Patent ID: 7581591
Filing Date: 2009-09-01
Classification: B23D,E21B,Y10T

Abstract:
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; (g) means for connecting the blade to the plunger; (h) a secondary spring and a secondary pull rod; and (i) a first attachment arm and two second attachment arms; 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; 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; 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, 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; 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.