What is Dever? : In order to reduce the centrifugal force that wants to swing the vehicles going at certain speed in the curves to zero, in other words, to make the tilting moment zero, the outer rail should be removed slightly to bring the combination of the centrifugal force and the weight of the wagon as the mass of the wagon to the plane passing over the rail and to the middle of the road opening. . Here, in order to meet the centrifugal forces and to make them harmless, the horizontal curves are called a demagnetisation of the outer rail array in a certain amount compared to the inner rail array. Dever is proportional to the velocity, inversely proportional to the radius. In other words, the speed increases as the speed increases. The radius becomes smaller as the radius grows. Dever is divided into three according to account and its application. Dever is divided into three according to account and its application. Theoretical dever, normal (ideal) dever and minimum dever.