When choosing a Solon brand Belleville spring washer considerations should be: ID, OD, application, environment, temperature, washer material, load, bolt size, bolt material and stacking constraints. Reasons why a bolted joint may fail are often due to bolt yield, bolt creep, differential thermal expansion (DTE), embedment relaxation, vibration and loosening of the connection between the bolt and nut. When an external force is applied, the compressive strain is distributed among all assembly parts and connections, which reduces the fatigue and retains the integrity of the bolted joint. Contact us for an engineered solution to your custom specifications and unique application requirements. Made in USA.