偏载对铁路货车轴颈轴承概率寿命的影响

偏载恶化车辆服役动力学性能，增加零部件服役载荷，降低动力部件服役寿命。参考标准EN13103/EN 13104/JIS E 4501 进一步考虑惯性和结构细节效应，建立新的铁路货车及轮对的偏载简化动力学模型。依据这一模型建立包含轴颈轴承在内的铁路货车相关动力部件服役载荷确定方法。结合标准ISO 281，考虑铁路货车双列圆锥滚动轴承的产品特点及顺序轮对服役的载荷特点，建立轴承载荷和概率寿命的评估方法。通过某35.7 t轴重铁路货车轴颈轴承的偏载效应分析，揭示了偏载引起轴承谱当量载荷非线性增长、概率寿命呈非线性下降，要控制寿命下降率低于30%，服役管理的临界横向偏载程度不大于15 mm，临界纵向偏载程度不大于30 mm。

Skewed Loading Effect on the Probabilistic Lives of Journal Bearing of Railway Wagon

Skewed loading will aggravate railway wagon’s dynamic properties to result in an increasing of the dynamic loads and decreasing of lives in service of the parts and components subject to vehicle’s kinetics. New concise dynamic models are constructed in sequent for the wagon and then for wheelsets with skewed loading under consideration of vehicle inertia and detailed transferring forces, referred to the existent codes EN 13103/EN 13104/JIS E 4501. Method is then established for determining loads of vehicle related kinetic parts and components including the journal bearings. Estimation methods for the loads and probabilistic live of the bearings is proposed on referring to the loading and probabilistic life L10 theory in the code ISO 281. An assessment practice is performed for the journal bearings of a freight car with 37.5 t axle weigh incorporated skewed loading cases. Results show a non-linear increasing effect on the spectral equivalent radial loads and a non-linear decreasing effect on the probabilistic lives of the bearings. Critical criteria of lateral 15 mm and longitudinal 30 mm should be controlled to keep the decreasing rate of life in a range of 30 percent.