Technical Information
Man-Entry Applications
The Danby system, which is used in a variety of man-entry applications, is simply ribbed plastic panels which are placed inside a pipe and locked together on the edges to form a continuous liner. The PVC panels incorporate male and corresponding female double locking edges. The edges form a circumferential joint which is simply snapped together by a smaller joiner strip. The joiner strip utilizes a flexible polymer co-extrusion to make the joint gas and water tight. Both the panels and joiner strips are manufactured from rigid PVC. Danby is extruded in 300 mm (12in.) widths with an overall profile thickness of 12.5 mm, 17.5mm and 25mm. The panels and joiner strip are light and easily handled and can be passed through a narrow opening or manhole; therefore, there is no need for excavation. Installation is quick and simple.
In 360º lining applications, Danby is normally supplied to the job site in 50 metre coils. In these applications, Danby is spirally wound into a liner from the coils of PVC strip. In partial lining applications, the panels are delivered to the job site in specified pre-cut lengths from the factory. The panels incorporate outer ribs and the inside surface is smooth. The ribs, when curved to the contours of the pipe, impart a hoop strength which supports the liner in place. Another feature of these ribs is that they provide a mechanical anchor for the PVC liner as the annular gap is filled with suitable grouts. In man-entry pipes, practically all of the annulus can be expected to be filled by the grout and almost any type of grout can be used. This allows greater freedom of design to address structural problems, including the possibility of adding steel reinforcing rods or wire mesh. Danby has been successfully installed in a variety of applications including circular (360º), circular partial lining (270º, 240º, etc.), oval, and egg-shaped lines, as well as box structures, manholes, and wet wells.