Weld Overlay Structure and a Method of Providing a Weld Overlay Structure

• US 20120214017A1
• Filed: 02/22/2011
• Published: 08/23/2012
• Est. Priority Date: 02/22/2011
• Status: Abandoned Application

• Current Assignee: Amec Foster Wheeler North America Corp. (John Wood Group PLC), Pourin Welding Engineering Company Limited
• Original Assignee: Foster Wheeler North America Corporation (John Wood Group PLC), Pourin Welding Engineering Company Limited
• Inventors: MURPHY, John, LEE, Haisheng
• Application Number:
  US13/032,002
• Publication Number:
  US 20120214017A1
• Time in Patent Office: Days
• US Class Current: 428/592
• CPC Class Codes: B23K 2101/14 Heat exchangers
• CPC Class Codes: B23K 9/048 on cylindrical surfaces
• CPC Class Codes: F22B 37/025 Devices and methods for diminishing corrosion, e.g. by preventing cooling beneath the dew point
• CPC Class Codes: F22B 37/108 Protection of water tube walls
• CPC Class Codes: Y10T 428/12333 Helical or with helical component
• CPC Class Codes: Y10T 428/12451 Macroscopically anomalous interface between layers

Abstract

A method of providing a weld overlay structure on a heat transfer tube or a membrane surface. A first continuous bead portion of an overlay material is applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material. A second continuous bead portion of the overlay material is applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material, in which the second bead portion partially overlaps with the first bead portion, forming a groove between the first bead portion and the second bead portion. A third continuous bead portion of an overlay material is applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material into the groove between the first bead portion and the second bead portion, so as to form a relatively smooth surface.

Claims

1. A method of providing a weld overlay structure on a heat transfer tube or a membrane surface, the method comprising the steps of:

applying a first continuous bead portion of an overlay material onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material;

applying a second continuous bead portion of the overlay material onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material, wherein the second bead portion partially overlaps with the first bead portion, forming a groove between the first bead portion and the second bead portion; and

applying a third continuous bead portion of an overlay material onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material into the groove between the first bead portion and the second bead portion, so as to form a relatively smooth surface.

2. The method according to claim 1, wherein the average overlap between the first bead portion and the second bead portion is less than 20%.

3. The method according to claim 2, wherein the average overlap between the first bead portion and the second bead portion is less than 15%.

4. The method according to claim 1, wherein the average overlap between the first bead portion and the second bead portion is less than 5 mm.

5. The method according to claim 4, wherein the average overlap between the first bead portion and the second bead portion is less than 3 mm.

6. The method according to claim 1, wherein the overlay material of the third continuous bead portion is the same as that of the first continuous bead portion and the second continuous bead portion.

7. The method according to claim 1, wherein the first continuous bead portion and the second continuous bead portion are applied by using a common weld head.

8. The method according to claim 7, wherein the first continuous bead portion, the second continuous bead portion, and the third continuous bead portion are applied by using a common weld head.

9. The method according to claim 1, wherein the first continuous bead portion and the second continuous bead portion are applied by using first welding parameters, and the third continuous bead portion is applied by using second welding parameters, which are different from the first welding parameters.

10. The method according to claim 1, wherein the first continuous bead portion and the second continuous bead portion form a spiral tube overlay, and the third continuous bead forms another spiral tube overlay.

11. The method according to claim 1, wherein the first continuous bead portion, the second continuous bead portion and the third continuous bead portion form parallel straight beads.

12. A weld overlay structure on a heat transfer tube or a membrane surface, the weld overlay structure comprising:

a first continuous bead portion of an overlay material applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material;

a second continuous bead portion of the overlay material applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material, wherein the second bead portion partially overlaps with the first bead portion, forming a groove between the first bead portion and the second bead portion; and

a third continuous bead portion of an overlay material applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material into the groove between the first bead portion and the second bead portion, so as to form a relatively smooth surface.

13. The weld overlay structure according to claim 12, wherein the average overlap between the first bead portion and the second bead portion is less than 20%.

14. The weld overlay structure according to claim 13, wherein the average overlap between the first bead portion and the second bead portion is less than 15%.

15. The weld overlay structure according to claim 12, wherein the average overlap between the first bead portion and the second bead portion is less than 5 mm.

16. The weld overlay structure according to claim 15, wherein the average overlap between the first bead portion and the second bead portion is less than 3 mm.

17. The weld overlay structure according to claim 12, wherein the overlay material of the third continuous bead portion is the same as that of the first and second continuous bead portions.

18. The weld overlay structure according to claim 12, wherein the first continuous bead portion and the second continuous bead portion form a spiral tube overlay, and the third continuous bead portion forms another spiral tube overlay.

19. The weld overlay structure according to claim 12, wherein the first continuous bead portion, the second continuous bead portion and the third continuous bead portion form parallel straight beads.