CN112439876A - Method for manufacturing gas outlet edge of stationary blade of hollow blade of gas turbine - Google Patents
Method for manufacturing gas outlet edge of stationary blade of hollow blade of gas turbine Download PDFInfo
- Publication number
- CN112439876A CN112439876A CN202011318906.XA CN202011318906A CN112439876A CN 112439876 A CN112439876 A CN 112439876A CN 202011318906 A CN202011318906 A CN 202011318906A CN 112439876 A CN112439876 A CN 112439876A
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- China
- Prior art keywords
- blade
- edge
- tail edge
- core
- air outlet
- 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.)
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/02—Sand moulds or like moulds for shaped castings
- B22C9/04—Use of lost patterns
- B22C9/043—Removing the consumable pattern
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/10—Cores; Manufacture or installation of cores
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/22—Moulds for peculiarly-shaped castings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H1/00—Electrical discharge machining, i.e. removing metal with a series of rapidly recurring electrical discharges between an electrode and a workpiece in the presence of a fluid dielectric
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H9/00—Machining specially adapted for treating particular metal objects or for obtaining special effects or results on metal objects
- B23H9/14—Making holes
Abstract
The invention relates to the technical field of gas turbine hollow blade stationary blade processing, and particularly discloses a gas turbine hollow blade stationary blade gas outlet edge manufacturing method; the method specifically comprises the following steps: processing a mold core; the core comprises a core body provided with a core front edge and a core tail edge, wherein the distance from the core tail edge to a cold air outlet area of the blade tail edge is A; a is more than or equal to 0.5 and less than or equal to 1.5 mm; fine casting of the blade; processing a tail edge air outlet edge cooling structure; on the basis that the shape of the hollow stationary blade is not changed, communicating a tail edge cold air outlet region with a blade internal cavity by using an electric spark puncher, and processing a complete tail edge air outlet edge cooling structure; finishing the processing; according to the invention, the structure of the core tail edge is adjusted, and the pure precision casting method is replaced by a method combining an electric spark processing technology and precision casting to manufacture the blade, so that the process flow for manufacturing the hollow stationary blade is greatly optimized on the premise of effectively ensuring the integrity of the tail edge cooling structure, and the qualified rate of blade manufacturing is improved.
Description
Technical Field
The invention relates to the technical field of machining of hollow blades and stationary blades of a combustion engine, in particular to a method for manufacturing an air outlet edge of a hollow blade and stationary blade of a combustion engine.
Background
The stationary blade of the gas turbine is a core part of the gas turbine, converts the internal energy of a working medium into kinetic energy, and then impacts the movable blade to push the rotor to rotate to output shaft work. The turbine stator blade is subjected to high-temperature and high-speed gas impact, the working environment is extremely severe, and the turbine stator blade needs to be effectively cooled in order to ensure the safe operation of the blade and improve the efficiency of a combustion engine. The turbine blade cooling mode mainly has internal cooling and external cooling, and internal cooling is the hollow blade who designs turbine blade for having complicated inner structure, and this kind of blade is made, the processing degree of difficulty is big, generally adopts the mode of smart casting to make, and the smart casting flow is: core making → wax pressing and assembling → shell making → dewaxing and roasting → pouring → core removing → heat treatment.
Production practice proves that when the hollow stator blade is manufactured by adopting a traditional precision casting mode, the following problems are easy to occur:
1. because the thickness of the air outlet edge of the hollow blade is very thin, the problems of insufficient pouring, flash and the like can occur during the processing by adopting a casting mode, the qualification rate of the cast blade is greatly reduced, and electric processing is required to be carried out in the processing link after precision casting so as to remove burrs, flash and the like, so that the manufacturing link and the period of the blade are increased, and the large-scale production of the hollow blade of the turbine is not facilitated.
2. The hollow blade needs a core as a support in the manufacturing process, the core of the hollow blade comprises a front edge, a pressure surface, a suction surface, a tail edge, an insert and the like, and the mass of the core often determines the mass of the blade. In order to ensure the integrity of the cooling structure of the tail edge of the blade, the tail edge part of the core needs to be made thin and long, but the structure causes the core to be extremely easy to crack, defect and even break in the manufacturing and later use processes, which greatly increases the difficulty of blade manufacturing and reduces the qualification rate of blade manufacturing.
Disclosure of Invention
The invention aims to solve the technical problem of providing a method for manufacturing the gas outlet edge of the hollow stator blade of the gas turbine, which adjusts the structure of the tail edge of a core, replaces a pure precision casting method to manufacture the blade by combining an electric spark processing technology and precision casting, greatly optimizes the process flow for manufacturing the hollow stator blade and improves the qualification rate of blade manufacture on the premise of effectively ensuring the integrity of the cooling structure of the tail edge.
The technical problem to be solved by the invention is as follows:
a manufacturing method of a gas outlet edge of a hollow blade fixed blade of a combustion engine specifically comprises the following steps:
processing a mold core; the mold core comprises a mold core body provided with a mold core front edge and a mold core tail edge, wherein the distance between the mold core tail edge and the gas outlet edge of the tail edge is A; a is more than or equal to 0.5 and less than or equal to 1.5 mm;
fine casting of the blade; the blade comprises a blade body provided with a blade front edge and a blade tail edge, and a tail edge cold air outlet area is arranged on the blade tail edge;
processing a tail edge air outlet edge cooling structure; on the basis that the shape of the hollow stationary blade is not changed, communicating a tail edge cold air outlet region with a blade internal cavity by using an electric spark puncher, and processing a complete tail edge air outlet edge cooling structure;
and finishing the processing.
In the prior art, the core tail edge part in the core penetrates through the blade tail edge and is manufactured in a precision casting mode at one time, wherein the core tail edge is thin and long along with the change of the blade tail edge part; in contrast, the tail edge part of the core does not penetrate through the tail edge of the blade any more, so that the core can only be arranged in the internal cavity of the blade, and the design can effectively avoid the fracture of the tail edge of the core; and then carrying out precision casting on the blade, wherein the contour and the size of the precisely cast blade are the same as those of the blade in the prior art, and the difference is that the tail edge cold air outlet area is not communicated with the internal cavity of the blade, and then, a tail edge groove is machined in an electric spark machining mode to communicate the tail edge groove and the internal cavity of the blade, so that the hollow blade stationary blade with the same structure as that in the prior art is finally obtained.
The manufacturing method can effectively avoid the phenomenon that the finally processed and manufactured product does not meet the requirements due to the breakage of the mold core, and the yield of the hollow blade stationary blade processing and manufacturing can be effectively improved.
In some possible embodiments, a is 1.0 mm.
In some possible embodiments, the blade is precision cast, in particular:
manufacturing a wax mould by using the core, and trimming wax and assembling trees;
making a shell on the basis of a wax mould, burning the wax at high temperature, and baking the mould shell;
and (5) casting the static blade, demolding, removing a mold core and finishing processing.
In some possible embodiments, the tail edge cold air outlet area is communicated with the blade inner cavity by using an electric spark drilling machine, and a complete tail edge air outlet edge cooling structure is machined; the method specifically comprises the following steps:
step S1: selecting electrode materials, and designing the shape and size of the electrode;
step S2, workpiece preparation and workpiece correction positioning;
step S3: and (6) processing.
In some possible embodiments, the core is a ceramic core.
In some possible embodiments, the method further comprises performing a heat treatment after machining the complete trailing edge outlet edge cooling structure.
Compared with the prior art, the invention has the beneficial effects that:
the core tail edge structure is optimally designed, the length of the core tail edge is reduced, the difficulty of core manufacturing is reduced, the core manufacturing yield is improved, the core manufacturing period is shortened, the core production cost is reduced, and the technical problem of mass production of hollow stationary blades is solved;
according to the invention, under the condition that the tail edge of the core is shortened, the electric spark machining process is adopted to machine the complete cooling structure of the air outlet edge of the tail edge of the blade, compared with the pure precision casting manufacturing, under the condition of ensuring the completeness of the tail edge cooling structure, the problems of insufficient pouring, flash and the like can be effectively reduced, the yield of the hollow stator blade production is greatly improved, the production cost is reduced, the production period is shortened, the mass production of the hollow stator blade is facilitated, and the invention has wide application value.
Drawings
FIG. 1 is a schematic view of the core and vane construction of the present invention;
FIG. 2 is a schematic view of the relative positions of the core trailing edge and the vane trailing edge of the present invention;
wherein: 1. a core; 11. a core tail edge; 2. a blade; 21. a trailing edge of the blade; 211. a trailing edge cold air outlet region.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
In the description of the embodiments of the present application, the meaning of "a plurality" means two or more unless otherwise specified. For example, the plurality of positioning posts refers to two or more positioning posts.
The invention is further illustrated with reference to the following figures and examples.
The invention is realized by the following technical scheme, as shown in figures 1 and 2,
a manufacturing method of a gas outlet edge of a hollow blade fixed blade of a combustion engine specifically comprises the following steps:
processing a mold core 1; the mold core 1 comprises a mold core 1 body provided with a mold core 1 front edge and a mold core tail edge 11, wherein the distance between the mold core tail edge 11 and the tail edge air outlet edge is A; a is more than or equal to 0.5 and less than or equal to 1.5 mm;
fine casting of the blade 2; the blade 2 comprises a blade 2 body provided with a blade 2 front edge and a blade trailing edge 21, and a trailing edge cold air outlet region 211 is arranged on the blade trailing edge 21;
processing a tail edge air outlet edge cooling structure; on the basis that the shape of the hollow stationary blade is not changed, a tail edge groove is machined at a position between a hollow tail edge cold air outlet region 211 and a blade 2 internal cavity by using an electric spark puncher, so that the blade 2 internal cavity is communicated with the tail edge cold air outlet region 211, and a complete tail edge air outlet edge cooling structure is machined;
and finishing the processing.
In the prior art, the part of the inner cavity of the blade 2 is filled with a casting core 1, a wax mold serves as an entity, a shell is fixedly used outside the wax mold, the wax mold is melted and poured into high-temperature liquid alloy, and casting is finished; in the casting process, the core tail edge 11 in the core 1 penetrates through the blade tail edge 21 and is processed in a precision casting mode at one time, the blade 2 at the tail edge groove is extremely thin due to the fact that the groove of the blade tail edge 21 is very small, the core tail edge 11 is thin and long along with the change of the blade tail edge 21, and the thin and long structure is extremely easy to crack, defect and even fracture in the manufacturing and later-stage use processes, so that the manufacturing difficulty of the blade 2 is greatly increased, and the manufacturing yield of the blade 2 is reduced;
in contrast, in the invention, the core tail edge 11 part does not pass through the blade tail edge 21 any more, so that the core 1 can only be arranged in the inner cavity of the blade 2, and the design can effectively avoid the fracture of the core tail edge 11; and then, carrying out precision casting on the blade 2, wherein the profile and the size of the precisely cast blade 2 are the same as those of the blade 2 in the prior art, and the difference is that a tail edge cold air outlet region 211 is not communicated with an internal cavity of the blade 2, and the two are communicated by adopting an electric spark machining mode, so that the hollow blade 2 static blade with the same structure as that in the prior art is finally obtained.
The structure of the stator blade of the hollow blade 2 is known, the position of the tail edge cold air outlet area 211 is also known, and for the reason, the distance between the tail edge 11 of the core and the tail edge cold air outlet area 211 is A, and A is more than or equal to 0.5 and less than or equal to 1.5 mm; that is, as shown in FIG. 2, the distance between the core tail edge 11 and the side of the tail edge gas outlet edge close to the inner cavity of the blade 2 is A, and A is more than or equal to 0.5mm and less than or equal to 1.5 mm.
The hollow blade 2 stationary blade comprises a pressure surface and a suction surface, the core tail edge 11 is trimmed to the position, so that the pressure surface tail edge and the suction surface tail edge can be supported, and the forming stability of the blade 2 is effectively improved in the process of carrying out the precision casting of the blade 2. In order to enable the suction surface and the pressure surface to be supported more firmly and reliably, the distance between the tail edge 11 of the mold core and the air outlet edge of the tail edge is A, and A is more than or equal to 0.5 and less than or equal to 1.5 mm; therefore, the original problem that the pouring is incomplete or the flash appears when A is less than 0.5mm can be effectively avoided. In the test process, when the distance A is more than 1.5mm, the blade 2 is of a curved surface structure, so that the processing difficulty of the electric spark puncher is greatly increased and the precision is difficult to control when the electric spark puncher is used for processing a tail edge groove; the processing cost increases and the processing cycle becomes longer.
In some possible embodiments, preferably, a is 1.0 mm.
In some possible embodiments, the blade 2 is precision cast, in particular:
manufacturing a wax mould by using the core 1, and trimming wax and assembling trees;
making a shell on the basis of a wax mould, burning the wax at high temperature, and baking the mould shell;
and (5) casting the static blade, demolding, removing the mold core 1 and finishing processing.
In some possible embodiments, the tail edge cold air outlet region 211 is communicated with the internal cavity of the blade 2 by using an electric spark drilling machine, so that a complete tail edge outlet edge cooling structure is machined; the method specifically comprises the following steps:
step S1: preparing an electrode;
step S11: selecting an electrode material according to a workpiece material and a processing requirement;
step S12: designing the shape and size of the electrode according to the structure and size of the tail edge groove, and processing the working electrode;
step S13, clamping the electrode by adopting a clamping tool;
step S2, workpiece preparation and workpiece correction positioning; removing the allowance of the workpiece, carrying out heat treatment on the workpiece, clamping the workpiece by adopting a clamping mechanism, and correcting and positioning the workpiece;
step S3: and (4) processing a tail edge groove. For the machining of the tail edge groove by using the electric spark drilling machine, the specific machining process is the prior art, and the machining process is not described in detail herein.
In some possible embodiments, the core 1 is a ceramic core.
In some possible embodiments, the method further comprises performing a heat treatment after machining the complete trailing edge outlet edge cooling structure.
The foregoing detailed description of the embodiments of the present application has been presented, and specific examples have been applied in the present application to explain the principles and implementations of the present application, and the above description of the embodiments is only used to help understand the method and the core ideas of the present application; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.
Claims (6)
1. The manufacturing method of the gas outlet edge of the hollow blade stationary blade of the gas turbine is characterized in that: the method specifically comprises the following steps:
processing a mold core; the mold core comprises a mold core body provided with a mold core front edge and a mold core tail edge, wherein the distance between the mold core tail edge and the air outlet edge of the blade tail edge is A; a is more than or equal to 0.5 and less than or equal to 1.5 mm;
fine casting of the blade; the blade comprises a blade body provided with a blade front edge and a blade tail edge, and a tail edge cold air outlet area is arranged on the blade tail edge;
processing a tail edge air outlet edge cooling structure; on the basis that the shape of the hollow stationary blade is not changed, communicating a tail edge cold air outlet region with a blade internal cavity by using an electric spark puncher, and processing a complete tail edge air outlet edge cooling structure;
and finishing the processing.
2. The method for manufacturing the gas outlet edge of the hollow vane of the combustion engine as claimed in claim 1, wherein: the A is 1.0 mm.
3. The method for manufacturing the gas outlet edge of the hollow vane of the combustion engine as claimed in claim 1, wherein: the blade precision casting specifically comprises the following steps:
manufacturing a wax mould by using the core, and trimming wax and assembling trees;
making a shell on the basis of a wax mould, burning the wax at high temperature, and baking the mould shell;
and (5) pouring the stationary blade, demolding, removing a mold core and finishing machining and casting.
4. The method for manufacturing the gas outlet edge of the hollow vane of the combustion engine as claimed in claim 1, wherein: the tail edge cold air outlet area is communicated with the blade inner cavity by using an electric spark puncher, and a complete tail edge air outlet edge cooling structure is processed; the method specifically comprises the following steps:
step S1: selecting electrode materials, and designing the shape and size of the electrode;
step S2, workpiece preparation and workpiece correction positioning;
step S3: and (6) processing.
5. The method for manufacturing the gas outlet edge of the hollow vane of the combustion engine as claimed in claim 1, wherein: the core is a ceramic core.
6. The method for manufacturing the gas outlet edge of the hollow vane of the combustion engine as claimed in claim 1, wherein: and further comprises the step of carrying out heat treatment after the complete tail edge air outlet edge cooling structure is processed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011318906.XA CN112439876A (en) | 2020-11-23 | 2020-11-23 | Method for manufacturing gas outlet edge of stationary blade of hollow blade of gas turbine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011318906.XA CN112439876A (en) | 2020-11-23 | 2020-11-23 | Method for manufacturing gas outlet edge of stationary blade of hollow blade of gas turbine |
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| CN112439876A true CN112439876A (en) | 2021-03-05 |
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| CN202011318906.XA Pending CN112439876A (en) | 2020-11-23 | 2020-11-23 | Method for manufacturing gas outlet edge of stationary blade of hollow blade of gas turbine |
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Citations (8)
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|---|---|---|---|---|
| CN1963156A (en) * | 2003-01-31 | 2007-05-16 | 联合工艺公司 | Turbine blade |
| CN1995708A (en) * | 2005-12-05 | 2007-07-11 | 通用电气公司 | Blade with parallel serpentine cooling channels |
| CN101131097A (en) * | 2006-08-21 | 2008-02-27 | 通用电气公司 | Cascade tip baffle airfoil |
| US20140199177A1 (en) * | 2013-01-09 | 2014-07-17 | United Technologies Corporation | Airfoil and method of making |
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| CN107127301A (en) * | 2016-02-29 | 2017-09-05 | 通用电气公司 | Utilize the casting of the first hardware and the second hardware |
| CN107931761A (en) * | 2017-11-16 | 2018-04-20 | 陕西启源科技发展有限责任公司 | Electric-spark drilling processing method |
| US20200102841A1 (en) * | 2018-10-01 | 2020-04-02 | United Technologies Corporation | Multi-walled airfoil core |
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2020
- 2020-11-23 CN CN202011318906.XA patent/CN112439876A/en active Pending
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| CN1963156A (en) * | 2003-01-31 | 2007-05-16 | 联合工艺公司 | Turbine blade |
| CN1995708A (en) * | 2005-12-05 | 2007-07-11 | 通用电气公司 | Blade with parallel serpentine cooling channels |
| CN101131097A (en) * | 2006-08-21 | 2008-02-27 | 通用电气公司 | Cascade tip baffle airfoil |
| US20140199177A1 (en) * | 2013-01-09 | 2014-07-17 | United Technologies Corporation | Airfoil and method of making |
| CN107127300A (en) * | 2016-02-29 | 2017-09-05 | 通用电气公司 | Utilize the casting of alternation core component |
| CN107127301A (en) * | 2016-02-29 | 2017-09-05 | 通用电气公司 | Utilize the casting of the first hardware and the second hardware |
| CN107931761A (en) * | 2017-11-16 | 2018-04-20 | 陕西启源科技发展有限责任公司 | Electric-spark drilling processing method |
| US20200102841A1 (en) * | 2018-10-01 | 2020-04-02 | United Technologies Corporation | Multi-walled airfoil core |
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| 于建华等: "航空发动机加工装备的性能需求与验收关键技术", 《世界制造技术与装备市场》 * |
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