高温敞口槽罐液位测量装置性能分析

露天高温敞口(非封闭)槽罐中的腐蚀性液体,温度高、可沉淀、液体介电常数变化频繁,液面上部充满污浊高温蒸汽,使用雷达(超声波)液位计、电容液位计测量其液位时,经常会出现测量装置死机、显示不准、冒槽等现象.吹气式液位测量装置具有使用寿命长、经济、维护工作量小,测量介质变化时测量值只比实际液位高的特点,只要安装、调试合理,可完全杜绝由于死机而造成的冒槽事故.     

磁性浮子液位计在鼓风机热井液位监测中的应用

以汽轮鼓风机热井液位监测装置改造为背景,概述了磁性浮子液位计在汽轮鼓风机热井液位监测装置中的应用,通过磁性浮子液位计和电接点液位计的比较,阐述了磁浮子液位计的工作原理以及测量优势,论证了该项改造对保证生产的稳定运行起到的作用。     

宁钢水处理液位监测系统应用完善

根据宁钢不同水系统液位计使用情况,总结出各种液位计用于不同场合的利弊,并通过对液位监测系统的陆续改造,确定了液位监测系统要根据不同的水系统、生产的重要性、工艺联锁条件等因素来综合选定。通过近几年液位监测系统的不断改进、完善及精心维护,现有的水处理液位监测系统运行稳定,能够满足现场实际需求。     

LB—352液位计的应用研究

本文介绍了ＬＢ－３５２液位计在连铸结晶器钢水液位测量与自动控制中的应用。用根据连铸结晶器尺寸、预先制做的长形试块,模拟连续铸钢过程中,结晶器内钢水液位的波动等方法,对ＬＢ－３５２液位计进行初步的标定和调试。在连铸热调过程中,对其进行与拉坯实际情况逐步迫近的细调试,最终达到了ＬＢ－３５２液位计与ＰＬＣ控制器、液压伺服系统联锁控制塞棒动作,调节由中间包流入结晶器钢水的流量,实现了结晶器内钢水液位在点达     

Deltabar FMD72电子差压液位计上市

正全球物位测量技术创始者之一Endress+Hauser日前在中国发布了全新电子差压液位测量系统——Deltabar FMD72。与传统差压液位计不同,该产品的二个压力传感器直接连接到过程设备,以无导压管、无毛细管的新颖设计,消除了传统液位计受到环境温度影响导致的测量误差,使带压罐体的液位测量更加可靠、安全而经济。传统的差压液位测量系统,例如带导压管     

浅谈加热炉汽化冷却装置汽包液位

从某热轧厂加热炉汽化冷却装置普遍存在的液位控制不好的情况出发,探讨了液位控制的重要意义。分析了排汽点的选择、液位计的选择、液位调节系统的选择等多个方面对改善液位控制效果的可行性,以保证汽化冷却装置的安全正常运行。     

加热炉汽化冷却装置汽包液位控制问题研究

山西某热轧厂加热炉汽化冷却装置普遍存在液位控制不好的情况,为此探讨了液位控制的重要意义．分析了排汽点的选择、液位计的选择、液位调节系统的选择等多个方面对改善液位控制效果的可行性,以保证汽化冷却装置的安全正常运行。     

高线步进梁式加热炉汽包液位测量技术

介绍了高线步进梁式加热炉汽包液位的四套测量系统，即平衡容器与差压变送器配套测量系统、平衡容器与双波纹管液位计配套测量系统、电接点液位测量系统、玻璃管液位测量系统。并对四套系统的测量方法、实际应用情况及测量偏差进行详细的对比分析。     

化工生产中的液位和流量测量

就化工厂实际生产中的一些液位、流量测量的现状和原理加以剖析，并就当前在液位和流量方面技术比较先进的超声波液位计、超声波流量计、电磁流量计、热式质量流量计、转子流量计、涡街流量计等加以探讨。     

增设空冷塔液位自动调节系统及阻力报警连锁系统

空冷塔是14000m3/h空分装置的重要组成设备,该设备对空透压缩过的空气进行冷却,使空气温度下降到12℃,冷却后的空气送到分子筛纯化系统除去杂质。空冷塔底部液位是一个十分重要的工艺参数,该液位的恒定是空冷塔长期运行的重要条件。原系统采用一套自动排水阀,一套就地手动排水阀对液位进行调节,一套翻板液位计对液位就地监视、中控室连锁。一旦液位异常,由于手动阀不能及时排水,无法保证液位恢复正常,加上翻板液位计性能差,连锁失控,很可能造成事故的发生,如分子筛带水等。这是生产上所不允许的。针对上述情况,对该系统做了如下改造:将翻板…     

用雷达液位计快速判断煤气管道内的积水情况

在寒冷的冬季,受蒸汽冷凝水外溢现象的干扰,不能及时发现煤气管道内积水的问题。经过对现场的勘察,决定在煤气管道地势较低、易形成积水的管段安装"雷达液位计"并将监测信号引至值班室内,实现实时监控煤气管道内的水位,确保煤气管网系统的安全运行。     

Ultrasound treatment of centrifugally atomized 316 stainless steel powders

The Bureau of Mines is studying the surface characteristics of rapidly solidified powders and the potential for surface modification of fine powders prior to consolidation. The surface modification and work hardening of fine powders were accomplished by applying high-energy ultrasound to centrifugally atomized austenitic 316 stainless steel powders suspended in liquid media. Cavitation implosion changed the surface morphology, hammering the surface and occasionally fretting off microchips of work-hardened metal. Ultrasound-cavitation work-hardened metal powder surfaces producing a strained, duplex austenite face-centered cubic (fcc)-martensite body-centered tetragonal (bct) phase structure. The amount of work hardening depended upon the quantity of ultrasound energy used, considering both power level and experimental time. Work hardening was relatively independent of the liquid media used.     

高炉长寿实用技术发展

对高炉长寿最新实用技术进行了调研、分析和总结,详细介绍了法国索拉克高炉多点垂直探针的开发、特点与应用;德国布莱梅钢铁公司热流仪的设计原理、结构、材质与应用;德国蒂森@克虏伯钢铁公司开发的炉缸渣铁液位电动势测量法.根据鞍钢实际,提出了高炉长寿建议.     

SDL料位控制技术在莱钢750m3高炉上的应用

针对750m^2高炉原有料位检测装置中称重料位检测法和振动料位检测法存在检测准确性差，仅能作为备用检测手段，而PNF-1201型核辐射料位计易发生料位测量信号故障，导致高炉休风、慢风的问题，决定采用SDL型闪烁料位计对PNF-1201型核辐射料位计进行改造，使料位检测信号的可靠性大大提高。应用表明，高炉由改造前的平均每年发生料位测量信号故障7．7次、休风12．8h、慢风41h，达到零故障．     

Improved glycemic control in intensively treated type 1 diabetic patients using blood glucose meters with storage capability and computer-assisted analyses

OBJECTIVE: To determine the effect on glycemic control in intensively treated type 1 diabetic patients using a blood glucose meter with storage capability and computer-assisted analyses. RESEARCH DESIGN AND METHODS: Glycemic control was assessed in 22 intensively treated adults with type 1 diabetes for 12 months while using a meter without memory, followed by 12 months while using a meter with memory. Log books were used to assist patients in managing aspects of the diabetes treatment plan during the first 12-month period, and computer-assisted analyses were used when the meter with memory was used. GHb levels were measured monthly throughout the 24 months of observation. RESULTS: The mean GHb level averaged across all patients during the period of memory meter use (6.4%) was significantly lower than that during the period of meter use without memory (6.9%) (P=0.0004). The change in GHb levels from each period-specific baseline level occurred at significantly different slopes (P=0.046) when adjusted for baseline GHb level. In addition, the downward trend in GHb level was greater in those patients who increased the frequency of testing the most (r=-0.54, P=0.01). CONCLUSIONS: Use of a meter with memory in conjunction with computer-generated analyses of stored blood glucose test results can lead to improved glycemic control when used by a group of intensively treated adult diabetic patients. Improvement in glycemic control was related to frequency of blood glucose testing.     

Doppler spectrum analysis versus direct femoral artery pressure measurement for rapid assessment of aortoiliac obstruction

Adequate patient selection is required to limit the clinical workload and improve the cost-effectiveness of noninvasive hemodynamic evaluation of the aortoiliac system. In a prospective blinded fashion the traditional invasive technique of direct femoral artery pressure measurements and the computerized Doppler spectrum analysis of blood flow velocities in the common femoral artery were studied. Both tests for rapid assessment of aortoiliac obstruction were compared with duplex ultrasonographic imaging, using a peak systolic velocity ratio of 2.5 to demonstrate stenoses of 50% or more. In a series of 17 consecutive patients (34 aortoiliac segments) with suspected aortoiliac obstructive disease, a good level of agreement (kappa = 0.6) was found for both methods when compared with duplex scanning. Analysis of deviations from the duplex registrations indicated an overestimation of the pathologic cases using femoral artery pressure measurements and an underestimation using Doppler spectrum analysis of blood flow velocities in the common femoral artery. Both methods were well tolerated, but femoral artery pressure measurements had a higher technical failure rate. Because of its noninvasive character and its feasibility the Doppler technique is preferred for the selection of patients for more extensive duplex sonographic investigation.     

Effects of Sulphate-reducing Bacteria on Corrosion Behaviour of 2205 Duplex Stainless Steel

The effects of sulphate-reducing bacteria(SRB)on the 2205 duplex stainless steel in the sea water and oil industry environments were studied by electrochemical impedance spectroscopy(EIS),potentiodynamic polarization and microorganism analysis.The results showed that the detected SRB was the non-spore bacillus of about 0.8μm×(1.8-2.2)μm in size and the content of S was about 7.59% in the corrosion products.SRB contributed to the corrosion evolution which caused the corrosion failure of 2205 duplex stainless steel pipe in the liquid hydrocarbon cooler.During the corrosion process,the produced H2S could significantly influence the anodic process and finally accelerate the corrosion.SEM observation indicated that the distribution of SRB on the surface of 2205 duplex stainless steel was nonuniform.X-ray photoelectron spectroscopy analysis revealed that the surface film was composed of Cr2O3,MoO3,FeS,FeS2,Fe(OH)2 and FeO after immersing the sample in the SRB medium for 14d.     

超低碳钢LF-RH双联精炼工艺的开发

介绍了唐山国丰钢铁有限公司第一炼钢厂RH投产后超低碳钢的生产工艺开发情况。通过对不同的精炼工艺路线进行对比,使用优化的LF-RH精炼工艺,实现对钢水巾C、N等元素的稳定控制,满足多炉连浇的生产组织需要。     

Plastic deformation and fracture of binary TiAl-base alloys

The mechanical behavior of binary TiAl alloys containing 46 to 60 at. pct Al has been studied in bulk materials preparedvia rapid solidification processing. Bending and tensile tests were carried out at room temperature as a function of Al concentration. A few alloys were also tested from liquid nitrogen temperature to ∼ 1000°C. Deformation substructures were studied by analytical transmission electron microscopy and fracture modes by scanning electron microscopy (SEM). It was found that both microstructure and composition strongly affect the mechanical behavior of TiAl-base alloys. A duplex structure, which contains both primary y grains and transformedγ/α ₂ lamellar grains, is more deformable than a single-phase or a fully transformed structure. The highest plasticities are observed in duplex alloys containing 48–50 at. pct Al after heat treatment in the center of theγ + α phase field. The deformation of these duplex alloys is facilitated by 1/2[110] slip and {111} twinning, but very limited superdislocation slip occurs. The twin deformation is suggested to result from a lowered stacking fault energy due to oxygen depletion or an intrinsic change in chemical bonding. Other factors, such as grain size and grain boundary chemistry and structure, are important from a fracture point of view. The results on the deformation and fracture modes as a function of test temperature are also discussed.