EP2491339A1

EP2491339A1 - Surface analysis for detecting closed holes, and device

Info

Publication number: EP2491339A1
Application number: EP10765789A
Authority: EP
Inventors: Georg Bostanjoglo; Torsten Melzer-Jokisch; Andreas Oppert; Dimitrios Thomaidis
Original assignee: Siemens AG; Chromalloy Gas Turbine Corp
Current assignee: Siemens AG
Priority date: 2009-10-20
Filing date: 2010-10-13
Publication date: 2012-08-29
Also published as: US8437010B2; JP2013508697A; KR20120083481A; JP5596163B2; CN102667399B; EP2314987A1; RU2532616C2; WO2011047995A1; US20120268747A1; CN102667399A; RU2012120338A

Abstract

By carrying out laser triangulation measurements on an uncoated component and a coated component with holes, the exact position of the holes to be reopened can be detected following the coating.

Description

Surface analysis for the detection of closed holes and

contraption

The invention relates to a method for surface analysis for the detection of sealed holes.

When repairing turbine blades, remove the used ceramic protective layer and reapply after repair. During the coating process, the existing cooling air holes are partially or completely closed. The position and orientation of the borehole axes of the cooling air holes are not or only partially determined. So far, the holes have been partially identified by finding slight depressions of the ceramic layer and / or smaller openings and opened by means of a hand ^¬ process. A safe, controllable system is not available. It is therefore an object of the invention to solve the above-mentioned problem.

The object is achieved by a method according to claim 1, 6 and device according to claim 7.

In the dependent claims further advantageous measures are listed, which Kings are combined with each other arbitrarily NEN to achieve more advantages.

Show it:

FIGS. 1, 2, 3 schematically show the sequence of the method;

FIG. 4 shows a gas turbine,

FIG. 5 shows a turbine blade,

FIG. 6 shows a combustion chamber,

Figure 7 is a list of superalloys. The description and the figures represent only embodiments of the invention.

In Figure 1, a coating 4 of model determined Geo ^¬ metriedaten of two holes with coating (not shown), respectively.

Also shown is a mask model 19 with theoretical assumptions about the position 7 ', 7 "of at least one hole and the orientation 13', 13" of the hole.

The mask pattern 19 may be determined 130 by measurement of the non-coated ^¬ member 120.

Preferably, by means of triangulation measuring methods, the surface of curved surfaces can be determined in an acceptable resolution and in a very short time in several dimensions.

The blade 120, 130, here as an exemplary component, is scanned in the uncoated state at the relevant points in order to determine the position of the holes and / or the position of the holes

Defining axes of the holes. This data is later in the computing unit 16 as the mask pattern 19 (Fig. 1, 2) utilization ^¬ det.

Likewise, known geometry data of the component 120, 130 can be used as the mask model 19, which in advance is e.g. are known from the production.

In any case, hole axis, hole angle (position of the hole) must be present in a data set (19 in Fig. 2).

Figure 2 shows that the computing unit 16 obtains data of a mask pattern 19 or ^¬ known geometry data 5 which are gemes ^¬ sen. Thereafter, a coating of the component 120, 130 takes place. Then, the coated component 120, 130 is measured again, in particular by means of laser triangulation, resulting in a coating model 4. In combination with a previously determined orientation 7 ', 7''of the hole or holes, an exact position and direction indication of cooling air holes in the coated / closed state is possible.

Here an iterative comparison 17 of the two models 4, 19 takes place until the position or center of the hole and the drilling axis are determined.

Thereby to determine the center of the hole and axis location of the unsealed hole is the position of the well of a trough 10 ', 10''of a completely sealed hole or the position 10', 10 '' of the opening in a partially closed hole herangezo ^¬ gene. Likewise, the border of the trough 10 ', 10''with the umran ^¬ tion of the hole can be compared (Fig. 3) to determine the position of the hole. Here, the outline of the trough 10 must ', whether small or large, depending on the coating from a certain ^¬ direction in the border 7' comprise, here, for example, concentrically (Fig. 3). If there are several holes, the best fit is determined iteratively over all holes. Only then can the reopening be carried out.

Computer-aided, the center point of a hole can now be calculated (17 in FIG. 2) and a reopening program can be generated, which allows the removal of the coat down from the hole.

In addition to the computer-aided determination of position and angle data for cooling air holes below a coating, the exact position of the cooling air bore for each individual blade and in each production state is the decisive advantage here. The distortion of a blade 120, 130 during coating can currently only be predicted with empirically determined procedures. This one

The methodology used can check this prediction and determine an exact position (step 17 in FIG. 2). FIG. 4 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 with a shaft, 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 . As seen in the direction of flow of a working medium 113, in the hot gas channel 111 of a row of guide vanes 115, a series 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 ge ^¬ leads to the burners 107, where it is mixed with a fuel. The mixture is then burned to form the working medium 113 in the combustion chamber 110. From there, the working medium flows

113 along the hot gas channel 111 past the guide vanes 130 and the blades 120. On the blades 120, the working medium 113 relaxes in a pulse-transmitting manner, so that the blades 120 drive the rotor 103 and drive the machine coupled 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, for example, iron-, nickel- or cobalt-based 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 guide vane 130 has an inner housing 138 of the turbine 108 facing guide vane root (not Darge here provides ^¬) and a side opposite the guide-blade root vane root. The vane head faces the rotor 103 and fixed to a mounting ring 140 of the stator 143.

5 shows a perspective view of a rotor blade 120 or guide vane show ^¬ 130 of a turbomachine, which extends along a longitudinal axis of the 121st

The turbomachine may be a gas turbine of an aircraft or a power plant for power 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.

The blade 120, 130 can hereby be manufactured 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, for example, by directed solidification from the melt. These are casting processes in which the liquid metallic alloy to monocrystalline structure, ie 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 generally refers to directionally solidified structures, it means both single crystals that have no grain boundaries or at most small-angle grain boundaries, and stem crystal structures that have grain boundaries running in the longitudinal direction but no transverse grain boundaries. In these second-mentioned crystalline

Structures are also called 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.

By suitable coating methods, e.g. Electron beam evaporation (EB-PVD) produces 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 insulating layer can comprise 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. The blade 120, 130 may be hollow or solid. If the blade 120, 130 is to be cooled, it is hollow and also has, if necessary, film cooling holes 418 ^(indicated by dashed lines) on.

6 shows a combustion chamber 110 of the gas turbine 100. The combustion chamber 110 is configured, for example, as so-called ^an annular ^combustion chamber, in which a plurality of in the circumferential direction about an axis of rotation 102 arranged burners 107 open into a common combustion chamber space 154, the flames 156 generate. For this purpose, the combustion chamber 110 is configured in its entirety as an annular structure, which is positioned around the axis of rotation 102 around. To achieve a comparatively high efficiency, the combustion chamber 110 is designed for a comparatively high temperature of the working medium M of about 1000 ° C to 1600 ° C. To even with these operating parameters unfavorable for the materials, a comparatively long operating time to be made ^¬ union, the combustion chamber wall 153 is provided on its side facing the ^working medium M facing side with a formed from heat shield elements 155. liner.

Due to the high temperatures inside the combustion chamber 110 may also be provided for the heat shield elements 155 and for their holding elements, a cooling system. The heat shield elements 155 are then, for example, hollow and possibly still have cooling holes (not shown) which open into the combustion chamber space 154.

Each heat shield element 155 made of an alloy is equipped on the working fluid side with a particularly heat-resistant protective layer (MCrAlX layer and / or ceramic coating) or is made of high-temperature-resistant material (solid ceramic blocks).

These protective layers may be similar to the turbine blades, so for example MCrAlX means: 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.

On the MCrAlX, for example, a ceramic Wär ^¬ medämmschicht be present and consists for example of ZrÜ2, Y203 ^~ Zr02, ie it is not, partially or completely stabilized by yttrium and / or calcium oxide and / or magnesium oxide. 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.

Reprocessing (Refurbishment) means that turbines ^¬ blades 120, 130, heat shield elements have to be removed from 155, after ^¬ A set of protective layers (for example by sandblasting). This is followed by removal of the corrosion and / or oxidation layers or products.

Optionally, cracks in the turbine blade 120, 130 or the heat shield element 155 are also repaired. This is followed by a re-coating of the turbine blades 120, 130, heat shield elements 155 and a renewed use of the turbine blades 120, 130 or the heat shield elements 155.

Claims

claims

1. A method for surface analysis of openable, at least partially closed holes of a component

(120, 130) after a coating,

in which a component (120, 130) with the non-sealed

Holes in the uncoated state is measured and a

Mask model (19) is generated

in particular by means of laser triangulation measurement, (19) at least the position of the holes as well as the

Orientation of their longitudinal axes,

or that the mask model (19) is known in advance from a data record,

and that a measurement,

in particular by means of laser triangulation,

with the coated component (120, 130) and thereby at least partially closed holes is performed,

wherein the data set thus generated is the coating model

(4) represents and

that the mask model (19) is compared with the coating model (4),

to allow the detection of the closed holes.

2. The method according to claim 1,

wherein the mask model (19) from the design of the component (120, 130) is known in advance.

3. The method according to claim 1 or 2,

in which by iteration the best possible match of mask model (19) and coating model (4) is determined.

Method according to claim 1, 2 or 3,

in which completely closed holes are detected in particular only sealed holes are detected.

5. The method according to claim 1, 2, 3 or 4,

wherein only partially occluded holes detects the ^¬,

In particular, only partially closed holes are detected.

6. A method for re-opening coated holes of a component (120, 130),

in which the position and orientation of the holes through a

A method according to claim 1, 2, 3, 4 or 5 is detected, and reopening the holes with a machining program obtained by the comparison of mask model (19) and

Coating model (4) was generated.

7. Device,

in particular for carrying out the method according to claim 1, 2, 3, 4 or 5,

which has:

a holder for the component (120, 130)

the component (120, 130)

a measuring sensor,

in particular a sensor for laser triangulation,

an arithmetic unit with memory unit for mask models

(19) and coating models (4) and

for the iterative determination of the position and orientation of the holes,

and in particular for generating a

Editing program.