振动测试基础上的风机动平衡实例

利用便携式振动测试分析仪,测量烧结风机转子振动信号,通过频谱分析法分析风机转子不平衡故障特征,结合风机类旋转机械转子不平衡故障振动信号的时域、频域谱特征,进一步明确风机不平衡故障的时频特征,并通过现场动平衡方法以减小风机不平衡振动。     

AG120/16RL6型鼓风机动静摩擦故障分析及处理

电动鼓风机组运行中相继出现静叶承缸径向局部摩擦故障以及平衡盘轴封片轴向摩擦故障.分析了风机结构特点、故障部位以及故障发生状况,认为风机静叶承缸发生弓形变形、机组转子对中不良以及风机转子与风缸膨胀速度差异是导致改型风机发生动静摩擦故障的原因。实施了修复方案后机组动静摩擦故障得到有效消除。     

处理风机振动问题时考虑输送介质因素的重要性

指出当风机出现振动故障时，尤其是在故障预兆期内判断故障原因时，应当结合风机输送介质的性质及特点。这对于风机故障的正确诊断和以后的选用及改进具有重要意义。     

风机振动的原因浅析

在风机的各种故障当中,由于振动引起的故障最为常见.针对风机振动的原因进行了分析,同时对存在的问题进行了改进,提高了风机的寿命,为故障的诊断和日常检验提供了重要依据.     

离心风机的故障诊断与现场动平衡

对离心风机使用振动监测设备发现的一些故障进行分析,结合风机振动类型,理论联系实际,准确判断故障位置,并介绍了失衡和不对中故障为主的风机的现场动平衡处理过程。     

风机旋转失速的故障诊断与处理

介绍了风机旋转失速的故障机理及振动特征,并对鞍钢炼铁三制粉废气风机旋转失速故障进行了精密诊断,发现风机入口管网设计不合理是导致其旋转失速的根本原因。     

安阳二炼钢抽雾风机故障分析

论述了风机产生的故障原因和分析故障的方法．以及采用的检测手段。并针对风机存在的实际问题采取了相应的解决方法,彻底解决了风机存在的问题。     

引风机振动故障的诊断与分析

利用正向推理,在可能引起风机振动的故障的全部原因中采取逐个排除的方法,找出风机轴向振动故障所在。分析振动原因就如何对此类故障进行诊断与分析进行论述。     

矿用除尘风机电机轴电流引起轴承故障的分析及处理

除尘风机运用范围较广。在除风机使用过程之中会因为多种原因而出现故障,其中电机轴电流所引起的轴承故障较为常见。在文中就结合实际案例分析了除尘风机电机轴电流引起轴承故障,并就其处理方法进行了探讨。     

状态监测与故障诊断技术在风机振动分析中的应用与探讨

风机振动是风机运行中最主要的故障之一。本文从风机振动的原因分析,现场风机振动故障解决实例等方面,阐述状态监测与故障诊断技术在实际生产中的重要性,通过状态监测提前发现问题,合理安排检修,避免设备事故的发生。     

Cause of Damage and Failures in Silo Structures

Silos are special structures subjected to many different unconventional loading conditions, which result in unusual failure modes. Failure of a silo can be devastating as it can result in loss of the container, contamination of the material it contains, loss of material, cleanup, replacement costs, environmental damage, and possible injury or loss of life. Silo damage and failures that occurred in different regions of the world are presented in the paper using illustrative photos. Also provided are a review and discussion of the common or spectacular silo failures due to explosion and bursting, asymmetrical loads created during filling or discharging, large and nonuniform soil pressure, corrosion of metal silos, deterioration of concrete silos due to silage acids, internal structural collapse, and thermal ratcheting. Silo damage and failures from several earthquakes are also presented.     

Variables and Behavior.

Comments on an article by Breland and Breland (Amer. Psychologist, 1961, 16, 681-684), stating that the authors have reported "egregious failures" to maintain some types of conditioned behavior. They attribute their failures to the prepotency of instinctive behavior over conditioned behavior. The commentator states that it is difficult to interpret most of their observations because their article has omitted relevant procedural details; however, it is clear that most of their procedures involve chains of behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

AEPIC Project: Update

Learning from our mistakes or learning from failure has become a common phrase in advice to professionals in the design and construction of buildings and civil structures. Indeed, with the recent rash of dramatic and tragic collapse failures of buildings, bridges, and other major structures, the need for that advice has become urgent! Yet, it would appear that all too many of us experience a serious loss of memory and∕or myopia when it comes to learning from our own mistakes and a rather crass indifference when it comes to learning from the mistakes or failures of others. The concept of the Architecture and Engineering Performance Information Center (AEPIC) has been developed to assist in the struggle to learn from our failures. The concept of AEPIC is predicated upon the belief that a systematic collection, collation, analysis, and dissemination of information about the performance (failure) of buildings, civil structures, and other constructed facilities will, in fact and in deed, assist us in learning from our failures: We can improve our professional practice and prevent the repetition of poor practices that contribute to failure. Founded in 1982 as a joint center of the School of Architecture and the College of Engineering at the University of Maryland, AEPIC has developed a substantial computerized data base and has created the techniques to analyze trends and disseminate the lessons about technical and procedural errors and oversights. Now, in 1986 and 1987, new research support grants will move AEPIC into a new level of service for all who support the concept of AEPIC.     

富士变频器在冷轧钢生产线的应用

文章讲述了赤峰远联钢铁有限责任公司冷轧带肋钢筋生产线的电气系统应用富士变频器取代了原有接触器,使该生产线上的电路线路简化、控制准确,缩短了现场人员维护及事故处理时间,设备故障大大减少,机器运行效率明显提高。经过运行,节省了电器配件的费用,降低了生产成本,提高了经济效益。     

Cognitive Impairments and Disordered Speech in Schizophrenia: Thought Disorder, Disorganization, and Communication Failure Perspectives.

This article posits that basic cognitive impairments in schizophrenia are more highly related to speech disorder measured as communication failures than speech disorder measured as thought disorder or disorganization. The author tested 47 schizophrenia patients and 36 control participants for sustained attention, sequencing, and conceptual sequencing ability. Their speech was also rated for communication failures, thought disorder, and conceptual disorganization. Attention and sequencing impairments, examined hierarchically, explained a substantial 38% of the variance in the communication measure of speech disorder but little of the variance in formal thought disorder or conceptual disorganization. The author concludes that (a) impairments in attention and sequencing abilities contribute substantially to schizophrenic communication failures, and (b) it is important to consider lower level cognitive "3rd variables" when examining higher level cognitive associates of speech disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of attribution of motivation in producing postsuppressional rebound.

Three studies demonstrated that postsuppressional rebound (PSR) may be both reduced and enhanced by manipulating people's attributions about why they experience difficulty during suppression. Telling participants that suppression failures indicate a high motivation to use the suppressed construct produced more PSR than telling them that suppression failures indicate a low motivation to use the construct (Study 1). Telling participants that an external stimulus would make suppression easy produced more PSR than telling them that it would make suppression difficult (Study 2). Telling participants that suppressing a stereotype is difficult and unindicative of prejudice eliminated PSR (Study 3). These results support the notion that PSR occurs because people infer from the difficulty experienced during suppression and from suppression failures that they are motivated to use the suppressed construct. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

SF6电器中气体水分含量的危害及控制措施

SF6气体被广泛应用在电气设备中,如GIS、变压器、互感器等。SF6已成为新一代的绝缘性超高压媒质。但因为气体水分超标出现被迫停机检修的案例频发,甚至因发现不及时导致电力系统内发生故障。SF6气体中水分的含量有其严格的规定,只有控制SF6气体中水分的含量,才能确保SF6电力设备安全运行。     

Search for semantic inhibition failure during sentence comprehension by younger and older adults.

The present research examined recent evidence that inhibition failures do not contribute to age-related declines in on-line text comprehension. Evaluating naming performance over a time course revealed that processes serving to eliminate thematically irrelevant information from memory in young adults were apparently deficient for older adults. Experiment 2 generalized these findings to contexts that rely on later information to disambiguate ambiguous words. Under these conditions, older adults were as able as younger adults to use context to disambiguate words. Despite the apparent disagreement between the experimental outcomes, it is argued that the present studies together are consistent and support the view that inhibition failures are unlikely to contribute to age differences in on-line sentence comprehension (at least) when the contexts are semantically constraining (i.e., self-contained). It is proposed that the detection of age-related inhibition failures may depend on the extent to which adults must rely on internally generated processing constraints. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of endoscopic third ventriculostomy in the management of shunt malfunction

OBJECTIVE: To evaluate the effectiveness of third ventriculostomy as an alternative to shunt revision in the management of shunt malfunction and infection in obstructive hydrocephalus. METHODS: All of the clinical notes of 30 patients treated with third ventriculostomy for malfunctioning or infected shunts between January 1, 1974, and December 31, 1996, were retrospectively reviewed. Third ventriculostomy was performed under fluoroscopic control in the first seven patients and endoscopically in the remainder. A successful outcome was achieved if further shunt revision surgery was avoided. The median follow-up duration was 8.7 years RESULTS: Twenty-three patients (76.7%) experienced successful outcomes, resulting in shunt independence. Of the seven failures, three were technical failures at the time of surgery and the remaining four were manifest within a median of 10 days, resulting in shunt revision. There have been no delayed failures. CONCLUSION: Third ventriculostomy is a valuable alternative to shunt revision in patients affected by obstructive hydrocephalus presenting with shunt malfunction or infection. It should be considered in all suitable cases as the first-line treatment for obstructive hydrocephalus of all causes. Because all failures were manifest within a short time, it is likely that these successes will be durable.     

水钢运输部铁渣倾翻电源控制装置的技术改进

论述分析了铁渣倾翻电源控制装置在运用中存在的问题,对其进行了技术改进,满足了罐体倾翻角与电源控制的一致性,提高了罐车和作业人员的安全系数。