# US 2008/0178721 A1 · Production casing ripper

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2008/0178721 A1
- Document ID: US20080178721A1
- Status: Published application
- Kind: A1
- Application number: 11/669,087
- Filed: 2007-01-30
- Published: 2008-07-31
- Earliest claimed: 2007-01-30
- Assignees: Liquid Gold Well Service, Inc.
- Inventors: Shane Schwindt
- Web page: https://patentgrep.com/patent/US20080178721A1

## CPC

- B23D 21/14: cutting inside the tube
- B23D 11/00: Planing or slotting devices able to be attached to a machine tool, whether or not replacing an operative portion of the machine tool
- E21B 29/00: Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
- E21B 43/112: Perforators with extendable perforating members, e.g. actuated by fluid means
- Y10T 83/398: Internal tool is an active cutter
- B23D: PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR (making toothed gears or the like B23F; cutting metal by applying heat locally B23K; arrangements for copying or controlling B23Q)
- E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A production casing ripper comprising a swedge; spring housing; coupling; main housing; end piece; blade; and means for connecting the blade to the plunger; wherein the blade is situated inside of the main housing; wherein a plunger is situated inside of the main housing; wherein a primary spring is situated inside of the spring housing; wherein a primary pull rod is connected to the primary spring at one end and to the plunger at the other end; wherein when hydraulic pressure is introduced through the swedge, the plunger moves downward inside of the main housing and causes the blade to extend through an aperture in the main housing; and wherein when the hydraulic pressure is released, the primary spring causes the plunger to return to its original position, thereby causing the blade to retract.

## Claims

### Claim 1

A production casing ripper comprising:
(a) a swedge;
(b) a spring housing;
(c) a coupling;
(d) a main housing;
(e) an end piece;
(f) a blade; and
(g) means for connecting the blade to the plunger;
wherein the spring housing is a piece of tubing comprising two ends;
wherein one end of the spring housing is attached to the swedge and the other end of the spring housing is attached to the coupling;
wherein the main housing is a piece of tubing comprising two ends;
wherein one end of the main housing is attached to the coupling and the other end of the main housing is attached to the end piece;
wherein the inside diameter of the main housing is greater than the inside diameter of the spring housing;
wherein the blade is situated inside of the main housing;
wherein a plunger is situated inside of the main housing;
wherein a primary spring is situated inside of the spring housing;
wherein a primary pull rod comprising two ends is connected to the primary spring at one end and to the plunger at the other end;
wherein the main housing comprises an aperture;
wherein when hydraulic pressure is introduced through the swedge, the plunger moves downward inside of the main housing and causes the blade to extend through the aperture in the main housing; and
wherein when the hydraulic pressure is released, the primary spring causes the plunger to return to its original position, thereby causing the blade to retract.

### Claim 2 (depends on 1)

The production casing ripper of claim 1, wherein the outside diameter of the plunger is greater than the outside diameter of the primary spring.

### Claim 3 (depends on 1)

The production casing ripper of claim 1, wherein the spring housing comprises a top portion, a bottom portion, and an inside wall,
wherein the primary spring comprises a top end and a bottom end,
wherein the top end of the primary spring is movable,
wherein the inside wall of the spring housing is thicker on the bottom portion of the spring housing than on the top portion,
wherein the primary spring is situated inside of the top portion of the spring housing,
wherein the outside diameter of the primary spring is slightly less than the inside diameter of the top portion of the spring housing,
wherein the outside diameter of the primary spring is greater than the inside diameter of the bottom portion of the spring housing, and
wherein the thicker inside wall on the bottom portion of the spring housing creates a surface against which the bottom end of the primary spring is held stationary.

### Claim 4 (depends on 1)

The production casing ripper of claim 1, wherein the coupling comprises a bottom portion and a top portion,
wherein the inside diameter of the top portion of the coupling is less than the inside diameter of the bottom portion of the coupling, and
wherein the bottom portion of the coupling comprises a shoulder that limits the upward movement of the plunger inside the main housing.

### Claim 5 (depends on 1)

The production casing ripper of claim 1, wherein the blade comprises a cutting edge, wherein the cutting edge is sharp.

### Claim 6 (depends on 1)

The production casing ripper of claim 1, further comprising a first attachment arm and two second attachment arms,
wherein the first attachment arm comprises two ends,
wherein the plunger comprises a bottom end and a top end,
wherein the primary pull rod is attached to the top end of the plunger,
wherein one end of the first attachment arm is attached to the bottom end of the plunger and the other end of the first attachment arm is pivotally attached to the two second attachment arms,
wherein each of the second attachment arms comprises two ends,
wherein one end of each second attachment arm is pivotally attached to the first attachment arm and the other end of each second attachment arm is pivotally attached to the blade, and
wherein when the plunger moves downward inside the main housing, the second attachment arms pivot on the first attachment arm and on the blade, thereby causing the blade to extend outward through the aperture in the main housing.

### Claim 7 (depends on 1)

The production casing ripper of claim 1, wherein the blade is held in place by a pin that extends from one side of the main housing to the other.

### Claim 8 (depends on 7)

The production casing ripper of claim 7, wherein the main housing comprises two bushings that extend inward from the inside of the main housing,
wherein the pin passes through the two bushings, and
wherein the blade lies between the two bushings.

### Claim 9 (depends on 6)

The production casing ripper of claim 6, wherein the ripper is used to cut production casing inside of an oil, gas or water well,
wherein the first attachment arm can be rotated to make the first attachment arm shorter or longer, and
wherein said rotation of the first attachment arm alters the angle of the blade and the depth of cut in the production casing.

### Claim 10 (depends on 6)

The production casing ripper of claim 6, further comprising a secondary spring and a secondary pull rod,
wherein the secondary spring comprises two ends,
wherein one end of the secondary spring is attached to the blade and the other end of the secondary spring is attached to the secondary pull rod,
wherein the secondary pull rod is attached to the end piece,
wherein the main housing comprises a bottom end,
wherein the end piece is attached to the bottom end of the main housing,
wherein when the blade is extended through the aperture in the main housing, the secondary spring expands, thereby creating tension in the secondary spring, and
wherein when the hydraulic pressures is released, the tension in the secondary spring causes the blade to retract.

### Claim 11 (depends on 1)

The production casing ripper of claim 1, wherein the swedge comprises a weep hole,
wherein the plunger comprises one or more O rings,
wherein when the weep hole is plugged and hydraulic fluid is introduced through the swedge, the hydraulic fluid is fully contained within the swedge, the spring housing, and the main housing above the plunger, and
wherein when the weep hole is not plugged and hydraulic fluid is introduced through the swedge, the weep hole allows fluid pressure inside and outside of the ripper to be equalized.