Patent ID: 8991439
Filing Date: 2015-03-31
Classification: E03F,F16L

Abstract:
1. A metal pipe of single piece construction comprising: a wall formed of a single corrugated metal sheet, the sheet having opposing first and second edges extending longitudinally along the sheet, the wall including a seam formed by abutting portions of the first and second edges, the seam extending helically about and along a length of the wall, the sheet having an interior wall side and an opposing exterior wall side, the interior wall side defining an interior wall surface of the wall, the exterior wall side defining an exterior wall surface of the wall, the sheet having a cross-sectional profile defining 3 corrugation peaks at the exterior wall surface and 3 flat segments, each corrugation peak being separated by a respective one of the 3 flat segments and each flat segment being separated by an adjacent corrugation peak by an intervening sloped segment, the seam being located along one of the sloped segments, the wall defining a pipe diameter of at least 96 inches; wherein the sheet has a corrugation pitch of approximately 8 inches.