Advances in Fluorosilicone Compounds for Turbocharger Hose Liners and other Transportation Applications
|Date Published||January 1, 2006|
Turbocharger hose use has undergone significant growth in recent years. In the US, turbocharged engines are increasing in heavy duty pick-ups and have been in common use for large (e.g. Class 8) tractor trailer vehicles. In Europe, the growth of turbodiesel engines for passenger cars has resulted in increasing demands of the materials used in these system components. Flexible hose sections are being challenged to perform in harsh environments. Increasing temperatures and pressures are required in service. Barrier properties of hot exhaust containing aggressive petrochemicals and other combustion by-products are necessary. The typical construction for turbocharger hoses utilizes VMQ silicone with a fluoroelastomer liner (FVMQ fluorosilicone or FKM fluorocarbon). To contain the pressure and vibration at temperature, multiple layers of a high temperature fabric (e.g. aramid) are part of the overall reinforced hose assembly. Significant progress has been made to address the increasing demands on fluorosilicone rubber compounds used in turbocharger hoses. Aggressive hot oil resistance, higher service temperatures, compound economies, and improved adhesion to VMQ silicone are some of the areas that will be presented. The development and data presented is centered on turbocharger hose and similar under hood applications. These findings, however, can be used as technical enablers for a wider understanding of the flexibility and performance of fluorosilicone use for other oil, solvent, and fuel resistant opportunities.