锚固牵引装置主支撑梁有限元强度分析及优化设计

锚固牵引装置(自移设备列车动力装置)的机械结构主要由顶梁、主支撑梁、底座及主支撑立柱四部分组成。利用ANSYS Workbench模块,以锚固牵引装置的主支撑梁为研究对象,对其进行静力学分析,得出在不同坡度、不同高度下主支撑梁的强度、刚度和安全系数均符合工程要求。再结合主支撑梁的模态分析得出主支撑梁在工作条件下不会发生共振,进一步验证了主支撑梁的可靠性。最后对主支撑梁进行多目标优化,优化结果使得主支撑梁在强度、刚度上得到提升,质量有所下降。因此对锚固牵引装置进行有限元强度分析及优化设计,对提高井下工作效率,减少因运输设备失效造成的事故发生具有重要意义。

Study on the feeding habit and trophic level of main economic invertebrates in the Huanghai Sea

The stomach contents of 14 main invertebrates in the Huanghai Sea are analyzed. The results indicate that: (1) the examined predator species were all omnivore with wide md range, showing no obvious selection for specific fed items, (2) on the basis of their ecological habitat, the predators could be classified into 5 different types, i.e., benthoelagic and planktopelagic animals, nektopelagic and planktopelagic animals, benthopelagic animals, nektopelagic and benthopelagic animals, and nektopelagic animals and (3) the trophic level of the 11 predator species, including Crangon affinis, Palaemon gravieri, Penaeus orientalis, Trachypenaeus curvirostris, Metapenaeopsis dalei, Portunus trituberculatus, Charybdis bimaculata, Oratosquilta oratoria, Sepia andreana, Loligo beka and L. japonica ranged from 2. 30 to 2. 72, belonging to low carnivore (trophic level: 2. 0~ 2. 8), whereas that of the other 3 predator species, including Sepia esculenta, Sepiella maindroni and Todarodes pacificus were in the range of 2. 86~ 2. 97, belonging to mid-carnivore (trophic level: 2. 9 ~3. 4).

液压支架顶梁智能焊接关键工序分析

针对某企业机器人智能焊接中需要每次重新编程、无法重复使用已编好程序实现自动焊接的问题,以该企业液压支架顶梁焊接为例,分析焊接流程中的关键工序,采用故障树方法对机器人焊接工序流程进行建模,获得各个焊接工序重要程度以及故障树模型中各种故障因素,通过重要度分析,获得影响顶梁焊接质量的关键工序,然后得到改进焊接流程的关键点和主要因素并进行针对性改进,最终实现机器人智能焊接。

残余奥氏体对铁路货车轴承性能的影响

通过对比国内外评价轴承热处理组织指标的差别,说明残余奥氏体含量与金相组织级别之间的关系。阐述残余奥氏体的作用、形成机理,分析残余奥氏体对铁路货车轴承接触疲劳寿命、力学性能和尺寸稳定性的影响。提出将轴承残余奥氏体含量控制在10%~20%为宜,检测位置为成品轴承滚动表面下0.2 mm处。