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1.
在石油工业中,抽油机、抽油杆、抽油泵组合是最主要的开采装备,抽油泵的工况复杂,容易产生故障,示功图是抽油系统故障诊断中的最主要的依据。示功图反映了抽油泵的工况,通过分析示功图特征,可以判断抽油泵是否存在故障。因此,主要以抽油泵示功图故障诊断为对象展开论述,首先介绍了在两大类故障下的示功图图形,随后讨论了示功图故障诊断技术的起源与历史发展,从人工诊断到使用传统的神经网络诊断,再到使用机器学习应用在抽油泵示功图故障诊断。最后,总结了当前示功图故障诊断技术存在的问题,并展望了示功图故障诊断技术的发展趋势。  相似文献   

2.
王秀芳  管闯  王紫 《化工自动化及仪表》2013,(11):1370-1373,1409
抽油井工作环境、工作过程比较复杂,对抽油井泵示功图故障诊断时由于有些抽油井典型故障的示功图几何形状非常相似,极易产生误判,因此引入基于信息加权熵的灰度关联故障诊断算法,利用信息熵加权值来体现不同故障特征因子所含的信息量,使计算所得与标准故障的关联值变大,与其他故障尤其是易误判故障的关联值变小。实验结果表明:该方法能够减少故障误诊断,使抽油井故障诊断更加精准。  相似文献   

3.
柱塞泵是典型的往复机械。为了掌握往复式柱塞泵的工作状态,测取3S175系列柱塞泵正常工况和一些故障工况下液力端的振动信号,对其进行局域波时频处理后,得到了有价值的检测部件振动规律、一般特征以及故障特征,可用于往复柱塞泵液力端的故障诊断.  相似文献   

4.
柱塞泵是典型的往复机械。为了掌握往复式柱塞泵的工作状态,测取3S175系列柱塞泵正常工况和一些故障工况下液力端的振动信号,对其进行局域波时频处理后,得到了有价值的检测部件振动规律、一般特征以及故障特征,可用于往复柱塞泵液力端的故障诊断.  相似文献   

5.
柱塞泵是典型的往复机械。为了掌握往复式柱塞泵的工作状态,测取3S175系列柱塞泵正常工况和一些故障工况下动力端轴承的振动信号,对其进行局域波时频处理后,得到了有价值的检测部件振动规律、一般特征以及故障特征,可用于往复柱塞泵轴承的故障诊断.  相似文献   

6.
丛蕊  乔磊  张威 《化工机械》2013,40(3):285-288,308
提出了基于傅里叶描述子提取轮廓线特征的示功图故障诊断方法。利用八邻域搜索和形态学方法提取示功图轮廓线,在此基础上计算轮廓线边界点序列的归一化傅里叶描述子,保证了图像对于旋转、缩放和平移的不变性,并将其作为特征量输入到距离分类器中,从而实现故障智能诊断。实验结果表明,该方法可以有效地识别出示功图的不同故障类型。  相似文献   

7.
自来水行业对泵站机组的安全与经济性能的要求越来越高,迫切地认识到备品可靠性是满足新市场需求的重要保证,也是参与竞争的必要前提。但是机组容量的不断加大,导致了其系统和结构的复杂性不断增加。机组结构的复杂性与机组工作环境的特殊性提高了水泵故障诊断的难度。振动信号是判断水泵故障信息的主要来源,利用振动信号进行故障判断是最常用的方法。如不了解故障机理,可通过机组振动信号展开相关分析处理,对水泵常见故障预测与诊断等进行的研究。随着故障诊断技术的发展,必将使故障诊断越来越准确、越来越快速,应用也更加广泛。  相似文献   

8.
利用雷利(Rayleigh)-里兹(Ritz)公式计算了带齿轮叶轮的转子轴的一阶临界转速,并利用故障诊断频谱分析方法,采用Rockwell-Entek便携式故障诊断系统对机组振动故障进行检测,通过对离心式压缩机的振动频谱进行分析及故障诊断,探究油膜振荡引起的故障原因,提出排除方法,避免事故发生。  相似文献   

9.
潜油电泵机组产生严重的振动,会使机组出现运行故障,降低了使用寿命。本文对潜油电泵机组振动检测和故障诊断系统设计要求进行分析,并从振动检测和故障诊断系统软件、硬件设计两方面进行研究,可供相关人员参考。  相似文献   

10.
本文以杏六区东部Ⅰ块三元注入站柱塞泵为研究对象,对柱塞泵的故障原因进行分类统计,分析柱塞泵故障原因,制定出优化措施,对柱塞泵结构及维修体系进行优化,实现了柱塞泵的平稳运行,保证了注入时率。柱塞泵的工作性能和时率直接影响注入效果及驱油效果,由于三元目的液的特点,对柱塞泵的工作性能要求较高。为保证这些设备的正常运行所需的维修保养费用很大。因此对柱塞泵故障原因进行分析研究,降低成本消耗,对今后三元复合驱的推广具有重要意义。  相似文献   

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It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  相似文献   

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14.
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。  相似文献   

15.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

16.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

17.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

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以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。  相似文献   

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