Method of remanufacturing used cylinder liners and mask and used cylinder liner assembly

Patent metadata

Field	Value
Publication number	US-9676068-B2
Application number	US-201313940611-A
Country	US
Kind code	B2
Filing date	Jul 12, 2013
Priority date	Jul 12, 2013
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

Remanufacturing a used cylinder liner includes receiving a used cylinder liner having a fillet relieved of residual compressive stress via service in an engine, and compressing a material substrate of the cylinder liner forming a fatigue sensitive fillet, such that a non-uniform profile of the fillet is reshaped via plastic deformation of the material substrate. Residual compressive stress is restored to the fillet at least in part via the plastic deformation. A mask and used cylinder liner assembly for processing the used cylinder liner during remanufacturing is also disclosed.

First claim

What is claimed is:

1. A method of remanufacturing a cylinder liner for an internal combustion engine comprising the steps of:
receiving a used cylinder liner having a fillet relieved of residual compressive stress via service in an internal combustion engine and having a non-uniform profile, the fillet extending circumferentially around a center axis of the cylinder liner at a fatigue sensitive location and adjoining a radially projecting cylinder liner flange, and a roll burnishing groove being formed within the fillet;
compressing a material substrate of the cylinder liner forming the fillet, such that the non-uniform profile of the fillet is reshaped via plastic deformation of the material substrate; and
restoring residual compressive stress to the fillet at least in part via the plastic deformation;
wherein the compressing of the material substrate includes compressing the material substrate in a manner that deepens the profile of the fillet and reduces a depth of the roll burnishing groove.

2. The method of claim 1 wherein the step of receiving includes receiving the used cylinder liner where the non-uniform profile includes a circumferentially non-uniform profile of rotation about the center axis.

3. The method of claim 2 wherein the profile of rotation is non-uniform in surface contour within the roll burnishing groove such that the fillet is unsuited to re-rolling, and further comprising a step of reducing non-uniformity in the profile of rotation via the plastic deformation.

4. The method of claim 2 wherein the used cylinder liner is formed throughout by the material substrate, and the radially projecting flange includes a radially projecting end flange having an axially inward engine block face for top support of the used cylinder liner in service.

5. The method of claim 4 wherein the step of compressing further includes applying compressive force to the material substrate uniformly about the center axis, and in a force direction oblique to the center axis.

6. The method of claim 5 wherein the step of compressing further includes compressing the material substrate such that the profile of rotation is deepened in the force direction.

7. The method of claim 5 wherein the step of compressing further includes compressing the material substrate via peening the fillet.

8. The method of claim 7 wherein peening the fillet includes shot peening the fillet such that the force direction as defined by a spray cone of the shot is oriented at about 45° to the center axis and at about 45° to the engine block face.

9. The method of claim 8 wherein shot peening the fillet further includes shot peening a filler band groove formed in part by the fillet and in part by a radially projecting skirt axially spaced from the radially projecting flange.

10. A method of processing internal combustion engine cylinder liners comprising the steps of:
receiving a group of used cylinder liners each having a fatigue sensitive fillet relieved of residual compressive stress via service in an internal combustion engine and having a roll burnishing groove within the fillet;
sorting the group of used cylinder liners into a first subset for remanufacturing, responsive to satisfaction of a fillet restorability criterion, and into a second subset;
compressing material substrates forming the fillets in each of the cylinder liners of the first subset such that the fillets are reshaped via plastic deformation of the corresponding material substrate to restore residual compressive stress therein;
wherein compressing material substrates further includes deepening a profile of the fillets in each of the cylinder liners by way of peening the fillets; and
forwarding the used cylinder liners following restoration of the residual compressive stress to an inventory for returning to service in an internal combustion engine.

11. The method of claim 10 wherein the fillets in the used cylinder liners of the first subset each have a unique profile when received.

12. The method of claim 11 wherein the step of sorting further includes sorting used cylinder liners having fillets free from cracks into the first subset, and sorting used cylinder liners having cracked fillets into the second subset.

13. The method of claim 11 wherein the step of compressing further includes compressing the material substrates in a filler band groove formed in part by the fillet in each of the used cylinder liners of the first subset.

14. The method of claim 13 wherein the peening further includes shot peening the filler band groove in each of the used cylinder liners of the first subset.

15. The method of claim 10 further comprising a step of packaging each of the used cylinder liners of the first subset with pistons and seals in a plurality of cylinder packs.

16. The method of claim 15 further comprising a step of populating the inventory with cylinder packs formed from the used cylinder liners, and with cylinder packs formed from new cylinder liners and interchangeable with the cylinder packs formed from the used cylinder liners.

Assignees

• Caterpillar Inc
• Caterpillar Inc

Inventors

• Claver Aaron
• Simpson Trent

Classifications

• F02F2001/008

  Stress problems, especially related to thermal stress · CPC title

• Y10T29/49233

  Repairing, converting, servicing or salvaging · CPC title

• F16J10/04

  Running faces; Liners · CPC title

• C21D7/06

  by shot-peening or the like · CPC title

• F02F1/004

  Cylinder liners (F02F1/08, F02F1/16 take precedence) · CPC title