Eddy-current sensor

Abstract: A multifunctional sealing testing device of cavitation and visualization includes a testing bench, a drive device, a loading device, a testing device and a controller. A plurality of columns are installed on the testing bench; an upper bracket and a lower bracket are respectively fixed between the columns; the drive device comprises a drive motor, a spindle box, a spindle, a synchronous belt wheel and a synchronous belt; one end of the spindle is connected with a moving ring of the loading device; the loading device comprises a moving ring, a static ring, a static ring seat, a spring seat, a spring, an upper pressing plate, a lower pressing plate and a screw rod; the testing device comprises an upper positioning piece, a lower positioning piece, an electric eddy current sensor, a metal dowel steel, and a side pressure sensor; and the drive motor, the electric eddy current sensor, and the side pressure sensor are connected with the controller. The beneficial effects of the utility model are: the cavitation phenomenon of the lubricating film can be visually observed; various sealing performance parameters can be accurately and comprehensively tested; the compression rate of the spring can be conveniently adjusted; and the multifunctional sealing testing device of the cavitation and the visualization can also be used for the friction and abrasion test between ring-ring test pieces.

Abstract: The invention discloses an indexing accuracy measuring device, which comprises a detected mechanism and a detection mechanism, wherein the detected mechanism is fixedly arranged on an indexing mechanism and comprises a detected block support and a metallic detected block, wherein the metallic detected block is fixedly arranged on the detected block support; and the detection mechanism comprises an eddy current sensor probe, a sensor support and a detection circuit, wherein the eddy current sensor probe is fixedly on the sensor support and is placed adjacent to the metallic detected block, and the eddy current sensor probe is connected with the detection circuit and is used for measuring the distance between the eddy current sensor probe and the metallic detected block The indexing accuracy measuring device is designed aiming at detecting the indexing accuracy of an indexing device By changing the design of the detected block support, the accuracy is guaranteed and the indexing accuracy of the indexing device can be conveniently and directly detected at the same time

Abstract: PROBLEM TO BE SOLVED: To provide a simply-structured vortex sensor capable of stably detecting a film thickness of a conductive film with high sensitivity without being affected by a material of a surrounding structure in which an eddy current sensor is disposed, and the eddy current sensor. SOLUTION: The eddy current sensor includes sensor coils disposed near a substrate on which the conductive film has been formed, induces an eddy current to the conductive film by turning on alternate currents to the sensor coils, and measures the film thickness of the conductive film by detecting a change of magnetic flux resulting from the eddy current by induced voltages induced to the sensor coils. The sensor coils 21, 22, and 23, and the sensor coils 21, 22 and 23 are disposed on a sensor head 24 and composed of a pair of A-side and B-side coils, respectively. When each coil of the pair of coils is turned on, a current Ia flowing around one coil of the sensor head 24 has the same absolute value as a current Ib flowing around the other coil and flows in an opposite direction. COPYRIGHT: (C)2011,JPO&INPIT

Abstract: Regular high-strength carbon steel is currently the most commonly used pipe material for onshore and offshore pipelines. The corrosion of offshore pipelines is a major problem as they age. The collapse of these structures as a result of corrosion may have a heavy cost is lives and assets. Therefore, their monitoring and screening is a high priority for maintenance, which may ensure the integrity and safety of a structure. Monitoring rises and subsea pipelines effectively can be accomplished using eddy current inspection to detect the average remaining wall thickness of corroded low-alloy carbon steel pipelines through corrosion scaling, paint, coating, and concrete. A test specimen for simulating the offshore pipeline is prepared as a standard specimen for an analysis and experiment with differential bobbin eddy current sensors. Using encircling coils, the signals for the defect in the simulated specimen are analyzed and evaluated in experiments. Differential bobbin eddy current sensors can diagnose the defects in a specimen, and experiments have been carried out using the developed bobbin eddy current sensor. As a result, the most optimum coil parameters were selected for designing differential bobbin eddy current sensors.