METHODS FOR METAL COMPONENT REFURBISHMENT USING SUBTRACTIVE SURFACE

• US 20100233510A1
• Filed: 08/28/2008
• Published: 09/16/2010
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Remy Technologies LLC (BorgWarner Incorporated)
• Original Assignee: Remy Technologies LLC (BorgWarner Incorporated)
• Inventors: Michaud, Mark D., Winkelmann, Lane W., Sroka, Gary
• Granted Patent: US 9,180,568 B2
• Time in Patent Office: Days
• US Class Current: 428/687
• CPC Class Codes: B24B 31/00 Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor abrasive blasting machines B24C3/26
• CPC Class Codes: B24B 5/00 Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor B24B11/00 - B24B21/00 take precedence; honing machines or devices using abrading blocks performing axial and rotary movements superimposed on one another B24B33/00
• CPC Class Codes: Y10T 428/12993 Surface feature [e.g., rough, mirror]

Abstract

Refurbishing used or damaged engineering components is performed using a subtractive surface engineering process to remove material from worn or damaged critical surfaces. The method involves initially performing the process on the component to remove a first quantity of material from the surfaces, inspecting the surface of the component to determine the extent of damage and subsequently further performing the process to remove a further quantity of material if necessary.

Claims

1. A method of inspecting an engineering component for sub-surface damage, using a non-machining, media-based, subtractive surface engineering process to remove material from critically dimensioned surfaces of the component, the method comprising:

a) performing the process on the component to remove a quantity of material from the surfaces;

inspecting the surfaces of the component to determine an extent of apparent damage; and

on the basis of the inspection, determining whether;

i. the component is sufficiently refurbished for reuse;

or

ii. the component should be scrapped.

2. The method according to claim 1, comprising performing at least one further inspection cycle whereby for each further inspection cycle at least steps a), b) and c)i are repeated.

3. The method according to claim 1, wherein the inspection cycle is repeated until the extent of the apparent damage has stabilised.

4. The method according to claim 3, wherein the damage comprises micropitting, step b) comprises determining an extent of at least one micropit region and step c) comprises comparing the extent of the micropit region with an extent determined in a previous cycle.

5. The method according to claim 3, wherein the process is terminated when the extent of the micropit region is less than that determined in a previous cycle.

6. The method according to claim 1, wherein the process is terminated when the damage has been substantially removed.

7. The method according to claim 1, wherein during step a), a thickness of between 0.1 micron and 10 microns of material is removed.

8. The method according to claim 1, for inspecting a plurality of used components, whereby step a) is performed simultaneously for all components under the same process conditions.

9. The method according to claim 1, wherein the subtractive surface engineering process is a chemically accelerated vibratory processes.

10. The method according to claim 1, wherein the process to remove material from the surfaces is performed to achieve a surface finish Ra of less than 0.25 microns.

11. The method according to claim 1, performed without reference to the component'"'"'s engineering specification drawing or an equivalent specification sheet.

12. The method according to claim 1, wherein the process is performed without use of component specific tooling.

13. The method according to claim 1, further comprising providing an indicator on a surface to be treated and inspecting the indicator to determine a quantity of material removed.

14. A method for refurbishing an engineering component, using a non-machining, media-based, subtractive surface engineering process to remove material from worn or damaged critically dimensioned surfaces of the component, the method comprising:

a) initially performing the process on the component to remove a first quantity of material from the surfaces;

b) inspecting the surface of the component to determine an extent of damage; and

c) subsequently further performing the process to remove a further quantity of material.

15. The method according to claim 14, further comprising the repetition of steps b) and c).

16. The method according to claim 15, wherein steps b) and c) are repeated until the extent of the damage has stabilised.

17. The method according to claim 15, wherein the damage comprises micropitting and step b) determines an extent of at least certain micropit regions whereby during subsequent steps b) and c), the extent of the micropit regions is monitored and the process is terminated once the extent of the micropit regions has stabilised.

18. The method according to claim 14, wherein the process is terminated when the damage has been substantially removed.

19. The method according to claim 14, wherein during step a), a thickness of between 0.1 micron and 10 microns of material is removed.

20. The method according to claim 14, for refurbishing a plurality of used components, whereby after initially performing the process, those components are discarded where the extent of damage is greater than a predetermined amount.

21. The method according to claim 14, for simultaneously refurbishing a plurality of used components, whereby at least during step c), the components are all subjected to the same process conditions.

22. The method according to claim 14, wherein the subtractive surface engineering process is a chemically accelerated vibratory process.

23. The method according to claim 14, wherein the process is performed to achieve a surface finish Ra of less than 0.25 microns over the surfaces.

24. The method according to claim 14, performed without reference to the component'"'"'s engineering specification drawing or an equivalent specification sheet.

25. The method according to claim 14, wherein the process is performed without use of component specific tooling.

26. The method according to claim 14, further comprising providing an indicator on a surface to be treated and inspecting the indicator to determine a quantity of material removed.

27. (canceled)

28. (canceled)

29. An engineering component comprising a critically-dimensioned metal to metal contact surface, the surface being refurbished using a non-machining, media-based, subtractive surface engineering process, wherein the surface comprises residual surface damage and a surface roughness Ra of less than 0.25 microns.

30. The component of claim 29, wherein the component is selected from the group comprising gears, shafts, bearings, pistons, axles, cams, seats, and seals.