Trough, manufacturing process, and apparatus

Abstract

The disclosure concerns a smooth continuous steel trough, free of longitudinal weld joints except for a flanged frame attached to its open top for supporting a cover grating. The apparatus for performing these steps comprises a conveyor table for moving and clamping a parallel edged sheet of steel while it is cut, such as by a torch, to predetermined length sides, and angled ends corresponding to the flow pitch for the resulting trough. The resulting isosceles trapezoidal section is then conveyed and aligned under an oscillatable convex mandrel or roller having a longitudinal clamping rib axially along its periphery for clamping the trapezoidal sheet near its center at the bottom of what is to be one of the equal side walls of the resulting trough. The conveyor and/or support for the sheet at the mandrel is vertically adjustable to compensate for different size mandrels and thicknesses of the sheets. Separate spaced manually-driven frictional rollers or tired wheels are hydraulically engageable to raise the plate and support it while under the mandrel, which wheels can be separately manually rotated for aligning the trapezoidal sheet with the mandrel before its longitudinal rib clamps the sheet against the supporting table. The free unclamped longer end of the sheet is then wrapped around the mandrel by a freely rotatable roller revolvable on adjustable parallel arms. The resulting sections are then placed in a rack or jig with their equal adjacent sides aligned for welding into a sub-assembly.