Isolation valve with a dead chamber

1. An isolation valve with a dead chamber for piping conveying hydrocarbons, the isolation valve comprising:

a body with a fluid-passing conduit, and

an obturation device for obturating the fluid passage in the conduit, the obturation device including a rotating body which is actuated between a fluid-passing position and a position for obturating the fluid passage in the conduit, the rotating body forming a dead chamber in the position for obturating the fluid passage in the conduit, a wall of the obturation device comprising a through-hole, the rotating body comprising a tapered rotating plug,

wherein the rotating body also comprises two sliders translationally mounted on the tapered rotating plug in the body so that a translation of the tapered rotating plug along an axis thereof induces translation of both sliders along a direction substantially perpendicular to the axis of the tapered rotating plug,

wherein the through-hole extends through one of the sliders and the tapered rotating plug so as to form a continuous hole in the position for obturating the fluid passage in the conduit,

wherein the obturation device includes a decompression device that is positioned in the slider with the through-hole.

2. The isolation valve with a dead chamber according to claim 1 , wherein the decompression device is formed by a calibrated valve.

3. The isolation valve with a dead chamber according to claim 2 , wherein the calibrated valve is screwed, pinned or forcibly inserted into the slider of the obturation device with the through-hole.

4. The isolation valve with a dead chamber according to claim 1 , wherein the through-hole is made between the dead chamber and the fluid-passing conduit.

5. The isolation valve with a dead chamber according to claim 4 , wherein the through-hole is made in the wall of the obturation device intended to be positioned towards the upstream side of the isolation valve, in a position for obturating the fluid passage in the conduit.

6. The isolation valve with a dead chamber according to claim 1 , wherein the tapered plug has a shaft for guiding the rotation of the rotating body.

7. A piping for conveying hydrocarbons comprising at least two pipes connected through an isolation valve with a dead chamber, the isolation valve comprising:

a body with a fluid-passing conduit,

an obturation device for obturating the fluid passage in the conduit, the obturation device including a rotating body which is actuated between a fluid-passing position and a position for obturating the fluid passage in the conduit, the rotating body forming a dead chamber in the position for obturating the fluid passage in the conduit, a wall of the obturation device comprising a through-hole, the rotating body comprising a tapered rotating plug,

wherein the rotating body also comprises two sliders translationally mounted on the tapered rotating plug in the body so that a translation of the tapered rotating plug along an axis thereof induces translation of both sliders along a direction substantially perpendicular to the axis of the tapered rotating plug,

wherein the through-hole extends through one of the sliders and the tapered rotating plug so as to form a continuous hole in the position for obturating the fluid passage in the conduit,

wherein the obturation device includes a decompression device that is positioned in the slider with the through-hole.

8. The piping for conveying hydrocarbons according to claim 7 , wherein the decompression device is formed by a calibrated valve.

9. The piping for conveying hydrocarbons according to claim 8 , wherein the calibrated valve is screwed, pinned or forcibly inserted into the slider of the obturation device with the through-hole.

10. The piping for conveying hydrocarbons according to claim 7 , wherein the through-hole is made between the dead chamber and the fluid-passing conduit.

11. The piping for conveying hydrocarbons according to claim 10 , wherein the through-hole is made in the wall of the obturation device intended to be positioned towards the upstream side of the isolation valve, in a position for obturating the fluid passage in the conduit.

12. The piping for conveying hydrocarbons according to claim 7 , wherein the tapered plug has a shaft for guiding the rotation of the rotating body.

13. An isolation valve with a dead chamber for piping conveying hydrocarbons, the isolation valve comprising:

a body with a fluid-passing conduit;

an obturation device for controlling fluid flow through the fluid-passing conduit, the obturation device including a rotating body that is moveable between an open position and a closed position, the rotating body including a tapered rotating plug that forms a dead chamber in the obturation device when the rotating body is in the closed position, the tapered rotating plug having a wall with a through-hole disposed in fluid communication with the dead chamber; the rotating body including two sliders translationally mounted on the tapered rotating plug so that translation of the tapered rotating plug along an axis of the tapered rotating plug induces translation of the two sliders along a direction substantially perpendicular to the axis of the tapered rotating plug the through-hole extending through one of the sliders; and

a decompression device positioned in the slider with the through-hole,

wherein translation of the tapered rotating plug along the axis of the tapered rotating plug brings the through-hole in the wall of the tapered rotating plug into alignment with the decompression device when the tapered rotating plug is in the closed position so as to form a continuous hole that extends through the wall of the tapered rotating plug and the slider with the decompression device.

14. The isolation valve with a dead chamber according to claim 13 , wherein the decompression device is a calibrated valve.

15. The isolation valve with a dead chamber according to claim 13 , wherein the decompression device is screwed, pinned or forcibly inserted into one of the sliders.