Customize - Urban Dictionary Store

Pro Customization

Create unique products with your own words and definitions

Preview

Personalize Your Design

Your Word

Your Definition

A retarder is a device [used] to augment or replace some of the functions of primary friction-based braking systems, usually on heavy vehicles. [Retarders] serve to slow vehicles, or maintain a steady speed while traveling down a hill, and help prevent the vehicle from "[running away]" by accelerating [down the hill]. They are not usually capable of bringing vehicles to a standstill, as their effectiveness diminishes as vehicle speed lowers. They are usually used as an additional "assistance" to slow vehicles, with the final braking done by a conventional friction braking system. As the friction brake will be used less, [particularly] at higher speeds, their service life is increased, and since in those vehicles the brakes are air-actuated helps to conserve air pressure too.

Friction-based braking systems are susceptible to "brake fade" when used extensively for continuous periods, which can be dangerous if braking [performance] drops below what is required to stop the vehicle – for instance if a truck or bus is descending a long decline. For this reason, such heavy vehicles are frequently fitted with a supplementary system that is not friction-based.

Retarders are not restricted to road motor vehicles, but may also be used in railway systems. The British prototype Advanced Passenger Train (APT) used hydraulic retarders to allow the high-speed train to stop in the same distance as standard lower speed trains, as a pure friction-based system was not viable.

Text fits

Menu

Pro Customization

Preview

Personalize Your Design

Shopping Assistant