One way locking dowty retarder

When the locomotive or vehicle reversely passes through the dowty retarder, the sliding cylinder will be locked in the low position after being pressed down by the wheel flange, and will not brake the vehicle. Therefore, reverse traction can not limit speed.

The sliding cylinder is equipped with a return valve which can adjust the return speed of the dowty retarder. For different grades of dowty retarder, there are different forward return speeds. Among them, the positive return speed of 0-I gear dowty retarder is slow. The Zang speeder can not only brake the rolling vehicles passing through it at a slower speed, but also have little or no braking effect on the high-speed vehicles pulled out in the positive direction. On the other hand, the forward return speed is fast, which means that when the vehicles are sliding through the dowty retarder at a high speed, the retarder will do full work for each round.