US 12,030,158 B2
Smoothing round internal passages of additively manufactured parts using metallic spheres
Henry H. Thayer, Wethersfield, CT (US); and Wendell V Twelves, Glastonbury, CT (US)
Assigned to RTX CORPORATION, Farmington, CT (US)
Filed by RAYTHEON TECHNOLOGIES CORPORATION, Farmington, CT (US)
Filed on Apr. 7, 2023, as Appl. No. 18/297,503.
Application 18/297,503 is a division of application No. 17/477,873, filed on Sep. 17, 2021, granted, now 11,648,642.
Application 17/477,873 is a division of application No. 15/957,873, filed on Apr. 19, 2018, granted, now 11,148,248, issued on Oct. 19, 2021.
Prior Publication US 2023/0264318 A1, Aug. 24, 2023
Int. Cl. B24B 39/02 (2006.01); B33Y 40/20 (2020.01); B33Y 80/00 (2015.01); F01D 25/12 (2006.01); F01D 25/18 (2006.01)
CPC B24B 39/023 (2013.01) [B33Y 40/20 (2020.01); B33Y 80/00 (2014.12); F01D 25/12 (2013.01); F01D 25/18 (2013.01); F05D 2220/32 (2013.01); F05D 2230/50 (2013.01); F05D 2240/12 (2013.01); F05D 2240/30 (2013.01); F05D 2260/20 (2013.01); F05D 2260/98 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A method for smoothing surface roughness within an internal passageway, comprising:
urging a first sphere into a first end of the internal passageway and to a first distance along a first curved portion of a length of the internal passageway, wherein the first sphere has a first sphere diameter greater than or equal to a diameter of the internal passageway;
urging a second sphere into the first end of the internal passageway, wherein the second sphere has a second sphere diameter greater than the first sphere diameter, the second sphere urging the first sphere to a second distance along the first curved portion of the length of the internal passageway;
urging the first sphere along a substantially straight portion of the internal passageway downstream of the first curved portion via the second sphere;
urging the first sphere along a second curved portion of the internal passageway downstream of the substantially straight portion via the second sphere; and
urging the first sphere out of a second end of the internal passageway downstream of the second curved portion via the second sphere,
wherein an inner surface of the internal passageway is smoothed by the first sphere and the second sphere along the length of the internal passageway from the first end to the second end.