method and apparatus for underground and partially submerged pipe lining

摘要

method and apparatus for submerged and partially submerged pipe lining. An apparatus and method for coating an underground conduit is described. apparatus (10) comprises: an annular structure (40) with a crown part (42) and a base part (49); a strip guide disposed around and supported by the annular structure (40), the guide arranged to guide a strip (12) around a helical path; a pair of strip pull rollers mounted on the frame (40) in a circumferential position about halfway between the crown part (42) and the base part (49); a frame-mounted drive assembly for bringing the strip (12) down to the helical path in a sheath direction to provide a first edge leading to an adjacent second edge of a strip coated convolution; a frame-mounted liquid remover, the liquid remover arranged to prevent liquid adhering to and rising from the second edge from reaching the first incoming edge; and an extruder (80) mounted to the frame (40) for extruding a molten plastic fillet onto the strip (12) in a position just prior to said overlap.