METHOD AND DEVICE FOR INNER CORROSION PROTECTION OF WELD JOINT ZONE Russian patent published in 2005 - IPC

FIELD: construction.

SUBSTANCE: device comprises the assembling-arresting unit which locks the bushing against self-unscrewing. The bushing is provided with a heat insulating material and sealing composition and is made of the self-unscrewing spring, which accumulates mechanical energy. The inner end of the spiral belt is provided with a blade, which is mounted in the vicinity of the face edge of the inner end of the belt and the ends of which are provided with guiding projections. The method comprises setting the assembling-locking unit with the bushing on the pipe end to be welded, assembling the pipe butt by moving the end of the pipe to be welded onto the projections of the bushing and heat insulating material to provide a gap between the pipe faces, unlocking the bushing, and removing the assembling-locking unit. The spiral belt is unwound with sliding with respect to the inner end. The gap size depends on the thickness of the assembling-locking unit. The projections of the blade cooperate with the side edges of the belt turns and cause the sealing composition to move thus providing a protecting roll.

EFFECT: enhanced reliability of the pipeline.

3 cl, 6 dwg