连铸坯定重剪切技术的开发与应用

在连铸生产线上进行了由定尺剪切到定重剪切的连铸坯剪切技术开发与应用的研究，成功开发了上置式连铸坯定重剪切装置——钢坯称重机械手（已获专利），研究与解决了连铸生产线上N个流的被称重的钢坯是用同一台称，避免了多台称多个误差的称重数值偏差的问题；进行了定尺剪切连铸坯与定重剪切连铸坯生产过程的对比。研究结果表明：成品制作的定尺率、成材率有明显提高；同时指出这种技术的应用要求建立在过程工艺管理的平台上。     

连铸单支定重切割系统的开发与应用

2008年以来,在全国钢铁产量几何似的暴涨前提下,产能过剩、价格不断下滑造成各大钢铁厂在经营成本上不断寻求突破,除了加强能源回收利用,降低原燃料消耗等措施外,各种前沿的新技术也不断为各钢厂所应用,定重切割工艺就是其中之一.本文介绍的定重切割系统改造是借鉴了相关先进经验,由西林钢铁公司自身自动化团队着手设计、实施的,经过一年多的使用统计,完全达到了预期效果.西林钢铁集团有限公司的技术人员对炼钢连铸机剪切系统进行了全面的系统改造,利用抗高温防水防腐蚀的称重传感器在连铸机各流制作静态钢坯秤,利用液压传动系统升降钢坯秤采集铸坯重量信息,通过PLC上下位机软件处理铸坯重量、长度信息与生产工艺参数间的逻辑、数学关系,同时进行统计记录,自主研发出一套西钢专有的钢坯定重剪切自动控制系统,在更好的完成生产的需要的同时,具有实现故障率低、钢坯定重合格率高、有效的保证轧钢成材率等优点.技术实施后,铸坯单重±5 kg的合格率稳定在80%以上,棒材工序成材率提高0.15%左右,取得了极大的经济效益和良好的社会效益.     

钢坯定重剪切技术在西钢连铸机的应用

西林钢铁集团有4座转炉对应的连铸机所产钢坯一直是以"定尺的长度"作为标准进行切割。按"定尺"方式切割的钢坯,虽然各支钢坯长度相同,但是其重量并不相同。而轧钢是以钢坯重量为主要标准,钢坯重量的不同会增加钢坯在轧制过程中的浪费。为彻底解决这一问题,西林钢铁集团检修公司炼钢自动化所立项对连铸机剪切系统进行改造,开发出一套西钢专有的钢坯定重剪切自动控制系统,有效地保证了成材率。     

连铸坯在线定重切割技术工艺实践

连铸坯重量由连铸坯断面尺寸、钢坯长度及其密度三个因素决定。这三个因素又与结晶器铜管服役期内磨损程度、浇注温度、拉速、定尺切割精度和钢水成分有关。因此通过连铸坯在线称重结合定尺微调,可以控制连铸坯定重精度,达到最大程度提高轧钢钢材成材率、定尺率的目的。我厂通过自主设计研发的连铸坯在线吊钩式提升称重法获取连铸坯单支重量,及时调整定尺,配合连铸"恒温度、恒拉速"操作模式,稳定连铸坯定重,连铸坯定重准确率明显提高。     

基于WinCC组态软件的加热炉炉温优化控制的实践

针对新钢公司线材厂高线加热炉钢坯热装温度波动大影响钢坯加热质量的现状,提出在西门子WinCC组态软件平台上,利用WinCC全局脚本编辑器,编写加热炉炉温优化控制程序,并在WinCC系统下运行.实现了加热炉炉温的实时、动态、优化控制,提高了钢坯的加热质量,使钢坯出炉温度稳定在设定值的±10℃以内,同时进一步降低了燃耗和钢坯烧损,在实际生产应用中取得了良好的控制效果.     

摄像定尺测量技术在梅钢板坯测长系统上的应用

摄像定尺测量技术是通过红外摄像机远距离采集运动钢坯的图像信息，以非接触式的方式在线识别热钢坯的长度，计算机对图像信息进行模式识别程序处理，形成操作信息。梅钢炼钢厂1号连铸机目前采用此技术实现对板坯的在线自动测量、切割。     

钢坯秤的改进设计

针对棒线材生产线原有入炉钢坯秤在结构和功能上存在的问题进行分析,并提出了改进设计方案。通过对钢坯秤结构进行改进以及对称重传感器、限位装置进行合理的选择,达到快捷、自动、准确计量的目的,使钢坯秤能够更好地满足生产工艺需要。     

宁钢高炉槽下料斗秤改造

1号高炉槽下系统原设计17台料斗秤,因设计、安装、维护等各种原因,称量过程无法达到成本核算要求的称量精度。通过称重传感器重新选型、称重控制器更换,实现料斗秤称重精度在±0.5%以内的目标。     

国内第一套棒材无头轧制设备投入调试

无头焊接轧制技术是代表当今轧钢顶尖水平的高新技术,目前,世界上仅有少数几个厂家掌握了此项技术,唐钢棒材厂从意大利ＤＡＮＩＥＬＩ公司引进了这项技术,使唐钢成为亚洲第三家、中国第一家实现无头焊接轧制的生产厂,目前己进入调试和试生产阶段。 所谓无头焊接轧制就是将传统轧钢生产中使用的定尺钢坯（长度根据加热炉规格型式而定）,在进入粗轧机以前,通过钢坯焊接机将前后两根钢坯的尾、头焊接在一起（此时,前根钢坯的头部己进入粗轧机）,并去除焊瘤,作为一根钢坯进入粗轧机,从而实现无头轧制,基本上可实现无间隙轧制,可大…     

西钢集团第一炼钢厂对连铸实施拉速定尺改造获得成功

近日,西钢集团组织对连铸机实施拉速定尺改造获得成功。长期以来,连铸机定尺切割主要依靠摄像定尺来实现。由于摄像定尺受外部因素影响较大,出现钢坯切不断、外部因素遮挡摄像采集点等情况时都无法实现准确切割,     

高炉重量布料准确度的提高

为提高高炉重量布料控制准确度,对称量罐测量环节进行研究,提出了称量系统的调整和维护方法。通过对称量系统进行分析和优化,使测量准确度满足了重量配料的要求,保证了高炉按重量布料方式的实现。     

不断轨动态轨道衡的应用

介绍了800t不断轨动态轨道衡在鞍钢的应用，解决了传统动态轨道衡的一些弊端，省去了基坑，并运用计算机信息管理技术和数据采集技术构建了稳定、可靠、安全的液态称量系统，实现了列车不停车、不脱钩连续动态自动称量，提高了物流速度和管理水平。     

Relationship of Bcl-2 expression with apoptosis and proliferation in colonic graft versus host disease

OBJECTIVE: To compare hydrostatic weighing with and without head submersion and bioelectric impedance analysis (BIA) for measurement of body composition of persons who are morbidly obese. DESIGN: Body composition was determined using 3 methods: hydrostatic weighing with and without head submersion and BIA. Residual volume for the hydrostatic weighing calculation was determined by body plethysmography. SUBJECTS: Subjects were 16 morbidly obese men (142.5 kg mean body weight) and 30 morbidly obese women (125.9 kg mean body weight) living in the Salt Lake County, Utah, area. Morbid obesity was defined as 40 kg or more over ideal weight. STATISTICAL ANALYSIS: One-way, repeated-measures analysis of variance was followed by Scheffé post hoc tests; body-fat measurement method served as the repeated variable and percentage of body fat as the dependent variable. Men and women were analyzed separately. In addition, degree of agreement between the 3 methods of determining body composition was determined. A regression equation was used to calculate body density for hydrostatic weighing without head submersion. Two new BIA regression equations were developed from the data of the 16 men and 30 women. RESULTS: Values for percentage body fat from hydrostatic weighing with and without head submersion (41.8% vs 41.7%, respectively) were the same for men but differed for women (52.2% vs 49.4%, respectively, P < .0001). Values for body fat percentage measured by BIA were significantly lower for men (36.1%) and women (43.1%) (for both, P < .0001) compared with values from hydrostatic weighing methods. BIA underpredicted percentage body fat by a mean of 5.7% in men and 9.1% in women compared with the traditional hydrostatic weighing method. APPLICATIONS/CONCLUSIONS: BIA tended to underpredict the measurement of percentage body fat in male and female subjects who were morbidly obese. Hydrostatic weighing without head submersion provides an accurate, acceptable, and convenient alternative method for body composition assessment of the morbidly obese population in comparison with the traditional hydrostatic weighing method. In population screening or other settings where underwater weighing is impractical, population-specific BIA regression equations should be used because general BIA equations lead to consistent underprediction of percentage body fat compared with hydrostatic weighing.     

合金称重系统的多任务数据通信及管理

介绍了称重系统实时显示重量和多任务数据通信的可编程控制，以及PLC与上位机通信的实现方法。用该方法研制的程序已经用于宝钢炼钢厂合金称重系统，生产运行证明其达到了设计的要求。     

ICP-AES法测定金饰品中铜、铁、锌含量的不确定度评定

采用湿法消解样品, 建立电感耦合等离子体发射光谱（ICP-AES）测定黄金饰品中铜、铁和锌元素含量的方法。该方法具有简便、快速、灵敏度高及重现性好等优点。根据测量原理，建立了该方法的定量数学模型并推导出不确定度计算公式，找出了该检测过程中的不确定度来源，对各不确定度分量进行了合成和扩展，得到了铜、铁和锌质量分数的不确定度。结果表明：标准溶液的配制、标准曲线拟合线性方程及重复测量是不确定度的主要来源，黄金饰品中铜、铁和锌的质量分数可分别表示为（10.42±1.54）、（10.79± 1.21）和（26.89±1.88） mg/kg。     

汽车轻量化用钢的新思路——低密度钢板

介绍了汽车轻量化用钢的一种新思路,即通过提高钢板中Al含量,降低钢板密度,减轻钢板重量,实现汽车轻量化.同时,对不同高Al含量钢板的生产工艺和产品性能进行了分析.     

Assessment of fat-mass loss during weight reduction in obese women

Methods for assessing body fat mass (FM) loss were compared in 32 obese (body mass index [BMI], 29 to 41 kg/m2) premenopausal women before and after a weight loss of 13.0 +/- 3.4 kg (mean +/- SD). A four-component (4C) model was used as the criterion. The other methods were as follows: three-component models (body density with total body water [3W] or bone minerals [3M]), underwater weighing, dual-energy x-ray absorptiometry ([DXA] XR-26, software 2.5.2; Norland, Ft Atkinson, WI), bioelectric impedance analysis (BIA) with an obese-specific equation [Segal et al), skinfolds (Durnin and Womersley), and an equation with BMI (Deurenberg et al). The 3W model (bias +/- SD, 0.5 +/- 0.4 kg), XR-26 (0.6 +/- 2.1 kg), and BMI equation (-0.3 +/- 2.1 kg) gave practically unbiased mean estimations of fat loss. All other methods underestimated fat loss by at least 1.6 kg (range of bias, -2.7 to -1.6 kg). The small bias (0.7 +/- 1.0 kg) between underwater weighing and model 4C before weight reduction indicates that the two-component assumptions were valid in premenopausal, weight-stable obese women. However, particularly the water fraction of the fat-free body component (4C model) was increased after weight reduction (before, 72.9% +/- 1.4%; after, 75.7% +/- 2.2%), making both underwater weighing and the 3M model uncertain for assessment of body composition changes. A general tendency for overestimating FM was seen before and more clearly after weight reduction. However, most methods underestimated fat loss, apparently because of unexpected changes in hydration of the fat-free body component.     

Weight suppression and weight rebound in ex-smokers treated with fluoxetine.

Fluoxetine's effect (30 mg, 60 mg, and placebo) on postcessation weight gain was studied among participants from a randomized, double-blind 10-week smoking cessation trial who met strict criteria for abstinence and drug levels. It was hypothesized that (a) fluoxetine would dose-dependently suppress postcessation weight gain and (b) drug discontinuation would produce dose-dependent weight rebound. During the on-drug phase, placebo participants gained weight linearly (M?=?2.61 kg), exceeding both fluoxetine groups (30-mg M?=?1.33 kg, 60-mg M?=?1.25 kg). Weight suppression was initially greater for 60 mg than 30 mg, but both were followed by weight gain. Six months off-drug produced greater dose-dependent weight rebound for 60 mg than 30 mg or placebo. Considering both on- and off-drug phases, weight gain for 60 mg of fluoxetine (M?=?6.5 kg) was comparable with that for placebo (M?=?4.7 kg) but greater than that for 30 mg (M?=?3.6 kg). Fluoxetine appears to forestall postcessation weight gain, allowing time for the weight-conscious smoker to focus on quitting smoking rather than on preventing weight gain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological effects of weight loss and regain: A prospective evaluation.

This study prospectively assessed the psychological effects of weight loss and regain (i.e., weight cycling) in obese women. Measures of mood, binge eating, restraint, disinhibition, and hunger were obtained from 55 participants at baseline, after 6 months of treatment, and 58 months posttreatment. Women lost 21.1 ± 8.4 kg after 6 months of treatment but were 3.6 ± 10.9 kg above baseline weight at the time of the follow-up. Contrary to expectations, after this 21-kg cycle of weight loss and regain, women reported significant improvements in mood and binge eating, as well as reductions in hunger and disinhibition. Restraint was unchanged from baseline to follow-up. These data suggest that weight loss and regain are not associated with long-term adverse psychological effects. The findings also confirm earlier reports of significant weight regain after treatment and underscore the need for research to improve the maintenance of weight loss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

合金自动称量技术在转炉炼钢中的应用

介绍了120t转炉炼钢合金料自动称量控制系统的结构设计、编程、数据处理方法,分析了强振速度、弱振速度、弱振值、落差值等参数对称量精度的影响。该系统运用MB 通讯技术实现称量值反馈,可以完成几种合金料连续称量过程。使用证明,系统称量误差控制在了1kg之内。