空气弹簧气室压力对地铁车辆转向架焊接构架疲劳强度的影响

针对焊接构架侧梁内腔作为空气弹簧附加气室的地铁转向架,运用国际铁路联盟给出的Goodman-Smith疲劳极限法,以转向架焊接构架上盖板单边角焊缝、下盖板和内部加强筋板双边角焊缝为研究对象,在EN 13749标准的主要运营工况下,分析考虑空气弹簧气室压力交变作用对焊接构架侧梁角焊缝焊趾疲劳强度的影响。结果表明:考虑空气弹簧气室压力的交变作用时,上盖板单边角焊缝疲劳特性相比于不考虑空气弹簧气室压力的交变作用会明显恶化,而下盖板和内部加强筋板双边角焊缝疲劳特性变化不明显。因此,针对焊接构架侧梁角焊缝进行疲劳强度评估时,需要考虑空气弹簧气室压力的影响更为合理。

Influence of Air Spring Chamber Pressure on the Welded Frame Fatigue Strength for Metro Vehicle Bogie

Taking the metro vehicle bogie with the side beam inner cavity of the welded frame as an air spring added gas chamber,the Goodman-Smith fatigue limit method made by IUR(International Union of Railways)is applied to the single side fillet weld,the lower cover plate bilateral fillet weld and the internal reinforcement plate bilateral fillet weld on the welded bogie frame,to analyze the influence of the pressure alternation of air spring chamber on the fatigue strength of the weld toe for the side beam of the welded frame under the main operating conditions of EN13749.The results show that given the alternating effects of air spring chamber pressure,the fatigue properties of the single side fillet weld on the upper cover will obviously deteriorate compared with the condition without the alternating effects,while the fatigue properties changes of the lower cover plate and the inner stiffener plate with double side fillet weld are not obvious.Therefore,in fatigue strength evaluation,it is more reasonable to consider the influence of air spring chamber pressure on the side girder of welded frames.