提高斗提机链条链板疲劳强度的挤孔试验

Extrusion Hole Test for Improving Fatigue Strength of the Chain Plate of Bucket Lift

高速重载斗式提升机链条,在交变载荷作用下,经过几十万次甚至一百万次以上冲击,最后的失效形式大部分是链板疲劳断裂,而国内外尚未见此类链条疲劳试验机的报道。开展链条链板的受力分析、挤孔后的弹塑性分析、残余应力的分析以及弹塑性状态下的位移计算等,为进行实际工况试验提供了理论依据;设计不同过盈量的挤孔芯棒加工链板,并对相关数据进行统计分析,进一步探究了挤孔过盈量的范围;对一定过盈量的挤孔链板进行拉伸试验,验证了链板的抗拉强度是否会受到影响。

Under the alternating load,the chain of high-speed heavy-duty bucket hoist passes through hundreds of thousands or more shocks,and the final failure mode is mainly chain plate fatigue fracture.There is no report on this kind of chain fatigue tester at home and abroad.Through force analysis of chain plate,theoreti⁃cal basis is provided for elastic-plastic analysis after extrusion,analysis of residual stress,calculation of dis⁃placement under elastic-plastic state,and actual working condition test etc.Through the design of extruded-hole mandrel with different interference,statistical analysis is carried out on relevant data to further explore the range of interference of extruded holes,and tensile test is carried out on extruded-hole chain plate with certain interference to verify whether the tensile strength of chain plate will be affected.