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1.
介绍了将有限元法应用于 NZ· LJZ2 0 -8大型生活垃圾转运站设备压缩装置挤压油缸和破碎油缸的强度和刚度分析方法 ,运用 ANSYS软件对该设备的挤压油缸及破碎油缸计算模型进行计算 ,得出挤压油缸及破碎油缸应力和变形分布图 ,并对结果进行了分析  相似文献   

2.
首先提出了矿用立爪式装载机的小臂油缸工作过程中存在的2个问题,然后针对这2个问题提出了优化方法,即采用缓冲油缸和差动油缸。用AMESim软件对缓冲油缸的效果进行了仿真分析.最后对差动油缸的速度和推力进行了计算,提出了比较合理的优化方案.  相似文献   

3.
对E/P杆“加热锻头”机床床体结构的强度、刚度进行了设计,并采用有限元方法计算了结构的应力和 位移。着重研究了前后油缸加载点的相对位移。计算表明,根据加工精度要求改进了机床的结构形式,前后 油缸加载点的相对位移明显降低;且前后油缸加载点的相对位移与载荷值呈线性变化的规律。  相似文献   

4.
针对混合臂式高空作业车变幅系统液压油缸驱动力难以显式计算的问题,借助拉格朗日方程和解析几何法对混合臂高空作业车臂架系统建立运动微分方程,得到臂架角位移、油缸行程与油缸受力随时间变化的动力学关系,在此基础上推导油缸油压、流量随时间变化的关系。给出臂架运动条件,基于最小二乘原理,运用MATLAB编程进行数值求解,得到油缸受力、油压及流量的时间历程曲线并对结果进行分析和验证。结果表明,模拟运动下油缸b1、b2、s1所受作用力较大,油缸设计时须优先对其进行强度分析;油缸b1、b2、s1油压变化也较大,油缸设计时须对其进行动强度分析;各油缸流量变化不大,可考虑使用定量泵节流调速系统。以上研究为混合臂式高空作业车臂架系统的设计及油缸选型等提供了参考依据。  相似文献   

5.
全液压铆接机是目前汽车装配生产中使用的重要设备,本文对该机工作装置重载动力油缸的结构设计、强度计算、密封等问题作了较详细分析和研究,该机已由校机械厂进行了批量生产,并用于汽车制造厂。  相似文献   

6.
三角钻臂的运动控制研究   总被引:5,自引:0,他引:5  
建立了三角臂的杆件坐标系,利用多关节闭链的约束条件建立了运动学方程,得到了由给定钻臂位置计算油缸长度的精确算式.增加油缸俯仰角的测量点后,得到缸长的简化算式,减小了油缸长度的在线计算量,应用该式可提高三角钻臂轨迹控制的精确度。  相似文献   

7.
为了探讨零件在结构上或技术上再制造的可行性,针对采用修理尺寸法在对进行再制造的零件作机械加工中要去除表面层厚度,以消除其表面缺陷及恢复其形状精度时,会在一定程度上削弱零件的强度或刚度的问题,本文选择了工程机械中的动臂油缸和转斗油缸作为研究对象,应用ANSYS有限元分析软件分别对其在缸壁厚度因机械加工减少0.5 mm和1.0 mm后的力学性能进行分析,通过计算缸体在原设计条件下的应力场和位移场,了解缸体结构加工后的应力应变情况,为采用修理尺寸法进行油缸再制造和确定缸体的再制造修理尺寸及其标准化提供理论依据。计算结果显示,缸体加工后零件最大应力处的安全系数分别为1.63、1.57和1.47、1.41,最小的数值仍然在1.2~1.5的设计安全系数推荐值范围内,表明再制造加工后的油缸缸体能满足强度、刚度要求,采用修理尺寸法进行油缸的再制造是可行的。  相似文献   

8.
液压缸筒用热处理双相钢管研究   总被引:2,自引:0,他引:2  
研究了液压缸筒用热处理双相钢管的力学性能和爆破性能,试验结果表明:热处理双相钢管经精密冷拔后制作液压缸筒,强度高、韧性好,爆破压力也主同,并且生产工艺简单,成本低,它可代替调度钢管用作煤矿液压支柱油缸等液压缸筒。  相似文献   

9.
在塑料注射成型机合模油缸的设计中 ,运用可靠性优化设计的原理 ,提出了连接螺栓组的计算方法 ,在保证连接强度可靠性的前提下 ,减少螺栓的个数或直径  相似文献   

10.
多级油缸可以做到柱塞总行程等于油缸长度的二至四倍.因此具有广阔的应用前景。本文以作者自行设计研制成功的双级油缸为例,详细提供了这种油缸的技术参数、结构及设计计算方法.为保证运动平稳性,作者在油缸内装有流量控制阀,并推导给出了其计算公式。 上述理论亦可应用于三级、四级油缸的设计计算。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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