PREVENTION OF DERAILMENT OF GOODS WAGONS ON DISTORTED TRACKS. TWO-AXLED GOODS WAGONS SUBJECTED TO SIMULTANEOUS STRESSES DUE TO TRACK DISTORTION AND TO TRANSVERSE COMPONENTS OF THE FORCES OF THE AUTOMATIC COUPLER. DYNAMIC EFFECTS OF TRACK DISTORTIONS
Reports which were published by the B 55 Specialists Committee so far were concerned with the performance of two-axled wagons fitted with screw couplings and side buffers during quasi-static running on twisted track. This report comprises the results of more recent investigations which are described in detail in three appendices to this report, namely: the performance of two-axled wagons during quasi-static running on twisted track when exposed simultaneously to components of forces in the transverse direction as they may arise from the longitudinal compressive forces of the automatic coupler; the performance of two-axled wagons and bogie wagons negotiating twisted track at higher speeds. The quasi-static tests permitted a value for the coefficient of the safety against derailment to be proposed for tyre profiles with a flange coning angle of 70 degrees. This value is almost half as high again as that for a flange coning angle of 60 degrees; the general introduction of tyre profiles with a flange coning angle of 70 degrees is therefore recommended urgently to enhance the safety against derailment. The representation of the results obtained from the quasi-static tests is supplemented by formulae and a nomogram which make it possible to ascertain for a wagon the transverse components of the coupling forces acceptable on track with a given twist, or the track twist safely negotiable under the effect of a given transverse component of the coupling force. Dynamic tests at speeds up to 120 km/h have shown that the limit value which is valid for quasi- static conditions was exceeded during short periods without resulting in derailment. The discontinuous measuring method did not however, give a trustworthy indication of the actual maximal values and the duration of overstepping of the limit value. These tests and the theoretical investigation have both shown that a certain coincidence of defects (a succession of two defects) may impair the safety against derailment to a particularly severe extent.
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International Union of RailwaysOffice of Research and Experiments
- Publication Date: 0
- TRT Terms: Couplers; Deformation; Derailments; Dynamics; Freight cars; Prevention; Rail (Railroads); Railroad tracks; Stresses; Tests; Torsion; Train track dynamics; Two axle cars; Wheels
- Old TRIS Terms: Automatic coupling; Question b55; Track deformation; Wheel stresses
- Subject Areas: Railroads; Security and Emergencies; Vehicles and Equipment;
- Accession Number: 00052996
- Record Type: Publication
- Source Agency: International Union of Railways
- Files: TRIS
- Created Date: Nov 3 1976 12:00AM