METHOD OF MEASURING DEFORMATION AND APPARATUS FOR REALISING SAID METHOD Russian patent published in 2012 - IPC G01L1/12 G01B7/16 G01N27/72 

FIELD: physics.

SUBSTANCE: measuring element is magnetised to saturated state. Multiple loading and unloading of the measuring element is alternated until achieving maximum measured deformation. The inner areas of the middle part of the measuring element undergo local multidirectional magnetisation. Deformation is measured using a magnetic field sensor. The deformation value is determined based on the value of the stray magnetic field of the measuring element near the ends of a magnetic insert and the calibration curve of deformation ε versus H_mak. After a given time interval, deformation measurement is repeated inside the measuring element while first carrying out local multidirectional magnetisation of the inner middle part. Based on the value of magnetic field strength near the ends of the measuring element and the calibration curve of deformation (ε) versus stray magnetic field strength (H), the deformation value of the measuring element is determined, and the maximum deformation value, existing after local multidirectional magnetisation, is determined from change in the value of the magnetic field of the locally multidirectionally magnetised inner areas of the middle part of the measuring element and the calibration curve of deformation ε=f(ΔH). The apparatus has a magnetising device in form of coils, a ferroprobe, a measuring element which is hollow and adapted to accommodate magnetising coils or the ferroprobe. The apparatus further comprises a measuring line which includes at least one measuring element made from a magnetic insert, and nonmagnetic inserts fixed on supports by fastening elements. The magnetic inserts are made from ferromagnetic material, having magnetoelastic hysteresis and piezomagnetic effect, and the magnetising coils lie coaxially and are spaced apart.

EFFECT: high accuracy of measuring deformation both in peak load memory mode in a given time interval and in analogue mode at any moment in time; possibility of measuring deformation of objects.

3 cl, 2 dwg