by detecting operating hours and starts, which are dependent on the mode of operation and certain factors. Maintenance must be carried out after reaching the hourly or start limit. If maintenance is required depending on the field of application of the gas turbine, or if the use requires an overhaul or another use beforehand, then the configuration of the gas turbine 100 is changed. Definition of terms:

First gas turbine has 1st turbine blade with 1st metallic protective layer.

Second gas turbine has turbine blades with metallic protective coating

a) in which the first turbine blades (= second turbine show ^¬ fel) and / or

b) new, unused turbine blades (= new second Turbi ^¬ nenschaufeln)

be used

and each having a second metallic protective layer significantly below ^¬ distinguishable from the first metallic protective layer. Likewise, in addition to the change of the metallic protective layer, the definition of the term also applies if, in addition, the thermal barrier coating is changed.

First gas turbine has 1st turbine blade with 1st thermal insulation ^¬ layer.

Second gas turbine has turbine blades with ceramic thermal barrier coatings

a) where the first turbine blades (= second turbine blade) and / or

b) new, unused turbine blades (= new second Turbi ^¬ nenschaufeln)

be used

and in each case a second thermal barrier layer clearly distinguishable from the first thermal barrier coating.

A single-layer metallic protective layer, especially with the composition NiCoCrAlX is suitable for a "Daily Starter".

The change in the layer always means a change in the chemical composition, especially because a lower and upper metallic protective layer differ significantly in their composition, ie. at least one alloying element has an at least 15% Various ^¬ NEN portion.

Figure 5 shows a substrate 4 having a single-layer metalli ^¬ rule protective layer 16 is removed, and is changed for the production of second turbine acting ^¬ feln or new second turbine blades in its layer thickness 16 'of a first turbine blade.

In addition, but not necessarily, the alloy of the original metallic protective layer 16 may be altered. In Figure 6 it is shown that a two-layer metallic protective layer 22 ', 22''from the first turbine blades is removed and a single-layer metal as a new second protective layer is applied ^¬ 22nd

The layer thickness of the single-layer metallic protective layer 22 may preferably correspond to that of the two metallic protective layers 22 ', 22 ". At least one alloy of one of the two metallic protective layers 22 ', 22 "may also correspond to the alloy of the single-layer layer 22 or may be entirely different from one another.

In Figure 7 it is shown that a single-layer metallic protective layer 16 is removed from a substrate 4 of first turbine blades and is also replaced by a single layer metal as a new second protective layer 16 ''', wherein at least the chemical composition of the alloy coins ^¬ tion as described above, has changed significantly.

In particular, the layer thickness can change.

FIG. 8 shows that a single-layer metallic protective layer 16 is removed from a substrate 4 of first turbine blades and a two-layer metallic new protective second layer 24 ', 24 "is applied.

The layer thickness of the two-layer metallic protective layer 24 ', 24 "may preferably correspond to that of the original single-layer metallic protective layer 16.

Preferably, the two alloys are the two-ply

However, this need not be the case, ie at least one alloy of the two-layer protective layer 24 ', 24 "may correspond to the alloy of the single-layer protective layer 16. The variation of the metallic protective layers according to FIGS. 5, 6, 7 and / or 8 can be varied with the variation of the ceramic protective layers according to FIGS. 1, 2 and 3.

A preferred metallic single-layer protective layer comprises:

(in% by weight)

24% - 26% cobalt,

16% - 18% chromium,

9% - 11% aluminum,

0.11% - 0.7% yttrium

and optionally 1.0% - 2.0% rhenium and

Rest on nickel

or

in which the single-layer metallic protective layer

having the following composition (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 12% - 14%,

Aluminum (AI): 10, 0% - 12.0%,

Yttrium (Y): 0.2% - 0.4%,

-L m <C _' <in.cj- -r ^* d. (3- c5iTJI <<^" t ^ In. ^" T- or

wherein the single layer metallic protective layer comprises: 29% - 31% nickel (Ni),

27% - 29% chromium (Cr),

7% - 8% aluminum (AI),

0.5% -0.7% yttrium (Y),

0.3% - 0.7% silicon (Si),

no rhenium (Re),

Balance cobalt (Co). A two-layer MCrAlX layer 24 ', 24''is suitable for long-term operation (base loader). A two-layer metallic protective layer 24 ', 24 "has a lower metallic protective layer, in particular of an alloy of the type NiCoCrAlX, whose chromium content is preferably between that of the substrate and the chromium content of the outer metallic protective layer

Differences in the content of chromium (Cr) at least absolutely be sailed ^¬ hen 2%.

For a two-layer metallic protective layer 24 ', 24 "based on the NiCoCrAlX alloys, it is preferable to use a tantalum or tantalum / iron-containing outer metallic protective layer.

An advantageous composition for the outer protective layer results from (in% by weight)

25% cobalt (Co),

24% chromium (Cr),

10.5% aluminum (AI),

0.3% yttrium (Y),

Remainder nickel (Ni)

such as

preferably for a lower layer

25% cobalt (Co),

13% chromium (Cr),

11% aluminum (AI),

0.3% yttrium (Y),

Balance nickel (Ni) for the outer NiCoCrAlX layer (X = Y).

Preferably, the following combination results:

in which the lower NiCoCrAlY layer has the following composition (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 12% - 14%,

Aluminum (AI): 10, 0% - 12, 0%,

Yttrium (Y): 0.2% - 0.4%,

1Ι1 S fc € 3 S O Ί ζ5 (j. Si -TT clU S l S t € 3 In t

in which the upper INIiCoCJ-ΓΑ.1Y ScInicInt fo1gende composition au fwe is (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 23% - 2 5%,

Aluminum (AI): 9, 5% - 11, 5%,

Yttrium (Y): 0.2% - 0.4%,

in particular 0.3%,

1SJ1 c * * ^ 1 ^

ln sk) son CL ^ ES JT ^ 5 d3..i 9.u. st * 5 t € 5 In. t · Depending on the operation of a single layer 16 is applied through a two-ply layer 24 ', 24''on the back up processing ^¬ ended blade or a two-tiered layer is replaced by a single-layer metallic protective layer. Was previously in this first gas turbine, a single-layer heat ^¬ insulation layer as described above in operation exists, is for reuse in the base load operation, a two ^¬ ply (Fig. 3), a thicker (Fig. 1) or more porous ceramic j ^¬ specific thermal barrier coating for the turbine blades 120, 130 used.

The turbine blades for the second gas turbine may be at the origin (same substrate) the first turbine blades of the first gas turbine or other gas turbines already in use, refurbished accordingly, and re-coating second turbine blades

new second turbine blades, where newly manufactured (newly cast), not yet used turbine show fine

be coated differently than the first turbine blades of the first gas turbine.

It is likewise possible, when the gas turbine 100 has a two-layer ceramic thermal barrier coating on the turbine blades 120, 130, to apply a single-layer TBC so that it can then be used in peak load mode (FIG. 2). For the peak load operation preferably only one ply ^¬ a ceramic layer is used with a uniform porosity. For the peak-load operation, the ceramic thermal barrier coating on the turbine blades 120, 130 preferential ^¬ as a high porosity of 18% ± 4%.

In base load operation, however, a two-layer thermal barrier coating 13 is used (FIG. 3).

As a starting powder for the ceramic layers 7 ', 7' ',

1 '", 10', 13 'is preferably agglomerated, sintered

Powder used. Each ceramic sprayed layer is applied in coating layers. Two-ply means, however, that a second layer differs from a first, lower layer due to porosity and / or microstructure and / or chemical composition.

The lower layer used is preferably a ceramic layer 7 with a porosity of 12% ± 4%, which preferably has a layer thickness of 75 μm to 150 μm.

In addition, a porosity of 18% ± 4% is sprayed or is present as outer ceramic layer 10.

However, the difference in porosity is at least 2%, especially at least 4%. Variations in the porosity in the production are known. Within a batch, i. of a blade set, there are no fluctuations.

As a lower layer, a ceramic layer is also preferably 7 having a porosity of 12% ± 4%, the preference ^¬ a layer thickness of 75ym having up 150ym.

However, the difference in porosity is at least 2%, especially at least 4%. Fluctuations in porosity in the production are known. Within a batch, ie a blade set, no fluctuations are ver ^¬ draw. As a lower layer, a ceramic layer is also preferably 7 having a porosity of 18% ± 4%, the preference ^¬ a layer thickness of up to 75ym having 150ym.

In addition, a porosity of 25% ± 4% is sprayed or present as outer ceramic layer 10.

However, the difference in porosity is at least

2%, in particular at least 4%. Variations in the porosity in the production are known. Within a batch, ie a blade set, no fluctuations are ver ^¬ draw.

In order to produce porosities in ceramic layers or ceramic layers (FIGS. 1-3), coarse grains may be used in the spraying and polymer use or smaller grains may be used, wherein roughly means at least 20% larger average particle diameter.

A two-layer ceramic layer 7, 10 can be manufactured with Various ^¬ NEN Spraying: the lower layer 7 is without polymer and the upper layer 10 is injected ^¬ ver with polymer.

This results in the upper layer 10 larger pores, ie, the average pore diameter dio increases over the average pore diameter d _{7 of} the lower layer 7 (FIG. 4). This is not necessarily true. A higher porosity is often achieved only by a higher number of pores of the same pore size.

Preferably, the same powder is used, so also a same particle size distribution.

Zirconium oxide (ZrÜ ₂₎ for the ceramic layers of the thermal barrier ^¬ layers preferably has a monoclinic fraction of < 3%, in particular -S 1.5%. Corresponding portions then has a ceramic layer or layer 7, 7 ', 10, 13 (FIGS. 1-3) on the turbine blade 120, 130. The minimum proportion of the monoclinic phase is at least 1%, in particular 0.5%, in order not to increase the cost of the powder too much.

By changing the configuration of the first thermal insulation layer 7 ', 7'',13' quasi another, second Gastur ^¬ bine is produced, which is optimized for their application.

FIG. 9 shows a perspective view of a rotor blade or guide vane 130 of a turbomachine that extends along a longitudinal axis 121.

The turbomachine may be a gas turbine of an aircraft or a power plant for electricity generation, a steam turbine or a compressor.

The blade 120, 130 has along the ^longitudinal axis 121 to each other, a securing region 400, an adjoining blade or vane platform 403 and a blade 406 and a blade tip 415.

As a guide vane 130, the vane 130 having at its blade ^tip 415 have a further platform (not Darge ^¬ asserted). In the mounting region 400, a blade root 183 is formed, which serves for attachment of the blades 120, 130 to a shaft or a disc (not shown).

The blade root 183 is, for example, as a hammerhead out staltet ^¬. Other designs as fir tree or Schwäbwschwanzfuß are possible.

The blade 120, 130 has for a medium which flows past the scene ^¬ felblatt 406 on a leading edge 409 and a ^trailing edge 412th In conventional blades 120, 130, in all regions 400, 403, 406 of the blade 120, 130, for example, ^massive metallic materials, in particular superalloys, are used.

Such superalloys are known, for example, from EP 1 204 776 B1, EP 1 306 454, EP 1 319 729 A1, WO 99/67435 or WO 00/44949.

The blade 120, 130 can be made by a casting process, also by directional solidification, by a forging process, by a milling process or combinations thereof.

Workpieces with a monocrystalline structure or structures are used as components for machines which are exposed to high mechanical, thermal and / or chemical stresses during operation.

The production of such monocrystalline workpieces takes place e.g. by directed solidification from the melt. These are casting processes in which the liquid metallic alloy is transformed into a monocrystalline structure, i. to the single-crystal workpiece, or directionally solidified.

Here, dendritic crystals are aligned along the heat flow and form either a columnar grain structure (columnar, ie grains that run the entire length of the workpiece and here, in common parlance, referred to as directionally solidified) or a monocrystalline structure, ie the whole workpiece be ^¬ is made of a single crystal. In these methods, you have to avoid solidification transition to globular (polycrystalline), since non-directional growth inevitably forms transverse and longitudinal grain boundaries ^¬ which make the good properties of the directionally solidified or single-crystal component naught.

If the term "directionally solidified microstructures" is used, it refers both to single crystals which have no grain boundaries or at most small-angle grain boundaries, and to stem crystal structures which are likely to be found in longitudinal grooves. grain boundaries, but have no transverse grain boundaries. These second-mentioned crystalline structures are also known as directionally solidified structures.

Such methods are known from US Pat. No. 6,024,792 and EP 0 892 090 A1.

Likewise, the blades 120, 130 may have coatings against corrosion or oxidation, e.g. B. (MCrAlX; M is at least one element of the group iron (Fe), cobalt (Co),

Nickel (Ni), X is an active element and stands for yttrium (Y) and / or silicon and / or at least one element of the rare earths, or hafnium (Hf)). Such alloys are known from EP 0 486 489 B1, EP 0 786 017 B1, EP 0 412 397 B1 or EP 1 306 454 A1.

The density is preferably 95% of the theoretical

Density.

A protective aluminum oxide layer (TGO = thermal grown oxide layer) is formed on the MCrAlX layer (as an intermediate layer or as the outermost layer).

Preferably, the layer composition comprises Co-30Ni-28Cr-8A1-0, 6Y-0, 7Si or Co-28Ni-24Cr-10Al-0, 6Y. Besides these cobalt-based protective coatings, nickel-based protective layers such as Ni-10Cr-12Al-0.6Y-3Re or Ni-12Co-21Cr-IIAl-O, 4Y-2Re or Ni-25Co-17Cr-10A1-0, 4Y-1 are also preferably used , 5Re.

On the MCrAlX may still be present a thermal barrier coating, which is preferably the outermost layer, and consists for example of Zr0 ₂ , Y2Ü3-Zr02, ie it is not, partially ^¬ or fully stabilized by yttria

and / or calcium oxide and / or magnesium oxide.

The thermal barrier coating covers the entire MCrAlX layer.

Suitable coating processes, such as electron beam evaporation (EB-PVD), produce stalk-shaped grains in the thermal barrier coating. Other coating methods are conceivable, for example atmospheric plasma spraying (APS), LPPS, VPS or CVD. The heat insulation layer may have ^¬ porous, micro- or macro-cracked ^compatible grains for better thermal shock resistance. The thermal barrier coating is therefore preferably more porous than the

MCrAlX layer.

Refurbishment means that components 120, 130 may have to be freed from protective layers after use (eg by sandblasting). This is followed by removal of the corrosion and / or oxidation layers or products. Optionally, even cracks in the component 120, 130 are repaired. Thereafter, a ^¬ As the coating of the component 120, 130, after entry set of the component 120, the 130th

The blade 120, 130 may be hollow or solid. If the blade 120, 130 is to be cooled, it is hollow and may still have film cooling holes 418 (indicated by dashed lines).

FIG. 10 shows by way of example a gas turbine 100 in a longitudinal partial section.

The gas turbine 100 has a rotatably mounted about a rotational axis 102 ^¬ rotor 103 having a shaft 101, which is also referred to as the turbine rotor.

Along the rotor 103 follow one another an intake housing 104, a compressor 105, for example, a toroidal combustion chamber 110, in particular annular combustion chamber, with a plurality of coaxially arranged burners 107, a turbine 108 and the exhaust housing 109th

The annular combustion chamber 110 communicates with an annular annular hot gas channel 111, for example. There, for example, four turbine stages 112 connected in series form the turbine 108.

Each turbine stage 112 is formed, for example, from two blade ^rings . In the flow direction of a working medium As can be seen in the hot gas duct 111 of a guide blade row 115, a row 125 formed of rotor blades 120 follows.

The guide vanes 130 are fastened to an inner housing 138 of a stator 143, whereas the moving blades 120 of a row 125 are attached to the rotor 103 by means of a turbine disk 133, for example.

Coupled to the rotor 103 is a generator or work machine (not shown).

During operation of the gas turbine 100 104 air 135 is sucked by the compressor 105 through the intake housing and ver ^¬ seals. The 105 ^¬ be compressed air provided at the turbine end of the compressor is supplied to the burners 107, where it is mixed with a fuel. The mixture is then burned to form the working fluid 113 in the combustion chamber 110. From there, the working medium 113 flows along the hot gas channel 111 past the guide vanes 130 and the rotor blades 120. The working medium 113 expands on the rotor blades 120 in a pulse-transmitting manner, so that the rotor blades 120 drive the rotor 103 and drive the machine connected to it ,

The components exposed to the hot working medium 113 are subject to thermal loads during operation of the gas turbine 100. The guide vanes 130 and rotor blades 120 of the first turbine stage 112, viewed in the flow direction of the working medium 113, are subjected to the highest thermal stress in addition to the heat shield elements lining the annular combustion chamber 110.

To withstand the prevailing temperatures, they can be cooled by means of a coolant.

Likewise, substrates of the components may have a directional structure, i. they are monocrystalline (SX structure) or have only longitudinal grains (DS structure).

As a material for the components, in particular for the turbine ^¬ blade 120, 130 and components of the combustion chamber 110 are For example, iron-, nickel- or cobalt-based superalloys used.

Also, the blades 120, 130 may be anti-corrosion coatings (MCrAlX; M is at least one element of the group iron (Fe), cobalt (Co), nickel (Ni), X is an active element and is yttrium (Y) and / or silicon , Scandium (Sc) and / or at least one element of the rare earth or hafnium). Such alloys are known from EP 0 486 489 B1, EP 0 786 017 B1, EP 0 412 397 B1 or EP 1 306 454 A1. On the MCrAlX may still be present a thermal barrier coating, and consists for example of Zr02, Y203-Zr02, ie it is not, partially or completely stabilized by Ytt ^¬ riumoxid and / or calcium oxide and / or magnesium oxide.

By suitable coating methods, e.g. Electron beam evaporation (EB-PVD) produces stalk-shaped grains in the thermal barrier coating.

The guide blade 130 has a guide blade root facing the inner housing 138 of the turbine 108 (not shown here) and a guide blade foot opposite

Guide vane head on. The vane head faces the rotor 103 and fixed to a mounting ring 140 of the stator 143.

Claims

Patent claims

1. Procedure

to produce a second gas turbine,

in which, starting from a ^first gas turbine, at least a first metallic protective layer (16, 22 ', 22 '') is removed from the first turbine blades of the first gas turbine and

a new second metallic protective layer (16', 16''', 22, 24', 24'') is applied to the stripped first turbine blades for producing second turbine blades (7),

and or

on new second turbine blades,

that were newly manufactured for the first time,

the new second metallic protective layer (16', 16''', 22, 24', 24'') is applied,

which (16', 16''', 22, 24', 24'') ^differs significantly from the first metallic protective layer (16, 22, 22''),

where distinction means at least:

the layer thickness (16') is different,

where the difference is in the reduced and enlarged

Layer thickness is at least 50μη,

and or

the alloy of the second metallic protective layer

(16''') is different,

wherein the relative difference in at least one alloy ^element is at least 15%

and or

the layering of the metallic protective layer is ^different ,

in particular the one or two layers of the metallic protective layer (22, 24', 24''),

and wherein the new second and/or the second turbine blades are installed in the first gas turbine to produce the second gas turbine.

2. Method according to claim 1,

in which, starting from a first gas turbine, at least a first ceramic thermal insulation layer (7, 13) is removed from the first turbine blades of the first gas turbine and a new second ceramic thermal insulation layer (7 ', 7'', 13') is used to produce second turbine blades ( 7) is applied to the stripped first turbine blades and/or to new second turbine blades,

that were newly manufactured,

the new second ceramic thermal insulation layer (7 ', 7'', 13') is applied,

which (7', 7'', 13') differs significantly from the first ceramic thermal insulation layer (7, 13),

where distinction means at least:

the layer thickness is different,

where the difference in the reduced and increased layer thickness is at least 50μη,

and or

the porosity is different,

where the absolute difference in reduced or increased porosity is at least 2%

and or

the positioning is different,

in particular the one or two layers of the ceramic thermal insulation layer (7', 7'', 13') _/

3. Method according to claim 1,

in which only the metallic adhesion promoter layer is changed for the second gas turbine.

4. The method according to one or both of claims 1 or 2, in which the metallic adhesive ^layer and the ceramic layer thereon are changed for the second gas turbine.

5. Method according to claim 4,

in which a two-layer ceramic thermal insulation layer (13) is removed from the first turbine blades and / or a single-layer thermal insulation layer {1 '') is applied as a second ceramic thermal insulation layer to the second or new second ^turbine blades.

6. Method according to claim 5,

in which the single-layer ceramic thermal insulation layer {1 '' ) with a porosity of 18% ± 4% is produced.

7. Method according to claim 4,

in which a single-layer thermal insulation layer (7) is removed from the first turbine blades and/or

a two-layer thermal insulation layer (13') is applied as a second ^ceramic thermal insulation layer to the second or new second turbine blades,

in particular a two-layer thermal insulation layer (13 ').

8. Method according to one or more of claims 4, 5, 6 or 7,

in which the porosity of the second ceramic thermal insulation layer (7 ', 7'', 13') of the second or new second turbine blades is increased compared to the porosity of the thermal insulation layer of the first turbine blades.

Method according to one or more of claims 4, 5, or 7,

in which the porosity of the second ceramic thermal insulation layer (7 ', 7'', 13) of the second or new second turbine blades is reduced compared to the porosity of the thermal insulation layer of the first turbine blades.

10. Method according to one or more of claims 4 to 8,

in which a thinner ceramic thermal insulation layer (7) as the first ceramic thermal insulation layer is replaced by a thicker ceramic thermal insulation layer (7 ', 13') as the second ceramic thermal insulation layer of the second or the new second turbine blades,

whereby the difference in thickness ^is at least +50μη.

11. Method according to one or more of claims 4 to 9,

in which a thicker ceramic thermal insulation layer as the first ceramic thermal insulation layer is replaced by a thinner ceramic thermal insulation layer as the second ceramic thermal insulation layer of the second or the new second turbine blades,

where the difference in thickness is at least 50μη.

12. Method according to one or more of claims 7 to 11,

in which the two-layer thermal insulation layer (13 ') with a bottom ceramic layer {!''') with a porosity of 12% ± 4% and

is produced with an outer ceramic layer (10 ') with a porosity of 18% ± 4%,

where the absolute difference in the porosity of the ^ceramic layers {!''', 10') is at least 2%,

in particular 4%,

in particular a maximum of 4%.

13. Method according to one or more of claims 7 to 11,

in which the two-layer thermal insulation layer (13) with a bottom ceramic layer {!''') with a porosity of 18% ± 4% and

with an outer ceramic layer (10 ') with an equal porosity of 18% ± 4%.

14. Method according to one or more of claims 7 to 11,

in which a two-layer thermal insulation layer (13 ') with a bottom ceramic layer {!''') with a porosity of 18% ± 4% and

is produced with an outer ceramic layer (10 ') with a porosity of 25% ± 4%,

in particular 4%,

in particular a maximum of 4%.

15. Method according to one or more of claims 7 to 14,

in which the lower layer {!''') of the two-layer thermal insulation ^layer (13) is thinner, in particular at least 20% thinner, than the upper layer (10'),

in particular in which the lower layer {!''') of the two-layer thermal insulation layer (13) has a ^thickness of 75ym to 150ym,

in particular, the total layer thickness of the two-layer thermal insulation layer (13) is 500ym to 800ym.

16. Method according to one or more of claims 7 to 15,

in which for the lower ceramic layer {!''') ^partially stabilized zirconium oxide and

for the upper ceramic layer (10')

partially stabilized zirconium oxide is used.

17. Method according to one or more of the previous claims 4 to 16,

in which zirconium oxide is used for the ceramic thermal insulation layer (7', 7'', 13') or the ceramic layers {!''', 10'),

and the monoclinic proportion of the powder to be sprayed is less than 3%,

in particular below 1.5%,

in particular at least 0.3%.

18. Method according to one or both of claims 16 or 17,

in which the tetragonal portion in zirconium oxide has the largest proportion,

in particular at least 60%,

especially at least 75%.

19. Method according to claim 17 or 18,

in which the monoclinic proportion of the zirconium oxide, in particular the powder to be sprayed, is reduced by at least 50% through heat treatment,

especially below the detection limit.

20. Method according to one or more of claims 7

19,

in which the lower layer (Ί ' ') is sprayed without polymer and the upper layer (10') is sprayed with polymer.

21. Method according to one or more of claims 7 to 20,

in which the average pore diameter (di o) of the upper ceramic layer (10') is made larger

as the average pore diameter (d ₇ ) of the lower ceramic layer {!'''),

especially by at least 20μιη.

22. Method according to one or more of claims 2 to 21,

in which the same powder with the same composition and grain size distribution is used.

23. Method according to claims 7 to 21,

in which a different material is used for the lower ceramic layer {!''') than for the upper ceramic layer (10'),

in particular zirconium oxide for the lower layer {!'''), especially a pyrochlore for the upper layer (10').

24. Method according to one or more of claims 1 to 23,

in which a single-layer metallic layer (16) as the first metallic protective layer is replaced by a two-layer metallic layer (24', 24'') as a new second metallic protective ^layer .

25. Method according to one or more of claims 1 to 23,

in which a two-layer metallic layer (22', 22'') as the first metallic protective layer is replaced by a single-layer ^metallic layer (22) as a new second metallic protective ^layer .

26. Method according to one or more of claims 1 to 25,

in which the chemical composition of the new second metallic protective layer (16''') is changed,

but in particular not the layering of the metallic protective layer.

27. Method according to one or more of claims 1 to 26,

in which the single-layer metallic protective layer (22, 16 ',

16''') as a new second metallic protective layer

(in% by weight):

29% - 31% Nickel (Ni),

27% - 29% Chromium (Cr),

7% - 8% aluminum (AI),

0.5% - 0.7% yttrium (Y),

0.3% - 0.7% silicon (Si),

no rhenium (Re),

Rest cobalt (Co).

28. Method according to one or more of claims 1 to 26,

in which the single-layer metallic protective layer (22, 16', 16''') contains the following elements as a new second metallic protective layer

(Data in wt.%):

24% - 26% cobalt (Co),

16% - 18% Chromium (Cr)

9% - 12% aluminum (AI)

0.1% - 0.7% yttrium (Y) and/or

at least one equivalent metal from the group comprising scandium and the rare earth elements,

optional 1.0% to 2.0% rhenium (Re)

Nickel,

especially the rest nickel.

29. Method according to one or more of claims 1 to 26,

in which the single-layer metallic protective layer (22, 16 ',

16''') as a new second metallic protective layer

has the following composition (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 12% - 14%,

Aluminum (AI): 10.0% - 12.0%,

Yttrium (Y): 0.2% - 0.4%,

in particular 0.3%,

30. Method according to one or more of claims 1 to 26,

in which the chromium content in a two-layer metallic protective layer (24', 24'') as a new second metallic protective layer

for the lower metallic protective layer (24') lies between the chromium content of the substrate and the chromium content of the outer metallic protective layer (24''),

in particular in which the metallic protective layers have an alloy MCrAlX.

31. Method according to one or more of claims 1 to 26,

in which, in the case of a two-layer NiCoCrAlY protective layer (24' 24''), the outer protective layer (24'') has tantalum (Ta) or tantalum (Ta) and iron (Fe).

32. Method according to one or more of claims 1 to 26,

in which, as the second metallic protective layer, the lower NiCoCrAlY layer (24 ') has the following composition (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 12% - 14%,

Aluminum (AI): 10.0% - 12.0%,

Yttrium (Y): 0.2% - 0.4%,

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in which the upper NiCoCrAlY layer (24'') has the following ^composition (in% by weight):

Cobalt (Co): 24% - 26%,

Chromium (Cr): 23% - 25%,

Aluminum (AI): 9.5% - 11.5%,

Yttrium (Y): 0.2% - 0.4%,

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33. Method for operating a gas turbine system, in which the type of metallic and optionally ceramic layers of turbine blades of the gas turbine (100) is changed,

in particular according to claims 1 to 32.

34. Method according to claim 33,

in which the gas turbine starts daily,

in particular in which the gas turbine was manufactured according to claim 25, 27, 28 or 29.

35. Method according to claim 33,

in which the gas turbine ^operates continuously for several days,

in particular in which the gas turbine was manufactured according to 24, 30, 31 or 32.