CH709649A2 - Turbine blade assembly and gas turbine system with a turbine blade assembly. - Google Patents

Abstract

The invention relates to a turbine blade assembly and a gas turbine system with a turbine blade assembly. The turbine blade assembly (200) includes a connection (108) having a single projection (108) and a one-piece platform (112), the connection (108) having a first axial length; an undivided profile (110) extending radially outwardly from the one-piece platform (112) and having a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel (105) having a receptacle with a geometry corresponding to the connection (108) with a single projection and connected to the connection (108) with a single projection. The connection (108) and the undivided profile (110) comprise a turbine blade material, and the turbine wheel (105) comprises a turbine wheel material, the turbine wheel material having lower heat resistance and higher thermal expansion than the turbine blade material.

Description

FIELD OF THE INVENTION

The present invention relates to turbine components and turbine systems. More particularly, the present invention relates to turbine blade assemblies and turbine systems having one or more turbine blade assemblies.

GENERAL PRIOR ART

At least some known gas turbines have a combustion chamber, a compressor and / or turbines having an impeller disc having a plurality of impeller blades, or blades, which extend radially outwardly therefrom. The plurality of rotating turbine blades or blades direct high temperature fluids, such as combustion gases or steam, through either a gas turbine or a steam turbine. The feet of at least some known blades are connected to the disk via dovetails which are inserted into corresponding dovetail slots formed in the impeller disk to form a bladed disk or "blisk". Since such turbines operate at relatively high temperatures and may be relatively large, the operating performance of such a turbine may be at least partially limited by the materials used in the manufacture of the blades and / or the length of the profile sections of the blades. To allow improved performance, at least some turbine manufacturers have increased the size of the turbines, thereby causing an increase in the length of the profile section of the blades. Such an extension may require increasing the size of the dovetails and dovetail slots to hold the longer blades in place.

Turbine blade assemblies, whether with or without repairable and / or replaceable profile tip sections, are subject to various forces. These forces require that different portions of the turbine blade assemblies have different properties. It is known that a change in density may be useful depending on the location of the material. However, further characterization of properties that provide beneficial results, especially with respect to particular materials, would provide additional benefits.

[0004] A turbine blade assembly and a turbine system with a turbine blade assembly with improvements would be desirable in the art.

BRIEF DESCRIPTION OF THE INVENTION

In one embodiment, a turbine blade assembly has a connection with a single projection and a one-piece platform, the connection having a first axial length; an undivided profile that extends radially outwardly from the one-piece platform and has a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the connection with a single projection and connected to the connection with a single projection. The undivided profile comprises a turbine blade material and the turbine wheel comprises a turbine wheel material, the turbine wheel material having a lower heat resistance and a higher thermal expansion than the turbine blade material.

In any embodiment of the turbine blade assembly, it may be advantageous for the turbine blade material to be a titanium aluminide.

In any embodiment of the turbine blade assembly, it may be advantageous for the turbine wheel material to be a superalloy.

In any embodiment of the turbine blade assembly, it may be advantageous for the turbine blade material to be less dense than the turbine wheel material.

In any embodiment, it may be advantageous that the turbine blade assembly further includes a tip shroud that is integrally placed on the tip end of the undivided profile.

In any embodiment of the turbine blade assembly, it may be advantageous for the tip shroud to include a sealing strip placed on an outer surface of the tip shroud distal to the connection with a single projection.

In any embodiment of the turbine blade assembly, it may be advantageous that the connection with a single projection via an axial connection, a peripheral connection, a dovetail connection, a groove connection, a tine connection, a tongue and groove connection or a combination thereof with detachable connected to the turbine wheel.

In any embodiment of the turbine blade assembly, it may be advantageous for the geometry of the turbine wheel corresponding to the connection to a single projection to define an edge of the turbine wheel.

In any embodiment, it may be advantageous for the turbine blade assembly to further include an impact protection strip placed at a leading edge of the undivided profile.

In any embodiment, it may be advantageous for the turbine blade assembly to further include an impact protection strip placed at a trailing edge of the undivided profile.

[0015] In any embodiment, it may be advantageous for the turbine blade assembly to further include an impact protection strip made of impact strip material capable of adhering to the turbine blade material.

In another embodiment, a turbine blade assembly has a connection with a single projection and a one-piece platform, the connection having a first axial length; an undivided profile that extends radially outwardly from the one-piece platform and has a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the connection with a single projection and connected to the connection with a single projection. The undivided profile comprises a turbine blade material and the turbine wheel comprises a turbine wheel material, wherein the turbine blade material is a titanium aluminide and the turbine wheel material is a superalloy.

In another embodiment, a turbine system includes a compressor section, a combustor section configured to receive air from the compressor section, and a turbine section in fluid communication with the combustor section, the turbine section including a stator and turbine blade assembly. The turbine blade assembly has a connection with a single projection and a one-piece platform, the connection having a first axial length; an undivided profile that extends radially outwardly from the one-piece platform and has a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the connection with a single projection and connected to the connection with a single projection. The undivided profile comprises a turbine blade material and the turbine wheel comprises a turbine wheel material, the turbine wheel material having a lower heat resistance and a higher thermal expansion than the turbine blade material.

In any embodiment, it may be advantageous for the turbine system to further include a plurality of axially spaced stages of turbine blade assemblies including a final stage of turbine blade assemblies.

In any embodiment of the turbine system, it may be advantageous that the profile has a leading edge and a trailing edge and further comprises at least one impact protection strip which is attached to the leading edge and / or the trailing edge.

[0020] In any embodiment of the turbine system, it may be advantageous for impact protection strips to be attached to the leading edge of the tip regions of the plurality of turbine blade assemblies in one or more of the plurality of turbine stages.

In any embodiment of the turbine system, it may be advantageous for impact protection strips to be attached to the trailing edges of the plurality of turbine blade assemblies in one or more of the plurality of turbine stages except the last stage.

Other features and advantages of the present invention will become apparent from the following more particular description of the preferred embodiment, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] <Tb> FIG. 1 <SEP> is a simplified illustration of a turbine system with a turbine blade assembly according to an embodiment of the disclosure. <Tb> FIG. 2 <SEP> is a perspective view of a turbine blade assembly having an undivided profile in a turbine blade according to an embodiment of the disclosure. <Tb> FIG. FIG. 3 is a plan view of the right side turbine blade of a rear stage (for example, a blade for use in a third or fourth stage of a four-stage turbine) according to an embodiment of the disclosure. FIG.

In all the drawings, if possible, the same reference numerals are used to represent the same parts.

DETAILED DESCRIPTION OF THE INVENTION

There is provided a turbine blade assembly and a turbine system. In addition, the disclosure discloses methods for mounting and / or manufacturing such turbine blade assemblies and turbine systems. Embodiments of the present disclosure, for example, as compared to similar concepts that do not include one or more of the features disclosed herein, reduce overall operating and overall maintenance costs, shorten the period of downtime for repairs, and allow for more convenient benefits or smaller turbines and / or turbine blades are used, portions of a turbine blade assembly may be exposed to higher temperatures, allowing properties in a particular portion of a turbine blade assembly to withstand additional forces, additional materials used for portions of turbine blade assemblies, or a combination thereof.

Fig. 1 is a simplified illustration of a turbine system 10, such as a gas turbine system, a power generation system, any other suitable system using blades / blades, or a combination thereof. The term "bucket" is used interchangeably with the term "bucket" here. A suitable turbine blade is illustrated in FIG. 3, which illustrates a blade for use in a turbine rear stage (eg, a third or fourth stage of a four-stage turbine). In one embodiment, the system 10 includes an inlet section 12, a compressor section 14 downstream of the inlet section 12, a combustor section 16 coupled downstream of the inlet section 12, a turbine section 18 coupled downstream of the combustor section 16, and an outlet section 20. The turbine section 18 is drivingly coupled to the compressor section 14 via a rotor shaft 22. The combustor section 16 has a plurality of combustors 24 and is coupled to the compressor section 14 such that each of the combustors 24 communicates with the compressor section 14 via fluid. With each of the combustion chambers 24, a fuel nozzle assembly 26 is connected. The turbine section 18 is rotatably coupled to the compressor section 14 and to a load 28, such as, but not limited to, an electric generator and / or a mechanical drive application. The compressor section 14 and / or the turbine section 18 include at least one blade or turbine blade 30 coupled to the rotor shaft 22.

During operation, the inlet section 12 directs air toward the compressor section 14. The compressor section 14 compresses the supply air to a higher pressure and a higher temperature and discharges the compressed air in the direction of the combustion chamber section 16. The compressed air is mixed with fuel and ignited to produce combustion gases that flow to the turbine section 18, which drives the compressor section 14 and / or the load 28. In particular, at least a portion of the compressed air is supplied to the fuel nozzle assembly 26. Fuel is directed to the fuel nozzle assembly 26. The fuel is mixed with the air and ignited downstream of the fuel nozzle assembly 26 in the combustor section 16. Combustion gases are generated and directed to the turbine section 18. Heat energy of the gas stream is converted into mechanical rotational energy in the turbine section 18. Exhaust gases flow out of the turbine section 18 and flow through the outlet section 20 into the ambient air.

FIG. 2 is a perspective view of a turbine blade assembly 200 with the turbine blade 30 that may be used with the system 10. The turbine blade 30 has a profile 110. The profile 110 is not subdivided (eg, does not have a separate tip portion and foot portion and / or represents a single continuous material, as shown in FIG. 2). The turbine blade 30 has a pressure side 102 and a suction side 103, which are connected to one another at a front edge 104 and a trailing edge 106. The pressure side 102 has a generally concave geometry and the suction side 103 has a generally convex geometry. The turbine blade 30 has a connection 108 and / or any other suitable features such as a platform 112 extending between the connection 108 and the profile 110.

The connection 108 connecting the blade 30 to the wheel 105 is a dovetail, has a plurality of projections, has a single projection, is a portion of a blisk, is integral with the profile 110 (for example, such that in FIG the turbine blade 30 where the platform 112 merges into the profile 110, there are no seams or inconsistencies) is another suitable mechanism or other suitable device for securing the turbine blade 30 or a combination thereof. The thermal expansion coefficients of the materials in the components (for example, a wheel 105 and the profile 110) dictate the type of connection between the respective components. For example, if the materials have an almost identical or identical coefficient of thermal expansion over a wide temperature range, the bond 108 between the components may be either a single boss or multiple boss joint. A multi-protrusion connection may be preferred in some circumstances. In contrast, if the materials have different thermal expansion coefficients, joining with a single protrusion between the components may be preferred.

In one embodiment, the turbine blade 30 is connected to the wheel 105 via the connection 108 and extends radially outward from the wheel 105. The link 108 has a single lug geometry corresponding to a respective receptacle in the wheel 105 and may be detachably or permanently connected to the wheel 105 by any suitable method. One suitable method includes detachably connecting the connection 108 to the wheel 105 via an axial connection or peripheral connection. Another suitable method includes detachably connecting the connection 108 to the wheel 105 via a dovetail joint, a grooved joint, a tine joint, a tongue and groove joint, or a combination thereof.

In one embodiment, the wheel 105 is a turbine wheel having a plurality of receptacles with a geometry corresponding to the links 108 having a single projection of a corresponding plurality of turbine blades 30, and the geometry of the wheel 105 defines an edge of the turbine wheel. In an alternative embodiment (FIG. 1), the turbine blades 30 are connected directly to the rotor shaft 22 via the connections 108 and extend radially outward from the rotor shaft 22.

In one embodiment, the connection 108 has an axial connection length 114 that facilitates securement. In one embodiment, platform 112 extends radially outwardly from link 108 and has a platform length 117 that corresponds or approximately corresponds to axial link length 114 (as shown in FIGS. 2 and 3).

In one embodiment, the profile 110 extends radially outward from the connection 108, extends radially outward from a platform outer surface of the platform 112, has an initial profile length 119 approximately equal to the axial connection length 114, and / or increases the length to a tip end length 118 at a tip end 116 of the turbine blade 30 so that the tip end length 118 is shorter in a profile view from the right than the axial connection length 114, as shown in Fig. 3. Tip tip length 118 and tip width may be varied depending on the application of turbine blade 30 and / or system 10. The profile 110 has a first or radial length 120 measured from the platform 112 to the tip end 116, for example, to allow improved performance of the turbine blade 30. The profile length 120 can be varied depending on the application of the turbine blade 30 or system 10. In one embodiment, the tread 110 has a tread width sized to facilitate securing to the wheel 105.

The profile 110 is an undivided portion of the turbine blade 30. In one embodiment, as shown in FIG. 2, the profile 110 includes a first portion or tip portion 122 that is integral with a second portion or foot portion 124 is trained. The foot region 124 is proximal to the wheel 105 or the rotor shaft 22 (see FIG. 1). The tip region 122 is located distally of the wheel 105 or the rotor shaft 22 (see FIG. 1), for example proximal to a tip shroud 109 or a sealing strip 111.

The tip region 122 has a tip section length 126 that is comparable to the turbine blade length 120 over, for example, a relative portion of the turbine blade length 120, for example, about 25 percent, about 40 percent, more than 40 percent, less than about 50 percent, about 50 percent, more than about 50 percent, about 60 percent, between about 40 percent and about 60 percent, about 75 percent, between about 25 percent and about 75 percent, between about 40 percent and about 75 percent, or any suitable combination, subcombination , any suitable area or subarea in it. The tip section length 126 extends to a central portion of the profile 110 having an axial length 129 which, in a profile view from the right, is longer than the tip end length 118 and shorter than the initial profile length 119, as shown in FIG.

The connection 108, the tread 110 and / or the wheel 105 comprise any suitable combination of materials that can withstand the operating requirements of the system 10 and / or work in conjunction with the features of the turbine bucket 30. The materials are similar materials, materials or materials that are selected to balance weight and cost considerations with performance at higher temperatures and / or speeds.

Suitable materials for bond 108 and profile 110 include, but are not limited to, ceramic matrix composites, titanium aluminide, materials with similar or lower thermal expansion than materials in wheel 105, materials having similar or higher heat resistance as materials in the wheel 105 (eg, to take into account that the tip region 122 is exposed to higher operating temperatures), materials having a similar or lower density than materials in the wheel 105 (resulting, for example, in a lower rotating mass in the turbine blade 30) or Combination of it. In one embodiment described herein, the profile 110 includes a titanium aluminide material.

The term "ceramic matrix composite" includes, but is not limited to, carbon fiber reinforced carbon (C / C), carbon fiber reinforced silicon carbide (C / SiC), and silicon carbide fiber reinforced silicon carbide (SiC / SiC). In one embodiment, the ceramic matrix composite has better elongation, fracture toughness, thermal cycling properties, dynamic resilience properties and anisotropic properties as compared to a monolithic ceramic structure.

As used herein, the term "titanium aluminide" includes, but is not limited to, conventional weight based compositions having about 45% Ti and about 50% Al (TiAl) and / or a mole ratio of about 1 mole Ti to about 1 mole Al, TiAl2 (for example, having a molar ratio of about 1 mole of Ti to about 2 moles of Al), TiAl3 (eg, having a molar ratio of about 1 mole of Ti to about 3 moles of Al), Ti3Al (e.g., having a molar ratio of about 3 moles of Ti to about 1 mole Al) or other suitable mixtures thereof.

Suitable materials for the wheel 105 include, but are not limited to, cobalt-base superalloys, nickel-base superalloys, steel-based superalloys, materials with similar or higher thermal expansion than materials in the profile 110, materials having a similar or lower Heat resistance as materials in the profile 110, materials of similar or higher density than materials in the profile 110, or a combination thereof.

The term "superalloy" here includes, but is not limited to, nickel-based alloys, cobalt-based alloys, or steel-based alloys. A typical nickel base superalloy material sold under the trade name INCONEL® 718 by Special Metal Corporation of New Hartford, NY has a weight average composition of about 50.0 to 55.0% Ni, about 17.0 to 21 , 0% Cr, about 4.75 to 5% Nb, about 2.8 to 3.3% Mo, about 1.0% Co, about 0.65 to 1.15% Al, about 0.35% Mn, about 0.35% Si, about 0.2 to 0.8% Cu, about 0.3% Ti, about 0.08% C, about 0.015% S, about 0.015% P, and about 0.006% B, and as a difference 100% Fe on. An exemplary CrMoV superalloy composition (based on steel) has a composition in weight% of about 0.90 to 1.50% Mo, about 0.90 to 1.25% Cr, about 0.55 to 0.90% Mn, about 0.35 to 0.55% Ni, about 0.25 to 0.33% C, 0.20 to 0.30% V, not more than about 0.35% Si, not more than about 0, 35% Cu, not more than 0.012% P, not more than about 0.012% S, and as a difference to 100% Fe and trace impurities.

Referring to Figure 2, in one embodiment, the turbine blade 30 has impact protection tabs 107 on the profile 110 that increase the impact resistance of the area to which they are attached. The bumper strips 107 may be made of a similar material as the profile 110 or other material and / or may have similar properties as the profile 110 or other properties. The bumpers 107 are placed (as shown) at the leading edge 104 of the turbine blade 30, the trailing edge 106 of the turbine blade 30, at the tip region 122, the root region 124, or a combination thereof. In one embodiment, the bumpers 107 are located at the leading edge 104 of the tip regions 122 at any and all turbine stages, whereas the bumpers 107 are at the trailing edge 106 of the tip regions 122 at any and all turbine stages except the last stage ,

The impact protection strips 107 are provided with one or more chemical and / or mechanical methods based, for example, on physically based methods (such as geometry) and material science methods (such as alloying). In one embodiment, the impact protection strips 107 are chemically attached, for example, by in-situ material processing such as casting, in situ extrusion, in situ forging, other suitable methods, or a combination thereof. Additionally or alternatively, in one embodiment, the bumpers 107 are chemically attached via a process such as diffusion bonding, brazing, welding, other suitable methods, or a combination thereof, via a raw material processing. In a further embodiment, the impact protection strips 107 are mechanically attached via adhesive, rivets, shaft pins, buttons or retaining connections (for example a groove connection, a tine connection and / or a tongue and groove connection), further suitable methods or a combination thereof.

While the invention has been described in terms of one or more embodiments, it will be understood by those skilled in the art that various changes may be made without departing from the scope of the invention and equivalents may be substituted for elements thereof. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its essential scope. The invention, therefore, should not be limited to the particular embodiment described as the best mode contemplated for this invention, but is intended to include all embodiments falling within the scope of the appended claims. In addition, all numerical values given in the detailed description shall be construed as expressly indicating both the exact and approximate values.

A turbine blade assembly and a turbine system are disclosed. The assembly has a connection with a single projection and a one-piece platform, the connection having a first axial length; an undivided profile that extends radially outwardly from the one-piece platform and has a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the connection with a single projection and connected to the connection with a single projection. The connection and the undivided profile comprise a turbine blade material and the turbine wheel comprises a turbine wheel material, the turbine wheel material having a lower heat resistance and a higher thermal expansion than the turbine blade material.

Claims (10)

A turbine blade assembly comprising: a connection with a single projection and a one-piece platform, the connection having a first axial length; an undivided profile that extends radially outwardly from the one-piece platform and has a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the connection with a single projection and connected to the connection with a single projection; wherein the undivided profile comprises a turbine blade material and the turbine wheel comprises a turbine wheel material, the turbine wheel material having a lower heat resistance and a higher thermal expansion than the turbine blade material. 2. The assembly of claim 1, wherein the turbine blade material is a titanium aluminide and / or wherein the turbine wheel material is a superalloy and / or wherein the turbine blade material is less dense than the turbine wheel material. The assembly of claim 1 or 2, further comprising a tip shroud integrally placed on the tip end of the undivided profile and wherein the tip shroud comprises a sealing strip placed on an outer surface of the tip shroud distal to the connection with a single protrusion , 4. Arrangement according to one of the preceding claims, wherein the connection with a single projection via an axial connection, a peripheral connection, a dovetail connection, a groove connection, a tine connection, a tongue and groove connection or a combination thereof is detachably connected to the turbine wheel. 5. Arrangement according to one of the preceding claims, wherein the geometry of the turbine wheel, which corresponds to the connection with a single projection defines an edge of the turbine wheel. 6. An assembly according to any one of the preceding claims, further comprising an impact protection strip placed at a leading edge of the undivided profile. An assembly according to any one of the preceding claims, further comprising an impact protection strip placed at a trailing edge of the undivided profile. 8. An assembly according to any one of the preceding claims, further comprising an impact protection strip made of impact strip material capable of adhering to the turbine blade material. 9. A turbine blade assembly comprising: a connection with a single projection and a one-piece platform, the connection having a first axial length; an undivided profile that extends radially outwardly from the one-piece platform and has a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the connection with a single projection and connected to the connection with a single projection; wherein the single lobe connection and the undivided profile comprise a turbine blade material and the turbine wheel comprises a turbine wheel material, wherein the turbine blade material is a titanium aluminide and the turbine wheel material is a superalloy. 10. A gas turbine system comprising: a compressor section; a combustor section configured to receive air from the compressor section; and a turbine section in fluid communication with the combustor section, the turbine section including a stator and turbine blade assembly, the turbine blade assembly comprising: a connection with a single projection and a one-piece platform, the connection having a first axial length; an undivided profile that extends radially outwardly from the one-piece platform and has a tip end having a second axial length that is shorter than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the connection with a single projection and connected to the connection with a single projection; wherein the undivided profile comprises a turbine blade material and the turbine wheel comprises a turbine wheel material, the turbine wheel material having a lower heat resistance and a higher thermal expansion than the turbine blade material.