ABSTRACT
Cylindrical Elastomagnetic Gauge A Cylindrical gauge takes the form of a hollow cylinder in the middle of which the measured element (bar, wire, strand ) passes through. It must be slipped onto the measured element beforehand, during the construction. This type of gauge consists of primary, secondary and compensating windings, mounted in a protective steel shield and sealed with an insulating material. The time dependence of magnetic flux through the measured element, produced by a DC and AC current in the primary winding, induces a voltage in the secondary winding. The influence of the measured element radial displacement, which is essential to reduce the error when measurements are made using cables, is allowed for by the voltage induced in a compensating winding. This cylindrical elastomagnetic gauge has no mechanical contact with the measured element so therefore can not be overloaded, is resistant to water and mechanical damage, its characteristics does not change with time and its lifetime is serviceably unlimited (i.e. more than 50 years). These elastomagnetic gauges enable stress measurements in strands and cables protected by steel or PE tube without requiring removal. The gauge is connected to the measuring system through a cable whose length can be up to 500 m The parameters of a selection of cylindrical gauges for ~asuring force or stress in steel rods, wires and cables with cross section up to 1 0000 mm used to date are shown in Table 1.
