EP3708774A1 - Guide blade and stationary cascade for a turbomachinery - Google Patents
Guide blade and stationary cascade for a turbomachinery Download PDFInfo
- Publication number
- EP3708774A1 EP3708774A1 EP19162485.7A EP19162485A EP3708774A1 EP 3708774 A1 EP3708774 A1 EP 3708774A1 EP 19162485 A EP19162485 A EP 19162485A EP 3708774 A1 EP3708774 A1 EP 3708774A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- guide blade
- hub
- trailing edge
- guide
- turbomachinery
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000003466 welding Methods 0.000 claims abstract description 35
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000013021 overheating Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000008719 thickening Effects 0.000 description 3
- 230000006378 damage Effects 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/147—Construction, i.e. structural features, e.g. of weight-saving hollow blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/141—Shape, i.e. outer, aerodynamic form
- F01D5/145—Means for influencing boundary layers or secondary circulations
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/18—Hollow blades, i.e. blades with cooling or heating channels or cavities; Heating, heat-insulating or cooling means on blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/22—Blade-to-blade connections, e.g. for damping vibrations
- F01D5/225—Blade-to-blade connections, e.g. for damping vibrations by shrouding
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D9/00—Stators
- F01D9/02—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
- F01D9/04—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
- F01D9/041—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector using blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2230/00—Manufacture
- F05D2230/20—Manufacture essentially without removing material
- F05D2230/23—Manufacture essentially without removing material by permanently joining parts together
- F05D2230/232—Manufacture essentially without removing material by permanently joining parts together by welding
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2240/00—Components
- F05D2240/10—Stators
- F05D2240/12—Fluid guiding means, e.g. vanes
- F05D2240/122—Fluid guiding means, e.g. vanes related to the trailing edge of a stator vane
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2240/00—Components
- F05D2240/10—Stators
- F05D2240/12—Fluid guiding means, e.g. vanes
- F05D2240/125—Fluid guiding means, e.g. vanes related to the tip of a stator vane
Definitions
- the present invention related to a guide blade for a turbomachinery, whereby the guide blade comprising a leading edge and a trailing edge which extend from a hub part to a tip part of the guide blade.
- the present invention related also to a stationary cascade for a turbomachinery, comprising a hub and a tip ring and a number of guide blades which are welded between the hub and the tip ring, whereby the hub parts of the guide blades are welded at the hub and the tip parts of the guide blades are welded at the tip ring.
- Stationary cascades comprising a hub and a tip ring and a number of guide blades.
- the guide blades are fixed at the hub and the tip ring.
- the tip ring has a hole which shape is similar to the guide blade profile, so that the guide blade could plug into the hole and fixed by a pin.
- This solution is probably shown in DE 195 47 653 C2 .
- a disadvantage of such a solution is that for each guide blade an own profiled hole is necessary which make this solution complicate and expensive.
- a cheaper solution is, to fix the guide blade by a welding process between the hub and the tip ring. Due to the very thin thickness of the trailing edge of the guide blade compared to thickness of the hub and the tip ring there is a technical problem during the welding process. The high temperature of the welding process and the thin thickness of the trailing edge lead to a so called "burn out" of the material of the trailing edge which lead in the worst case to a destruction of the guide blade.
- Aforesaid object is solved by a guide blade to independent claim 1 and a stationary cascade to independent claim 3.
- the inventive guide blade for a turbomachinery whereby the guide blade comprising a leading edge and a trailing edge which extend from a hub part to a tip part of the guide blade is characterized in that, an additional welding boss is designed on the trailing edge.
- the welding boss leads to a thickening of the trailing edge, so that the trailing edge is protected for a burn out while welding.
- An embodiment of the guide blade is characterized in that the additional welding boss is arranged only at the hub part and/or tip part of the guide blade.
- the guide blade will be welded only with the hub part to a hub and the tip part to a tip ring, so that only the welding zone should be thickening. Arranging the welding boss only in these zones the weight of the guide blade could be reduced and the flow over the guide blades will not be disturbed.
- the inventive stationary cascade for a turbomachinery comprising a hub and a tip ring and a number of guide blades which are welded between the hub and the tip ring, whereby the hub parts of the guide blades are welded at the hub and the tip parts of the guide blades are welded at the tip ring, is characterized in that the guide blades are guide blades according claim 1 or 2.
- the welding boss allows by thickening at least the welding zone at the hub part and/or tip part of the guide blade the welding without a risk of burn out and destruction of the trailing edge.
- An embodiment of the stationary cascade is characterized in that the welding boss is almost or completely melted by a welding procedure and protects the shape of the trailing edge from being destroyed by overheating through the welding procedure.
- the welding boss is dimensioned in that way, that the boss is generally melt by the welding procedure and is just big enough to protect the trailing edge and do not create any additional material which had to be reworked to keep the required designed channel for a media flow. This simplified the manufacturing and reduced the manufacturing time which leads to a cheaper stationary cascade.
- Figure 1 shows an inventive guide blade 1.
- the guide blade 1 comprising a leading edge 2 and a trailing edge 3.
- the leading edge 2 and the trailing edge 3 extend from a hub part 4 to a tip part 5 of the guide blade 1.
- the guide blade 1 is usually used to build a stationary cascade 7 for a turbomachinery which will show and described in Fig. 2 .
- the stationary cascade 7 comprising a number of guide blades 1.
- Figure 3 shows only a few of them.
- the guide blades 1 are circularly arranged at the same distance from each other and welded between a hub 8 and a tip ring 9, whereby the hub parts 4 of the guide blades 1 are welded at the hub 8 and the tip parts 5 of the guide blades 1 are welded at the tip ring 9.
- the additional material of the welding bosses 6 reduced the difference in material thickness between the massive hub 8 and massive tip ring 9 with regards to the thin trailing edge 3 of the guide blade 1. Therefore, the risk of burn out of the trailing edge 3 during the welding process could avoid.
- the welding boss 6 is almost or completely melted by the welding procedure.
- the welding boss 6 is calculated advantageous that it is just big/ massive enough to protect the trailing edge 3 to avoid burn out and do not create any additional material which required a reworking of the welding seam such as grinding or cut off to fulfill the flow requirements in the stationary cascade 7.
- the invention can be used generally for hub part 4 and/ or tip part 5 and is applicable for various types of turbomachinery blades or vanes.
- the blades or vanes can be generally prismatic, conical, leaned bowed or any combinations. It is not limited at any special type of turbomachinery.
- the inventive guide blade and the inventive stationary cascade allow for the first time a high quality of welded turbine stationary cascades. Thereby the production costs can be reduced considerably.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Architecture (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
The present invention is related to a guide blade (1) for a turbomachinery, whereby the guide blade (1) comprising a leading edge (2) and a trailing edge (3) which extend from a hub part (4) to a tip part (5) on the guide blade (1). The guide blade (6) has an additional welding boss (6) on the trailing edge (2) avoiding burn out of the trailing edge (2) during welding process. The invention related also to a stationary cascade (7) for a turbomachinery whereby the stationary cascade (7) is built with inventive guide blades (1).
Description
- The present invention related to a guide blade for a turbomachinery, whereby the guide blade comprising a leading edge and a trailing edge which extend from a hub part to a tip part of the guide blade. The present invention related also to a stationary cascade for a turbomachinery, comprising a hub and a tip ring and a number of guide blades which are welded between the hub and the tip ring, whereby the hub parts of the guide blades are welded at the hub and the tip parts of the guide blades are welded at the tip ring.
- Stationary cascades according to the state of the art, comprising a hub and a tip ring and a number of guide blades. The guide blades are fixed at the hub and the tip ring. To fix the guide blade at the tip ring, the tip ring has a hole which shape is similar to the guide blade profile, so that the guide blade could plug into the hole and fixed by a pin. This solution is probably shown in
DE 195 47 653 C2 . A disadvantage of such a solution is that for each guide blade an own profiled hole is necessary which make this solution complicate and expensive. - A cheaper solution is, to fix the guide blade by a welding process between the hub and the tip ring. Due to the very thin thickness of the trailing edge of the guide blade compared to thickness of the hub and the tip ring there is a technical problem during the welding process. The high temperature of the welding process and the thin thickness of the trailing edge lead to a so called "burn out" of the material of the trailing edge which lead in the worst case to a destruction of the guide blade.
- It is object of the present invention to solve aforesaid problems provide a cheaper stationary cascade.
- Aforesaid object is solved by a guide blade to
independent claim 1 and a stationary cascade toindependent claim 3. - Advantageous embodiments of the invention, which are used individually or in combination with each other, are subject of the dependent claims, the description and the drawings.
- The inventive guide blade for a turbomachinery, whereby the guide blade comprising a leading edge and a trailing edge which extend from a hub part to a tip part of the guide blade is characterized in that, an additional welding boss is designed on the trailing edge. The welding boss leads to a thickening of the trailing edge, so that the trailing edge is protected for a burn out while welding.
- An embodiment of the guide blade is characterized in that the additional welding boss is arranged only at the hub part and/or tip part of the guide blade. The guide blade will be welded only with the hub part to a hub and the tip part to a tip ring, so that only the welding zone should be thickening. Arranging the welding boss only in these zones the weight of the guide blade could be reduced and the flow over the guide blades will not be disturbed.
- The inventive stationary cascade for a turbomachinery, comprising a hub and a tip ring and a number of guide blades which are welded between the hub and the tip ring, whereby the hub parts of the guide blades are welded at the hub and the tip parts of the guide blades are welded at the tip ring, is characterized in that the guide blades are guide
1 or 2.blades according claim
The welding boss allows by thickening at least the welding zone at the hub part and/or tip part of the guide blade the welding without a risk of burn out and destruction of the trailing edge. - An embodiment of the stationary cascade is characterized in that the welding boss is almost or completely melted by a welding procedure and protects the shape of the trailing edge from being destroyed by overheating through the welding procedure. The welding boss is dimensioned in that way, that the boss is generally melt by the welding procedure and is just big enough to protect the trailing edge and do not create any additional material which had to be reworked to keep the required designed channel for a media flow. This simplified the manufacturing and reduced the manufacturing time which leads to a cheaper stationary cascade.
- The present invention is further described with respect to the accompanying figures. The figures schematically show:
- Fig. 1:
- An inventive guide blade
- Fig. 2:
- An inventive stationary cascade
-
Figure 1 shows aninventive guide blade 1. Theguide blade 1 comprising a leadingedge 2 and atrailing edge 3. The leadingedge 2 and thetrailing edge 3 extend from ahub part 4 to atip part 5 of theguide blade 1. Theguide blade 1 is usually used to build a stationary cascade 7 for a turbomachinery which will show and described inFig. 2 . The stationary cascade 7 comprising a number ofguide blades 1. Figure 3 shows only a few of them. Theguide blades 1 are circularly arranged at the same distance from each other and welded between ahub 8 and atip ring 9, whereby thehub parts 4 of theguide blades 1 are welded at thehub 8 and thetip parts 5 of theguide blades 1 are welded at thetip ring 9. - Due to the extremely thin thickness of the
trailing edge 3 there is only very less material at thetrailing edge 3. To avoid a burn out of thetrailing edge 3 during the welding process based on the difference in the material thickness between themassive hub 8 andmassive tip ring 9 with regards to the thintrailing edge 3 of theguide blade 1,additional welding bosses 6 are designed on thetrailing edge 3. Theadditional welding bosses 6 are only designed in the welding zones at thehub part 4 and thetip part 6 of theguide blade 1, so that the media flow will be disturbed as less as possible. In principle thewelding bosses 6 could also extend over the wholetrailing edge 3. - The additional material of the
welding bosses 6 reduced the difference in material thickness between themassive hub 8 andmassive tip ring 9 with regards to the thintrailing edge 3 of theguide blade 1. Therefore, the risk of burn out of thetrailing edge 3 during the welding process could avoid. Thewelding boss 6 is almost or completely melted by the welding procedure. Thewelding boss 6 is calculated advantageous that it is just big/ massive enough to protect thetrailing edge 3 to avoid burn out and do not create any additional material which required a reworking of the welding seam such as grinding or cut off to fulfill the flow requirements in the stationary cascade 7. - The invention can be used generally for
hub part 4 and/ ortip part 5 and is applicable for various types of turbomachinery blades or vanes. The blades or vanes can be generally prismatic, conical, leaned bowed or any combinations. It is not limited at any special type of turbomachinery. - The inventive guide blade and the inventive stationary cascade allow for the first time a high quality of welded turbine stationary cascades. Thereby the production costs can be reduced considerably.
Claims (4)
- Guide blade (1) for a turbomachinery, whereby the guide blade (1) comprising a leading edge (2) and a trailing edge (3) which extend from a hub part (4) to a tip part (5) of the guide blade (1)
characterized in
that an additional welding boss (6) is designed on the trailing edge (3). - Guide blade (1) according claim 1
characterized in
that the additional welding boss (6) is arranged only at the hub part (4) and/or tip part (5) of the guide blade (1). - Stationary cascade (7) for a turbomachinery, comprising a hub (8) and a tip ring (9) and a number of guide blades (1) which are welded between the hub (8) and the tip ring (9), whereby the hub parts (4) of the guide blades (1) are welded at the hub (8) and the tip parts (5) of the guide blades (1) are welded at the tip ring (9),
characterized in
that the guide blades (1) are guide blades (1) according claim 1 or 2. - Stationary cascade (7) according claim 3
characterized in
that the welding boss (6) is completely melted by a welding procedure and protect shape of the trailing edge (3) from being destroyed by overheating through the welding procedure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP19162485.7A EP3708774A1 (en) | 2019-03-13 | 2019-03-13 | Guide blade and stationary cascade for a turbomachinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP19162485.7A EP3708774A1 (en) | 2019-03-13 | 2019-03-13 | Guide blade and stationary cascade for a turbomachinery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP3708774A1 true EP3708774A1 (en) | 2020-09-16 |
Family
ID=65801976
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19162485.7A Withdrawn EP3708774A1 (en) | 2019-03-13 | 2019-03-13 | Guide blade and stationary cascade for a turbomachinery |
Country Status (1)
| Country | Link |
|---|---|
| EP (1) | EP3708774A1 (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19547653C2 (en) | 1995-12-20 | 1999-08-19 | Abb Patent Gmbh | Guide device for a turbine with a guide vane carrier and method for producing this guide device |
| JP2005146859A (en) * | 2003-11-11 | 2005-06-09 | Mitsubishi Heavy Ind Ltd | Impeller and method for manufacturing the same |
| CN103480973A (en) * | 2013-09-22 | 2014-01-01 | 中国东方电气集团有限公司 | Three-stage cold metal transfer welding method for steam turbine hollow static blades |
| EP2985426A1 (en) * | 2014-08-12 | 2016-02-17 | Siemens Aktiengesellschaft | Blade device for a turbine and corresponding manufacturing method |
| DE102015212933A1 (en) * | 2015-07-10 | 2017-01-12 | Siemens Aktiengesellschaft | Guide device for a turbine stage |
| EP3282130A1 (en) * | 2016-08-10 | 2018-02-14 | Siemens Aktiengesellschaft | Layer system, impeller, method to produce |
-
2019
- 2019-03-13 EP EP19162485.7A patent/EP3708774A1/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19547653C2 (en) | 1995-12-20 | 1999-08-19 | Abb Patent Gmbh | Guide device for a turbine with a guide vane carrier and method for producing this guide device |
| JP2005146859A (en) * | 2003-11-11 | 2005-06-09 | Mitsubishi Heavy Ind Ltd | Impeller and method for manufacturing the same |
| CN103480973A (en) * | 2013-09-22 | 2014-01-01 | 中国东方电气集团有限公司 | Three-stage cold metal transfer welding method for steam turbine hollow static blades |
| EP2985426A1 (en) * | 2014-08-12 | 2016-02-17 | Siemens Aktiengesellschaft | Blade device for a turbine and corresponding manufacturing method |
| DE102015212933A1 (en) * | 2015-07-10 | 2017-01-12 | Siemens Aktiengesellschaft | Guide device for a turbine stage |
| EP3282130A1 (en) * | 2016-08-10 | 2018-02-14 | Siemens Aktiengesellschaft | Layer system, impeller, method to produce |
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