The current trend in car engines is toward ‘downsizing’ in order to reduce fuel consumption and ecological impact. This means that engines are becoming smaller and lighter – but without sacrificing power output. Often, a turbocharger is fitted onto a small displacement volume engine. Generally speaking, a downsized engine means increased operating temperatures for hoses, as power is generated in a smaller space and parts are placed closer together and constructed as lightly and compactly as possible.
At the same time, car ownership and production is rapidly growing in emerging economies. And even locally built cars must increasingly meet global benchmarks on safety, reliability, fuel economy and service life.
Car buyers expect all automotive rubber hoses to have the same life expectancy as the vehicle itself. This means a safe and reliable vehicle – without breakdowns in unexpected and/or hazardous places and no additional costs for maintenance and repairs. As a result, various types of automotive hoses face a wide range of exacting demands:
- Radiator hoses need to be resistant to the chemicals in cooling liquid – even at elevated temperatures – and need to withstand pulse pressure and vibration
- Turbo hoses need to function despite operating temperature and pressure increases from generation to generation
- Fuel hoses need to withstand new fuels like bio-diesel or bio-alcohol
What are the benefits of using aramid?
Twaron, Technora and Teijinconex aramids are already used extensively in automotive hoses – and we are constantly discovering new applications for them. Compared to traditional hose reinforcements, their advantages are:
- High strength at low weight: Because Twaron and Technora are so strong, smaller amounts of material are required to reinforce hoses.
- Chemical resistance: Radiator and transmission-oil coolant hoses are particularly exposed to chemicals at high temperatures. Twaron and Technora are highly chemically resistant and so suffer very little degradation from processes such as hydrolysis.
- Temperature resistance: Technora – and Teijinconex in particular – have long-term resistance to the high temperatures found, for example, in turbo charger hoses.
- Dimensional stability: Twaron and Technora are thermosets with very low thermal expansion and creep. Even after prolonged stress at elevated temperatures, Twaron and Technora keep their original shape.