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181.
刀具损伤监控技术的发展概况 总被引:1,自引:0,他引:1
宋小中 《云南工业大学学报》1989,(1)
本文论述了刀具损伤监控技术发展的必要性,并在此基础上介绍了目前出现的几种刀具损伤监控装置。 相似文献
182.
静电无处不在。双面彩色相纸由于采用聚丙烯作为基材,和单面相纸相比在分切中更容易产生静电。严重的静电斑会造成产品报废。在环境湿度、设备接地、分切速度和静电消除器安装这四个方面,采取相应的措施可有效的控制分切过程中静电的产生,保障相纸的表观质量。 相似文献
184.
用速度系数K对振动切削的动态切削过程进行了分析,由试验研究得出:加工硬脆材料时,关键是振动切削中的冲击作用,当K=0.308时,冲击作用最强,切削效果最好,试验结果与理论分析基本一致。 相似文献
185.
本文首先从理论上探讨了机床隔振的特点及不用固定螺栓通过机床自身重量定位的条件,而后对机床减振垫进行动态特性计算,最后通过生产实例给出验证。 相似文献
186.
187.
介绍了垂直筛板型尿素工艺冷凝液深度水解装置投产及运行情况。实际运行结果表明:装置处理能力25 m3/h,吨工艺冷凝液蒸汽耗≤300 kg,水解后废液中含氨和尿素质量分数均≤5×10-6,回收的NH3和CO2全部返回尿素装置的中压系统,吨尿素氨耗下降10~15 kg,收到了较好的节能减排效果。 相似文献
188.
《分离科学与技术》2012,47(9):1265-1274
Naturally occuring matter (NOM), a heterogeneous mixture of complex organic compounds, is invariably present in all surface and ground waters. These materials act as substrate for the growth of bacteria in the distribution system. The disinfection of such water by chlorination produces disinfection by products consisting of several halogenated compounds which are toxic and carcinogenic. As gallic acid is the building block of most NOM, its adsorptive removal from water has been studied using activated carbon columns. The operating variables studied are the hydraulic loading rate (HLR), bed depth (Z), and the feed concentration (Co). The breakthrough curves are S-shaped and the breakthrough time increases with increasing Z and decreases with increasing HLR and Co. The adsorption increases with increasing HLR and is maximum around HLR = 8 m3/hr/m2. The column design parameters such as the critical bed depth and the depth of the mass transfer zone (MTZ) as calculated using the bed depth service time (BDST) approach are found to agree fairly closely with the experimental values. MTZ is smaller for the carbon cloth indicating its better adsorption characteristics. The adsorption column parameters such as the treated volume and the mass of the carbon required for a desired effluent concentration have been determined from the column data. 相似文献
189.
190.
《Ceramics International》2020,46(2):1621-1630
This work aims to reveal the cutting performance and wear mechanisms of Sialon ceramic tools for the high-speed face-milling of GH4099, with the goal of improving this process as well as designing more advanced ceramic cutting tools in the future. At the outset of this study, several single-factor experiments were designed with speed as a variable to gather various data on such tools. Failure patterns and tool life curves were first obtained through cutting tests. Afterwards, the tools were split at their place of wear (middle of notch and 1/2 depth of cut) to prepare for further analysis. Wear morphology and element composition distribution in the depth direction of the corresponding interface were then analyzed using a field emission scanning electron microscope (FE-SEM) and energy dispersive spectrometer (EDS) to explore potential diffusion and/or chemical wear. Finally, studies were conducted into the tools’ chemical wear under specific cutting conditions, finishing with a theoretical verification based on the thermodynamic principle of chemical reactions. This research discovered that notch wear was the main failure pattern for the high-speed face-milling of GH4099 under the suitable cutting conditions. Overall, the optimal cutting speed was 1000 m/min, with a tool life of about 3 min. Compared with cemented carbide tools, the machining efficiency for Sialon ceramic tools increased by over a factor of 16. The wear mechanisms for such tools demonstrated a mixture effect of abrasive, adhesive, diffusive and chemical wear. Diffusive wear mainly occurred in their flank faces, but did not constitute the main mechanism of notch wear; chemical wear proved to be a key reason for notch wear at higher temperatures. Based on the aforementioned research, this paper concludes with a proposed comprehensive model for notch wear. 相似文献