The present invention relates to a surface cover for a body which can be brought into contact with a liquid, comprising: a layer which at least partly contains gas and which is designed and arranged such that at least some sections of a layer face facing the liquid contacts the liquid; a gas-permeable layer which is arranged on the gas-containing layer on a face that faces the body and is opposite the face facing the liquid or which is integrally formed with the gas-containing layer; and a gas-supplying device which is connected to the gas-permeable layer such that gas can flow from the gas-supplying device to the gas-containing layer through the gas-permeable layer. The invention also relates to an arrangement and a use.

The present invention relates to a surface cover for a body which can be brought into contact with a liquid, comprising: a layer which at least partly contains gas and which is designed and arranged such that at least some sections of a layer face facing the liquid contacts the liquid; a gas-permeable layer which is arranged on the gas-containing layer on a face that faces the body and is opposite the face facing the liquid or which is integrally formed with the gas-containing layer; and a gas-supplying device which is connected to the gas-permeable layer such that gas can flow from the gas-supplying device to the gas-containing layer through the gas-permeable layer. The invention also relates to an arrangement and a use.

The method and system uses ultrasound (US) transducers in contact with an inboard surface underwater portions of marine vessels or structures. By first digitally generating disruptive, multi-frequency, interfering US waveform signals (complex waveforms, typically replicating a Bessel function) and then converting the signals into analog, the transducers generate disruptive, multi-frequency, interfering US waveforms through the underwater portions of the marine vessels and structures which waveforms disrupt unwanted marine growth on the water-side of the vessel or structure. The digital signals, and also the analog signals, are complex waveform signals, typically produced with a Bessel function. The US transducers are either circular membrane transducers or surface transducers. A computer processor coupled to a memory, generates the complex waveform signals fed to the US transducers.

The method and system uses ultrasound (US) transducers in contact with an inboard surface underwater portions of marine vessels or structures. By first digitally generating disruptive, multi-frequency, interfering US waveform signals (complex waveforms, typically replicating a Bessel function) and then converting the signals into analog, the transducers generate disruptive, multi-frequency, interfering US waveforms through the underwater portions of the marine vessels and structures which waveforms disrupt unwanted marine growth on the water-side of the vessel or structure. The digital signals, and also the analog signals, are complex waveform signals, typically produced with a Bessel function. The US transducers are either circular membrane transducers or surface transducers. A computer processor coupled to a memory, generates the complex waveform signals fed to the US transducers.

An antifouling layer stack comprising a first layer element, a silicone layer, and a second layer element. The silicone layer is a light guide for UV radiation, and may include embedded UV light sources. The first layer element is situated on a first surface of the silicone layer, and the second layer element is situated on a second surface of the silicone layer. The first and second layer elements differ in composition from the silicone layer. The first layer element facilitates transmission of the UV radiation from the silicone layer to an external medium, and may provide protection and improve the structural integrity of the stack. The second layer element may also provide protection and structural integrity. The second layer element may be reflective, and may provide an adhesive surface for attaching the stack to a vessel.

An antifouling layer stack comprising a first layer element, a silicone layer, and a second layer element. The silicone layer is a light guide for UV radiation, and may include embedded UV light sources. The first layer element is situated on a first surface of the silicone layer, and the second layer element is situated on a second surface of the silicone layer. The first and second layer elements differ in composition from the silicone layer. The first layer element facilitates transmission of the UV radiation from the silicone layer to an external medium, and may provide protection and improve the structural integrity of the stack. The second layer element may also provide protection and structural integrity. The second layer element may be reflective, and may provide an adhesive surface for attaching the stack to a vessel.

A marine ICCP system includes an electrical circuit comprising a primary and a secondary circuit. The primary circuit comprises a first electrode connected to a positive terminal of a power source to act as an active anode; and a second electrode connected to a negative terminal of the power source. The secondary circuit comprises a passive electrode normally disconnected from the electrical circuit and arranged to act as back-up protection, wherein the second electrode connectable to the passive electrode. The passive electrode is arranged to be connected to the power source if a detected output voltage in the primary circuit reaches a maximum value and if a determined polarization potential for the cathode is insufficient. The control unit is operable to control the output voltage supplied to the primary and secondary circuits separately in order to supply an individual output voltage to each circuit.

A marine ICCP system includes an electrical circuit comprising a primary and a secondary circuit. The primary circuit comprises a first electrode connected to a positive terminal of a power source to act as an active anode; and a second electrode connected to a negative terminal of the power source. The secondary circuit comprises a passive electrode normally disconnected from the electrical circuit and arranged to act as back-up protection, wherein the second electrode connectable to the passive electrode. The passive electrode is arranged to be connected to the power source if a detected output voltage in the primary circuit reaches a maximum value and if a determined polarization potential for the cathode is insufficient. The control unit is operable to control the output voltage supplied to the primary and secondary circuits separately in order to supply an individual output voltage to each circuit.

The invention relates to an arrangement for measuring salinity in water, which arrangement is part of an impressed current cathodic protection system having an electrical circuit comprising a source of electrical power (310); at least one first electrode (315) connected to a positive pole of the power source (310); at least one second electrode (317) connected to a negative pole of the power source (310); a voltage sensor (341); a current sensor (342); and a control unit (313). The control unit is arranged to initiate a measurement sequence at predetermined intervals, wherein the control unit is arranged to connect at least one first electrode (315) to the negative pole of the power source (310) to act as a cathode; connect at least one passive electrode (326) to the positive pole of the power source (310) to act as an active anode; register the output voltage; register the current; determine the circuit resistance using the output voltage and the current; and calculate the resistivity of the electrolyte based on the determined circuit resistance and at least one stored electrode property value, which resistivity is inversely proportional to the salinity. The invention further relates to a vessel provided with such a measuring arrangement and a method for its operation.

The invention relates to an arrangement for measuring salinity in water, which arrangement is part of an impressed current cathodic protection system having an electrical circuit comprising a source of electrical power (310); at least one first electrode (315) connected to a positive pole of the power source (310); at least one second electrode (317) connected to a negative pole of the power source (310); a voltage sensor (341); a current sensor (342); and a control unit (313). The control unit is arranged to initiate a measurement sequence at predetermined intervals, wherein the control unit is arranged to connect at least one first electrode (315) to the negative pole of the power source (310) to act as a cathode; connect at least one passive electrode (326) to the positive pole of the power source (310) to act as an active anode; register the output voltage; register the current; determine the circuit resistance using the output voltage and the current; and calculate the resistivity of the electrolyte based on the determined circuit resistance and at least one stored electrode property value, which resistivity is inversely proportional to the salinity. The invention further relates to a vessel provided with such a measuring arrangement and a method for its operation.