System and blank for mfg. tubular half=shell and gutters

摘要

The tubular half-shells and gutter are of bent shape with any arbitrary arc radii for sewer drains. During mfr. a blank is used which consists of mutually slidable lamellae (2) orthogonal to the longitudinal axis of the tubular half-shells and gutters. Pref. the lamellae are interconnected by dovetail, movable joints (4). The lamellae may be conically tapered towards one end, thus forming a body of a conical shape to permit connection of pipelines of different dia. The lamellae may have circular, oval, or rectangular cross-sections.