Vented optical tube

Patent metadata

Field	Value
Publication number	US-2017038545-A1
Application number	US-201615169131-A
Country	US
Kind code	A1
Filing date	May 31, 2016
Priority date	Aug 7, 2015
Publication date	Feb 9, 2017
Grant date	—

Abstract

Vented optical tube. At least some illustrative embodiments are conduits comprising a tube having a wall defining an interior volume of the tube. One or more optical fibers are disposed within the interior volume. The wall includes a plurality of vents passing from an outer surface of the wall to the interior volume, the plurality of vents disposed along a length of the tube, and wherein the vents are configured to convey a fluid in contact with the outer surface into the interior volume of the tube.

First claim

What is claimed is:

1 . An apparatus comprising:
a conduit including:
a tube having a wall defining an interior volume of the tube;
one or more optical fibers disposed within the interior volume of the tube; wherein:
the wall includes a plurality of vents passing from an outer surface of the wall to the interior volume, the plurality of vents disposed along a length of the tube; and
wherein the vents are configured to convey a fluid in contact with the outer surface into the interior volume of the tube.

2 . The apparatus of claim 1 wherein the tube includes an end configured to convey fluid into the interior volume of the tube.

3 . The apparatus of claim 1 wherein the tube comprises a plastic selected from the group consisting of:
polypropylene; and
polyvinylidene fluoride (PVDF).

4 . The apparatus of claim 1 wherein the tube comprises a metal.

5 . The apparatus of claim 4 wherein the metal comprises stainless steel.

6 . The apparatus of claim 1 wherein the tube is helicoidally disposed about a central axis of a sensor cable.

7 . The apparatus of claim 1 wherein a size of the vents is configured to provide a volumetric flow rate into the interior volume of greater than or equal to about 1000 cubic millimeters/sec.

8 . The apparatus of claim 1 wherein the one or more optical fibers comprise a buffer layer disposed on an outer surface of a primary polymer coating of the optical fiber.

9 . The apparatus of claim 1 wherein the vents have a diameter equal to or greater than about 20 micrometers.

10 . The apparatus of claim 9 wherein the diameter of the vents is greater than or equal to about 1 millimeter.

11 . The apparatus of claim 1 wherein a distance between the vents along the length of the tube is in the range of 25 meters to 250 meters.

12 . A cable comprising:
an outer jacket having an outer surface and an inner surface and defining an interior volume bounded by the inner surface, the interior volume configured to be in fluid communication with a water body; a tube having a wall defining an interior volume of the tube and disposed within the interior volume of the outer jacket; one or more optical fibers disposed within the interior volume of the tube; wherein:
the wall of the tube includes a plurality of vents, each vent passing between an outer surface of the wall of the tube and the interior volume of the tube, the plurality of vents disposed along a length of the tube and having a distance therebetween; and
wherein each vent is configured to provide fluid communication between the interior volume of the outer jacket and the interior volume of the tube.

13 . The cable of claim 12 further comprising:
at least one strength member defining a central axis of the sensor cable and wherein the tube comprises a helicoid disposed about the strength member.

14 . The cable of claim 12 wherein the vents have a preselected population and size configured to provide a preselected flow rate into the interior volume of the tube.

15 . The cable of claim 14 wherein the preselected flow rate is equal to or greater than about 1000 cubic millimeters/sec.

16 . The cable of claim 12 wherein the outer jacket comprises a plurality of vents between the outer surface of the outer jacket and the interior volume of the outer jacket, the vents configured to provide fluid communication between the interior volume of the outer jacket and a water body in fluid communication with the outer surface of the outer jacket.

17 . The cable of claim 12 wherein the optical fibers comprise a buffer layer disposed on an outer surface of a primary polymer coating of the optical fiber.

18 . The cable of claim 12 wherein the distance between vents is in a range of 25 meters to 250 meters.

19 . The cable of claim 12 wherein the vents have a cross-sectional area equivalent to an area of a circle having a diameter equal to or greater than about 20 micrometers.

20 . The cable of claim 19 wherein the vents have a cross-sectional area equivalent to an area of a circle having a diameter greater than about 1 millimeter.

21 . A method comprising:
providing a fiber optic cable having seismic sensors connected to optical fibers, the fiber optic cable comprising:
an outer jacket having an outer surface and an inner surface and defining an interior volume bounded by the inner surface, the interior volume configured to be in fluid communication with a water body;
a tube having a wall defining an interior volume of the tube and disposed within the interior volume of the outer jacket;
one or more optical fibers disposed within the interior volume of the tube; wherein:
the wall of the tube includes a plurality of vents, each vent passing between an outer surface of the wall of the tube and the interior volume of the tube, the plurality of vents disposed along a length of the tube and having a distance therebetween; and
wherein each vent is configured to provide fluid communication between the interior volume of the outer jacket and the interior volume of the tube;

submerging the fiber optic cable in the water body; flooding an interior volume of the tube with water; and communicating a signal generated by the seismic sensors in response to a seismic event through the one or more optical fibers.

Assignees

• Pgs Geophysical As

Inventors

• Segsworth Matthew
• Smith Jeremy
• Fernihough Robert Alexis Peregrin
• Bowlus Jeff

Classifications

• G02B6/4431

  with provision in the protective covering, e.g. weak line, for gaining access to one or more fibres, e.g. for branching or tapping (break-out terminations G02B6/4471) · CPC title

• E21B47/113

  using electrical indications; using light radiations · CPC title

• G02B6/4429

  Means specially adapted for strengthening or protecting the cables · CPC title

• G02B6/4427 Primary

  Pressure resistant cables, e.g. undersea cables · CPC title

• G02B6/4434 Primary

  Central member to take up tensile loads · CPC title