DE102020201448A1 - Additively manufactured turbine blade with anti-twist device and adjustment process - Google Patents

Abstract

A turbine blade (10) is specified, comprising a blade (17) and a base plate (13) with a receptacle (14) for mounting the blade (10) during operation, for example in a turbo-engine (100), and a stop surface (15) , 15 '), wherein the receptacle (14) and the stop surface (15, 15') are arranged and designed to prevent rotation of the turbine blade (10) during operation, the receptacle (14) on the inflow side approximately in the center of the Base plate (13) is arranged. Furthermore, a turbine, a method for the additive manufacture of the turbine blade and a method for aligning the adjustment of the turbine blade are specified.

Description

The present invention relates to a turbine blade, preferably a turbine guide vane of a gas turbine for generating energy, as well as a turbine in which said turbine blade can be used. Furthermore, a method for the additive manufacture of the turbine blade and a method for aligning the turbine blade in a turbine ring are specified.

In gas turbines, thermal energy and / or flow energy of a hot gas generated by the combustion of a fuel, e.g. a gas, is converted into kinetic energy (rotational energy) of a rotor. For this purpose, a flow channel is formed in the gas turbine, in the axial direction of which the rotor or a shaft is mounted. If a hot gas flows through the flow channel, a force is applied to the rotor blades, which is converted into a torque acting on the shaft, which drives the turbine rotor, whereby the rotational energy can be used, for example, to operate a generator.

Modern gas turbines are subject to constant improvement in order to increase their efficiency. However, this leads, among other things, to ever higher temperatures in the hot gas path. The metallic materials for rotor blades, especially in the first stages, are constantly being improved with regard to their strength at high temperatures (creep load, thermomechanical fatigue).

Due to its potential to disrupt industry, generative or additive manufacturing is also becoming increasingly interesting for the series production of the above-mentioned turbine components, such as turbine blades or burner components.

Additive manufacturing processes include, for example, powder bed processes such as selective laser melting (SLM) or laser sintering (SLS), or electron beam melting (EBM). Further additive processes are, for example, "Directed Energy Deposition (DED)" processes, in particular laser deposition welding, electron beam or plasma powder welding, wire welding, metallic powder injection molding, so-called "sheet lamination" processes, or thermal spray processes (VPS LPPS, GDCS).

A method for selective laser melting is known from, for example EP 2 601 006 B1 .

Additive manufacturing processes have also proven to be particularly advantageous for complex or filigree components, for example labyrinth-like structures such as sealing elements, cooling structures and / or generally lightweight structures. In particular, additive manufacturing is advantageous due to a particularly short chain of process steps, since a manufacturing or manufacturing step of a component can largely take place on the basis of a corresponding CAD file and the selection of corresponding manufacturing parameters.

Many gas turbines use a pin or similar means for fixing the corresponding component for fixing, in particular the turbine guide vane of the first stage (s). This pin is usually inserted into a type of bore or through hole in the component. Since this alone does not ensure anti-rotation protection, further features are required to prevent undesired movement of the component in the turbine. For example, additional stop surfaces can be provided for fixing.

During assembly, the component or the component must usually continue to be held or fixed, for example via an integrated sealing spring and / or a sealing slot, together with a neighboring component, such as a further turbine (guide) vane, or with a further part, such as a turbine (lead) ring. During operation of the turbine blade, and consequently under load, the component is inadvertently set into motion or rotation due to the relationships between pressure and temperature on an airfoil of the turbine blade. A rotation can result, in particular, about an axial or fluid flow direction if the turbine blade is not adequately secured against rotation. In particular, each individual turbine blade can continue to rotate in the direction of the suction side. In order to absorb this movement or force, an elevation with a stop surface can be provided, by means of which a rotation of the turbine blade against the corresponding turbine guide ring is to be prevented.

The problem described appears all the more serious the greater the tolerance and the weaker the dimensional accuracy in the manufacture of the turbine blade, and thus, for example, a deviation of the abovementioned stop surface from an optimal position or effect. If, for example, the stop surface is not positioned exactly or rests against a counterpart of a guide ring, the entire load is inevitably absorbed by the sealing elements, such as sealing spring and / or sealing slot, when the blade is in operation. This can lead to sealing gap losses in the working medium of the turbine and / or the destruction of the sealing elements on the blades.

Care must therefore be taken to ensure that the components are dimensionally accurate, which in turn places very high costs and demands on production. The high costs of conventional manufacturing processes with regard to the casting techniques involved and the provision of the casting tools and the associated high throughput time are known.

Furthermore, the effort involved in aligning or adjusting the turbine guide vane in the turbine in conventional manufacturing processes is considerable.

It is therefore an object of the present invention to provide an improved mounting method for turbine blade components, both during their installation and during the operation of a turbine, and to provide corresponding means.

This object is achieved by the subject matter of the independent claims. Advantageous configurations are the subject of the dependent claims.

One aspect of the present invention relates to a turbine blade, comprising a blade and a base plate with a receptacle or suspension for mounting or fixing the blade during operation, for example in a turbo machine such as a gas turbine for generating energy.

The base plate furthermore has a stop surface, the receptacle and the stop surface being arranged and designed to provide anti-twist protection for the turbine blade during operation of the turbine blade, the receptacle being arranged approximately centrally on or in the base plate on the inflow side.

The term “central” preferably denotes a central arrangement of the receptacle along a tangential direction or circumferential direction of the blade ring or the step to which the turbine blade is assigned in its operation.

The blade of the turbine blade expediently has a leading edge and a trailing edge, and preferably a so-called suction side and a pressure side.

In the present case, the footplate preferably denotes a shroud, a collar or a blade root. The turbine blade is expediently attached or coupled to a rotor or stator ring, such as a turbine guide ring, in its intended operation.

Like the described receptacle, the stop surface is also preferably arranged on the inflow side, i.e. on an inflow side of the turbine blade or on a side towards which the inflow edge of the turbine blade faces.

Advantageously, the presented turbine blade makes it possible to dispense with changing or adapting a component that carries the turbine blade, such as a turbine running ring or turbine guide ring, for example. In other words, the new blades presented can be integrated into existing “hardware” without any geometrical adjustment.

Furthermore, the mounting variant according to the invention offers the advantage that other sealing concepts, for example without changing the geometry of a turbine guide ring, can be used for the components / blades described.

In one embodiment, the turbine blade is a turbine guide vane, in particular for a thermal and / or stationary turbo machine for generating energy.

In one embodiment, the receptacle is designed for, in particular mechanical, coupling to a counterpart of a turbine ring, for example a guide ring.

In one embodiment, the exception or the suspension is an, in particular round, through hole.

In one embodiment, the receptacle is a blind hole or a bore.

In one embodiment, the stop surface comprises two partial surfaces that are separate from one another. This configuration can advantageously optimize the weight of the turbine blade with sufficient mechanical stability and accuracy of fit. For a new type of manufacturing route for the turbine blade described, for example by means of additive manufacturing, this means weight optimization and a saving in raw material.

In other words, the provision of several small separate surfaces instead of one large stop surface advantageously saves material and valuable process time at the same time.

In one embodiment, the partial areas are arranged opposite to the center of the base plate and spaced apart. With this configuration, in which, for example, viewed in the circumferential direction of a guide vane ring, a stop surface is provided on each side of the receptacle, a particularly efficient mounting and / or anti-rotation lock of the Turbine blade can be guaranteed. In particular, this configuration advantageously enables the effect of a two-point anti-rotation lock, in which fewer mounting points are required than with comparable, conventionally manufactured turbine blades.

In one embodiment, the anti-rotation lock is a two-point anti-rotation lock. A twisting or unwanted rotation of the turbine blade during operation is thereby brought about, firstly, efficiently by the suspension and, secondly, by the stop surface.

In one embodiment, both partial surfaces of the stop surface - taken together - extend over more than half of the inflow-side expansion of the footplate. This configuration advantageously makes it possible to achieve a particularly large stop surface and thus efficient anti-twist protection with small movement tolerances during operation.

In one embodiment, one or each of the partial areas in turn comprises two separate and preferably spaced apart lower partial areas. With this configuration, a (further) weight optimization of the turbine blade can advantageously also be achieved with sufficient mechanical stability and accuracy of fit.

In one embodiment, the lower sub-surfaces are spaced apart from one another in a direction extending from an inflow side to an outflow side of the turbine blade. This configuration also advantageously enables a (further) weight optimization of sufficient mechanical stability and accuracy of fit of the blade.

In one embodiment, the footplate has a lattice structure. With this configuration, the weight of the component can be further reduced with tolerable mechanical stability. At the same time - similar to the configurations described above - manufacturing costs can be reduced by providing novel, additive methods.

In one embodiment, the lattice structure is arranged and designed to facilitate or support an adjustment of the blade when the blade is installed, for example in a turbo-engine, in particular on a turbine guide ring. The aforementioned alignment or adjustment is preferably still carried out with eccentric pins. The aforementioned simplification of the adjustment is achieved in that the lattice structure can absorb mechanical forces during the adjustment, in particular to optimize the sealing gap.

In one embodiment, the lattice structure has lattice elements that are made thin enough to be deformed when the blade is installed in a turbine, in particular to optimize the sealing gap.

In one embodiment, the turbine blade is free of sealing slots and / or sealing springs. In other words, the turbine blade advantageously does not have any sealing elements connected to it in one piece. This can in particular facilitate the manufacture of the turbine blade.

Another aspect of the present invention relates to a turbine comprising a turbine blade as described above or an arrangement of such turbine blades, the turbine further comprising a turbine ring to which the turbine blades are attached.

Another aspect of the present invention relates to a method for the additive manufacture of the turbine blade, in particular by means of a laser-assisted, powder-bed-based approach. This manufacturing method advantageously makes it possible to significantly shorten the product throughput time of corresponding components, in particular by several months, as well as to design the components with improved geometries and properties, which up to now could not be achieved conventionally or only at great cost.

In one embodiment, the lattice structure is or is not or is hardly reworked mechanically, in particular after its additive construction. The above-described configuration of the turbine blade with the lattice structure predestines the blade precisely for the additive manufacturing processes mentioned. Using conventional manufacturing methods in particular, the formation of a lattice structure - as described above - is technically or economically impossible.

Another aspect of the present invention relates to a method for aligning or adjusting a turbine blade in a turbine ring, such as a turbine guide ring, the lattice structure being deformed, in particular to optimize the sealing gap.

Refinements, features and / or advantages that in the present case relate to the turbine blade or the turbine can furthermore relate to the additive manufacturing method described or the adjustment method, or vice versa.

The term "and / or" as used herein, when used in a series of two or more elements, means that any of the The items listed can be used alone, or any combination of two or more of the items listed can be used.

• 1 zeigt vereinfachte perspektivische Ansicht eines Teils einer bekannten Turbinenleitschaufel.
• 2 zeigt einen Teil einer perspektivischen oder Seitenansicht eines Schaufelfußes einer Turbinenschaufel gemäß der vorliegenden Erfindung.
• 3 zeigt eine vereinfachte perspektivische Ansicht eines Schaufelfußes der Turbinenschaufel gemäß einer alternativen Ausgestaltung.
• 4 zeigt eine schematische perspektivische Ansicht einer Turbine oder eines Teils davon, umfassend eine Anordnung von Turbinenschaufeln wie oben beschrieben.

Further details of the invention are described below with reference to the figures.

• 1 Figure 12 shows a simplified perspective view of part of a known turbine guide vane.
• 2 Figure 12 shows part of a perspective or side view of a blade root of a turbine blade according to the present invention.
• 3 shows a simplified perspective view of a blade root of the turbine blade according to an alternative embodiment.
• 4th shows a schematic perspective view of a turbine or a part thereof, comprising an arrangement of turbine blades as described above.

In the exemplary embodiments and figures, elements that are the same or have the same effect can each be provided with the same reference symbols. The elements shown and their proportions to one another are fundamentally not to be regarded as true to scale; rather, individual elements can be shown exaggeratedly thick or with large dimensions for better illustration and / or for better understanding.

1 shows a known turbine blade 10 ' in a partial view. In particular, the turbine blade 10 ' represent a turbine vane. The turbine guide vane is preferably provided for use in a thermal and / or stationary fluid flow machine, such as a gas turbine for generating energy.

Mainly is in 1 a footplate or a blade root 3 the turbine blade 10 ' shown. A shovel blade 7th the turbine blade 10 ' is indicated in the lower area of the illustration.

The turbine blade 10 ' furthermore has an upstream side 1 on. On the opposite side of the blade root 3 is a trailing edge 2 the turbine blade 10 ' with the reference number 2 marked.

The direction y extends from the upstream side 1 to the downstream side 2 the shovel 10 ' . The direction or axis y can further denote an axial direction or fluid flow direction when reference is made to an operation of the turbine blade in a turbo machine (cf. also FIG 4th ).

The direction or axis x preferably denotes a direction perpendicular to the direction y, which also corresponds to a circumferential or tangential direction of a corresponding arrangement of turbine blades in a blade ring or a turbine stage.

It is also inside the blade root 3 indicated a contour of the blade. However, a leading edge and a trailing edge are not explicitly identified with reference symbols.

The blade root 3 furthermore has a mount or suspension 4th on, which is on an upstream side 1 the footplate 3 is arranged. About this recording 4th the blade is preferably used for operation in a turbine (see reference number 100 below) coupled to or attached to a turbine ring. The one with R. indicated arrow is intended to rotate or move the turbine blade 10 ' imply. Such a rotation can occur, in particular, about the axial direction y if there is no adequate bearing or anti-rotation device for the turbine blade. The rotation R. is drawn in such a way that the airfoil 7th the turbine blade 10 ' on the suspension 4th rotates or moves in the direction of a suction side of the turbine blade.

In order to prevent such a movement, the turbine blade shown also has a stop surface 5 which prevents excessive movement of the individual turbine blades when a turbine is in operation, in that the stop surface strikes a counterpart, for example a turbine ring.

Furthermore, the turbine blade shown 10 ' a sealing slot 6th or a sealing spring (not explicitly marked). This sealing slot 6th During operation of this known design, the blade can also function as part of the bearing, fixing or anti-twist device, although an (additional) mechanical load would then be absorbed by the sealing slot. Under certain circumstances, this can also lead to leakage losses at the sealing point.

2 shows in contrast to 1 part of a turbine blade 10 according to the present invention. Again, it is mainly a blade root or a footplate 13th shown. This turbine blade 10 expediently also has a turbine blade 17th on, which is only hinted at in the lower part. An upstream side is denoted by the reference symbol 11 indicated.

The footplate 13th assigns a recording 14th , similar to the recording described 4th on. Furthermore, the footplate 13th a stop surface 15th on. In contrast to the known design, this design is characterized by the fact that the recording 14th and the stop surface 15th (also compare the reference numbers 15 ' and 15 '' ) are arranged and designed to effect an anti-rotation lock, in particular only a two-point anti-rotation lock, of the turbine blade when the turbine blade is in operation, the receptacle 14th Is arranged on the inflow side approximately centrally on or in the base plate.

The recording 14th is preferably - similar to a bore - designed as a round or circular through hole for the coupling of a counterpart to a turbine guide ring.

In contrast, in 1 It can be clearly seen that the suspension is also arranged on the inflow side, but closer to a pressure-side end (left in the illustration) of the footplate than to a suction-side end (right).

This “central” or central arrangement or configuration of the receptacle 14th , has the advantage that the corresponding blade component can be fixed, installed and / or stored in an improved manner both during assembly and during operation, without changes to the load-bearing component, in particular the turbine guide ring, being required. Furthermore, if at all necessary, sealing elements, such as sealing springs or sealing slots, can be significantly relieved of mechanical stress and, or in general, completely different sealing concepts can be used. This in 2 Shown design of the turbine blade 10 is preferably free of sealing elements. The stop surface also contributes to these effects 15th is raised compared to other areas of the footplate.

The stop surface 15th is, as shown by way of example, in a plurality, in particular two, partial areas 15 ' divided, said sub-areas 15 ' are spaced from each other by the distance a. Each of these sub-areas 15 ' is according to 2 opposite on each other side (right and left) along an extension A. of the blade root 13th arranged. Between the partial areas 15 ' a recess (not explicitly marked) is arranged, at the height of which the suspension is located in the circumferential direction x 14th is located. Both partial areas preferably extend 15 ' taken together over more than half of the upstream expansion A. .

Technical advantages continue to arise, for example, from a further subdivision of the stop surface 15th in subareas 15 '' . In the present case, this subdivision does not take place along the x direction, but along the axial direction y (see also 3 ). In particular, a saving in weight can be optimized and the production of the component can be simplified as a whole. The lower part surfaces 15 " are therefore preferably spaced apart from one another by a distance b along the direction x.

3 shows a simplified perspective view of the footplate 13th from below, without indicating the blade of the turbine blade. It is also shown there that the turbine blade 10 filigree structures, such as a lattice structure 18th having. The lattice structure 18th is at the top right of the illustration 3 , so in the vicinity of the inflow side of the turbine blade, arranged.

Overall is the lattice structure 18th preferably arranged and designed, when installing the blade, for example in a turbomachine, an adjustment of the blade 10 to assist, or to facilitate. The lattice structure shows more precisely 18th Lattice elements (not explicitly identified) which are made thin enough to be deformed if necessary when installing the blade or aligning it to optimize the sealing gap.

In a corresponding adjustment method or method for aligning the turbine blade, the lattice structure can be deformed advantageously and in a controlled manner. In this case, preferably no lattice elements are broken off, but rather the deformation preferably takes place smoothly and brings about a stable positionability or adjustability of the turbine blade 10 relative to a turbine ring (compare reference numbers 30th in 4th ) and possibly adjacently arranged further turbine blades of the corresponding stage. The lattice structure may be effective 18th in this adjustment with another stop or counterpart of a turbine ring.

Such lattice structures cannot be produced, or cannot be produced economically, using conventional production methods.

Therefore, the turbine blade according to the present invention is preferably manufactured by an additive manufacturing technology, in particular powder-bed-based methods, such as selective laser sintering, selective laser melting or electron beam melting. The processes mentioned are part of the so-called “powder bed fusion” process. A design of the component provided, for example, by way of a CAD file (“Computer-Aided Manufacturing”) is read into a processor of the system and preferably divided into individual layers of less than 50 µm thick, which is then applied in the form of powder on a building platform and then selectively with an energy beam, preferably a laser beam or Electron beam, melted and solidified according to the desired geometry.

As a result, there is a great deal of design freedom in the manufacture of the components, which, for example, also enables or predestines the manufacture of the grid elements, as described above. With regard to the structural quality of the components, additive manufacturing methods are usually somewhat inferior to conventional manufacturing routes. This is due, among other things, to the large temperature gradients of sometimes more than 10 ⁶ K / s, which are caused by the very local energy input of the energy beam and make the structures obtained susceptible to hot or solidification cracks.

When producing the lattice structure for the present turbine blade, it is preferably not mechanically reworked afterwards, i.e. after the actual additive structure. Post-processing is particularly obsolete since the lattice structures, as described above, are deformed in any case when the blade is installed. As a result, the entire production of the component, for example compared to conventional production approaches, can advantageously continue to be significantly shortened.

4th shows a schematic partial view of a turbine 100 . Although only parts of the turbine are indicated in the illustration, relates to the turbine 100 preferably a complete gas turbine for generating energy or for the industrial use of turbines or drives in general.

The turbine 100 preferably comprises several turbine stages, but in any case one rotor or rotor blade ring 20th . A rotational or axial direction is again indicated with the reference symbol x. It also includes the turbine 100 a turbine ring 30th , which in operation of the turbine 100 expediently with a plurality of turbine guide vanes 10 (as described above) is equipped. About appropriate recordings 14th the blades are preferably on the turbine ring 30th attached. An arrangement of the turbine blades is denoted by the reference symbol 50 indicated. Furthermore, the arrow F indicates a fluid flow or flow direction.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 2601006 B1 [0006]

Claims (14)

Turbine blade (10), comprising a blade (17) and a base plate (13) with a receptacle (14) for mounting the blade (10) during operation, for example in a turbo machine (100), and a stop surface (15, 15 ') , wherein the receptacle (14) and the stop surface (15, 15 ') are arranged and designed to effect anti-twist protection of the turbine blade (10) during operation, the receptacle (14) on the inflow side approximately in the center of the base plate (13) is arranged. Turbine blade (10) according to Claim 1 , which is a turbine guide vane, in particular for a thermal flow machine for power generation. Turbine blade (10) according to Claim 1 or 2 , wherein the receptacle (14) is designed for coupling to a counterpart of a turbine ring (30). Turbine blade (10) according to one of the preceding claims, wherein the receptacle (14) is an, in particular round, through hole. Turbine blade (10) according to one of the preceding claims, wherein the stop surface (15) comprises two separate partial surfaces (15 '), and the partial surfaces (15') are arranged opposite the center of the base plate (13) at a distance (a). Turbine blade (10) according to Claim 5 , wherein the two partial surfaces (15 ') together extend over more than half of the inflow-side extension (A) of the base plate (13). Turbine blade (10) according to Claim 5 or 6th wherein one of the partial surfaces (15 ') in turn comprises two separate lower partial surfaces (15 "), the lower partial surfaces (15") extending in a direction from an inflow side (11) to an outflow side (12) of the blade (10) (y) are spaced apart (b). Turbine blade (10) according to one of the preceding claims, wherein the anti-rotation lock is a two-point anti-rotation lock. Turbine blade (10) according to one of the preceding claims, wherein the base plate (13) has a lattice structure (18) which is arranged and designed to support an adjustment of the blade (10) when installing the blade, for example in a turbo machine. Turbine blade (10) according to Claim 9 , the lattice elements of the lattice structure (18) being made thin enough to be deformed when installing the blade (10) to optimize the sealing gap. Turbine blade (10) according to one of the preceding claims, wherein which is formed free of sealing slots (6). Turbine (100) comprising an arrangement (50) of turbine blades according to one of the preceding claims, further comprising a turbine ring (30) to which the turbine blades (10) are attached. A method for the additive manufacture of a turbine blade (10) according to one of the Claims 9 until 12th , which is a particularly laser-assisted powder bed process (LPBF), and wherein the lattice structure (18) is in particular not mechanically reworked. Method for aligning a turbine blade (10) according to one of the Claims 1 until 11 in a turbine ring (30), the lattice structure (18) being deformed, in particular to optimize the sealing gap.

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