Manufacturing thin-walled castings utilizing adaptive machining

Patent metadata

Field	Value
Publication number	US-11319814-B2
Application number	US-201916403208-A
Country	US
Kind code	B2
Filing date	May 3, 2019
Priority date	May 3, 2019
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

A method of manufacturing a casting is provided and includes establishing desired dimensions of a nominal casting, executing a casting process to produce multiple actual castings with each of the multiple actual castings having respective dimensions that differ from each other and from the desired dimensions of the nominal casting and engaging one or more tools to adaptively machine, without rigidly-programmed toolpaths, each of the multiple actual castings to reduce the respective differences between the actual dimensions of each of the multiple actual castings and the desired dimensions.

First claim

What is claimed is:

1. A method of manufacturing a casting, the method comprising:
establishing desired dimensions of a nominal casting;
executing a casting process to produce multiple actual castings with each of the multiple actual castings having respective dimensions that differ from each other and from the desired dimensions of the nominal casting; and
engaging one or more tools to adaptively machine, without rigidly-programmed toolpaths, each of the multiple actual castings to reduce the respective differences between the actual dimensions of each of the multiple actual castings and the desired dimensions,
wherein:
actual dimensions of each of the multiple castings exceed or are less than the desired dimensions and the engaging of the one or more tools, without rigidly-programmed toolpaths, comprises engaging a cutting tool to reduce the actual dimensions of each of the multiple actual castings exceeding the desired dimensions and engaging an additive manufacturing tool to increase the actual dimensions of each of the multiple castings that are less than the desired dimensions, and
the engaging of the cutting tool and the additive manufacturing tool comprises preparing by importing net-state models of the nominal casting and creating three-dimensional scans of exemplary workpieces, identifying registration, best-fit point and surface references, creating an index of features to identify and setting adaptive machining rules.

2. The method according to claim 1 , wherein the nominal casting has a size and shape of a turbine airfoil and each of the multiple actual castings has a trailing edge which is at least one of thicker than and offset from a trailing edge of the nominal casting.

3. The method according to claim 1 , wherein the nominal casting has a size and shape of a turbine airfoil and each of the multiple actual castings has an irregular trailing edge which is thicker than a trailing edge of the nominal casting.

4. The method according to claim 1 , wherein the nominal casting has a size and shape of a turbine airfoil and each of the multiple actual castings has a trailing edge which is at least one of canted and bowed as compared to a trailing edge of the nominal casting.

5. The method according to claim 1 , wherein the executing of the adaptive machining comprises:
scanning each of the multiple actual castings;
creating difference maps between the nominal casting and each of the multiple actual castings in accordance with the registration, best-fit point and surface references;
defining subtractive and additive operations relative to each of the multiple actual castings in accordance with the index of features; and
programming the one or more tools to execute the subtractive and additive operations in accordance with the adaptive machining rules.

6. The method according to claim 1 , wherein the executing of the adaptive machining is deliberately executed such that the actual dimensions of each of the multiple castings differ from the desired dimensions in a manner that is correctable by the one or more tools.

7. A computer-implemented method of manufacturing a casting, the method comprising:
establishing desired dimensions of multiple portions of a nominal turbine airfoil casting;
executing a casting process to produce multiple actual turbine airfoil castings, each of the multiple actual turbine airfoil castings having respective actual dimensions at multiple portions thereof that exceed or are less than the desired dimensions of the multiple portions of the nominal turbine airfoil casting; and
engaging one or more tools to adaptively machine, without rigidly-programmed toolpaths, each of the multiple actual turbine airfoil castings to reduce the respective differences between the actual dimensions at the multiple portions of each of the multiple actual turbine airfoil castings and the desired dimensions of the multiple portions,
wherein:
actual dimensions of each of the multiple castings exceed or are less than the desired dimensions and the engaging of the one or more tools, without rigidly-programmed toolpaths, comprises engaging a cutting tool to reduce the actual dimensions of each of the multiple actual castings exceeding the desired dimensions and engaging an additive manufacturing tool to increase the actual dimensions of each of the multiple castings that are less than the desired dimensions, and
the engaging of the cutting tool and the additive manufacturing tool comprises preparing by importing net-state models of the nominal casting and creating three-dimensional scans of exemplary workpieces, identifying registration, best-fit point and surface references, creating an index of features to identify and setting adaptive machining rules.

8. The computer-implemented method according to claim 7 , wherein:
one of the multiple portions of the nominal turbine airfoil casting is a trailing edge thereof and one of the desired dimensions is a thickness thereof,
one of the multiple portions of each of the multiple actual turbine airfoil castings is a trailing edge thereof and one of the actual dimensions is a thickness thereof, and
the thickness of the trailing edge of each of the multiple actual turbine airfoil castings is at least one of thicker than and offset from the trailing edge of the nominal turbine airfoil casting.

9. The computer-implemented method according to claim 7 , wherein:
one of the multiple portions of the nominal turbine airfoil casting is a trailing edge thereof and one of the desired dimensions is a thickness thereof,
one of the multiple portions of each of the multiple actual turbine airfoil castings is an irregular trailing edge thereof and one of the actual dimensions is a thickness thereof, and
the thickness of the irregular trailing edge of each of the multiple actual turbine airfoil castings is thicker than the trailing edge of the nominal turbine airfoil casting.

10. The computer-implemented method according to claim 7 , wherein:
one of the multiple portions of the nominal turbine airfoil casting is a trailing edge thereof and one of the desired dimensions is at least one of a canting and bowing thereof,
one of the multiple portions of each of the multiple actual turbine airfoil castings is a trailing edge thereof and one of the actual dimensions is at least one of a canting and a bowing thereof, and
the at least one of the canting and the bowing of the trailing edge of each of the multiple actual turbine airfoil castings differs from the at least one of the canting and the bowing of the trailing edge of the nominal turbine airfoil casting.

11. The computer-implemented method according to claim 7 , wherein the executing of the adaptive machining comprises:
scanning each of the multiple actual turbine airfoil castings;
creating difference maps between the nominal turbine airfoil casting and each of the multiple actual turbine airfoil castings in accordance with the registration, best-fit point and surface references;
defining subtractive and additive operations relative to each of the multiple actual turbine airfoil castings in accordance with the index of features; and
programming the one or more tools to execute the subtractive and additive operations in accordance with the adaptive machining rules.

12. The computer-implemented method according to claim 7 , wherein the executing of the adaptive machining is deliberately executed such that the actual dimensions of each of the multiple actual turbine airfoil castings differ from the desired dimensions in a manner that is correctable by the one or more tools.

13. A computer-implemented method of manufacturing a casting, the method comp

Assignees

• United Technologies Corp
• Raytheon Tech Corp

Inventors

• Auxier James Tilsley
• Cofalka Norman W
• Barron Alan C

Classifications

• F01D5/14 Primary

  Form or construction (selecting particular materials, measures against erosion or corrosion F01D5/28) · CPC title

• B22D31/00 Primary

  Cutting-off surplus material, e.g. gates; {Cleaning and working on castings (B22D17/2076 takes precedence)} · CPC title

• B22F10/20

  Direct sintering or melting · CPC title

• F01D5/141

  Shape, i.e. outer, aerodynamic form (F01D5/148 - F01D5/20 take precedence; blade construction F01D5/147) · CPC title

• B22F7/08

  with one or more parts not made from powder {(B22F7/062 takes precedence)} · CPC title