Machine and process for forming tapered or cylindrical utility poles from flat sheet metal

摘要

A method and apparatus for producing tapered, cylindrical poles from trapezoidal metal strips. The process is comprised of the steps of curling or pre-forming a trapezoidal blank, then forming the pre-formed blank into a tubular shape by means of a shovel die. The tubular shaped blank is then welded along a longitudinal seam such that a tubular pipe is formed. The resulting tapered cylindrical poles are typically used around highways, parking lots and playing fields to support lights or signs. The process can also be used to form thin wall cylindrical pipes.