HYDRAULAN® Brake Fluids
The brake system is one of the most important safety features of a vehicle and therefore needs to meet the very high standards required by the automotive manufacturers, the automotive industry and automotive safety legislation. Therefore brake fluids must meet stringent specifications and are often also officially approved by the automobile manufacturers.
Pioneering Brake System Safety
With the know-how of our chemists and technicians, BASF has been setting the market standard of brake fluids for more than 60 years. BASF was the first company to develop a low viscosity DOT 4 brake fluid, specifically for modern braking systems with electronic control systems such as ESP®/DSC, ABS and ASC. Together in partnership with both, automobile manufactures and OEM suppliers and as a member of the industry standards association we continue to develop and improve HYDRAULAN® brake fluids to meet both the current and future needs of the industry, and maintain the highest safety requirements demanded by customers.
BASF’s HYDRAULAN® brake fluids have been tested and proved in countless tests with OEM suppliers and automotive manufacturers to ensure optimum performance, reliability and compatibility with all of the components of the braking system.
ESP® = registered trademark of Daimler AG
1. Boiling Point
The absorption of water into the brake system from the environment can never be totally prevented. On average, the brake fluid in a vehicle absorbs up to 1,5 % water per annum. As the water content of the brake fluid increases the boiling point of the brake fluid decreases. During braking the heat of friction can heat the brake cylinders and the brake fluid to temperatures in excess of 150 °C. If the boiling point of the brake fluid is exceeded vapor bubbles form in the brake fluid, which, unlike liquids are compressible. When this happens a failure known as “vapor lock” occurs and the force applied to the pedal is not transmitted to the brake cylinders. Because of their high boiling points and chemical properties HYDRAULAN® brake fluids prevent the formation of bubbles and this potential failure of the brake system.
Braking takes place in fractions of a second. The hydraulic force generated through the actuation of the brake pedal needs to be transmitted to the wheel brakes instantly. Lower viscosity fluids transfer the force more readily than higher viscosity fluids and therefore it is essential that the brake fluid does not become too viscous at lower temperatures. HYDRAULAN® brake fluids have an extremely low viscosity, particularly at low temperatures and therefore give optimal brake responsiveness.
3. Corrosion Protection
Corrosion within the brakes system, leads directly to slower responsiveness, can cause blockages in the system or in the worst case lead to the integrity of the sealed brake system being broken. HYDRAULAN® contains highly effective additives which reliably protect the various metals in the braking system (e.g., steel, cast iron, aluminum, brass and copper) against both oxidation and corrosion.
Lubrication to prevent both friction and abrasion in the brakes system maintains responsiveness, reduces wear and prevents heat build-up in the brake system. By simulating braking under extreme conditions and by endurance testing of braking systems HYDRAULAN® has proved its excellent lubricating performance.
5. Elastomer Compatibility
Elastomer cups are used to seal the brake cylinders against loss of fluid in the gap between the piston and the cylinder. HYDRAULAN® has been specially formulated to allow for slight swelling of the elastomer cups to ensure a reliable seal and to prevent the loss of fluid.
6. High Temperature Thermal Stability
Under extreme operating conditions the brake fluid can reach temperatures in excess of 150 °C. Despite this high thermal loading the brake fluid must remain chemically and thermally stable. The use of high-quality glycol ester components and special inhibitors in HYDRAULAN® ensures maximum optimization of chemical and thermal stabilities.