FLUID CONDUITS WITH INTEGRAL END FITTINGS AND ASSOCIATED METHODS OF MANUFACTURE AND USE

• US 20090173130A1
• Filed: 06/11/2008
• Published: 07/09/2009
• Est. Priority Date: 01/04/2008
• Status: Active Grant

• Current Assignee: Cerro Flow Products LLC (Berkshire Hathaway Incorporated)
• Original Assignee: Cerro Flow Products LLC (Berkshire Hathaway Incorporated)
• Inventors: Blair, Steven L. SR., Nixon, Forrest, Duggan, Michael
• Granted Patent: US 7,987,690 B2
• Time in Patent Office: Days
• US Class Current: 72/342.100
• CPC Class Codes: B21J 5/08 Upsetting
• CPC Class Codes: F16L 13/142 with a sealing element inserted into the female part before crimping or rolling
• CPC Class Codes: F16L 21/03 placed in the socket before connection F16L21/022, F16L21/025 take precedence
• CPC Class Codes: F16L 21/035 placed around the spigot end before connection F16L21/022, F16L21/025 take precedence

Abstract

Fluid conduits for plumbing and other uses having integral end fittings are disclosed herein. A method of forming a fluid conduit in accordance with an embodiment of the disclosure includes providing a copper tube having a first inner diameter and a first wall thickness, and heat treating an end portion of the copper tube to a predetermined hardness. The method can further include increasing the wall thickness of the end portion from the first wall thickness to a second wall thickness, and increasing the inner diameter of the end portion from the first inner diameter to a second inner diameter. The method further includes forming a circular groove in an interior surface of the end portion and positioning a seal in the circular groove.

Claims

1. A method of forming a fluid conduit, the method comprising:

providing a copper tube having a first inner diameter and a first wall thickness;

heat treating an end portion of the copper tube;

increasing the wall thickness of the end portion from the first wall thickness to a second wall thickness;

increasing the inner diameter of the end portion from the first inner diameter to a second inner diameter; and

forming a circular groove in an interior surface of the end portion.

2. The method of claim 1 wherein heat treating the end portion of the copper tube includes reducing the hardness of the end portion from a first hardness to a second predetermined hardness that is less than the first hardness.

3. The method of claim 1 wherein heat treating the end portion of the copper tube includes annealing the end portion to reduce the hardness.

5. The method of claim 1, further comprising cooling the end portion after heat treating the end portion and before increasing the wall thickness and the inner diameter of the end portion.

6. The method of claim 5 wherein cooling the end portion includes quenching the end portion.

7. The method of claim 1 wherein at least one of increasing the wall thickness of the end portion and increasing the inner diameter of the end portion includes upset forging the end portion of the copper tube.

8. The method of claim 1 wherein at least one of increasing the wall thickness of the end portion and increasing the inner diameter of the end portion includes hot forging the end portion of the copper tube.

9. The method of claim 1, further comprising positioning a seal in the circular groove in the end portion of the copper tube.

4. The method of claim I wherein heat treating the end portion includes annealing the end portion to a hardness in the range of approximately 30-40 in a Rockwell Hardness 15T scale.

10. A method of manufacturing a plumbing conduit, the method comprising:

providing a copper tube having a generally uniform cross-section with an outer diameter and a wall thickness;

annealing an end portion of the copper tube;

upset forging the end portion to provide an inner diameter of the end portion that is equal to or greater than the outer diameter of the copper tube;

forming a circumferential groove in an interior surface of the end portion; and

disposing a resilient seal in the circumferential groove.

11. The method of claim 10, further comprising quenching the end portion of the copper tube after annealing the end portion.

12. The method of claim 10 wherein upset forging the end portion of the copper tube includes positioning the end portion in a first die and inserting a second die into the end portion.

13. The method of claim 10 wherein annealing the end portion of the copper tube includes induction annealing the end portion.

14. The method of claim 10 wherein annealing the end portion of the copper tube includes annealing the end portion to have a hardness of approximately 30-40 in the Rockwell Hardness 15T scale.

15. The method of claim 10 wherein the wall thickness of the copper tube is a first wall thickness, and wherein upset forging the end portion of the copper tube includes increasing the wall thickness of the end portion from the first wall thickness to a second wall thickness.

16. A method of manufacturing a plumbing conduit, the method comprising:

providing a copper tube having a generally uniform cross-section with an outer diameter and a first wall thickness;

heat treating an end portion of the copper tube to a predetermined hardness;

while the end portion of the copper tube is at an elevated temperature from the heat treating, upsetting the heated end portion to provide the end portion with a second wall thickness that is greater than the first wall thickness;

forming a circular groove in an interior surface of the end portion; and

positioning a seal in the circular groove.

17. The method of claim 16 wherein upsetting the heated end portion of the copper tube includes hot forging the end portion.

18. The method of claim 16 wherein upsetting the heated end portion of the copper tube includes increasing an inner diameter of the end portion to be equal to or greater than the outer diameter of the copper tube.

19. The method of claim 16 wherein heat treating the end portion of the copper tube to a predetermined hardness includes annealing the end portion to have a hardness of approximately 30-40 in the Rockwell Hardness 15T scale.