Introduction of outer dowty retarder

The dowty retarder, which was born in Harbin in the last century, is an important innovation of my country’s railway speed control equipment. However, this dowty retarder is installed on the inner side of the rail and is called the "inner dowty retarder". I encountered some troubles. The main reason was that the speed reducer had severely polished the wheel flange of the shunting locomotive, which was strongly opposed by the locomotive department. For this reason, the Shanghai Railway Bureau began to develop the outer speed dowty retarder, that is, the dowty retarder was installed on the outside of the rail.

There is no essential difference between the outer dowty retarder and the inner dowty retarderin terms of structural principles. It is also composed of three major components: cylinder, piston, and housing. The cylinder is equipped with hydraulic oil and nitrogen gas filled with a certain pressure, and it also works on hydraulic principles. Braking power, resistance power and critical speed are the three main technical indicators to measure its performance. The fundamental difference between the two is that the inner speed dowty retarder is installed on the inner side of the rail and contacts the wheel flange to do work. The outer dowty retarder is installed on the outside of the rail. The outer dowty retarder is installed on the outside of the rail.