The design of ring springs often involves complicated calculations and requires the consideration of multiple parameters.
As a method of obtaining the permissible stress, generally, the durability is evaluated from the tensile stress of the outer ring and the compressive stress of the inner ring.
Normally, it is recommended that the tensile stress of the outer ring be 1,100 N/mm² or less and the compressive stress of the inner ring be 1,300 N/mm² or less.