Monobloc Wheels and Tyred Wheels

Monobloc or tyred wheels are used as a function of the service conditions and stresses involved and the requirements of the railway enterprises, with new vehicles being fitted with tyred wheels only to a limited extent nowadays. Given the stresses and loads to which the wheel is subjected (forces between wheel and rail, temperatures as a result of block braking, centrifugal forces, etc.) and the requirements ensuing from technical codes, specifications, weight management, acoustics, etc., it is necessary to have various wheel designs, especially for the web. Examples in this regard include stress-balanced, vibration-optimised, tangential-corrugated and arched shapes. Where tyred wheels are concerned, the wheel centre is additionally subjected to high stresses through the shrink-fit connection between the tyre and the monobloc wheel body. Special designs (double-, tangential-or single-corrugated, etc.) are hence used for this purpose, too. The shrink-fit stresses additionally make it necessary to optimise the materials used for the monobloc wheel body in order to avoid impermissible deformations.