METHOD OF PROTECTING CONCRETED PIPES WELDED JOINTS Russian patent published in 2025 - IPC F16L57/00 F16L13/00 

FIELD: construction pipelines.

SUBSTANCE: invention relates to construction and repair of pipelines with external concrete coating, laid on the bottom of a reservoir or on a swampy area. In the method of protecting the welded joints of concrete-coated pipes, a bushing which is preliminarily impregnated with a compound is installed on top of the welded joint and heat-affected zones of two pipe sections so that the edges of the end parts of the bushing form smooth cone-shaped transitions from the bushing to the end of the concrete shell of the pipes, and fluffed impregnated edges of the bushing closed parts are integrated into each other to form a seamless hollow cylinder around the pipe. Amount of hardener in the compound impregnating the bushing is set according to preliminary calculation so that the bushing material is polymerized after placing the pipe at the bottom. By means of tightening sleeves and coupling assembly the bushing is pressed to the pipe, ensuring tightness due to its reliable gluing with absolute obturation, which prevents ingress of electrolyte under the bushing and protects metal of the welded seam and heat-affected zone from corrosion. Pipeline section with welded seam is squeezed, thus making it thicker and stronger.

EFFECT: increased protection of the pipeline from external mechanical effects.

12 cl, 1 dwg