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.
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.
by Huvudpersson July 24, 2017
The stench that one leaves behind after he or she fails to convince a small group or a large audience that they aren't required to wear a helmet on a regular basis outside of the skatepark and bike trails and that their parents weren't lovers and siblings.
Mary and Tony went to the store to pick up some cereal when they saw a man standing in front of the bananas and he was scratching his ass and making monkey sounds, "What was wrong with that man?" Mary questioned.
"I can't be certain but it seems to me as though this man had a certain odour to him, clearly he's a simple fuckface who chews on old tampons and desperately Reeks of retard."
"I can't be certain but it seems to me as though this man had a certain odour to him, clearly he's a simple fuckface who chews on old tampons and desperately Reeks of retard."
by FingerbangbangbangGangbang13 November 02, 2020
Spontaneous Retard Disorder or SRD affects 1 in 3 people, most being white woman. When faced in situations where they are in the wrong ,SRD symptoms have a 95% percent chance arising. The symptoms are equivalent to a 3 year old baby having tantrum. The symptoms include Intense swearing, physical violence , emotional turmoil and in some severe cases psychosis. There is no known cure to SRD. Therapy is the only known way to lessen the effects. If you know someone with SRD try to communicate in a way which doesn't arise affects and helps them calm down. It currently affects roughly 125 million people.
Jessica started screaming and crying. When I went to try and calm her down she started attacking me for no reason calling all sorts of foul things. I didn't realize she had Spontaneous Retard Disorder and since forgiven her.
by Kakwkwk April 22, 2022
A locked psychiatric unit or facility that people with a mental illness and/or mental disability are incarcerated for wrong doing.
by 6sharpie9 December 08, 2015
by karazan145 December 18, 2021
Get the retard salad mug.