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1.
330MW汽轮发电机轴承振动对汽轮机整体使用状况有直接影响,要想提高我国电厂生产水平,电厂必须结合实际发展状况对330MW汽轮发电机轴承振动的原因进行深入分析,在明确330MW汽轮发电机轴承振动产生的原因后,针对原因采取有效解决措施,为提高330MW汽轮发电机运行水平打下坚实的基础。本文从330MW汽轮发电机轴承振动产生的原因着手,对相关处理措施做了总结介绍。  相似文献   

2.
汽轮发电机密封瓦与发电机转子的碰摩是引起汽轮发电机异常振动的主要原因。本文以某电厂试运期间汽轮发电机8瓦振动大的处理方法,联系密封瓦结构特点,在此基础上通过对密封瓦的力学分析阐述密封瓦产生碰摩的机理和主要原因,为解决密封瓦碰摩引发振动的问题提供一定的理论指导。  相似文献   

3.
新安装或大小修后的水氢冷汽轮发电机组,如果发电机振动是由底部载荷分布不均造成的,如果通过传统的增、减发电机底脚垫片厚度及位置调整汽轮发电机对轮中心及调整杨度,及张口,这样会破坏原有发电机定子低载负荷的合理分布,造成发电机底脚支撑刚度下降,更会加剧电机的振动,因此,只有测量发电机定子底脚及支撑的载荷分布,才能消除发电机的振动。本文针对发电机振动大的原因进行全面分析并加以处理,以便为同类机组具有借鉴之处。  相似文献   

4.
对于汽轮发电机定子铁芯设计的研究,主要是为了防止汽轮发电机在运行的整个过程当中,定子铁芯由于不同振动频率与其径向发电机频率产生共振现象,进而对发电机造成不同程度的损坏。就目前来看,该方向的研究内容较少。本研究通过对汽轮发电机定子铁芯设计中几个问题的探讨,进而提出合理的补充技术手段。  相似文献   

5.
汽轮发电机轴振动大的引发因素很多,必须从复杂的表象中查找出主要因素。文章对印尼棉兰Pangkala.susu电厂1号机组汽机满负荷振动情况进行了分析,并针对电厂大型转动机械的振动进行了探讨。  相似文献   

6.
朱敬伟 《价值工程》2015,(13):140-142
氢内冷汽轮发电机漏氢量(率)的大小直接影响发电机的安全、经济运行,漏氢量(率)是汽轮发电机组运行的主要技术指标之一,也是发电机安全性评价的一个重要指标。本文着重介绍了大唐吉林珲春发电厂运行的产两台国产330MW发电机定冷水箱含氢量超标的原因分析和防范措施以及治理330MW氢内冷发电机漏氢的方法。  相似文献   

7.
振动是汽轮机组故障中较为棘手的难题,这套汽轮发电机组应用于某国外发电船上,在试车过程中,齿轮箱中的大齿轮振动一直超标,已经影响到机组交付运行。采用状态监测技术对某船用汽轮发电机组进行频谱分析和故障辨别,判断出齿轮箱中大齿轮振动的主要原因。之后采取加固公共底盘,更换饶性联轴器等措施后,解决了机组振动异常的问题。  相似文献   

8.
黄凤娟 《价值工程》2011,30(6):80-80
本文分析了汽轮发电机定子冷却水系统主要设备的特点和工作原理,并对汽轮发电机定子冷却水系统的运行状况进行测试及分析。  相似文献   

9.
随着科学技术的发展,在现代社会中人类对电能的需求量越来越大,因此加大对电力事业的发展力度迫在眉睫。在发电站中,传统的小功率汽轮发电机发出的电量已经远远不能满足现代人们在生活生产中的用电需求,因此汽轮发电机的改进创新也自然是水到渠成。与此同时,在汽轮发电机在发电的过程中,还必须对汽轮发电机密封油系统进行优化设计,从而才能保障发电机的正常运行。本文首先对发电机组密封油系统进行了详细的介绍,然后就其中存在的缺陷及危害进行了深入分析,并提出了相关的预防措施,以供同行探讨。  相似文献   

10.
1#发电机组振动分析及处理   总被引:1,自引:0,他引:1  
通过对1#发电机组在接缸检修后试车过程中出现暖机、过临界工况下轴系振动超标分析,借助振动信号采集分析装置,采取不停车轴系动平衡分析,很好的解决了轴系的振动问题。为解决汽轮发电机组检修试车中发生的振动问题寻找到一条经济快捷的解决方法。  相似文献   

11.
En este estudio se analiza el incumplimiento del salario mínimo durante el periodo 2003–2012 en diez países de Europa central y oriental con salario mínimo obligatorio nacional. A partir de los datos de EU‐SILC y la metodología propuesta por Bhorat, Kanbur y Mayet (2013), se cuantifica la incidencia y magnitud del incumplimiento. Se realizan análisis de regresión sobre determinantes individuales, laborales y macroeconómicos. Aunque la incidencia permanece relativamente baja, los trabajadores a los que se dirigen las políticas de salario mínimo parecen los más expuestos a su incumplimiento. Con el tiempo, una mayor incidencia se asocia a una razón más alta entre salario mínimo y salario medio.  相似文献   

12.
While a growing body of research analyses the functional mechanisms of the cultural or creative economy, there has been little attention devoted to understanding how local governments translate this work into policy. Moreover, research in this vein focuses predominately on Richard Florida's creative class thesis rather than considering the wider body of work that may influence policy. This article seeks to develop a deeper understanding of how municipalities conceptualize and plan for the cultural economy through the lens of two cities held up as model ‘creative cities’ — Austin, Texas and Toronto, Ontario. The work pays particular attention to how the cities adopt and adapt leading theories, strategies and discourses of the cultural economy. While policy documents indicate that the cities embrace the creative city model, in practice agencies tend to adapt conventional economic development strategies for cultural economy activity and appropriate the language of the creative city for multiple purposes.  相似文献   

13.
Despite the establishment of high-tech multinational enterprises (MNEs) in Ireland since the late 1950s, the country did not succeed in closing the technological gap with most of its EU counterparts. The weak National System of Innovation (NSI), and in particular low business and government R&D levels, combined with a lack of research and technology linkages between MNEs and indigenous firms, explain these poor results. However, the Shannon region in the West of the country presents some specific institutional characteristics that could theoretically make the region a strong technological enclave. The various actors in the region - i.e. the administrative, financial, political and research institutions, as well as the business organizations - have indeed infused a new type of economic development. After a brief review of the available concepts and models articulated around these actors and their interrelationships, the paper analyses whether the Shannon region, taken as an illustrative example, mirrors a specific economic and technological localized setting. The study is based on a survey of indigenous and foreign firms.  相似文献   

14.
This article reviews discrimination and diversity research published in Human Resource Management (HRM) over the past 60 years. While discrimination and diversity are very different constructs, it is often informative to study them together, because when people recognize each other's diversity, this can result in bias, stereotyping, and discrimination. We conducted bibliographic searches for terms related to discrimination and diversity as well as a manual search through every title and abstract published in HRM over the last 60 years to assess article relevance. The search resulted in 135 research articles with 136 unique studies (i.e., samples) which are reviewed in this article. Sex and race are the demographics that have been examined the most in HRM, while religion has been examined the least. Moreover, the number of studies examining lesbian, gay, bisexual, transgender, and queer (LGBTQ) employees in the workplace in HRM has grown quickly within the past 10 years, culminating in a recent meta‐analysis. Our review looks at some of the earliest research published, the most recent research published, and the overall trends we identified in the research over the years for both discrimination and diversity articles. We then make future research suggestions and recommendations to advance the study of discrimination and diversity in the coming years.  相似文献   

15.
The Early History of the Cumulants and the Gram-Charlier Series   总被引:2,自引:0,他引:2  
The early history of the Gram-Charlier series is discussed from three points of view: (1) a generalization of Laplace's central limit theorem, (2) a least squares approximation to a continuous function by means of Chebyshev-Hermite polynomials, (3) a generalization of Gauss's normal distribution to a system of skew distributions. Thiele defined the cumulants in terms of the moments, first by a recursion formula and later by an expansion of the logarithm of the moment generating function. He devised a differential operator which adjusts any cumulant to a desired value. His little known 1899 paper in Danish on the properties of the cumulants is translated into English in the Appendix.  相似文献   

16.
This paper evaluates the impact of service sector trade liberalization on the world economy by a ten-region, eleven-sector CGE model with import embodied technology transfer from developed countries to developing countries. Simulation results show that service sector trade liberalization not only directly affects world service production and trade, but also has significant implications for other sectors in the economy. The major channel of the impact is through inter-industry input-output relations and TFP growth induced from services imported by developing countries from developed countries, which may be embodied with new information and advanced technology.  相似文献   

17.
Former industrial cities in the West are employing gentrification as urban policy. In these policies, women and families currently play an important role as gentrification pioneers. In my analysis of Rotterdam in the Netherlands, I propose the term genderfication to understand the gender dimensions of this process. Genderfication refers to the production of space for different gender relations. I analyse Rotterdam's urban planning program for becoming a ‘child‐friendly city’, which entails replacing existing urban dwellings with new, larger and more expensive ‘family‐friendly homes’ as a strategy for urban re‐generation. Urban re‐generation supplements regeneration in the form of material and economic restructuring, and refers to the replacement of part of the current population by a new and better suited generation. The ‘child‐friendly city program’ is considered in tandem with punitive ‘youth policies’.  相似文献   

18.
Hierarchical Models in Environmental Science   总被引:6,自引:0,他引:6  
Environmental systems are complicated. They include very intricate spatio-temporal processes, interacting on a wide variety of scales. There is increasingly vast amounts of data for such processes from geographical information systems, remote sensing platforms, monitoring networks, and computer models. In addition, often there is a great variety of scientific knowledge available for such systems, from partial differential equations based on first principles to panel surveys. It is argued that it is not generally adequate to consider such processes from a joint perspective. Instead, the processes often must be considered as a coherently linked system of conditional models. This paper provides a brief overview of hierarchical approaches applied to environmental processes. The key elements of such models can be considered in three general stages, the data stage, process stage, and parameter stage. In each stage, complicated dependence structure is mitigated by conditioning. For example, the data stage can incorporate measurement errors as well as multiple datasets with varying supports. The process and parameter stages can allow spatial and spatio-temporal processes as well as the direct inclusion of scientific knowledge. The paper concludes with a discussion of some outstanding problems in hierarchical modelling of environmental systems, including the need for new collaboration approaches.  相似文献   

19.
20.
When sampling a batch consisting of particulate material, the distribution of a sample estimator can be characterized using knowledge about the sample drawing process. With Bernoulli sampling, the number of particles in the sample is binomially distributed. Because this is rarely realized in practice, we propose a sampling design in which the possible samples have a nearly equal mass. Expected values and variances of the sample estimator are calculated. It is shown that the sample estimator becomes identical to the Horvitz–Thompson estimator in the case of a large batch-to-sample mass ratio and a large sample mass. Simulations and experiments were performed to test the theory. Simulations confirm that the round-off error due to the discrete nature of particles is negligible for large sample sizes. Sampling experiments were carried out with a mixture of PolyPropylene (PP) and PolyTetraFluorEthylene (PTFE) spheres suspended in a viscous medium. The measured and theoretical variations are in good agreement.  相似文献   

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