EP1358958A1 - A way to manufacture inserts for steam cooled hot gas path components - Google Patents

A way to manufacture inserts for steam cooled hot gas path components Download PDF

Info

Publication number
EP1358958A1
EP1358958A1 EP20030252630 EP03252630A EP1358958A1 EP 1358958 A1 EP1358958 A1 EP 1358958A1 EP 20030252630 EP20030252630 EP 20030252630 EP 03252630 A EP03252630 A EP 03252630A EP 1358958 A1 EP1358958 A1 EP 1358958A1
Authority
EP
European Patent Office
Prior art keywords
casting
inserts
method
ceramic
hot gas
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.)
Granted
Application number
EP20030252630
Other languages
German (de)
French (fr)
Other versions
EP1358958B1 (en
Inventor
Robert H. Devine
Justin W. Downs
Lance G. Peterson
James M. Placko
Jon C. Schaeffer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Family has litigation
Priority to US131137 priority Critical
Priority to US10/131,137 priority patent/US20030201087A1/en
Application filed by General Electric Co filed Critical General Electric Co
Publication of EP1358958A1 publication Critical patent/EP1358958A1/en
Application granted granted Critical
Publication of EP1358958B1 publication Critical patent/EP1358958B1/en
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=29215557&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP1358958(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application status is Revoked legal-status Critical
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D29/00Removing castings from moulds, not restricted to casting processes covered by a single main group; Removing cores; Handling ingots
    • B22D29/001Removing cores
    • B22D29/002Removing cores by leaching, washing or dissolving
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22CFOUNDRY MOULDING
    • B22C9/00Moulds or cores; Moulding processes
    • B22C9/02Sand moulds or like moulds for shaped castings
    • B22C9/04Use of lost patterns

Abstract

A method for forming inserts for steam cooled hot gas path components involves casting the inserts (10) and laser drilling (14) the cast inserts (10) with the ceramic casting core (12) still in place. Thereafter, the ceramic core (12) is removed through the use of a leachant. By laser drilling (14) the holes (16) with the ceramic core (12) still in place, the ceramic core (12) acts as a backer during the laser drilling (14) which results in more precise drilling of the inserts (10) and reduced processing time.

Description

  • The invention relates to a new way to manufacture inserts for steam cooled hot gas path components.
  • Inserts are required in air and steam cooled nozzles to provide impingement cooling to airfoil walls and ribs. The prior art methods of production of inserts use sheet metal forming operations, including welding and brazing, and electro discharge machining of the holes. The problem with the prior art methods is that the large complicated inserts combined with strict dimensional tolerances result in 3D structures that have a very low yield relative to design specifications.
  • The inventive process casts the inserts to tight tolerance using any ceramic core casting process such as, for example, pressure casting, centrifugal casting, squeeze casting or vacuum casting (also known as counter gravity casting). Counter gravity casting as employed by Hitchiner Manufacturing Co., Inc. of Milford, New Hampshire uses metal dies with a vacuum pour to help fill thin sections of the casting and eliminate porosity. After casting has been completed, the core material is then used as a backer during subsequent drilling operations. Finally, the core is removed by acid leaching and the cast parts are machined, if necessary, to finish specifications.
  • With the inventive manufacturing method certain commercial and performance needs are met. For example, the inventive method facilitates the production of complicated 3D insert geometrics in a Ni-base superalloy with thin walls and tight tolerances. The inventive method also provides for accurate and precise drilling of the cast inserts with improved processing times and fixtures.
  • The inventive method also solves the problems in the prior art by using the ceramic core in the insert casting process to act as a backer for laser drilling. The laser holes then facilitate the use of leachant to quickly remove the core, speeding the manufacturing process.
  • The invention will now be described in greater detail, by way of example, with reference to the drawings, in which:-
  • Figure 1 show a cast insert prior to laser drilling of the insert holes;
  • Figure 2 shows the case insert of Figure 1 after laser drilling of the insert holes but with the ceramic core still in place; and
  • Figure 3 shows the cast and drilled insert immersed in an acid bath for removal of the ceramic core.
  • The inventive method uses, for example, Hitchiner's thin wall casting process to produce the insert geometry from a wax model. The Hitchiner process substitutes counter gravity casting for more conventional casting by, for example, gravity pouring.
  • In the basic investment casting process, wax replicas of the desired castings are produced by injection molding. Depending on the size of the castings, multiple wax replicas may be attached to a central waxed stick, termed a sprue, to thereby form a casting assembly. Thereafter, a ceramic shell is formed around the casting or the casting assembly made up of the multiple wax replicas of the desired castings. Next, the ceramic is dried and the wax is melted out creating a negative impression of the casting assembly within the ceramic shell.
  • If using the basic casting process, the casting shell is filled with molten metal by gravity pouring. Conversely, in the Hitchiner counter gravity process the ceramic casting shell is placed within a vacuum and dipped into a hot metal melt which is then siphoned up around and into the ceramic casting assembly. After the metal is allowed to solidify on the ceramic casting the vacuum is released and residual metal flows back in to the melt. Figure 1 schematically shows a cast insert 10 with ceramic core 12 shown in place by dotted lines. Also shown is laser drilling apparatus 14 prior to the drilling process.
  • Preferably, the cast inserts are made from IN625 (Ni-base superalloy). After the insert are cast into the desired geometry, the ceramic core is not immediately leached out. Instead the casting is put in a fixture for laser drilling holes with the ceramic core still in place. The casting tolerances are such that a fixture can handle a production run without a lot of rework.
  • The insert is then laser drilled with the ceramic core as a backer. The backer stops backwall strikes and will act as a breakthrough detector. Figure 2 schematically shows insert 10 after holes 16 have been drilled by laser drilling apparatus 14.
  • After the large number of holes (∼300 holes/insert) are drilled with laser precision, the ceramic core is leached out with suitable caustics. Figure 3 schematically shows ceramic 12 being removed by immersing cast insert 10 in acid bath 18.
  • Another advantage of the inventive method is the reduction in the number of heat treatments that the part goes through relative to current state of the art processing. Reducing heat treatments reduces the amount of distortion caused by residual stresses and results in higher quality. The invention will produce inserts and baffles for hot gas path hardware at a greater level of performance and yield.
  • While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims (7)

  1. A method of forming inserts (10) for steam cooled hot gas path components in a turbine, said method comprising:
    casting the geometrical configuration of the insert(10); and
    laser drilling impingement holes (16) in the cast insert (10) without removing a ceramic casting core (12) of the cast insert (10).
  2. A method as claimed in claim 1, wherein the ceramic casting core (12) is removed by leachant.
  3. A method as claimed in claim 1 or 2, wherein said casting (12) comprises pressure casting.
  4. A method as claimed in claim 1 or 2, wherein said casting (12) comprises centrifugal casting.
  5. A method as claimed in claim 1 or 2, wherein said casting (12) comprises squeeze casting.
  6. A method as claimed in claim 1 or 2, wherein said casting (12) comprises counter gravity casting.
  7. A method as claimed in any preceding claim 1 or 2, wherein the inserts (10) are made of a Ni-base superalloy.
EP20030252630 2002-04-25 2003-04-25 A way to manufacture inserts for steam cooled hot gas path components Revoked EP1358958B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US131137 2002-04-25
US10/131,137 US20030201087A1 (en) 2002-04-25 2002-04-25 Way to manufacture inserts for steam cooled hot gas path components

Publications (2)

Publication Number Publication Date
EP1358958A1 true EP1358958A1 (en) 2003-11-05
EP1358958B1 EP1358958B1 (en) 2005-03-30

Family

ID=29215557

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20030252630 Revoked EP1358958B1 (en) 2002-04-25 2003-04-25 A way to manufacture inserts for steam cooled hot gas path components

Country Status (5)

Country Link
US (1) US20030201087A1 (en)
EP (1) EP1358958B1 (en)
JP (1) JP2004003470A (en)
KR (1) KR20030084716A (en)
DE (1) DE60300436T2 (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2471615A1 (en) * 2010-12-30 2012-07-04 Rolls-Royce Corporation System, method and apparatus for leaching cast components
US9579714B1 (en) 2015-12-17 2017-02-28 General Electric Company Method and assembly for forming components having internal passages using a lattice structure
CN106825503A (en) * 2017-03-15 2017-06-13 江苏钜源机械有限公司 The negative-pressure los mould casting method of locomotive engine water cooling cylinder
US9968991B2 (en) 2015-12-17 2018-05-15 General Electric Company Method and assembly for forming components having internal passages using a lattice structure
US9987677B2 (en) 2015-12-17 2018-06-05 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US10046389B2 (en) 2015-12-17 2018-08-14 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US10099276B2 (en) 2015-12-17 2018-10-16 General Electric Company Method and assembly for forming components having an internal passage defined therein
US10099284B2 (en) 2015-12-17 2018-10-16 General Electric Company Method and assembly for forming components having a catalyzed internal passage defined therein
US10099283B2 (en) 2015-12-17 2018-10-16 General Electric Company Method and assembly for forming components having an internal passage defined therein
US10118217B2 (en) 2015-12-17 2018-11-06 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US10137499B2 (en) 2015-12-17 2018-11-27 General Electric Company Method and assembly for forming components having an internal passage defined therein
US10150158B2 (en) 2015-12-17 2018-12-11 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US10286450B2 (en) 2016-04-27 2019-05-14 General Electric Company Method and assembly for forming components using a jacketed core
US10335853B2 (en) 2016-04-27 2019-07-02 General Electric Company Method and assembly for forming components using a jacketed core

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6057778B2 (en) 2013-02-27 2017-01-11 本田技研工業株式会社 Laser processing equipment
EP2971532A4 (en) * 2013-03-15 2016-11-16 United Technologies Corp Additive manufacturing baffles, covers, and dies
US10315248B2 (en) * 2016-11-17 2019-06-11 General Electric Company Methods and apparatuses using cast in core reference features

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3694264A (en) * 1970-09-28 1972-09-26 Stuart L Weinland Core removal
US3858290A (en) * 1972-11-21 1975-01-07 Avco Corp Method of making inserts for cooled turbine blades
GB2105624A (en) * 1981-09-02 1983-03-30 Rolls Royce Turbine blade manufacture
US5465780A (en) * 1993-11-23 1995-11-14 Alliedsignal Inc. Laser machining of ceramic cores
EP0974735A2 (en) * 1998-07-20 2000-01-26 General Electric Company Dimpled impingement baffle

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3694264A (en) * 1970-09-28 1972-09-26 Stuart L Weinland Core removal
US3858290A (en) * 1972-11-21 1975-01-07 Avco Corp Method of making inserts for cooled turbine blades
GB2105624A (en) * 1981-09-02 1983-03-30 Rolls Royce Turbine blade manufacture
US5465780A (en) * 1993-11-23 1995-11-14 Alliedsignal Inc. Laser machining of ceramic cores
EP0974735A2 (en) * 1998-07-20 2000-01-26 General Electric Company Dimpled impingement baffle

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2471615A1 (en) * 2010-12-30 2012-07-04 Rolls-Royce Corporation System, method and apparatus for leaching cast components
US8828214B2 (en) 2010-12-30 2014-09-09 Rolls-Royce Corporation System, method, and apparatus for leaching cast components
US10099276B2 (en) 2015-12-17 2018-10-16 General Electric Company Method and assembly for forming components having an internal passage defined therein
US10150158B2 (en) 2015-12-17 2018-12-11 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US9968991B2 (en) 2015-12-17 2018-05-15 General Electric Company Method and assembly for forming components having internal passages using a lattice structure
US9975176B2 (en) 2015-12-17 2018-05-22 General Electric Company Method and assembly for forming components having internal passages using a lattice structure
US9987677B2 (en) 2015-12-17 2018-06-05 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US10046389B2 (en) 2015-12-17 2018-08-14 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US9579714B1 (en) 2015-12-17 2017-02-28 General Electric Company Method and assembly for forming components having internal passages using a lattice structure
US10099284B2 (en) 2015-12-17 2018-10-16 General Electric Company Method and assembly for forming components having a catalyzed internal passage defined therein
US10099283B2 (en) 2015-12-17 2018-10-16 General Electric Company Method and assembly for forming components having an internal passage defined therein
US10118217B2 (en) 2015-12-17 2018-11-06 General Electric Company Method and assembly for forming components having internal passages using a jacketed core
US10137499B2 (en) 2015-12-17 2018-11-27 General Electric Company Method and assembly for forming components having an internal passage defined therein
US10286450B2 (en) 2016-04-27 2019-05-14 General Electric Company Method and assembly for forming components using a jacketed core
US10335853B2 (en) 2016-04-27 2019-07-02 General Electric Company Method and assembly for forming components using a jacketed core
CN106825503A (en) * 2017-03-15 2017-06-13 江苏钜源机械有限公司 The negative-pressure los mould casting method of locomotive engine water cooling cylinder

Also Published As

Publication number Publication date
EP1358958B1 (en) 2005-03-30
DE60300436T2 (en) 2006-02-09
DE60300436D1 (en) 2005-05-04
JP2004003470A (en) 2004-01-08
KR20030084716A (en) 2003-11-01
US20030201087A1 (en) 2003-10-30

Similar Documents

Publication Publication Date Title
RU2282520C2 (en) Apparatus for casting member of gas turbine engine (variants) and casting core of refractory metal (variants)
EP1381481B1 (en) Multi-wall core and process
US4417381A (en) Method of making gas turbine engine blades
JP2005028455A (en) Investment casting method, and core and die used therein
EP1534451B1 (en) Casting process
JP4516012B2 (en) Casting ceramic core and method
EP0324229B1 (en) Apparatus for supporting a core in a mould
EP0585183B1 (en) Investment casting using core with integral wall thickness control means
US4637449A (en) Component casting
US3595301A (en) Method of making intricate die castings
EP1142658B1 (en) Reinforced ceramic shell molds, and related processes
EP2191910B1 (en) Castings, casting cores, and methods
JP2007061902A (en) Method and apparatus for manufacturing pattern for investment casting, and casting core
AU2005201580B2 (en) Investment casting
EP1854567B1 (en) Contoured metallic casting core
US4384607A (en) Method of manufacturing a blade or vane for a gas turbine engine
US7882884B2 (en) Method for casting core removal
US4434835A (en) Method of making a blade aerofoil for a gas turbine engine
JP2007307618A (en) Method for manufacturing combination investment casting core, and investment casting core
EP2991787B1 (en) Investment casting utilizing flexible wax pattern tool for supporting a ceramic core along its length during wax injection
US7753104B2 (en) Investment casting cores and methods
CA1079026A (en) Mold assembly and method of making the same
US5465780A (en) Laser machining of ceramic cores
EP1607158B1 (en) Process for preparing a turbine stator casing
US4321010A (en) Aerofoil member for a gas turbine engine

Legal Events

Date Code Title Description
AX Request for extension of the european patent to

Extension state: AL LT LV MK

AK Designated contracting states:

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

17P Request for examination filed

Effective date: 20040506

AKX Payment of designation fees

Designated state(s): CH DE FR GB IT LI

AK Designated contracting states:

Kind code of ref document: B1

Designated state(s): CH DE FR GB IT LI

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: CH

Ref legal event code: NV

Representative=s name: SERVOPATENT GMBH

REF Corresponds to:

Ref document number: 60300436

Country of ref document: DE

Date of ref document: 20050504

Kind code of ref document: P

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

26 Opposition filed

Opponent name: SIEMENS AG ABTEILUNG CT IP PG

Effective date: 20051221

ET Fr: translation filed
REG Reference to a national code

Ref country code: CH

Ref legal event code: PFA

Owner name: GENERAL ELECTRIC COMPANY

Free format text: GENERAL ELECTRIC COMPANY#1 RIVER ROAD#SCHENECTADY, NY 12345 (US) -TRANSFER TO- GENERAL ELECTRIC COMPANY#1 RIVER ROAD#SCHENECTADY, NY 12345 (US)

PGFP Postgrant: annual fees paid to national office

Ref country code: IT

Payment date: 20080424

Year of fee payment: 5

PG25 Lapsed in a contracting state announced via postgrant inform. from nat. office to epo

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080425

PGFP Postgrant: annual fees paid to national office

Ref country code: DE

Payment date: 20090429

Year of fee payment: 7

Ref country code: FR

Payment date: 20090417

Year of fee payment: 7

PGFP Postgrant: annual fees paid to national office

Ref country code: CH

Payment date: 20090427

Year of fee payment: 7

PGFP Postgrant: annual fees paid to national office

Ref country code: GB

Payment date: 20090429

Year of fee payment: 7

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

GBPR Gb: patent revoked under art. 102 of the ep convention designating the uk as contracting state

Effective date: 20100226

27W Revoked

Effective date: 20100226

PG25 Lapsed in a contracting state announced via postgrant inform. from nat. office to epo

Ref country code: CH

Free format text: LAPSE BECAUSE OF THE APPLICANT RENOUNCES

Effective date: 20050330

Ref country code: LI

Free format text: LAPSE BECAUSE OF THE APPLICANT RENOUNCES

Effective date: 20050330