Purlin Systems

This means that design bending moments are distributed evenly along the building length, resulting in smaller section sizes and valuable economies achieved.

In the various possible arrangements of single and double span purlins, the Hi-Span sleeved system offers the customer low material costs, practical on-site advantages during erection, and excellent building performance thereafter.

Double Span Joint Arrangement. This system combines single and double span purlins with their joints staggered and sleeved. The provision of a sleeve at the unjointed connections over the penultimate support is required.

Single Span Joint Arrangement. Apart from the penultimate support this system has sleeves at alternate positions. Purlins must be continuous over a minimum of two spans using a sleeve, in order to create an end bay situation. (Sleeve arrangement as above, using single span purlins).

Heavy End Bay System

The Heavy End Bay System is the most recent purlin sytem to be made available from Hi-Span. A minimum of five equal bays is required for the system to perform economically with the use of heavier end bay sections. Sleeves are required at every purlin/rafter connection, no double span purlins. The system offers a very economical solution to the user in the long span multi-bay buildings, because considerable savings can be made in using lighter inner bay purlins, with the added advantage of simple erection procedure.

Single Span Joint Arrangement

End bay purlins and the penultimate sleeves are manufactured from heavier gauge material as shown.  Greater end bay moments are then accomodated by the larger section sizes, allowing lighter gauge sections to be designed for the inner bays.