Leak detection device, and coating intended for a fluid transport or storage member and comprising said detection device
View Patent ↗The invention relates in particular to a method of covering a duct for transporting or storing a fluid in a device for detecting a leak of the fluid, the device comprising a layer of insulating fibrous material arranged to surround the duct and a layer of conductive material that extends against the layer of insulating material, the conductive material being essentially constituted by fibers of carbon or graphite, wherein the layer of insulating material is secured to the wall of the duct by strapping ties around said layer.
1. A device for detecting a leak of a fluid that is stored or transported in a duct ( 10 ) having an electrically conductive outer wall ( 11 ), which duct is covered in a layer of insulating fibrous material ( 13 ) arranged to surround the duct, the device comprising:
a layer of conductive fibrous material ( 16 ) that extends against the layer of insulating fibrous material ( 13 ), the conductive fibrous material being constituted by a carbon or graphite felt;
a detector appliance ( 23 ) for detecting a short circuit or measuring impedence between the outer wall ( 11 ) of the duct and the layer of conductive fibrous material ( 16 );
a contact element ( 24 ) inserted or buried, at least in part, in the conductive fibrous material 916 ) in order to connect electrically the layer of conductive fibrous material ( 16 ) to the detector appliance ( 23 ); and
a layer of thermally insulating material ( 19 ) essentially constituted by fibers that extends against and surrounds the layer of conductive fibrous material ( 16 ).
2. A device according to claim 1 , wherein the insulating fibrous material ( 13 ) comprises silica fibers.
3. A device according to claim 1 , wherein the contact element ( 24 ) is made, at least in part, out of graphite or carbon.
4. A device according to claim 1 , wherein the contact element is in the form of a clamp having jaws capable of clamping onto a portion of the conductive fibrous material ( 16 ).
5. A device according to claim 1 , wherein the thickness of the layer of conductive fibrous material ( 16 ) is greater than or equal to about 5 millimeters.
6. A device according to claim 1 , wherein the thickness of the layer of conductive fibrous material ( 16 ) lies in a range from about 5 millimeters to about 10, 20, 30, or 50 millimeters.
7. A device according to claim 1 , wherein the thickness of the layer of insulating fibrous material ( 13 ) is less than 20 millimeters.
8. A device according to claim 1 , wherein the thickness of the layer of thermally insulating material ( 19 ) is greater than or equal to about 10 millimeters.
9. A device according to claim 1 , further including a rigid wall ( 20 ) arranged to surround or envelop the layer of thermally insulating material.
10. A device according to claim 9 , wherein the rigid wall is pierced by at least one orifice ( 21 ) suitable for passing a tool ( 22 ) for checking proper operation of the leak detector device through said wall and the layers of the covering of the duct.
11. A duct ( 10 ) for transporting or storing a heat-transfer fluid, the duct having an electrically conductive outer wall ( 11 ) and being covered in a layer of insulating fibrous material ( 13 ) arranged to surround the duct, the duct being fitted with a device for detecting a leak of the heat-transfer fluid, the device comprising:
a layer of conductive fibrous material ( 16 ) that extends against the layer of insulating fibrous material ( 13 ), the conductive fibrous material being constituted by a carbon or graphite felt;
a detector appliance ( 23 ) for detecting a short circuit or measuring impedence between the outer wall ( 11 ) of the duct and the layer of conductive fibrous material ( 16 );
a contact element ( 24 ) inserted or buried, at least in part, in the conductive fibrous material 916 ) in order to connect electrically the layer of conductive fibrous material ( 16 ) to the detector appliance ( 23 ); and
a layer of thermally insulating material ( 19 ) essentially constituted by fibers that extends against and surrounds the layer of conductive fibrous material ( 16 )
the duct having first ties ( 14 ) serving to secure the layer of insulating fibrous material ( 13 ) to the wall ( 11 ) of the duct.
12. A duct according to claim 11 and having second ties ( 17 ) serving to secure the layer of conductive fibrous material ( 16 ) to the duct covered in the insulating fibrous material ( 13 ).
13. A duct according to claim 11 , wherein the first ties are filamentary ties or in the form of cords and essentially constituted by fibers of electrically insulating material.
14. A method of covering a duct ( 10 ) for transporting or storing a heat-transfer fluid in a device that is for detecting a leak of the heat-transfer fluid, the duct having an electrically conductive outer wall ( 11 ) and being covered in a layer of insulating fibrous material ( 13 ) arranged to surround the duct, the device comprising:
a layer of conductive fibrous material ( 16 ) that extends against the layer of insulating fibrous material ( 13 ), the conductive fibrous material being essentially constituted by a carbon or graphite felt;
a detector appliance ( 23 ) for detecting a short circuit or measuring impedence between the outer wall ( 11 ) of the duct and the layer of conductive fibrous material ( 16 );
a contact element ( 24 ) inserted or buried, at least in part, in the conductive fibrous material 916 ) in order to connect electrically the layer of conductive fibrous material ( 16 ) to the detector appliance ( 23 ); and
a layer of thermally insulating material ( 19 ) essentially constituted by fibers that extends against and surrounds the layer of conductive fibrous material ( 16 );
wherein the layer of insulating fibrous material ( 13 ) is secured to the outer wall ( 11 ) of the duct by strapping first ties ( 24 ) around said layer.
15. A method according to claim 14 , wherein the layer of conductive fibrous material ( 16 ) is secured to the duct covered in the insulating fibrous material ( 13 ) by strapping second ties ( 17 ) around the layer of conductive fibrous material ( 16 ).
16. A method according to claim 14 , the method being performed on a duct for transporting sodium under pressure or on a container for storing sodium under pressure.
17. A method of checking proper operation of a leak detector device fitted to a duct—the duct having an electrically conductive outer wall ( 11 ) and being coated in a layer of insulating fibrous material ( 13 ) arranged to surround the duct, the leak detector device comprising a layer of conductive fibrous material ( 16 ) that extends against the layer of insulating fibrous material ( 13 ), the conductive fibrous material being essentially constituted by a carbon or graphite felt, wherein a short circuit is established between the wall ( 11 ) of the duct and the layer of conductive fibrous material ( 16 ).
18. A method according to claim 17 , wherein an electrically conductive tool ( 22 ) is inserted through the layer of conductive fibrous material ( 16 ) and through the layer of insulating fibrous material ( 13 ), and the tool ( 22 ) is put into contact with the conductive wall ( 11 ) of the duct while keeping said tool in contact with the layer of conductive fibrous material through which the tool ( 22 ) extends, in order to establish the short circuit and check that the leak detector system is operating properly by measuring the impedance between the wall of the duct and the layer of conductive fibrous material.
19. A method according to claim 18 , wherein the electrically conductive tool ( 22 ) is made of metal, in the form of a rod or a needle.
20. A method according to claim 17 , the method being performed on a duct for transporting sodium under pressure or on a container for storing sodium under pressure.