CAUSE FOR THE FORMATION OF GROOVES ON THE WHEELS OF BLOCK-BRAKED RAILROAD ROLLING STOCK AND THEIR PREVENTION

Grooves on the friction surface of block-braked car and locomotive wheels are not formed as a result of hard structural consitituents in the cast-iron brake blocks, but rather as a result of partial melting and displacement of the wheel steel softened by heating in excess of the solids temperature during the friction process. The displaced steel collects for the most part on the braking surface of the block in the form of foil laminations. The cause for this phenomenon lies in an excessively high softening temperature of the brake block material. To prevent the occurrence of this defect, it is suggested to use cast iron containing low-melting structural constituents in adequate quantity and distribution.