Hydraulic plugs

Patent metadata

Field	Value
Publication number	US-10837587-B2
Application number	US-201816173394-A
Country	US
Kind code	B2
Filing date	Oct 29, 2018
Priority date	Oct 28, 2017
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

A plug for sealing a passage extending about a longitudinal axis (A) comprises a shell having a circumferential wall extending between an end wall and an opening, and an internal cavity extending axially within the shell, and an expander having a head and a shank extending axially from the head, the head retained with the cavity and the shank extending axially through the opening of the cavity, wherein the circumferential wall comprises an inner surface having at least a first region and a second region, the second region proximate the opening and the first region adjacent to the second region and extending therefrom towards the end wall, the inner surface in the first region tapering inwardly relative to the longitudinal axis (A) to provide a first angled ramp, and the inner surface in the second region tapering further inwardly to provide a second angled ramp.

First claim

The invention claimed is:

1. A plug for sealing a passage extending about a longitudinal axis (A), the plug comprising:
a shell having a circumferential wall extending between an end wall and an opening, and an internal cavity extending axially within the shell; and
an expander having a head and a shank extending axially from the head, the head retained with the cavity and the shank extending axially through the opening of the cavity, wherein the circumferential wall comprises an inner surface having at least a first region and a second region, the second region proximate the opening and the first region adjacent to the second region and extending therefrom towards the end wall, the inner surface in the first region tapering inwardly relative to the longitudinal axis (A) to provide a first angled ramp, and the inner surface in the second region tapering further inwardly relative to the longitudinal axis (A) at an angle θ that is greater than an angle α at which the inner surface in the first region extends relative to the longitudinal axis (A) to provide a second angled ramp, the expander being operable to urge the circumferential wall of the shell outwardly as it moves along the inner surface in the first region.

2. The plug as recited in claim 1 , wherein the inner surface defines a third region adjacent to the first region, the inner surface in the third region extending relative to the longitudinal axis (A) at an angle less than the taper angle of the first angled ramp.

3. The plug as recited in claim 2 , wherein the inner surface in the third region extends substantially parallel to the longitudinal axis (A).

4. The plug as recited in claim 2 , wherein the inner surface in the third region extends to the end wall of the shell.

5. The plug as recited in claim 1 , wherein the first angled ramp is tapered inwardly relative to the longitudinal axis (A) at an angle (α) between 1 and 7 degrees.

6. The plug as recited in claim 1 , wherein the shank comprises a weakened region proximate the head.

7. The plug as recited in claim 1 , wherein the head is formed of a harder material than the shell.

8. The plug as recited in claim 1 , wherein the shell or the expander comprises stainless steel, an aluminium alloy, a copper alloy, a titanium alloy or a plastic.

9. A plug for sealing a passage extending about a longitudinal axis (A), the plug comprising:
a shell having a circumferential wall extending between an end wall and an opening, and an internal cavity extending axially within the shell;
an expander having a head and a shank extending axially from the head, the head retained with the cavity and the shank extending axially through the opening of the cavity, wherein the circumferential wall comprises an inner surface having at least a first region and a second region, the second region proximate the opening and the first region adjacent to the second region and extending therefrom towards the end wall, the inner surface in the first region tapering inwardly relative to the longitudinal axis (A) to provide a first angled ramp, and the inner surface in the second region tapering further inwardly to provide a second angled ramp, the expander being operable to urge the circumferential wall of the shell outwardly as it moves along the inner surface in the first region; and
a tool having a central part and an outer part, the central part configured to apply a tensile force (T) to the shank and the outer part configured to maintain the axial position of the shell.

10. The plug as recited claim 1 , wherein the circumferential wall comprises a substantially cylindrical outer surface having a diameter (D 2 ) substantially corresponding to an inner diameter (D 1 ) of the passage.

11. The plug as recited in claim 1 , wherein the head is a sphere or part of a sphere.

12. The plug as recited in claim 11 , wherein an inner diameter (D 4 ) of the circumferential wall proximate the end wall of the shell substantially corresponds to an outer diameter (D 3 ) of the head of the expander.

13. A method of sealing a passage with the hydraulic plug of claim 1 , comprising:
inserting the hydraulic plug into the passage; and
applying a tensile force (T) to the shank to pull the head in an axial direction towards the opening, wherein the axial movement of the head is partially inhibited by the first angled ramp such that the circumferential wall is urged against an inner wall as the head moves along the axial direction to gradually increase an interference fit pressure between the shell and the inner wall of the passage, and the axial movement of the head is substantially completely inhibited by the second angled ramp such that the shank breaks away from the head once the tensile force (T) reaches a breaking load of the expander.

14. The method of claim 13 , wherein the axial movement of the head is not inhibited by the inner surface of the circumferential wall in a third region adjacent to the first region.

15. The method of claim 14 , wherein the head of the expander remains in the shell to seal the plug within the passage.

16. The plug as recited in claim 1 , wherein the angle (a) is between 2 and 6 degrees.

17. The plug as recited in claim 1 , wherein the angle (a) is between 3 and 5 degrees.

Assignees

• Hamilton Sundstrand Corp
• Hamilton Sunstrand Corp

Inventors

• Cis Marcin
• Kiełbowicz Dariusz

Classifications

• F16L55/13 Primary

  the closure device being a plug fixed by plastic deformation · CPC title