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- VW Crack Meter - VWCM-4000
VW Crack Meter - VWCM-4000
Designed to measure movement across surface cracks and joints in a number of civil engineering and mining projects.
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They consist of a sensor outer body tube and an inner free-sliding rod which is connected at the internal end to a vibrating wire sensor by a spring. At the sensor end of the outer body and the external end of the rod anchors are attached which can be fixed either side of a crack to be monitored.
The gauge operates on the principle that a tensioned wire, when plucked, vibrates at its resonant frequency. The square of this frequency is proportional to the strain in the wire. Around the wire is a magnetic coil which when pulsed by a vibrating readout or data logger interface plucks the wire and measures the resultant resonant frequency of vibration.
Applications:
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Concrete structures |
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Stone & brick buildings |
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Dams |
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Tunnels |
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Construction joionts |
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Pipelines |
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Rock formations |
Features:
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Simple to install and read |
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High resolution & accuracy |
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Internal thermistor |
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Insensitive to long cable runs |
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Datalogger compatible |
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Ranges from 5 to 100mm |
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Waterproof up to 18 bar |
