ROOF CRUSH 6 .
Remedies cont:
Manufacturers have used a variety of techniques to strengthen roof supports for adequate protection in rollovers. The Fiat and Porsche convertibles illustrate a common approach for convertibles -tubular elements the "A" pillar. The Mercedes sectional drawing of the roof rail (above the doors) illustrates another "sectional" design approach. This design provides a stiffer, stronger component by boxing in the roof header and probably by using thicker sheetmetal. Many domestic and Asian brands have open sections with holes punched in the roof header and "A" pillar, a cheaper, weaker design.
Recently, some manufacturers have started to introduce ultra high strength steels, generally "boron steel" in the roof and support structures. But the new materials are not really necessary as the old Volvo ad on the right shows.
.
Porsche with " A" pillar reinforcement.