Cylinder liner assembly having a thermal barrier coating

Patent metadata

Field	Value
Publication number	US-9657682-B2
Application number	US-201514728035-A
Country	US
Kind code	B2
Filing date	Jun 2, 2015
Priority date	Jun 2, 2015
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A cylinder liner assembly is disclosed for use with an engine. The cylinder liner assembly may include a liner having a hollow generally cylindrical body extending from a top end to a bottom end along a longitudinal axis, and an internal annular cuff ring groove formed at the top end of the liner. An internal surface of the internal cuff ring groove may include a metal spray coating having a thermal conductivity that is less than a thermal conductivity of a base material of the liner to act as a thermal insulating layer. A cuff ring may be disposed within the internal cuff ring groove at the top end of the liner in contact with the metal spray coating. A seal may be disposed around an outer circumferential surface of the liner approximately in axial alignment with an internal axial end of the internal cuff ring groove.

First claim

What is claimed is:

1. A cylinder liner assembly, comprising: a liner having a hollow generally cylindrical body extending from a top end to a bottom end along a longitudinal axis, and an internal annular cuff ring groove formed at the top end of the liner; an internal surface of the cuff ring groove including a metal spray coating having a thermal conductivity that is less than a thermal conductivity of a base material of the liner to act as a thermal insulating layer, the metal spray coating being applied on an inner circumferential surface of the cuff ring groove and a portion of an axial shoulder at an internal axial end of the cuff ring groove; a cuff ring disposed within the cuff ring groove at the top end of the liner in contact with the metal spray coating; and a seal for a water jacket disposed around an outer circumferential surface of the liner approximately in axial alignment with an internal axial end of the cuff ring groove.

2. The cylinder liner assembly of claim 1 , wherein the metal spray coating is applied on an internal circumferential surface of the internal annular cuff ring groove.

3. The cylinder liner assembly of claim 1 , wherein the metal spray coating has a thermal conductivity that is at least 10% less than the thermal conductivity of the base material of the liner.

4. The cylinder liner assembly of claim 1 , wherein the metal spray coating has a thermal conductivity that is between approximately 10% and 90% of the thermal conductivity of the base material of the liner.

5. The cylinder liner assembly of claim 1 , wherein the metal spray coating is made from a material selected from a group consisting of iron-chromium-aluminum alloys, aluminum alloys, aluminum alloys with high silicon content, aluminum-bronze alloys, stainless steel alloys, nickel alloys, nickel-aluminum alloys, and carbon steel alloys.

6. The cylinder liner assembly of claim 1 , wherein the metal spray coating is applied using a process selected from a group of processes consisting of low and high pressure cold spray processes, plasma spraying (air (APS), vacuum (VPS) and low pressure (LPPS)), high velocity air-fuel thermal spray processes, high velocity oxy-fuel (HVOF) thermal spray processes, physical vapor deposition processes, solution plasma spray processes, suspension plasma processes, flame spray processes, and electric arc spray processes.

7. The cylinder liner assembly of claim 6 , wherein the metal spray coating is made from a material selected from a group consisting of nickel alloys, nickel-aluminum alloys, iron-chromium-aluminum alloys, aluminum alloys, aluminum alloys with high silicon content, aluminum-bronze alloys, stainless steel alloys, and carbon steel alloys.

8. The cylinder liner assembly of claim 7 , wherein feedstock material for the metal spray coating is provided as a powder.

9. A method of producing a cylinder liner configured to be installed into a cylinder of an engine, the method comprising: forming the cylinder liner with a hollow cylindrical body extending along a longitudinal axis, and an annular flange protruding radially outward at a top axial end of the cylindrical body; forming an internal annular recess at the top end of the cylindrical body, the annular recess being configured to extend axially into the top end of the cylindrical body from a top surface of the flange to an internal axial shoulder, and configured to receive a cuff ring within the annular recess; a seal for a water jacket disposed around an outer circumferential surface of the liner approximately in axial alignment with the internal axial shoulder of the internal annular recess; applying a coating over the internal annular recess by a metal spray process, the metal spray coating being applied on at least one of an inner circumferential surface of the internal annular recess and a portion of the internal axial shoulder; and installing a cuff ring into the internal annular recess.

10. The method of claim 9 , further including applying a coating over the internal annular recess using a process selected from a group of processes consisting of low and high pressure cold spray processes, plasma spraying (air (APS), vacuum (VPS) and low pressure (LPPS)), high velocity air-fuel thermal spray processes, high velocity oxy-fuel (HVOF) thermal spray processes, physical vapor deposition processes, solution plasma spray processes, suspension plasma processes, flame spray processes, and electric arc spray processes.

11. The method of claim 10 , wherein the metal spray coating is made from a material selected from a group consisting of iron-chromium-aluminum alloys, aluminum alloys, aluminum alloys with high silicon content, aluminum-bronze alloys, stainless steel alloys, nickel alloys, nickel-aluminum alloys, and carbon steel alloys.

12. The method of claim 11 , wherein feedstock material for the metal spray coating is provided as one of a wire or a powder.

13. A method of applying a thermal barrier to a cylinder liner, wherein the cylinder liner comprises a hollow cylindrical body extending from a top end to a bottom end along a longitudinal axis, an internal annular recess formed at the top end, and a flange connected to the hollow cylindrical body at the top end for engagement with a cylinder block of an engine, the method comprising: applying a metal spray coating on at least one of an internal circumferential surface of the internal annular recess and a portion of an axial shoulder at an internal axial end of the internal annular recess, a seal for a water jacket disposed around an outer circumferential surface of the liner approximately in axial alignment with the axial shoulder at the internal axial end of the internal annular recess; the metal spray coating using a process selected from a group of spray processes consisting of low and high pressure cold spray processes, plasma spraying (air (APS), vacuum (VPS) and low pressure (LPPS)), high velocity air-fuel thermal spray processes, high velocity oxy-fuel (HVOF) thermal spray processes, physical vapor deposition processes, solution plasma spray processes, suspension plasma processes, flame spray processes, and electric arc spray processes.

14. The method of claim 13 , wherein the metal spray coating is applied in order to result in a thermal conductivity of the coating that is between approximately 10% and 90% of the thermal conductivity of the liner material.

15. The method of claim 13 , wherein the metal spray coating is applied using a spray process including controlling at least one of a standoff distance between a spray nozzle and the internal annular recess, an air pressure used to propel molten coating material from the spray nozzle, an amount of electric current used to melt wire or powder feedstock for the coating material, an angle between a direction of spray and a surface of the internal annular recess, a temperature, a humidity, and a transverse speed at which the spray nozzle is moved relative to the surface of the internal annular recess during application of the coating.

Assignees

• Caterpillar Inc

Inventors

• Graham Curtis John
• Cavanaugh Daniel Thomas
• YOUNG Taylor Douglas

Classifications

• C23C4/129

  Flame spraying · CPC title

• C23C24/04

  Impact or kinetic deposition of particles · CPC title

• F02F2001/006

  having a ring at the inside of a liner or cylinder for preventing the deposit of carbon oil particles, e.g. oil scrapers · CPC title

• F02F11/005

  involving cylinder liners · CPC title

• F02F2001/008

  Stress problems, especially related to thermal stress · CPC title