DEVICE FOR INTERNAL SURFACE CLEANING OF TUBING (VERSIONS) Russian patent published in 2015 - IPC E21B37/02 

FIELD: oil and gas industry.

SUBSTANCE: device contains (for all versions) elongated casing 1, that simultaneously is weighting material, and scrapers 2, 3 secured at its ends. Each scraper 2, 3 contains bar 6 (16) and secured by pairs, identical radial knives from first 7 to forth 10 in form of isosceles trapezoid, its sides are work, and gave two-side sharpening. The cutters 11-14 are connected with each other at small bases of the trapezoids with creation of the cutting angle and spike. The first cutter 11 connects the smaller bases of the trapezoids of the first 7 and forth 10 radial knives, the second cutter 12 - of the forth 10 and second 8 knives, the third cutter 13 - of the second 8 and third 9 (not shown) knives, the forth cutter 14 - of the third 9 and first 7 radial knives. The cutting angles are from 36 to 86°. Under the second option the scrapers 2, 3 are made with possibility of rotation.

EFFECT: increased quality of cleaning by reduced area of contact of the scraper with deposits, improved cutting conditions, reduced probability of emergencies.

3 cl, 9 dwg