DEVICE FOR CLEANING INNER SURFACE OF TUBING STRING (VERSIONS) Russian patent published in 2010 - IPC E21B37/02 

FIELD: oil and gas industry.

SUBSTANCE: as per the first version, the device includes the extended housing being a weighting material, scrapers installed on the housing and which are identical and arranged on common rod, attachment assembly to the traction element, a fairing. Each scraper includes not less than two identical radial knives made in the form of right-angular trapezoid the lateral sides of which are working and have double-sided sharpening. Radial knives are rigidly fixed with their large bases of trapezoids on the side surface of the rod, parallel to its longitudinal axial line, at equal distance from each other and at an angle of 90° to its surface. In smaller base of the trapezoid there rigidly fixed is a cutter made in the form of a plate with double-sided sharpening in the form of ellipse, one of axes of which coincides with smaller trapezoid base. Scrapers are turned on the rod relative to each other so that in the space the cutters of upper scraper cutters of lower scraper. Lower end of the rod is rigidly fixed on upper end of the housing, and its upper end is attached to attachment assembly to traction member. Vertical axial lines of the housing, rod and assembly coincide.

EFFECT: improving the cleaning quality.

21 cl, 29 dwg