METHOD OF DEFECTOSCOPY OF WELL PUMP RODS Russian patent published in 1995 - IPC

FIELD: defectoscopy. SUBSTANCE: stresses are created in the body of the rod which excess over stresses in it during exploitation. The rod is subjected to volumetric-contact dressing and loading of the rod is changed from value of minimal to value of maximal and then to value of minimal loading of the rod inside well. The rod is magnetized longitudinal simultaneously with changing load till saturation and level of output signal is measured. Then the rod is loaded step by step with following removal of the load after each loading. Such a loading has to be continued at non-proportional elongation of the rod depending on change in load but no more than limit of strength of material of the rod. After that the rod is repeatedly loaded and magnetized and level of output signal is measured again. Capability of the subsequent exploitation of the rod is judged from the comparison of results of measurements. EFFECT: improved truth of determination. 2 cl