METHOD FOR PROTECTION OF INNER CAVITY OF PIPELINE AGAINST CORROSION AND ABRASIVE WEAR Russian patent published in 2019 - IPC F16L58/10 F16L23/00 

FIELD: transportation.

SUBSTANCE: invention relates to pipeline transport. Method involves cleaning and drawing into the inner cavity of the polyethylene pipe. High-density polyethylene pipe with "shape memory" effect is used, with outer diameter making 2–3 % more than inner diameter of processed pipeline. First, pipe sections are welded, then pipe is drawn. Tube is preliminarily passed through crimping rolls with reduction of its diameter by 7–15 %. In order to temporarily stop pipeline restoration, clamping yokes are installed ahead of flange of treated pipeline section and polyethylene bushings are welded to pipe ends. For degassing of internal cavity of pipeline and annular space during installation of polyethylene pipe and prevention of its collapse in process of pipeline operation, ventilation standings are installed on it. Installation of pipeline sections is performed by connection of steel and polyethylene flanges by means of steel adjusting ring, and insulation of flange connection is performed by heat-shrinkage cuffs. Internal stresses of polyethylene pipe after installation are removed by thermal action of transported product.

EFFECT: method increases resistance of pipeline walls to corrosion, abrasive wear and accumulation of solid deposits.

1 cl, 2 dwg