共查询到20条相似文献,搜索用时 156 毫秒
1.
2.
3.
分析了望远镜镜身的结构,提出了塑件成型及模具设计的关键点,设计了模具的整体结构。设计了可相对运动的组合式型芯,以增加内抽芯机构的运动空间,通过塑件推出时带动螺纹滑块的移动实现了内侧抽芯。设计了矩形型芯镶块、加工了避空结构,采用螺钉固定,解决了狭小空间安装小型芯的问题,避免了模具干涉。采用了锥面配合,提高了模具的定位精度,减小了配合件的摩擦。经生产验证,该模具生产的塑件质量满足图纸要求。 相似文献
4.
张星 《锻压装备与制造技术》2013,48(3):41-43
提出了研制高速热冲压液压机的必要性,确定了高速热冲压液压机的总体设计方案,详述了此类液压机的液压原理及其应用。该产品的研制成功,给国内热冲压成形工艺的研究提供了高性能的设备,同时提高了液压机的生产效率,降低了液压机的能耗,得到了国内外广大客户的认可。 相似文献
5.
6.
镁合金熔体防氧化燃烧技术的进展 总被引:9,自引:1,他引:9
综述了相关文献,介绍了镁合金氧化燃烧的机制,总结了在熔炼过程中防止镁合金氧化燃烧的各种技术,并对其利弊作了分析,指出了未来发展的方向. 相似文献
7.
针对自磨机传动轴端漏油的问题,提出了引流回源的导油建议,通过引流回源,彻底解决了漏油的问题,保证了设备的正常运转,减轻了工人的劳动强度,并取得了一定的经济效益. 相似文献
8.
介绍了盖板零件的结构工艺,分析了零件上的4个螺纹孔的工艺要求,针对4个螺纹孔的加工,通过采用专用的夹具,简化了生产零件的模具结构,实现了零件产品的最终要求,保证了质量,同时也提高了效率、降低了成本。 相似文献
9.
10.
根据工程机械液压系统故障诊断的特点,建立了液压故障诊断专家系统。提出了利用故障定位流程图作为专家系统诊断知识的表示方式,研究了图形化的知识库生成工具Auto Flowchart,构建了诊断知识数据库,设计了故障诊断专家系统的结构,开发了基于流程图知识表示的故障诊断专家系统。有效解决了传统专家系统知识获取困难的问题;实现了液压系统的故障定位;方便了诊断知识的维护与更新,提高了查找故障的准确率及效率。最后,以QYJ40B起重机为例进行了应用,结果表明该方法有效可行。 相似文献
11.
12.
采用现场实测和计算机数值模拟找出了铸钢车轮及齿轮产生的裂纹的原因,提出了要应的防止措施,并在生产中得到验证,使废品率下降,显著提高了经济效益。 相似文献
13.
对重钢炼钢厂所生产的低碳低硅钢在浇注过程中水口结瘤的原因进行了分析,在分析的基础上,提出了相应的控制措施。防止水口结瘤的控制措施实施后,因中包水口结瘤所致的责任事故大幅度降低,单中包浇注炉数也由原来的6~7炉提高到11~12炉,取得了较好的效果。 相似文献
14.
J. I. Iribarren Laco F. Liesa Mestres F. Cadena Villota L. Bilurbina Alter 《工业材料与腐蚀》2004,55(9):689-694
A detailed study of the corrosion phenomena of carbon steel has been investigated in this work by means of the comparison of field and laboratory tests. Two areas of the metropolitan area of Barcelona (Spain) were selected to carry out the field tests, whereas two different solutions of sodium chloride and sodium hydrogen sulfite were used to simulate the field conditions by means of cyclic laboratory tests. The corrosion rate has been evaluated from the weight loss of the specimens and the morphology surface has been visualized by optical and scanning electron microscopy. Corrosion products and contaminants have been analyzed by X‐ray diffraction and energy‐dispersive X‐ray spectroscopy, respectively. The penetration results can be adjusted to the Passano equation and the corrosivity degree can be assigned in accordance with ISO standards. A correlation between field and laboratory tests has been found, by comparing the specimens with the same degree of corrosion, showing the validity of the accelerated laboratory tests in order to simulate the field conditions. 相似文献
15.
采用电镀方法制备铜-铋复合涂层。由于铋在铜中的溶解度极低,因此涂层具有两相混合结构。研究铜在铜一铋复合涂层中的晶体结构和晶格参数,测试涂层的力学性能,并与铜涂层进行了比较。结果表明,电镀参数对涂层的力学性能影响较大。在电流密度为50mA/cm2,电镀时间为20min时,铜涂层的硬度为HV_(50)165,而铜一铋复合涂层的硬度提高到HV_(50)250;铜-铋复合涂层的耐磨性也相应提高。 相似文献
16.
Pengfu Tan 《JOM Journal of the Minerals, Metals and Materials Society》2011,63(12):51-57
A series of technical improvements have been implemented to address the issue of high copper losses in rotary holding furnace
(RHF) slag, which were experienced at the Xstrata Copper Smelter at Mount Isa in 2007 and 2008. The copper losses in smelting
slag in the RHF were more than 3% in 2006 and 2007. Thermodynamic models and viscosity models have been applied in the operation
of Xstrata Copper Smelter in Australia. The theory of RHF key performance indicators has also been developed to reduce the
copper losses in RHF slag. The RHF KPIs Theory has been applied in Mount Isa Copper Smelter. The copper losses in RHF slag
dropped from 3.1% in 2007 to 0.76% in April 2009. The average copper loss in RHF slag in 2009 and 2010 was about 0.9%. 相似文献
17.
In this paper, forging of helical gears has been investigated. The forging process of helical gears has been classified into
two types of operations: guiding and clamping. The two types of forging of helical gears have been analyzed by using the upper-bound
method. Kinematically admissible velocity fields have been developed in which an involute curve has been introduced to represent
the tooth profile of the gear. Numerical calculations have been carried out to investigate the effects of various parameters
such as module, number of teeth, helix angle and friction factors on the forging of helical gears. Some forging experiments
were carried out with commercial aluminum alloy to show the validity of the analysis. Good agreements were found between the
predicted values of the forging load and those obtained from the experimental results. 相似文献
18.
Uma Batra Subrata Ray S.R. Prabhakar 《Journal of Materials Engineering and Performance》2007,16(4):485-489
The influence of austenitization and austempering parameters on the impact properties of copper-alloyed and nickel-copper-alloyed
austempered ductile irons (ADIs) has been studied. The austenitization temperature of 850 and 900 °C have been used in the
present study for which austempering time periods of 120 and 60 min were optimized in an earlier work. The austempering process
was carried out for 60 min for three austempering temperatures of 270, 330, and 380 °C to study the effect of austempering
temperature. The influence of the austempering time on impact properties has been studied for austempering temperature of
330 °C for time periods of 30-150 min. The variation in impact strength with the austenitization and austempering parameters
has been correlated to the morphology, size and amount of austenite and bainitic ferrite in the austempered structure. The
fracture surface of ADI failed under impact has been studied using SEM. 相似文献
19.
《Metallography》1985,18(2):171-181
Grain structures in splat-quenched samples of pure aluminum and a dilute aluminum-manganese alloy have been studied, and the effect of heat treatment on grain size has been investigated. The quenched samples were examined by a novel technique allowing surface structures and grain structures to be observed simultaneously, and interesting discrepancies between these were revealed. The grain structures showed considerable resistance to grain growth on heat treatment. This has been explained and the surface and grain structures reconciled on the basis that the material self-anneals to a considerable extent immediately following solidification. The scope of this study is extended to characterize the relationship between grain structures in consolidated and extruded Al-1.3% Mn and the structure of the starting material. 相似文献