SMOOTHING ROUND INTERNAL PASSAGES OF ADDITIVELY MANUFACTURED PARTS USING METALLIC SPHERES

• US 20190321938A1
• Filed: 04/19/2018
• Published: 10/24/2019
• Est. Priority Date: 04/19/2018
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Thayer, Henry H., Twelves, Wendell V.
• Granted Patent: US 11,148,248 B2
• Time in Patent Office: Days
• CPC Class Codes: B24B 39/023 the working tool being composed of a plurality of working rolls or balls
• CPC Class Codes: B33Y 40/20 Post-treatment, e.g. curing, coating or polishing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: F01D 25/12 Cooling
• CPC Class Codes: F01D 25/18 Lubricating arrangements of machines or engines in general F01M
• CPC Class Codes: F01D 5/18 Hollow blades, i.e. blades with cooling or heating channels or cavities structure of hollow blades in general F01D5/147; Heating, heat-insulating or cooling means on blades
• CPC Class Codes: F01D 5/187 Convection cooling
• CPC Class Codes: F01D 9/065 Fluid supply or removal conduits traversing the working fluid flow, e.g. for lubrication-, cooling-, or sealing fluids see also F01D25/16, F01D25/24 and F01D25/26
• CPC Class Codes: F05D 2220/32 in gas turbines
• CPC Class Codes: F05D 2230/20 essentially without removing material
• CPC Class Codes: F05D 2230/50 Building or constructing in particular ways
• CPC Class Codes: F05D 2240/12 Fluid guiding means, e.g. vanes
• CPC Class Codes: F05D 2240/30 Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor
• CPC Class Codes: F05D 2250/241 spherical
• CPC Class Codes: F05D 2250/62 smooth or fine
• CPC Class Codes: F05D 2250/621 polished
• CPC Class Codes: F05D 2260/20 Heat transfer, e.g. cooling
• CPC Class Codes: F05D 2260/98 Lubrication

Abstract

A method for smoothing surface roughness within an internal passageway is disclosed. In various embodiments, the method comprises developing a first sphere progression through a length of the internal passageway, each sphere within the first sphere progression having a first sphere diameter greater than or equal to a diameter of the internal passageway; and developing a second sphere progression through the length of the internal passageway, each sphere within the second sphere progression having a second sphere diameter greater than the first sphere diameter, whereby the inner surface of the internal passageway is smoothed, first by the first sphere progression and then by the second sphere progression.

Claims

1. A method for smoothing surface roughness within an internal passageway, comprising:

urging a first sphere into the internal passageway and to a first distance along 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; and

urging a second sphere into the internal passageway, the second sphere having a second sphere diameter greater than or equal to the diameter of the internal passageway, the second sphere urging the first sphere to a second distance along the length of the internal passageway,

wherein an inner surface of the internal passageway is smoothed by the first sphere along the second distance of the length and wherein the inner surface of the internal passageway is further smoothed by the second sphere along the first distance of the length.

2. The method of claim 1, further comprising urging a third sphere into the internal passageway, the third sphere urging the second sphere to the second distance along the length of the internal passageway and the first sphere to a third distance along the internal passageway.

3. The method of claim 2, further comprising urging subsequent spheres into the internal passageway until the first sphere exits the internal passageway.

4. The method of claim 1, wherein the second distance is measured from an inlet of the internal passageway.

5. The method of claim 1, wherein the second distance is measured from a starting point within the internal passageway.

6. The method of claim 1, wherein the diameter of the internal passageway is an average diameter.

7. The method of claim 1, wherein the first sphere diameter is equal to the diameter of the internal passageway.

8. The method of claim 1, wherein the second sphere diameter is equal to the first sphere diameter.

9. The method of claim 1, wherein the second sphere diameter is greater than the first sphere diameter.

10. The method of claim 1, wherein the internal passageway is substantially straight along the length.

11. The method of claim 1, wherein the internal passageway has a curved portion along the length.

12. The method of claim 11, wherein a set of spheres remaining in the internal passageway is urged to exit the internal passageway using at least one of a flexible rod and a source of pressurized air.

13. The method of claim 11, wherein a set of spheres remaining in the internal passageway is urged to exit the internal passageway using one or more subsequent spheres having a subsequent sphere diameter less than or equal to the first sphere diameter.

14. A method for smoothing surface roughness within an internal passageway, comprising:

urging a first sphere into the internal passageway and to a first distance along 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; and

urging a second sphere into 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 length of the internal passageway,

wherein an inner surface of the internal passageway is smoothed by the first sphere along the second distance of the length and wherein the inner surface of the internal passageway is further smoothed along a first portion of the length.

15. The method of claim 14, further comprising urging a third sphere into the internal passageway, the third sphere urging the second sphere to the second distance along the length of the internal passageway and the first sphere to a third distance along the internal passageway, wherein the third sphere has a third sphere diameter greater than the second sphere diameter.

16. The method of claim 15, further comprising urging subsequent spheres into the internal passageway until the first sphere exits the internal passageway.

17. The method of claim 16, wherein a set of spheres remaining in the internal passageway is urged to exit the internal passageway using at least one of a rod and a source of pressurized air.

18. A method for smoothing surface roughness within an internal passageway, comprising:

developing a first sphere progression through a length of the internal passageway, wherein each member within the first sphere progression has a first diameter greater than or equal to a diameter of the internal passageway, wherein an inner surface of the internal passageway is smoothed by the first sphere progression along the length; and

developing a second sphere progression through the length of the internal passageway, wherein each member within the second sphere progression has a second diameter greater than the first diameter, wherein the inner surface of the internal passageway is further smoothed by the second sphere progression along the length.

19. The method of claim 18, wherein the internal passageway includes a curved portion.

20. The method of claim 18, further comprising developing a final sphere progression, wherein each member within the final sphere progression has a final diameter less than a largest sphere diameter associated with any previous sphere progression developed within the internal passageway.