针对刨刀使用寿命短、影响煤炭生产经济效益的实际问题,为了探究刨刀损坏原因,提出了用两个正态随机分布和其标准相关函数来近似代替伽马分布,建立了刨刀刨削硬质包裹体随机载荷的数学模型,根据刨煤理论建立了刨刀的有限元分析模型,利用Maltab软件对MK97 -002型刨刀进行仿真,得到了刨刀的随机载荷曲线及其统计值,并以最大随机载荷对刨刀加载,通过计算机仿真和有限元分析获得了刨刀上的应力及应变云图.研究发现:刨刀的随机载荷及其波动大小依次为刨削阻力、进刀阻力、侧向阻力,且载荷波动较大,最大应力和最大位移均出现在刨刀合金头处.分析认为,该处是刨刀的薄弱环节,应力集中及其应变是导致刨刀损坏的主要原因,焊缝处的损坏由疲劳失效所致,而载荷波动是引起疲劳破坏的根源.结果表明,仿真计算与实际情况相符,所建模型正确,仿真结果可信.%The plow tool has short service life, which directly influence the economic benefits of coal production. In order to research the causes of plow tool damages, random loads mathematic models of planning hard parcels by a plow tool were presented, by using an approximate Gamma distribution-a Chi-square distribution described by two normal random distributions and their standard correlation functions. The finite element analysis model of plow tool was established based on the theory of coal planning. The random load curves and statistical values of MK97 -002 type plow tool were obtained with Matlab. Then, with the largest random load applying for plow tool, their stress and strain nephograms were obtained by computer simulation and finite element analysis. The study found that the magni-tude of resistances and their fluctuation on plow tool were in the following order; planning resistance, feed resistance, and lateral resistance, form large to small, and the loads fluctuated badly. The maximum stress and the maximum displacement of plow tool all presented at alloy blade. Analysis suggests that the alloy blade is the weak link of plow tool and its stress and deformation are the main damage causes of plow tool. The damage at weld seam is caused by fatigue failure and the load fluctuation is the root fatigue-damage cause of plow tool. The results show that the simula-tion calculation agrees with the actual situation, the simulation results are correct and the method is practical and fea-sible.
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