Screeching of rail cars on curves is caused by lateral sliding of the wheels connected with stick-slip. Vibrations of the wheels are excited. The stick-slip-effect is based on the existence of different coefficients of static and dynamic friction. The approximation of the two coefficients of friction by a chemical surface treatment of the tread of rail should suppress stick-slip and screeching. The influence of phosphate and oxalate coatings on stick-slip is investigated. These coatings nearly entirely suppress stick-slip of steel surfaces sliding one against the other (Delta my = 0,003) but wet phosphate coatings are quickly destroyed by wear in contrast to wet oxalate coatings which are stable. For screening tests in laboratory several tribometers are used. Practical tests are carried out at the subway in Berlin. Fluids containing oxalic acid as the main component beside other compounds were developed which suppress screeching of the cars on curves successfully.
Screeching of rail cars on curves by stick-slip and its suppression by a chemical surface treatment of the rails
Kreischgeraeusche von Schienenfahrzeugen in Kurven, ausgeloest durch das Rueckgleiten und die Moeglichkeit ihrer Daempfung durch eine chemische Oberflaechenbehandlung der Schienen
1985
7 Seiten, 6 Bilder, 2 Tabellen, 3 Quellen
Aufsatz (Konferenz)
Englisch
SCHIENENFAHRZEUG , SCHIENENSTAHL , EISENBAHNSCHIENE , EISENBAHNRAD , RADSATZ , ROLLREIBUNG , KURVE (FAHRBAHN) , FAHRKURVE , SEITENKRAFT , KONTAKTFLAECHE , REIBUNGSKRAFT , REIBUNGSKOEFFIZIENT , GERAEUSCH , GERAEUSCHDAEMPFUNG , OBERFLAECHENBESCHICHTEN , OXALATBESCHICHTUNG , PHOSPHATSCHICHT , GERAEUSCHMESSUNG , PRAKTISCHE UNTERSUCHUNG
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