RO127541A0 - Hydraulic cutter for cutting tubing and packers - Google Patents

Abstract

The invention relates to a hydraulic cutter for cutting tubing or a mechanical or hydraulic packer equipping an oil and/or gas extraction well, that cannot be extracted at the surface. According to the invention, the cutter comprises a supporting ring (7) and a recovering spring (6) for restoring a piston (4) to the initial position, between a launching reduction gear (2) and a piston (4) there being confined a circulation chamber (g), and inside a hollow body (1) there being confined an outletting chamber (a) which establishes the circulation communication between some communication orifices (b) provided in a pressing bushing (8) and the two external communication orifices (c) in the hollow body (1), to the lower side of the body (1) there existing a window (e) wherein there are located some cutting elements (10) which present at the upper side a profile (h) allowing the embedding and accommodating the pressing bushing (8) in a recess (d), fixed with an axle (9) to the body (1) an which are maintained closed by an elastic element (11).

Description

The invention relates to a hydraulic knife used for cutting tubing gaskets that cannot be extracted from the gas and oil wells and for cutting the body of mechanical or hydraulic packers that cannot be recovered ensuring controlled cutting.

It is known a cutting knife used for cutting tubing columns consisting of a tubular body, provided, at the top, with a reduction, and has a piston inside, provided with a recovery spring and a pressing bushing that presses on the extremity of three cutting elements, which are fixed, at a distance from the axis of the body, with a fixing bolt for each knife, to allow it to expand.

The hydraulic knife, according to the invention, ensures the cutting of tubing gaskets which cannot be extracted from the gas and oil wells by being formed of a tubular body which is screwed, at the top, in a launch reduction having an orifice. a piston, fitted with some sealing o-rings, is screwed into a pressing bush provided inside with a circulation hole communicating with two internal communication holes, and has, at the lower part, a locking housing for screwing with a safety ring. On the outside is mounted a support ring and a recovery spring for the return of the piston to the initial position, between the launch reduction and the piston is delimited a circulation chamber and inside the tubular body is delimited an opening chamber that realizes the communication for circulation between the holes communication, provided in the press sleeve and the two external communication ports located on the tubular body, at the lower part of the body there is a window where some cutting elements are presented which, at the top, a profile that allows for the insertion and concealment in a slot of the pressing bush, fixed with an axis of the tubular body and which are held closed by an elastic member.

By applying the invention, the following advantages are obtained: - cutting the tubing trapped in the oil and gas wells is done like a turning machine in a section of

^ “2 Ο 1 1 - Ο 1 4 2 4 - 2 1 -12- 2011

mechanical processing, removing: breakage, deformation, friction, breaking of the column in case of explosive cutting. The introduction of the knife is made with a flexible tubing installation that has, at the bottom, a hydraulic motor;

- due to the mounting of the cutting elements on the axis of the knife, small bodies were obtained;

- cutting the body of the packer that cannot be recovered from the oil and gas wells is done by inserting the knife with the tubing or rod gasket and recovering the packer in two subassemblies;

- operational safety;

- the cutting is performed in a short time;

- possibility of reuse by replacing used metal carbide.

The following is an example of an embodiment of the invention in connection with Figure 1, which represents a partial longitudinal section with a view of the cutting knife.

The hydraulic cutting knife, according to the invention, is formed by a tubular body 1 screwed, at the top, with a launch reduction 2 provided with an internal circulation hole f, and at the inside, with a piston 4, provided with o-rings. 5, and is screwed into the pressing sleeve 8 provided, inside, with a circulation hole f, which communicates with two internal circulation holes b, which is blocked for unscrewing by the safety ring 3, and is mounted on the outside, a retaining ring 7 and the recovery spring 6. between the launch gear 2 and the piston 4 there is a circulation chamber g. Inside the tubular body 1 is a delimitation chamber which communicates between the internal communication holes b and the two holes. of external communication c related to the tubular body 1. At the lower part of the tubular body 1 there is a window e where some cutting elements 10 are mounted, which present, at the upper part ara, a profile h that allows to hide in a slot d of the bushing 8 and at the bottom, are plated with a metal carbide film i and fixed on an axis 9 by the tubular body 1 and are held closed by an elastic element 11.

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1- tubular body

2- launch reduction

3- safety ring

4- piston

5- o-ring

6- recovery arc

7- support ring

8- press bushing

9- ax

10- cutting element

11- elastic element a-deburring chamber b-internal communication holes c-external communication holes d-slot e-window f-circulation hole g-circulation chamber h-profile i-metal carbide

Claims (1)

Hydraulic knife made of a tubular body (1) which is screwed, at the top, in a launch reduction (2) having a circulation hole (f) and a piston (4) is provided inside. with some sealing o-rings (5), which are screwed into a pressing bush (8) provided inside with a circulation hole (f) which communicates with two internal communication holes (b), and presents, at the lower part, a housing (d) locked for unscrewing with a safety ring (3) characterized in that it has mounted, on the outside, a support ring (7) and a recovery spring (6) for restoring the piston to its original position, between the launch reduction (2) and the piston (4) a circulation chamber (g) is delimited, and inside the tubular body (1) there is a delimitation chamber (a) which delimits the communication for circulation between the communication holes (b). ), provided in the press box has (8) and the two external communication ports (c) located on the tubular body (1), at the lower part of the body (1) there is a window (s) where some cutting elements (10) are fitted which present, at the upper part a profile (h) which allows the hinges (8) to be inserted and hidden in a slot (8), fixed with an axis (9) by the tubular body (1) and which are held closed by an elastic member ( 11).