SPIRAL PIPE FOR MIDDLE AND LARGE DRAIN PIPE LAID UNDER THE GROUND IN THE COURSE OF ROAD CONSTRUCTION

摘要

PURPOSE: A spiral pipe for a middle or large drain pipe in the course of road construction is provided to resist the earth pressure by integrally forming the middle wall at both side walls in the hollow and the supporting wall in the inner hollow, and by bending the outer wall and fixing with the bonding point. CONSTITUTION: A hollow is formed by an inner wall(25), an outer wall(31) and both side walls(24), and a spiral pipe(20) for a large or middle drain pipe is manufactured by integrally forming a bonding bar(48) at both side walls. An inner hollow port(29) and an outer hollow port(30) are formed by protruding a middle wall(36) at both side walls, and bent parts are formed intermittently by winding the outer wall spirally. Bonding points(34) are integrally formed in the middle wall, and the supporting wall is protruded from the inner wall and the middle wall in the inner hollow port.