METHOD OF EXAMINATION OF DEPOSITS FORMED ON WALLS OF WELL FLOW STRING AND DEVICE FOR METHOD EMBODIMENT Russian patent published in 2003 - IPC

FIELD: well research; designed for determination of longitudinal profile and physico-chemical properties of heavy hydrocarbon and salt deposits on walls along flow string, and also for rock sampling from walls of uncased well. SUBSTANCE: method includes lowering on rope of multisectional sampling device into well flow string filled with fluid; sectional sampling of solid deposits from flow string walls in at least three points uniformly spaced over internal circumference of flow string. Operation of each section over well depth is accomplished alternately at corresponding values of fluid column hydrostatic pressure or by building up of required excessive pressure at wellhead. Then, taken samples are subjected to measurement of their thickness and physico-chemical analysis at surface. Device for method embodiment has rope suspension unit, body with radial cylinders accommodating sampling bushing capable of radial extension, and hydromechanical power mechanism for bushing extension. Device is provided with several successively connected autonomous sections, each of which has in body three radial cylinders located at angle of 120 deg.on same horizontal plane and accommodating sampling bushings in form of stepped sleeves with spherical stops, side bypassing longitudinal channels and toothed cut made on internal surface, two branch pipes connected to body from atop and from below whose cylindrical chambers accommodate hydromechanical power mechanism isolated from fluid medium by diaphragm rated for preset rupture pressure and installed in upper branch pipe, under its side holes hydraulically communicating diaphragm with well fluid. EFFECT: higher efficiency and simplification of process of examination of well flow string for quantitative and qualitative evaluation of formed solid deposits on its walls. 3 cl, 2 dwg