If you are designing or constructing roll cages, you need to be sure that the materials used to create them will offer ultimate protection in the event that they are needed.
Initially, roll over protection was brought in to protect farmers driving tractors. Since the 1920s, deaths from tractor roll-overs have been reported across the world, and in 1959, Sweden enacted a law which required all newly-built tractors to comply with roll-over protection structure (ROPS) regulations.
In 1967, the USA followed suit and developed guidelines for roll-over protection, and in 1975 the legislation was passed to ensure that all tractors would be compliant with ROPS regulations.
Nowadays, roll cages are used across a range of motorsports and aerospace industries to provide structural integrity and protect lives.
There are a number of different options to consider when constructing roll cages. It is important that the material possesses the necessary structural qualities and meets legal compliance. The most popular metals are T45 and CDS, which are both accepted by the authorities as recognised roll cage appropriate.
T45 is a significantly stronger metal than CDS. T45’s tensile strength is two-thirds higher than CDS, and the minimum yield strength is nearly double that of CDS.
This significantly higher strength means that roll cages using T45 can achieve the same protection as CDS, whilst operating effectively with a thinner wall tube. This saves on weight – something that is an essential consideration for those in motorsport.
Whilst this is highly beneficial, T45 also comes at a higher price as a result. For those looking solely to reduce cost, CDS may be the way to go, but for many, T45 roll cage tube is worth the investment.
There are also variations in the installation techniques of roll cages. Some roll cages are ‘bolt-in’ and some are ‘weld-in’. Welding is recognised as the most solid approach, and is employed by most professional motorsport teams.
Although the roll cages that are currently on the market are highly effective at protecting drivers and passengers, the technology is always developing and safety standards are always improving.
From an aesthetics perspective, recent years have seen increasingly subtle roll cages introduced as standard, and in some vehicles, an in-vehicle system will deploy an extendable roll cage when it senses that a roll-over is in process.