METHOD OF REPAIRING HIGH-PRESSURE MAIN GAS PIPELINE HAVING ISOLATION COATING DEFECTS (PIPE-CASING CONTACTS) LOCATED UNDER ROAD PAVEMENT AND CROSSING ROAD TRAFFIC WAY Russian patent published in 2004 - IPC

FIELD: building, particularly repairing underground pipelines.

SUBSTANCE: method involves digging out ground for opening access to pipeline casing and for investigating spatial location of pipeline relative casing by determining gaps between pipe and casing; defining more exactly relative spatial position of pipeline and casing after additional digging out ground around casing within the limits of 0.4 - 0.6 m from embankment foot of each road side by means of drilling 8 openings of 10 - 12 mm diameters spaced equal distances along pipeline perimeter and measuring gaps between pipeline and casing by probes; comparing refined data with previously obtained data; imparting mechanical action to pipeline; introducing building foam into gap between pipeline and casing through casing openings along with measuring electric potentials for determining absence of contact between pipeline and casing; additionally sealing gaps between pipeline and casing; backfilling area around pipeline with ground.

EFFECT: increased pipeline reliability.

2 cl, 4 dwg