Protective socket for a sensor node
The present invention relates to a seismic cable ( 3 ) comprising at least two sensor nodes ( 4 ), the cable being adapted to lie permanently on a seabed ( 5 ). By covering each sensor node ( 4 ) and a length of the cable ( 3 ) connecting the sensor nodes ( 4 ) with a flexible protective socket ( 7 ), there is obtained a leak-tight connection, whereby penetration of water and/or moisture into the components of the sensor node ( 4 ) is not permitted.
1. A seismic cable for use on or close to a seabed comprising:
a cable, and
at least one sensor node connected to the cable and comprising:
a cylindrical sensor unit including a sensor,
at least one hydrophone,
a pair of end sides, each including a flange,
a pair of conical ring elements at opposite ends of the cylindrical sensor unit, each conical ring element having a first end abutting the flange of a respective end side and a second end arranged along a length of the cable, and
a flexible protective socket arranged around the cylindrical sensor unit, the conical ring elements, and parts of the cable, the flexible protective socket comprising:
a cylindrical central body connected at each end to a conical intermediate piece having a shape corresponding to a respective conical ring element,
wherein each conical intermediate pieces is terminated in a flexible end part,
wherein an inner surface of each end part forms a leak-tight connection around and along a length of an outer surface of the cable due to the flexibility of the end part.
2. A seismic cable according to claim 1 , wherein the sensor unit is made of a pressure-resistant material.
3. A seismic cable according to claim 1 , wherein the at least one hydrophone is housed in at least one of the conical ring elements.
4. A seismic cable according to claim 1 , wherein each conical ring element is filled with a material that is suitable for damping impacts or shocks.
5. A seismic cable according to claim 1 wherein each end side includes at least one of a lead-in and a connecting devices for at least one sub-cable.
6. A seismic cable according to claim 1 , wherein:
each end side includes at least one of a lead-in and a connecting device for at least one sub-cable, and
the sub-cables, in transitional areas between the sensor unit and each of the conical ring elements, are protected by a protective sleeve.
7. A seismic cable according to claim 1 , wherein the cable extends a length within each of the conical ring elements.
8. A seismic cable according to claim 1 , wherein the protective socket is configured in several pieces, the pieces being arranged so as to obtain leak-tight protection around the cable and conical ring elements.
9. A seismic cable according to claim 1 , wherein a cover is arranged over the protective socket.
10. A sensor system for use on or near a seabed, comprising:
at least one sensor node connected to a cable and comprising:
a cylindrical sensor unit including a sensor,
at least one hydrophone,
a pair of end sides, each including a flange,
a pair of conical ring elements at opposite ends of the cylindrical sensor unit, each conical ring element having a first end abutting the flange of a respective end side and a second end arranged along a length of a cable, and
a flexible protective socket arranged around the cylindrical sensor unit, the conical ring elements, and parts of the cable, the flexible protective socket comprising:
a cylindrical central body connected at each end to a conical intermediate piece having a shape corresponding to a respective conical ring element,
wherein each conical intermediate pieces is terminated in a flexible end part,
wherein an inner surface of each end part forms a leak-tight connection around and along a length of an outer surface of the cable due to the flexibility of the end part.