Detector of water-based solution leaks

Abstract

A detection system (S) for detecting water-based leaks, i.e., conductive liquids, which is installable on an element (E) to be monitored in a plant, comprises a detection device (20) and at least one sensor cable (40) to be positioned on said element (E) to be monitored. There are signaling elements (50, 52, 60) which are used to signal possible leaks detected by the sensor cable (40). The device (20) comprises a power and connection connector (70) for powering the detection device (20) and the signaling elements (50, 52, 60) also adapted to allow the communication of the detection device (20) with an operating control room and / or supervision systems. The sensor cable (40) comprises a sensing part (42) and a non-sensing part (41), and the sensing part (42) of the sensor cable (40) comprises a central portion (CC) made of conductive material and an outer protective sheath (G) which is electrically insulating and permeable to water and to water-based liquids. The detection device (20) comprises a processing unit (21) adapted to receive the signals generated by the sensor cable (40), to process them and to decide, based on calibration parameters and based on thresholds defined by the sensitivity set for the detection device (20), whether a leak has been detected or not through detecting a variation in the resistance of the sensor cable (40) due to the presence of water-based liquids on said sensing part (42), and if so, the processing unit (21) is adapted to activate the signaling elements (50, 52, 60) and the communication elements (70) communicating with the control room and / or the supervision systems for requesting maintenance on the monitored element (E).

Description

[0001] DETECTOR OF WATER-BASED SOLUTION LEAKS

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to the field of water-based leak detectors.

[0004] In particular, the present invention relates to a detector of water-based solution leaks, i.e. , of conductive liquids, in the residential, industrial and agricultural fields, applicable to all types of plant elements (valves, filters, flanges, pump bodies, tanks, piping, etc.) with or without insulation elements.

[0005] PRIOR ART

[0006] At present, it is possible to detect the presence of leaks only by performing continuous visual and / or tactile-manual inspections on the possible points subject to any leaks of liquids or fluids, which may be all the junction elements of valves, filters, flanges, pump bodies, tanks, piping, couplings, etc.

[0007] Obviously, these inspections shall be performed in compliance with the safety regulations for inspection personnel.

[0008] Such activity therefore requires employing maintenance personnel adapted for the surveillance of the plant elements which may be subject to leaks of water-based liquids.

[0009] In the event of detecting a leak of liquids, it will be necessary that the personnel who identified the leak promptly report the event, highlighting the leaking element in a clear manner for the appropriate maintenance interventions.

[0010] Obviously, thereby, there will be an enormous request for personnel for the work of manual leak detection, with a clear expenditure of time and with the need for shifts covering the entire span of the day and night to have continuous monitoring.

[0011] For detecting leaks of water-based liquids or fluids, the current technological system therefore provides for a manual detection of the visual and / or tactile-manual type (in compliance with safety regulations) at one or possibly more time instants.

[0012] The same limits of the visual / tactile action make a continuous cyclic detection for prolonged periods of time problematic, such as in the case of constant monitoring, in addition to the evident difficulty of a timely detection with possible presence of insulation applied to the element which is the object of the inspection and monitoring. In particular, the limitations of the manual mode are: the difficulty of visually identifying light leaks in the event of an uninsulated element, the impossibility of promptly detecting liquid leaks in the presence of insulation systems which especially “hide” light or modest leaks, the difficulty in detecting the leak, even a significant one, in areas that are difficult to reach by the assigned personnel, the impossibility of manual tactile detection, when necessary, in the case of plant elements with elevated operating temperatures, the hazardousness of verification operations in the presence of environments with elevated temperatures and / or other critical issues for personnel safety, as well as in the presence of corrosive or hazardous liquids, the reporting of the event with a swift and clear identification of the element subject to leaks for the assigned maintenance personnel.

[0013] SUMMARY OF THE INVENTION

[0014] The detection of any leaks of water-based liquids or fluids, i.e., conductive liquids, from a plant element with or without insulation, is carried out by applying a hardware device which, by virtue of the use of specific sensor cables and indicator lights, promptly identifies any presence of liquid leaks.

[0015] The detection, performed by the hardware device, of any leaks of water-based liquids, i.e., of conductive liquids, of a plant element, promptly identifies any presence of liquid leaks, signaling the event by interfacing with the available networks and / or supervision and control rooms and, locally, it enables signaling by means of indicator lights.

[0016] The detector includes from 1 to n leak sensors for water-based solutions.

[0017] In particular, the detector enables real-time verification of any leaks of water-based solutions on hot lines (temperature up to +450°C).

[0018] With the leak detector according to the present invention, it is possible to verify, in real-time, any leaks of liquids consisting of water-based solutions on hot lines for all plant elements in the residential, industrial and agricultural field, of any form, also in the presence of insulation with insulating material of any type and mode (movable or fixed, soft or rigid).

[0019] The object of the invention has been achieved by a water-based leak detection system, installable on an element to be monitored, as defined in claim 1 .

[0020] In particular, the present invention relates to a detection system for water-based leaks, i.e., conductive liquids, installable on an element to be monitored in a plant. The system comprises a detection device and at least one sensor cable to be positioned on the element to be monitored, in which signaling elements are present which are used to signal any leaks detected by the sensor cable. The device comprises a power and connection connector for powering the detection device and the signaling elements and is also adapted to allow the communication of the detection device with an operating control room and / or supervision systems. The sensor cable comprises a sensing part and a non-sensing part, in which the sensing part of the sensor cable comprises a central portion made of conductive material and an outer protective sheath which is electrically insulating and permeable to water and to water-based liquids, i.e., conductive liquids. The detection device comprises a processing unit adapted to receive the signals generated by the sensor cable, to process them and to decide, based on calibration parameters and based on thresholds defined by the sensitivity set for the detection device, whether a leak has been detected or not through detecting a variation in the resistance of the sensor cable due to the presence of water-based liquids on the sensing part, and if so, the processing unit is adapted to activate the signaling elements and the communication elements communicating with the control room and / or the supervision systems for requesting maintenance on the monitored elements.

[0021] Preferably, the system comprises a container for housing the detection device and at least one connector for said at least one sensor cable, in which, on the outer portion of the container, signaling elements are present, which are used to signal possible leaks detected by the sensor cable on the element to be monitored.

[0022] The detection device is provided with an electronic processing unit provided with processing capability and an integrated software component for detecting leaks based on the sensitivity set for the detection device.

[0023] The system comprises a plurality of sensor cables with respective connectors adapted to be connected to respective connection ports provided on the container and in communication with the detection device for the transmission of the measurements.

[0024] A plurality of signaling elements is present on the outer portion of the container, whereby each signaling element is turned on or flashed when the respective sensor cable detects a leak on the monitored element. The detection system is powered by the mains power supply by means of the power and connection connector connected to a power and connection port which also allows, in addition to the power supply, to put the leak detection system in communication with an operating control room and / or with supervision systems.

[0025] The detection system comprises, on the outer portion of the container, for example, two configuration buttons used to set the sensitivity of the sensor cable and the network identification address of the leak detection system.

[0026] The container is made with IP67 rating of protection or higher.

[0027] The sensing part and the non-sensing part of the sensor cable are connected to each other by means of a silicone-coated soldering or by means of a two-pole connector, with IP67 protection or higher, resistant to temperatures from -40°C to +80°C.

[0028] The non-sensing part of the sensor cable, for example, comprises the central portion of conductive material, made of a two-conductor cable and the electrically insulating, impermeable outer protective sheath made of a silicone sheath.

[0029] The sensing part of the sensor cable comprises the central portion made of conductive material made by two conductors individually sheathed, for example, with a fiberglass sheath permeable to liquids, in which the two conductors are intertwined with one another.

[0030] The sensing part of the sensor cable comprises an insulation terminal resistant to temperatures from -40°C to +450°C applied to the free end, in an opposite position with respect to the end connected to the non-sensing part.

[0031] The sensor cable, if hit by water or water-based liquids, i.e., conductive liquids, changes its resistance or conductivity, detecting an anomaly, i.e., a loss of waterbased liquids, in which such anomaly is recognized by the detection device as a variation in the resistance of the sensor cable and signaled by means of the signaling elements.

[0032] The central portion of the sensor cable is made of any conductive material selected from copper, aluminum, stainless steel, graphite and conductive alloys, and other conductive materials in general.

[0033] The outer sheath is made of a material selected from glass fiber, porous rubber, porous ceramics, fibrous materials and porous polymers, and other electrically insulating and liquid-permeable materials in general. In the presence of insulation on the element to be monitored, the sensor cable must be positioned under the insulation, i.e. , in direct contact with the bare element to be monitored.

[0034] When the sensor cable is worn, given the modularity thereof, it may be replaced quickly and easily.

[0035] The present invention also provides a method for detecting water-based leaks for an element to be monitored in a plant.

[0036] BRIEF DESCRIPTION OF THE FIGURES

[0037] In the following description, reference will be made to the Figures shown in the accompanying drawings, in which:

[0038] Figure 1 shows a device according to the present invention,

[0039] Figures 2, 3 and 4 show the device of Figure 1 with the sensor cables and application examples,

[0040] Figure 5 shows details of a portion of a sensor cable,

[0041] Figures 6 and 7 show block diagrams of the operation of the device, and

[0042] Figure 8 shows a flow diagram of the operation of the device.

[0043] The parts according to the present description are depicted in the drawings, where appropriate, using conventional symbols, showing only the specific details relevant to understanding the embodiments of the present invention, so as not to highlight details, which will be immediately apparent to those skilled in the art, with reference to the description provided below.

[0044] DETAILED DESCRIPTION OF THE INVENTION

[0045] The solution according to the present invention will now be described with the aid of the drawings.

[0046] Liquid leak sensors are used to detect the presence of liquids in areas in which liquids should not be present. To construct these sensors, conductive materials are used which respond to the presence of conductive liquids by completing or “closing” an electrical circuit or by modifying an electrical property of the sensor itself, such as resistance or capacitance.

[0047] Resistive sensors measure the electrical resistance between two points. When a conductive liquid is present, the electrical resistance between the contact points changes, indicating the presence of a leak. The solution proposed herein provides for the use of a detector of water-based solution leaks in the residential, industrial and agricultural field, applicable to all types of junction elements of valves, filters, flanges, pump bodies, tanks, piping, etc. with or without insulation elements, which includes sensor cables for leaks of waterbased solutions, i.e., conductive solutions.

[0048] The detector thus implemented enables a real-time verification of any leaks of waterbased solutions on all types of plant elements.

[0049] In particular, the leak detection device in accordance with the invention may be used on hot lines with operating temperatures up to +450°C.

[0050] The leak detection device in accordance with the invention allows verifying, in real time, the presence of any leaks of liquids or fluids consisting of water-based solutions on elements E of hot lines, in particular for all plant elements E in the residential, industrial and agricultural field of any form, also in the presence of insulation CO with insulating material of any type and mode (movable or fixed, soft or rigid insulation element).

[0051] The leak detection system therefore comprises a hardware component powered by a +12 / 24 V electrical network, an electronic device with processing capability, and a software component (firmware) integrated therein.

[0052] The device, suitably initialized with parameters such as sensor sensitivity and the possible assignment of an identification address for interfacing to the industrial control and supervision communication network, consists of sensor cables to be applied on points deemed subject to possible leaks, and acquires as input the voltage and electrical resistance values measurable by the sensor cables, and processes them, communicating a result by means of the control and supervision network to which it is possibly connected and, locally, by means of indicator lights.

[0053] The leak detection system S comprises a container 10 for obtaining the housing for a detection device 20 and for a plurality of connectors 30 for a corresponding plurality of sensor cables 40 which will be positioned on an element E to be monitored.

[0054] The leak detection system S therefore comprises a detection device 20 provided with a hardware part or electronic processing unit 21 provided with processing capability, and which includes an integrated software (firmware) component 22.

[0055] The leak detection system S is powered by the mains power supply. In particular, Figure 1 shows a leak detection system S, provided with three sensor cables 40a, 40b, and 40c, with respective connectors 30a, 30b, and 30c adapted to be connected to respective connection ports 32a, 32b, and 32c arranged on the container 10 and in communication with the detection device 20.

[0056] On the outer portion of the container 10, there are further signaling elements, such as, for example, status LEDs 50 and 52, which are used to provide information on the operation of the detection device 20.

[0057] Also, on the outer portion of the container 10, there are also signaling elements 60, such as, for example, signaling LEDs 60 which may be turned on or flashed when the respective and corresponding sensor cables 40 detect a leak on the monitored element E.

[0058] In particular, Figure 1 shows an example in which three signaling LEDs 60a, 60b and 60c are present, respectively connected to the three sensor cables 40a, 40b and 40c, provided with respective connectors 30a, 30b and 30c, adapted to be connected to the respective connection ports 32a, 32b and 32c.

[0059] The leak detection system S is powered by the mains power supply by means of a connector 70 connected to a power and connection port 72 which also allows, in addition to the power supply, to put the leak detection system S in communication, for example, with operating control rooms and supervision systems.

[0060] On the outside of the container 10 there are also two configuration buttons 80 and 82, used to set the sensitivity of the sensors 40 and the network identification address of the leak detection system S.

[0061] The detection device 20 is housed in the container 10, which is made with IP67 rating of protection or higher. The detection device 20 comprises an electronic processing unit 21 which may be powered by the mains power supply at +12V / +24 V and a management software.

[0062] The container 10 is provided with a plurality of connection ports 32 to which it is possible to connect a plurality of sensor cables 40 for detecting leaks of liquids consisting of water-based solutions (conductive liquids).

[0063] The detection device 20 may operate indifferently with one or with a plurality of connected sensor cables 40. Figures 1 and 2 show an example in which the leak detection system S includes a detection device 20 with three connection ports 32. The container 10 also comprises a power and connection port 72 with the dual function of inlet for the electric power supply originating from the electrical network and network communication.

[0064] Two buttons 80 and 82 for the configuration of the device 20 are available outside the container 10, and close to the connection port 72, with which it is possible to set the sensitivity of the sensor cables 40 and the identification address of the device 20 in the network.

[0065] The container 10 comprises status LEDs 50 and 52 and, in the specific case shown, three signaling LEDs 60a, 60b and 60c associated with the respective three sensor cables 40a, 40b and 40c.

[0066] Obviously, Figures 1 and 2 are purely for illustrative purposes. The leak detection system S may undergo modifications in the shape, size, and layout of the components (connectors 30, status LEDs 50 and 52 and signaling LEDs 60a, 60b, and 60c, buttons 80 and 82, connector 70).

[0067] With particular reference to Figures 2, 3 and 4, the sensor cables 40 consist of a non-sensing part 41 of variable length depending on the size of the area of the element E to be monitored and which serves as a connection with the detection device 20, and of a sensing part 42, in which the two sensing 42 and non-sensing 41 parts, are connected to each other by a connector 43.

[0068] Preferably, the non-sensing part 41 of the sensor cable 40 may be provided directly by the user, who sizes it based on the application.

[0069] Figures 3 and 4 show examples of elements E1 , E2 and E3 to be monitored to detect possible water-based liquid leaks.

[0070] In particular, Figure 4a shows the solution in the absence of insulation CO, while Figure 4b shows an example in the presence of insulation CO on the elements to be monitored.

[0071] The non-sensing cable part 41 is connected by means of a two-pole connector 43 with IP67 protection or higher to the sensing part 42. In particular, the non-sensing cable part 41 is made, for example, of a cable with two conductors coated with a double silicone sheath resistant to temperatures from -40°C to +200°C.

[0072] At the other end, the non-sensing cable part 41 is connected by means of the connector 30 to the connection port 32 arranged on the container 10. Given the multiple possibilities of use of the leak detection system S, the length of the sensor cables 40 may vary greatly in the various applications, and therefore it is possible to customize the length of the non-sensing cable part 41 depending on the customer and on the size of the area to be monitored. Conventionally, the nonsensing cable part 41 is directly arranged by the end user, who sizes it based on the requirements.

[0073] In order to make the leak detection system S adaptable and customizable to the various and different applications, connectors 30 and 43 have been provided.

[0074] The sensing part 42 and the non-sensing part 41 may be joined to each other by means of a silicone-coated soldering or by means of joints or connectors 43 with IP67 rating of protection or higher, resistant to temperatures from -40°C to +80°C.

[0075] The sensing part 42 of the cable, resistant to temperatures from -40°C to +450°C, consists of two conductors individually sheathed with a liquid-permeable sheath, for example made of fiberglass, in which the two conductors are intertwined with one another, plus an insulation terminal 44 applied to the free end of the sensing part 42 of the sensor cable 40, in a position opposite with respect to the end connected to the non-sensing part 41 .

[0076] The insulation terminal 44 insulates the exposed end of the sensing part 42 of the cable not covered by the liquid-permeable sheath, for example, made of fiberglass. Operating modes of the leak detection system S are now described. The leak detection device 20 provides two operating modes: the configuration mode and the detection mode.

[0077] At the startup of the system S, the leak detection device 20 enters by default in detection mode. In this mode, the device 20 is operational and ready to detect any leaks on the basis of factory settings.

[0078] The status LEDs 50 and 52 indicate the operating status of the system S, i.e. , normal operation and general detected leak alarm, while the signaling LEDs 60a, 60b and 60c indicate, for each specific sensor cable 40a, 40b and 40c, the presence of a leak. In particular, each LED 60i will start to flash if a possible leak is detected by the corresponding sensor cable 40i.

[0079] The configuration mode allows setting the detection sensitivity of the sensor cables 40a, 40b and 40c and / or assigning the identification address of the leak detection device 20 in the communication network to which it connects. These two operating modes may be activated by means of the configuration buttons 80 and 82 present on the container 10 of the leak detection device 20.

[0080] To access the sensitivity setting procedure of the sensor cables 40a, 40b and 40c, it is necessary to keep a first button 80 of the device pressed until the two status LEDs 50 and 52 will start flashing rapidly together for a few moments, thus indicating access to the sensitivity setting mode.

[0081] In this mode, it is possible to modify the sensitivity level of the detector, with respect to the presence of liquids and the related exposure time, again by pressing the first button 80.

[0082] Three sensitivity levels are available for the sensor cables 40a, 40b and 40c:

[0083] Low Sensitivity: for this sensitivity level, the leak presence alarm will be triggered following the exposure of the sensing part 42 of the sensor cable 40 to greater quantities of leaks and greater exposure time with respect to the other sensitivity levels (medium and high). This low sensitivity level is indicated by the leak detection device 20 with the two status LEDs 50 and 52 both blinking in the setting mode;

[0084] Medium Sensitivity: for this sensitivity level, the alarm will be triggered following the exposure of the sensing part 42 of the sensor cable 40 to medium quantities of leaks and medium exposure time with respect to the other sensitivity levels (low and high). This medium sensitivity level is indicated by the leak detection device 20 with the status LED 50 blinking in setting mode;

[0085] High Sensitivity: for this sensitivity level, the alarm will be triggered following the exposure of the sensing part 42 of the sensor cable 40 to minimum quantities of leaks and minimum exposure time with respect to the other sensitivity levels (low and medium). This level is indicated by the leak detection device 20 with the status LED 52 blinking in setting mode.

[0086] For example, the two status LEDs 50 and 52 have different colors to indicate the different sensitivity modes set; in particular, status LED 50 is a green LED, and status LED 52 is a red LED.

[0087] Once the desired sensitivity level has been selected, without further pressing the keys 80 and 82, after ten seconds the two status LEDs 50 and 52 will start flashing rapidly for a few moments, indicating the storage of the set sensitivity level, with the exit from the configuration mode, and the return to the usual detection mode. The leak detection device 20 enables interfacing with the control and supervision systems of the industrial plant to be monitored by means of various communication protocols possibly available on the network.

[0088] To allow the correct connection to the industrial control networks, it is necessary to assign an identification address of the leak detection device 20.

[0089] To activate the network address assignment procedure, it is necessary to keep the second button 82 pressed until the two status LEDs 50 and 52 will start flashing rapidly together for a few moments, thus signaling the access to the identification address assignment mode.

[0090] At this point it is possible to set the address using both buttons 80 and 82 and more precisely:

[0091] - by means of the first button 80, the tens value of the address is set (by pressing repeatedly, the tens value is increased by tens); and

[0092] - by means of the second button 82, the unit value of the address is set (by pressing repeatedly, the unit value is increased by units).

[0093] Once the desired address has been assigned, without further pressing on buttons 80 and 82, after ten seconds the two status LEDs 50 and 52 will start flashing rapidly for a few moments, indicating the storage of the set address, with the exit from the configuration mode, and the return to the usual detection mode.

[0094] The setting of the network identification address may also be assigned via software or by means of a PLC plant supervision system.

[0095] The device 20 includes the two status LEDs 50 and 52, respectively green and red in color, by way of non-limiting example, which provide information on the operation of the device 20 and on the operating settings.

[0096] The leak detection device 20 further provides a plurality of signaling LEDs 60i, red in color, specific for each sensor cable 40i and located at each connector 30i of the corresponding sensor cable 40i.

[0097] In detection mode, the two status LEDs 50 and 52 indicate the status of the device and, in particular, the following exemplary conditions may occur: status LED 50, green in color, blinking every ten seconds, status LED 52, red in color, always off: it indicates that the system S is ready for leak detection and the operation thereof is regular; status LED 52, red in color with fast blinking for a duration of twelve seconds alternating with four seconds of status LED 52, red in color, off: indicates that the system S has detected a leak.

[0098] Obviously, the devices according to the present invention may have colors and sequences of variable intermittency and of different durations with respect to those just described, by way of non-limiting example.

[0099] With regards to the signaling LEDs 60i, each LED 60i, associated with a corresponding sensor cable 40i, will start to flash only when a leak is detected by the corresponding sensor 40i.

[0100] This type of architecture provides a leak detection device 20 which is easily installable in any part of a plant to be controlled and monitored.

[0101] The detection device 20, contained in the container 10 and provided with at least one sensor cable 40 which may be installed at sensing points of the plant for monitoring and detecting leaks.

[0102] In particular, the status LEDs 50 and 52 present on the container 10, and therefore visible from the outside, may be used for signaling any anomalies, i.e., in the presence of detected leaks.

[0103] Alternatively, or in addition, it is possible to also provide the connection with a control room and supervision systems, in which personnel adapted to control the various leak detection devices 20 employed in a plant is present.

[0104] For example, supervision system means a panel-mounted console or control unit arranged in an area of the plant easily accessible to the operators.

[0105] In particular, in the solution proposed herein, a sensor cable 40 is a section of cable which constitutes the sensor and has a non-sensing part 41 and a sensing part 42 connected to each other, for example, by means of a connector 43. The sensing part 42 of the sensor cable 40 has a central portion CC made of conductive material and an external protective sheath G which is permeable to water or to water-based liquids, i.e., conductive liquids. The non-sensing part 41 also has a central portion CC made of conductive material and an external, water-impermeable protective sheath GL

[0106] In particular, the outer sheath G acts as a protective element against false contacts of the central portion CC, and, at the same time, is permeable to water or to waterbased liquids. For example, the outer sheath G may be made of fiberglass, so as to insulate the central portion CC from any contacts with metal elements during the installation step or during leak monitoring, while however allowing water, possibly present in the event of leaks, to pass. The sensor cable 40, if exposed to water or water-based liquids, i.e. , conductive liquids, changes the resistance or conductivity thereof, thus detecting an anomaly, i.e., a leak of water-based liquids.

[0107] In particular, the sensor cable 40, if exposed to water or water-based liquids, i.e., conductive liquids, changes the resistance or conductivity thereof without however varying the shape and size thereof.

[0108] When the sensor cable 40 comes into contact with water or other water-based liquids (which are conductive), a conductive bridge is formed.

[0109] This lowers the resistance (or increases the conductivity) of the sensor cable 40.

[0110] Such anomaly is recognized by the detection device 20 as a variation in the resistance of the sensor cable 40 and is signaled by means of the status LEDs 50,52 and / or the signaling LEDs 60a, 60b and 60c.

[0111] Therefore, the sensor cable 40 is the detection element of the system S and how it is constructed is important.

[0112] The central portion CC is made of any conductive material, such as copper, aluminum, stainless steel, graphite, and conductive alloys.

[0113] Copper is a highly effective and common conductor. It is often used in leak sensors for the relatively low costs and ease of processing thereof.

[0114] Aluminum is another conductive material which is frequently used. It is lighter than copper and is more resistant to corrosion in some environments, which may be an advantage for leak sensors in aggressive environments.

[0115] Stainless steel is used for leak sensors in corrosive environments or where greater resistance and durability are required.

[0116] Graphite is a conductor used in applications in which a low cost and greater resistance to corrosion are required.

[0117] Some conductive alloys, such as brass or bronze, may be used for specific applications. They are often selected for the mechanical properties thereof or for corrosion resistance.

[0118] In particular, much importance and attention must be given to the selection of the outer sheath G, which shall have two fundamental features, i.e., isolating the central portion CC, made of conductive material, from contact with other metal parts and, at the same time, being permeable to water or to water-based fluids or liquids, i.e. , conductive liquids. Consequently, the material selected to make the outer sheath G shall possess the properties of being an electrical insulator permeable to water and to water-based solutions. Example of materials adapted for making the outer sheath G are fiberglass, porous rubber, porous ceramic, fibrous materials and porous polymers.

[0119] Examples of fibrous materials are felt or certain types of technical fabrics which are electrically insulating, but allow the passage of liquids.

[0120] Furthermore, some porous polymers, such as expanded polyethylene or porous polypropylene, are capable of electrically insulating while allowing liquids to pass therethrough.

[0121] This solution is used for the detection of conductive fluids, such as water-based solutions, i.e., of fluids which are conductive.

[0122] The solution described herein provides at least one independent connection 32 for each sensor cable 40.

[0123] The sensor cable 40 is also used for detecting leaks at valve heads or bleed screws, also in the presence of gaskets or insulation CO.

[0124] As already indicated, the leak detection device 20 is applicable to any element E possibly subject to leaks, such as bare or insulated connection elements.

[0125] Obviously, in the event of presence of insulation CO, the leak detection device 20, and, in particular, the sensor cables 40, shall be positioned under the insulation CO, i.e., in direct contact with the bare element E to be monitored.

[0126] The sensor cable 40 is therefore provided with a sensing end part 42.

[0127] The sensor cable 40 is subject to wear due to the particular use for which it is intended.

[0128] Therefore, it is appropriate to provide solutions in which it is possible to replace the worn sensor cable 40 quickly and simply. For this reason, the sensor cable 40 is modular, so as to replace only the worn part.

[0129] In particular, the sensor cable 40 includes the central portion CC made of conductive material along the entire cable 40 and a first impermeable sheath Gl (for example, a silicone sheath) for a non-sensing part of the cable 41 so as to make that part of the cable impermeable, i.e., not sensitive to liquids, and a sensing end portion 42 covered by the outer sheath G permeable to water or to water-based liquids, in which the outer sheath G permeable to water is electrically insulating.

[0130] The detection device 20 comprises a processing unit 21 that receives the signals generated by the sensor cables 40, it processes them, and decides whether a loss has been detected, i.e., a variation in the resistance of the sensor cables 40 due to the presence of liquids in the end portion 42 covered by the outer sheath G permeable to water or to water-based liquids, i.e., conductive liquids, which is, at the same time, electrically insulating.

[0131] Obviously, the detection device 20 shall be calibrated so as not to indicate false positives, i.e., detecting leaks in the presence of only a couple of drops, for example of condensation.

[0132] Thereby, the detection device 20 is calibrated and adjusted, and some thresholds are defined to define the sensitivity of the detection device 20.

[0133] Such thresholds are communicated to the processing unit 21 , which uses them to decide whether or not to signal the presence of leaks.

[0134] The fastening of the sensor cable 40, at the sensing part 42 thereof, to the element E to be monitored shall be carried out using fastening elements such as special adhesive tapes or non-metallic clamps.

[0135] Obviously, depending on the condition of use of the detection device 20, i.e., in the event of elevated temperatures or the presence of acidic or corrosive substances, the fastening elements shall be selected with care.

[0136] The sensor cable 40 may be made on the basis of the indicated features, or commercial cables may be used (which are usually insulated and waterproofed) which are customized based on the specific requirements of the environment in which it must be installed.

[0137] The leak detection device 20, suitably initialized with the parameters PP characterizing the application scenario, such as the setting of the sensitivity of the sensor cables 40 to be applied on the points deemed subject to possible leaks, acquires, as input, the electrical resistance values RR measurable by the sensor cables 40 and processes them, returning a coded result based on whether or not a leak is detected.

[0138] In particular, the processing unit 21 , on the basis of the input parameters as the characterizing parameters PP and the measured electrical resistance values RR, performs the processing and outputs a value W that indicates the presence or the absence of leaks. Such value W is used to control the signaling LEDs 60.

[0139] Figure 6 shows a block diagram representing the block INPUT, consisting of all the system parameterization data and the measurements performed, the processing block ELAB, relating to the processing performed by the device 20 on the basis of the input data, and finally the block OUTPUT, consisting of the visual status signals by means of the signaling LEDs 60 and the communication of the detected event of a leak via the network to the control rooms or supervision systems by means of the connector 70.

[0140] In Figure 7, the input block INPUT shows the input data consisting of the communication parameters, the application-specific parameters (sensitivity of the sensors 40) of an element of any shape and size (in the residential, industrial and agricultural field, for example, valves, tanks, pipes, filters, flanges, etcetera), and the voltage and electrical resistance of the sensor cables 40 placed at appropriate points outside the element E.

[0141] The processing device 20 proceeds with processing of the input data according to a specific algorithm and returns the results, as shown in the block OUTPUT, represented by a status message visually signaled by means of the LED indicator lights LEDN 60 and transmitted by means of the connection 70 to the available control and supervision network, indicating the operating status of the leak detection device 20 and any alarms for detected leaks.

[0142] The messages sent indicate the operating status of the leak detection device 20, and any alarms for leaks detected by the sensors 40, with the indication of the sensor 40i which has detected the leak.

[0143] Figure 8 shows the flow diagram underlying the data processing algorithm executed by the processing unit 21 contained in the leak detection device 20.

[0144] In a first step 100, the initialization parameters of the sensors 40 are set. In a step 102, the voltage and the electrical resistance are measured by means of the sensor cable 40. In step 104, the measured values are checked. In the event of a normal situation, steps 102 and 104 are repeated until, during a step 106, a leak is detected and the visual signals and the communication messages on the operating status of the device 20 are activated. The solution described herein allows the possibility of continuously monitoring any liquid leaks, with a reduction in signaling times and in consequent maintenance intervention times.

[0145] Furthermore, there is a high reduction of the risks associated with leak control in environments critical for the health of the operators.

[0146] The structure of the system allows to easily identify the element subject to the leak by maintenance personnel by virtue of remote signaling by means of connection to the supervision and control network and, locally, by visual signaling, by means of LED indicator lights, with a consequent reduction in maintenance costs.

[0147] Finally, an economic saving is possible due to the immediate detection of leaks of expensive liquids.

[0148] Based on the specific application requirements, the leak detection device provides variants with respect to the standard version, employing an integrated display for use on cold lines, with the addition of pH indicator sensors in the event of fluid leaks from components in chemical plants, or of dedicated sensors for leaks of other non- water-based liquids, and, finally, advanced network connectivity.

[0149] The solution described herein allows to have the possibility of a continuous monitoring of possible liquid leaks, with a reduction in signaling times, a decrease in intervention times, a reduction in risks related to the control of leaks in environments critical for the health of the operators, ease of identification of the element E subject to leak by maintenance personnel by virtue of visual signaling, with a consequent reduction in maintenance costs.

[0150] Based on specific application requirements, the device provides variants with respect to the base version, for example, in some embodiments it is possible to provide an integrated display, for employing on cold lines, with the addition of pH indicator sensors in the event of fluid leakage from element E, or dedicated sensors for leaks of other non-water-based liquids, and finally, network connectivity.

[0151] The above description of embodiments of the invention is capable of showing the invention from a conceptual point of view so that others, using the prior art, will be able to modify and / or adapt in various applications such specific embodiments without further research and without departing from the inventive concept, and thus it is understood that such adaptations and modifications will be considered as equivalents of the specific embodiments. The means and materials for achieving the various functions described can be of a various nature, without thereby departing from the scope of the invention.

[0152] The terminology or expressions used are intended to be only descriptive and therefore non-limiting. Obviously, without prejudice to the principle of the invention, the construction details and the embodiments may vary widely with respect to what is described and illustrated above byway of example, without departing from the scope of the present invention.

[0153] Where the constructional features and techniques mentioned in the following claims are followed by reference symbols or numerals, such reference symbols were introduced for the sole purpose of increasing the intelligibility of the claims themselves, and accordingly such reference symbols have no limiting effect on the interpretation of each element identified by way of mere example by such reference symbols.

Claims

CLAIMS1) A detection system (S) for detecting water-based leaks, i.e., conductive liquids, which is installable on an element (E) to be monitored in a plant, wherein said system comprises a detection device (20) and at least one sensor cable (40) to be positioned on said element (E) to be monitored, wherein there are signaling elements (50, 52, 60) which are used to signal possible leaks detected by the sensor cable (40), wherein the device (20) comprises a power and connection connector (70) for powering the detection device (20) and the signaling elements (50, 52, 60), wherein said connector (70) is also adapted to allow the communication of the detection device (20) with an operating control room and / or supervision systems, wherein said sensor cable (40) comprises a sensing part (42) and a nonsensing part (41), and wherein said sensing part (42) of the sensor cable (40) comprises a central portion (CC) made of conductive material and an outer protective sheath (G) which is electrically insulating and permeable to water and to water-based liquids, i.e., conductive liquids, wherein said detection device (20) comprises a processing unit (21) adapted to receive the signals generated by the sensor cable (40), to process them and to decide, based on calibration parameters and based on thresholds defined by the sensitivity set for the detection device (20), whether a leak of water-based liquids, i.e., conductive liquids, has been detected or not through detecting a variation in the resistance of the sensor cable (40) due to the presence of water-based liquids on said sensing part (42), and if so, said processing unit (21) is adapted to activate the signaling elements (50, 52, 60) and the communication elements (70) communicating with the control room and / or the supervision systems for requesting maintenance on the monitored element (E).2) The detection system (S) according to claim 1 , wherein said system (S) comprises a container (10) for housing the detection device (20) and at least one connector (30) for said at least one sensor cable (40), wherein, on the outer portion of the container (10), signaling elements (50, 52, 60) are present, which are used to signal possible leaks detected by the sensor cable (40) on the element (E) to be monitored.3) The detection system (S) according to claim 1 or claim 2, wherein the detection device (20) is provided with an electronic processing unit (21) providedwith processing capability and an integrated software component (22) for detecting leaks based on the sensitivity set for the detection device (20).4) The detection system (S) according to any one of the preceding claims 2-3, wherein said system comprises a plurality of sensor cables (40a, 40b, 40c) with respective connectors (30a, 30b, 30c) adapted to be connected to respective connection ports (32a, 32b, 32c) arranged on said container (10) and in communication with the detection device (20) for transmitting the measurements.5) The detection system (S) according to claim 4, wherein a plurality of signaling elements (60) is present on the outer portion of the container (10), wherein each signaling element (60a, 60b, 60c) is turned on or flashed when the respective sensor cable (40) detects a leak on the monitored element (E).6) The detection system (S) according to any one of the preceding claims, wherein the detection system (S) is powered by the mains power supply by means of said power and connection connector (70) connected to a power and connection port (72) which also allows, in addition to the power supply, to put the leak detection system (S) in communication with an operating control room and / or with supervision systems.7) The detection system (S) according to any one of the preceding claims, wherein the detection system (S) comprises, on the outer portion of the container (10), at least two configuration buttons (80, 82) used to set the sensitivity of the sensor cable (40) and the network identification address of the leak detection system (S).8) The detection system (S) according to any one of the preceding claims, wherein said container (10) is made with IP67 degree of protection or higher.9) The detection system (S) according to any one of the preceding claims, wherein the sensing part (42) and the non-sensing part (41) of the sensor cable (40) are connected to each other by means of a silicone-coated soldering or by means of a two-pole connector (43), with IP67 protection or higher, resistant to temperatures from -40°C to +80°C.10) The detection system (S) according to any one of the preceding claims, wherein the non-sensing part (41) of the sensor cable (40) comprises the central portion (CC) of conductive material, made of a two-conductor cable and theelectrically insulating, impermeable outer protective sheath (Gl) made of a silicone sheath.11) The detection system (S) according to any one of the preceding claims, wherein the sensing part (42) of the sensor cable (40), resistant to temperatures from -40°C to +450°C, comprises the central portion (CC) of conductive material, made of two conductors individually coated with a sheath (G) made of liquid-permeable glass fiber, wherein the two conductors are interwoven with each other.12) The detection system (S) according to claim 11 , wherein the sensing part (42) of the sensor cable (40) comprises an insulation terminal (44) resistant to temperatures from -40°C to +450°C applied to the free end, in an opposite position with respect to the end connected to the non-sensing part (41).13) The detection system (S) according to any one of the preceding claims, wherein the sensor cable (40), if hit by water or water-based liquids, changes its resistance or conductivity, detecting an anomaly i.e. a loss of water-based liquids, wherein such anomaly is recognized by the detection device (20) as a variation in the resistance of the sensor cable (40) and signaled by means of the signaling elements (50, 52, 60).14) The detection system (S) according to any one of the preceding claims, wherein the central portion (CC) of the sensor cable is made of any conductive material selected from copper, aluminum, stainless steel, graphite and conductive alloys, and other conductive materials in general.15) The detection system (S) according to any one of the preceding claims, wherein the outer sheath (G) is made of a material selected from glass fiber, porous rubber, porous ceramics, fibrous materials and porous polymers, and other electrically insulating and liquid-permeable materials in general.16) The detection system (S) according to any one of the preceding claims, wherein, in the presence of an insulation (CO) on the element (E) to be monitored, the sensor cable (40) is positioned below the insulation (CO), i.e., in direct contact with the bare element (E) to be monitored.17) The detection system (S) according to any one of the preceding claims, wherein when the sensor cable (40) is worn, given its modularity, is replaced in a fast and simple manner.18) A method for detecting water-based leaks for an element (E) to be monitored in a plant includes using a sensor cable (40) to be positioned on said element (E) to be monitored, wherein said sensor cable (40) is configured to comprise a sensing part (42) comprising a central portion (CC) made of conductive material and an outer protective sheath (G) which is electrically insulating and permeable to water and to water-based liquids, wherein said method involves a step of receiving the signals generated by the sensor cable (40), a processing step for the signals and a deciding step performed based on calibration parameters and based on thresholds defined by the sensitivity set for the sensor cable (40), wherein said deciding step defines whether or not a leak has been detected by assessing a variation in the resistance of the sensor cable (40) due to the presence of waterbased liquids on said sensing part (42), and if so, the method involves a step of activating signaling elements (50, 52, 60) and communication elements (70) communicating with the control room and / or supervision systems for requesting maintenance on the monitored element (E).

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