浅谈化工备件的测绘方法

对多数化工厂来说,化工设备零件在机械设备长期运行的过程中,经常会因为受力情况和运行环境等因素而出现磨损、变形和断裂的情况。在这种情况下,使用化工备件代替设备原有的零件,是保证工厂正常运行的最好方法。但是由于化工备件并不是机械设备原有的零件,所以,制作出的备件能否替代原有机械零件,成为了化工设备工程技术人员普遍重视的问题。而想要使化工备件能够被正常的应用于化工设备上,就需要掌握好化工备件的测绘方法,从而制作出合格的备件。

化工装置备件需求预测及库存优化模型研究

备件需求预测和库存优化问题在化工装置中占据了重要且困难的位置,其影响深远,涵盖了经济效益和设备运行的稳定性。第一章对此提出背景与价值阐述,并对已有的国内外研究现状作了详实的概述。针对备件需求的特性,构建了一种结合统计及人工智能的需求预测模型,并对其效果进行了比较与优化。涉及到库存优化模型,经济批量模型和风险管理模型在第三章中得以引入,各模型的对比分析让我们找到了更加有效的优化路径。而第四章,是模型转化为实际应用的地方。真实的数据采集与分析带来了可靠的验证,证实了所构建模型的实用性与有效性的并存。在第五章,我们进行了更为全面的通用性和适用性分析,并探讨了模型存在的局限性和可能的改进方向。最后,通过对研究工作的总结和对结果的评价,我们确认本研究能为化工装置备件的需求预测和库存优化提供有益的理论和实证支持。

关于加强化工仪表备件管理的思考

化学工业是一项支撑国民经济建设和工业的重要行业,化学仪表备件是保证化学工业顺利开展的基础,但是目前我国的化工仪表备件的管理工作还不够完善,存在诸多漏洞,笔者结合相关的工作经验,对重点的问题进行了分析,并在分析的基础上进一步提出了解决的办法。

Microstructure of partially remelted billet of AM60 alloy prepared with self-inoculation method

The billets of AM60 alloy, prepared with self-inoculation method, were partially remelted into semisolid state. Effects of process parameters on remelting microstructure of semisolid billet were investigated. Experimental results show that the solid particles obtained with self-inoculation method are in smaller grain size and globular shape after partial remelting, compared with those prepared with other casting methods. In the optimized process conditions, the average size of solid particles of partially remelted billet is 65 μm, and the shape factor is 1.12. The process parameters, i.e. pouting temperature, addition amount of self-inoculants, and the slope angle of multi-stream mixing cooling chalmel have influence on the microstructure of partially remelted billet. The optimized temperature is from 680 ℃ to 700 ℃, addition amount of self-inoculants is between 5% and 7% （mass fraction）, slope angle of multi-stream mixing cooling channel is between 30° and 45°, with which the dendritic microstructure of as-cast billet can be avoided, and the size of solid particles ofremelted billet is reduced.

On the nature of tip clearance flow in subsonic centrifugal impellers

Increasing demand for downsizing of engines to improve CO2 emissions has resulted in renewed efforts to improve the efficiency and expend the stable operating range of the centrifugal compressors used in petro-chemical equipment and turbochargers. The losses in these compressors are dominated by tip clearance flow. In this paper, the tip clearance flow in the subsonic impeller is numerically investigated. The nature of the tip clearance in inducer, axial to radial bend and exducer are studied in detail at design and off-design conditions by examining the detailed flow field through the clearance and the interaction of the clearance flow with the shear effect with the endwalls. The correlation between blade loading and span wise geometry and clearance flow at different locations are presented.