Purlins

Process

Rollco was asked to create a light weight roof structure for the Dunc Gray Velodrome, a venue used at the Sydney 2000 Olympics. In response to the unusual architectural and engineering requirements, research and development was undertaken to establish procedures and tooling to enable curving of Cee purlins.
Since that time, many structures have been constructed incorporating Cee purlins, achieving cost effective gains by minimizing weight and connection details. This is carried out through a cold rolling process and curving can only be done through the X-X Axis, due to the thinness of the section.
 

Lead in / out

Lead in / out is a term used to describe the amount of material required before and after the curves necessary for "grab" in the machine. This material remains straight and needs to be removed after rolling. Due to the properties of purlins, twisting is inherent when curving. To minimize this effect an additional 1100 mm on each end is required for lead in / out.
 
 
Capacity

As a general rule, the heavier section should be specified, as this enables tighter radii and the integrity of the section to be maintained.
C100 purlins are possible to roll, although we have not manufactured tooling for this size due to its unpopularity. The following table is intended as a guide only and we encourage enquires for more specific details, as individual specifications may require alternative designs.
 

Section          Minimum radius

C15024         8000 mm
C20024         35000 mm
C25024         75000 mm