带装钢机和出钢机的线棒材加热炉的设计思考

以某钢厂加热炉建设为背景,从平面布置、设备结构及动作时序入手,对带有装钢机和出钢机的线棒材加热炉的设计要点进行了介绍,为类似项目的设计提供参考。     

连续式轧钢加热炉在线控制数学模型与应用

以理论计算和实测数据为依据,开发了连续式加热炉最佳炉温设定和在线控制数学模型,并应用于安钢中型厂5点供热推钢式加热炉。结果表明：在轧机产量波动时,不但加热炉供热合理,而且钢温波动小、加热质量好、节能效果显著。     

小型轧钢加热炉技术改造

本文介绍了１９９５年初，对小型加热炉进行改造，增加风机并联，并把原两个喷咀换型，预热段滑道由无水冷改为水冷，头炉炉底增加一个水冷出钢槽，改造后，产量增加，吨钢油耗降低，经济效益显著。     

无水冷技术在小型轧机加热炉的应用

重庆长江钢厂为了提高加热炉的热效率,节约能源,消除钢坯在水冷出钢槽上产生的阴阳面和在水冷炉筋管滑轨上产生的墨印,减少轧制事故,提高产品质量,避免汽化冷却装置因意外事故(如冷却水管堵塞或人为因素等引起冷却水断流),造成炉筋管和出钢槽产生弯曲变形引起停产,于1990年起对φ350×1/φ250×6轧机加热炉进行技术改造,采用了莫来石出钢槽和无水冷滑轨等新技术,取消了加热炉的水冷系统(包括汽化冷却装置),实现了无水冷加热,取得了较好的经济效益。     

加热炉燃料消耗偏高的原因分析及降耗措施

分析了攀钢线材厂加热炉吨钢燃耗偏高的原因;通过采取优化钢坯加热温度、优化加热炉待轧保温制度、提高热风预热温度和规范燃烧控制等一系列措施,使加热炉吨钢燃耗得到了明显降低。     

首钢中小型厂加热炉设计

首钢中小型厂加热炉设计首钢设计总院工业炉室王汝芳，刘学民，王丰首钢中小型厂由两个棒材车间组成，总的年生产能力为１５０万吨，为满足工艺生产要求，两车间各新配备了一座推钢式加热炉，每座炉子的小时产量均为１６０吨。一、炉型结构特点１．装出料方式加热炉装料有...     

采用新技术 科学管理 成绩显著

柳钢中板厂是1975年建成投产的,轧机为2300mm×3三辊劳特式轧机。当时只有1＃加热炉,轧制扁锭,由于原材料供应不足和其它一些原因,年产量才3万多吨;到1980年增建2＃加热炉,轧转炉连铸坯,产量才逐渐提高。特别是近几年,实际产量均超过设计水平,达30多万吨。该厂现有两座加热炉,都是推钢式连续加热炉,炉底有效面积为24.244×3.596=87m~2。     

采用破号装炉工艺节能降耗提高效益

<正> 一、传统装炉工艺济钢中板分厂在1988年技术改造以前有两座三段推钢式加热炉,燃料为重油。装炉工艺是两座加热炉同时生产时,将每个批号的坯料装在一座加热炉内,出完一个批号后再从另一座加热炉出另一个批号。每个批号最大允许装炉量为60t,30～40块组成一个批号。每个批号的钢种加热条件相同,温度一致性好,而且     

热装加热炉热工制度的研究

利用炉内钢坯加热过程的数学模型及热平衡模型,依据加热炉不同产量和不同热装温度条件下,对热装加热炉的钢坯加热过程和燃料消耗进行了数值模拟和优化.结果表明,热装加热炉的热工制度如不作调整,物料热装带来的节能潜力得不到充分发挥,调整后的加热炉温度制度将具有最大的节能潜力.     

具有特殊功能的三种加热炉用出钢机设计

根据现场条件设计了拉料式出钢机和倾翻式出钢机,使坯料自动进入轧线进行轧制,同时保证了后续的坯料在炉内均温区内,实现了自动化、连续式生产。在步进梁式加热炉内带垫板加热薄板,出炉后将垫板和薄板快速分离难度很大,文中提供了一种组合式去垫板出钢机。这三种特殊功能的出钢机方案,作为实例为设计工作者提供了更多的设计思路,对解决实际技改问题有一定的借鉴意义。     

交流电晕放电下SF6气体分解物的光谱检测

随着GIS等SF6气体绝缘设备的大规模使用,探索SF6气体的分解机理对延长设备寿命并确保其安全运行有重要的理论指导和现实意义.探讨GIS中典型放电性故障特征及相应的SF6气体分解产物和分解机理,给出了不同放电类型故障相关试验结果,并对最常见的电晕放电故障给出了放电量与分解产物的关系.在此基础上,设计了满足试验要求的气体放电装置,放电量检测单元和SF6气体分解产物检测系统,研究了交流电晕放电下主要气体分解产物及其增长规律,探讨了主要气体分解产物的生成机理.通过与已有文献比较,验证了试验结果的准确性.     

惠炼延迟焦化焦炭塔顺控系统的调试与运行

延迟焦化装置控制复杂,操作人员劳动强度大、时间长、环境较差,为避免人为误操作事故的发生,保障人员和设备的安全,中国海油惠州炼油分公司4200kt/a采用"两炉四塔"工艺的延迟焦化装置共投用了两套安全仪表系统(SIS)系统。SIS系统可对生产装置可能发生的危险或不采取措施将继续恶化的状态及时响应和进行保护,使生产装置进入一个预定义的安全停车工况,从而使危险降低到最低程度,以保证人员、设备与装置的安全。介绍了焦炭塔顺控系统的选型、组成与特点、测试方法;分析了顺控系统测试与运行中出现的主要问题,实施了整改方案,包括:将所有输入信号412点增加旁路,DCS画面增加切除按钮,各参数条件放宽,各步骤设定时间缩短等。6个月的运行表明,惠炼延迟焦化装置焦炭塔顺控方案运行良好,为焦炭塔的安全长周期生产提供了保障。     

Enrichment of heat transfer in a latent heat storage unit using longitudinal fins

The charging and discharging rates of a phase change material (PCM) in a horizontal latent heat storage unit (LHSU) is largely influenced by the lower thermal conductivity of the PCM. In the present research, four different configurations of longitudinal fins are proposed to augment the heat transfer in horizontal shell and tube type LHSUs. Numerical investigations are reported to establish the thermal performance augmentation with rectangular, triangular, and Y‐shaped (bifurcated) fins. From the results, it has been inferred that all fin configurations provide a faster charging and discharging rate. In the present set of geometric dimensions of LHSU considered, a reduction in charging time of 68.71% is evaluated for case III (three rectangular fins with one fin positioned in the area of the heat transfer fluid [HTF] surface) and case V (two bifurcated fins with one fin positioned in the area of the HTF surface). Moreover, overall cycle (charging + discharging) time is reduced by 58.3% for case III. Employment of fins results in a faster rate of absorption and extraction of energy from the PCM.     

水电站溢洪道泄槽温度场和温度应力有限元分析

通过3种方案：无寒潮、有寒潮无保护、有寒潮有保护情况．对某水电站溢洪道泄槽施工期温度场及温度应力进行了三维有限元仿真计算,研究了寒潮对溢洪道泄槽的影响范围及寒潮引起的温度场和温度应力的分布规律,对比了无保护和有保护情况下典型点的温度应力及不同厚度泡沫板的保温效果,提出了避免产生表面裂缝的保护措施,为泄槽的工程施工提供参考依据。     

The behaviour of adsorbent energy storage beds

A numerical study is made of the behaviour of packed beds containing adsorbent material used for energy storage.The basic model assumes that air at a given absolute humidity and at either a high or low temperature is available to charge or discharge the store, the air flow direction for the charging case being opposed to that for the discharging case. When air flows through the bed, transfer of heat and water vapour to the air stream is assumed to teh governed by surface transfer coefficients, while difusion of heat and water vapour in the fluid flow direction is neglected. For periods of no air flow, diffusion in the direction of the bed axis occurs; and for both the air flow and no air flow cases, heat transfer through the container walls is included.From the foregoing, three operating modes are possible—charging, discharging and no flow—and when charging or discharging there may be variations in the air flow rate. A repeatable random number sequence is used to determine the mode of operation at each time step during the numerical integration, and the magnitude of the random number determines the air flow rate.For this random number sequence the effects of wall losses and adsorption capacity of the adsorbent (on store performance) are studied.     

机械冷板冷藏车充放冷影响因素分析

机械冷板冷藏车充冷需要大量冷量，而放冷过程中存在放冷不充分的现象，冷板内共晶溶液蓄存冷量不能充分利用，造成冷量浪费。本文建立了冷板冷藏车的充放冷模型，对影响冷板充放冷的因素进行了分析，研究了不同种类、质量、过冷温度下共晶溶液的充放冷情况，指出可以根据需冷量对冷板进行部分充冷，既节约充冷量，又能保证冷板冷量得到充分利用；共晶冰过冷延长了充冷时间，增加了充冷能耗．而且降低了冷量的有效利用率。     

Simulation and evaluation of stratified discharging and charging devices in combined solar thermal systems

This simulation study investigates different discharging and charging strategies and their effects on the performance of a combined solar thermal system in a single family house. Based on the system according to Task 32 of the Solar Heating and Cooling Program of the International Energy Agency (IEA SHC) the system layout and in specific the storage connections are modified to investigate different stratified charging and discharging concepts realized by external valves or devices within the storage tank.A broad literature overview shows that a comprehensive comparison of charging and discharging strategies under the same boundary conditions and after optimization of the storage connection heights is not available.The results of this study show that a good thermal stratification within the storage and thus higher energy savings can be reached by both a stratified charging and discharging. Depending on the system size and the design of charging and discharging connections the stratified discharging leads to the same or even higher energy savings than a stratified charging. Already one single four-way mixing valve in the space heating flow (i.e. two tapping points) leads on the one hand to more than 80% of the advantage of an idealized discharging with seven tapping points, and on the other hand in all cases to significantly higher energy savings if compared to two charging devices with three-way valves. The relative energy savings increase with increasing solar fraction, e.g. with larger dimensions and better insulated buildings.The best option with the highest benefit depends on the system design like storage in- and outlet positions, system size and load conditions. Therefore, the decision for the best suited strategy can only be determined by simulations representing the respective system. The results presented in this paper, however, allow deriving general dependencies.     

Optimization of the preventive maintenance plan of a series components system

One of the most critical problems in preventive maintenance is the determination of the optimum frequency to perform preventive maintenance in equipment, in order to ensure its availability. In this paper, we propose an algorithm to solve the previous problem for equipment that exhibit linearly increasing hazard rate and constant repair rate. Based on this algorithm, we have developed another one to solve the problem of maintenance management of a series system based on preventive maintenance over the different system components. We assume that all components of the system still exhibit linearly increasing hazard rate and constant repair rate and that preventive maintenance would bring the system to the as good as new condition. We define a cost function for maintenance tasks (preventive and corrective) for the system. The algorithm calculates the interval of time between preventive maintenance actions for each component, minimizing the costs, and in such a way that the total downtime, in a certain period of time, does not exceed a predetermined value.     

Experimental Investigation on Heat Storage/Retrieval Characteristics of a Latent Heat Storage System

The charging and discharging characteristics of a latent thermal energy storage (LTES) system were experimentally studied. Pure paraffin and paraffin/expanded graphite (EG) composite containing 7% and 10% mass fraction of EG were used as the phase-change materials (PCMs). Various experiments were conducted with different heat transfer fluid (HTF) temperatures and flow rates for heat storage and retrieval, respectively. The time durations of the charging and discharging processes, the mean power, and the energy efficiency of the system, which are the important factors of the LTES system, were discussed. The results showed that natural convection played a crucial role in the heat transfer during the charging process of paraffin, but heat conduction was the main heat transfer mechanism during the discharging process of paraffin. The higher the flow rate was, the higher the charging and discharging rate would be. Large temperature difference between the HTF and the initial state of PCM would accelerate the charging and discharging processes. During the charging process, the large temperature difference would result in the accelerated phase-change process due to the enhanced natural convection that could be seen clearly when the PCM was paraffin. While no significant difference was found for different initial temperatures during the discharging process. The performance of the LTES was affected prominently by the PCMs, HTF temperatures, and flow rates. The energy efficiency was higher for the 10 wt% EG PCMs, and the mean power during the discharging process was larger accordingly.