高炉炉墙结构热应力分析
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摘要
高炉长寿已经成为当代炼铁技术进步的重要标志和组成部分。为了提高生产力,降低炼铁成本,提高高炉寿命问题已经日益突出。依据我国对高炉寿命的调查结果显示,高炉耐火内衬的破损剥落以及炉壳的开裂是影响高炉寿命的决定性因素。
高炉炉缸的传热结构是耐火砖+填料(捣打层)+冷却壁+炉壳。炉墙热面与高温炉气接触,体内冷却水强制冷却,形成很大的温度梯度和很高的热负荷。结构膨胀应力和温度差应力是造成炉墙耐材料及炉壳破损的主要原因,从而炉缸的受热变形分析以及热应力计算是实现高炉长寿的必要手段。分析高炉耐火材料和炉壳的温度场和热应力场情况,对指导高炉炉墙的设计、制造和使用维护,提高高炉的使用寿命有着重大的意义。
把炉墙结构简化为轴对称模型。根据高炉炉墙传热结构中的冷却壁和炉壳的复合对流传热的传热特点,通过对水管冷却的等效折算和炉壳对流传热边界的等效置换,建立了基于大平板和长圆筒导热理论的两种一维等效简化计算方法。给出了根据冷却热流量推测内衬侵蚀位置和炉墙温度场的计算法,其计算结果与有限元数值计算结果作了对比,表明炉缸炉墙的冷却壁和炉壳复合对流换热一维等效简化计算方法具有较高精度。
根据线性热弹性力学理论,给出了平面轴对称温度分布和受内外均布压力的作用下圆筒应力和变形计算式。针对高炉炉缸组合结构受热膨胀的力学特征,考虑冷却壁以及内外填料的热和弹性变形作用并作简化,建立了炉壳纵向开裂补强前后的结构的应力和变形计算方法。同时用有限元软件ANSYS建模仿真,算例的计算结果与有限元软件的计算结果一致。高炉服役过程中内衬侵蚀不可避免,导致炉墙温度梯度变大,热应力也相应变大。在炉壳温度较高或者炉内压力比较大的情况下炉壳会进入塑性变形状态,热弹性力学已不适用。因此根据塑性力学理论,给出了平面轴对称温度分布和受内外均布压力的作用下圆筒应力和变形计算式。并且计算比较了不同炉内(?)力对高炉炉壳热应力的影响。
本课题的研究成果对提高高炉炉墙的研发设计水平以及高炉炉壳破损维修方案都具有重要的参考价值和借鉴意义。
The long life of blast furnace has been the important sign and component part of the progress of modern pudding technology. For the improving of productivity and reducing of the cost of pudding production, the problem of improving the life of blast furnace has been prominent. According as the survey of the life of BF in our country, breakage of fireproofs inner lining flake and craze of the furnace casing is one of the important factors that impacts the longevity BF.
The heat structure of blast furnace hearth is composed of refractory bricks and filling material and cooling stave and furnace shell. The heat surface of the blast furnace wall contacts high temperature furnace gas and is cooled by cooling water, so it forms very high temperature gradient and heat load. And both structure swelling stress and temperature head stress is the main reason for damage occurred. So analyses of blast furnace hearth's temperature distortion and thermal stress are the indispensable instrument to realize the microbial of the blast furnace. Through analysis the temperature and thermal stress of the blast furnace hearth under the workplace, it can guide the cooling stave design, manufacture and use and improves the life of blast furnace hearth, and it further extends the life of blast furnace.
Furnace wall is simplied to be axisymmetric cylinder model.Though equivalent replacement of convective heat transfer boundary of water pipe surface in furnace hearth cooling stave and blast furnace shell, two simplified and equivalent method of calculating for one-dimension heat Conduction is established according to flat and plane axisymmetric cylinder heat conduct theory. It is based on the structure characteristics of the composite heat transfer of the cooling wall and the furnace shell. Method used to calculate furnace wall erosion line and temperature field of furnace wall is built. Arithmetic and example are given. It is calculated using FEM. Convective heat transfer boundary equivalent replacement and one-dimension thermal model simplification of furnace hearth cooling stave is precise.
For the thermal expansion mechanics character of blast furnace hearth wall, according to linear theory of thermal elasticity, the formula of stress and deformation are deduced while bearing axisymmetric temperature and equal pressure. And it is applied for the stress and deformation analysis of un-cracked and reinforced shell of BF hearth. ANSYS is used to be calculated. Filling material and cooling stave is thermal expansion. The stresses of shell and linings born thermal expansion and deformation of elasticity are computed, and the calculation method of shell reinforcement is given. Inner lining erosion is inevitable while the BF is in service, which results in furnace wall temperature gradient filling out as well as thermal stress. Blast furnace shell will get into plastic stress and temperature distortion, and then thermal elasticity is inapplicability. According to theory of thermal plasticity, the formula of stress and deformation are deduced while bearing axisymmetric temperature and equal pressure. Different press inside are considered to calculate the thermal stress of blast furnace shell.
These research is valuable for the design of blast furnace wall as well as disrepair of blast furnace shell.
高炉炉缸的传热结构是耐火砖+填料(捣打层)+冷却壁+炉壳。炉墙热面与高温炉气接触,体内冷却水强制冷却,形成很大的温度梯度和很高的热负荷。结构膨胀应力和温度差应力是造成炉墙耐材料及炉壳破损的主要原因,从而炉缸的受热变形分析以及热应力计算是实现高炉长寿的必要手段。分析高炉耐火材料和炉壳的温度场和热应力场情况,对指导高炉炉墙的设计、制造和使用维护,提高高炉的使用寿命有着重大的意义。
把炉墙结构简化为轴对称模型。根据高炉炉墙传热结构中的冷却壁和炉壳的复合对流传热的传热特点,通过对水管冷却的等效折算和炉壳对流传热边界的等效置换,建立了基于大平板和长圆筒导热理论的两种一维等效简化计算方法。给出了根据冷却热流量推测内衬侵蚀位置和炉墙温度场的计算法,其计算结果与有限元数值计算结果作了对比,表明炉缸炉墙的冷却壁和炉壳复合对流换热一维等效简化计算方法具有较高精度。
根据线性热弹性力学理论,给出了平面轴对称温度分布和受内外均布压力的作用下圆筒应力和变形计算式。针对高炉炉缸组合结构受热膨胀的力学特征,考虑冷却壁以及内外填料的热和弹性变形作用并作简化,建立了炉壳纵向开裂补强前后的结构的应力和变形计算方法。同时用有限元软件ANSYS建模仿真,算例的计算结果与有限元软件的计算结果一致。高炉服役过程中内衬侵蚀不可避免,导致炉墙温度梯度变大,热应力也相应变大。在炉壳温度较高或者炉内压力比较大的情况下炉壳会进入塑性变形状态,热弹性力学已不适用。因此根据塑性力学理论,给出了平面轴对称温度分布和受内外均布压力的作用下圆筒应力和变形计算式。并且计算比较了不同炉内(?)力对高炉炉壳热应力的影响。
本课题的研究成果对提高高炉炉墙的研发设计水平以及高炉炉壳破损维修方案都具有重要的参考价值和借鉴意义。
The long life of blast furnace has been the important sign and component part of the progress of modern pudding technology. For the improving of productivity and reducing of the cost of pudding production, the problem of improving the life of blast furnace has been prominent. According as the survey of the life of BF in our country, breakage of fireproofs inner lining flake and craze of the furnace casing is one of the important factors that impacts the longevity BF.
The heat structure of blast furnace hearth is composed of refractory bricks and filling material and cooling stave and furnace shell. The heat surface of the blast furnace wall contacts high temperature furnace gas and is cooled by cooling water, so it forms very high temperature gradient and heat load. And both structure swelling stress and temperature head stress is the main reason for damage occurred. So analyses of blast furnace hearth's temperature distortion and thermal stress are the indispensable instrument to realize the microbial of the blast furnace. Through analysis the temperature and thermal stress of the blast furnace hearth under the workplace, it can guide the cooling stave design, manufacture and use and improves the life of blast furnace hearth, and it further extends the life of blast furnace.
Furnace wall is simplied to be axisymmetric cylinder model.Though equivalent replacement of convective heat transfer boundary of water pipe surface in furnace hearth cooling stave and blast furnace shell, two simplified and equivalent method of calculating for one-dimension heat Conduction is established according to flat and plane axisymmetric cylinder heat conduct theory. It is based on the structure characteristics of the composite heat transfer of the cooling wall and the furnace shell. Method used to calculate furnace wall erosion line and temperature field of furnace wall is built. Arithmetic and example are given. It is calculated using FEM. Convective heat transfer boundary equivalent replacement and one-dimension thermal model simplification of furnace hearth cooling stave is precise.
For the thermal expansion mechanics character of blast furnace hearth wall, according to linear theory of thermal elasticity, the formula of stress and deformation are deduced while bearing axisymmetric temperature and equal pressure. And it is applied for the stress and deformation analysis of un-cracked and reinforced shell of BF hearth. ANSYS is used to be calculated. Filling material and cooling stave is thermal expansion. The stresses of shell and linings born thermal expansion and deformation of elasticity are computed, and the calculation method of shell reinforcement is given. Inner lining erosion is inevitable while the BF is in service, which results in furnace wall temperature gradient filling out as well as thermal stress. Blast furnace shell will get into plastic stress and temperature distortion, and then thermal elasticity is inapplicability. According to theory of thermal plasticity, the formula of stress and deformation are deduced while bearing axisymmetric temperature and equal pressure. Different press inside are considered to calculate the thermal stress of blast furnace shell.
These research is valuable for the design of blast furnace wall as well as disrepair of blast furnace shell.
引文
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3.陈宝剑,靳星亮.7号高炉冷却壁破损原因初探[J],山西冶金,2000,(3)：11-12,17.
4.曹传根,周渝生,叶正才.宝钢3号高炉冷却壁破损的原因及防止对策,炼铁,2000,19(2)：1-5.
5. Murlis, J. Optimization of the blast furnace profile for blast furnace smelting under various conditions [J], Journal of Engineering and Applied Science,1996,37(1): 45.
6.周强.高效长寿高炉的冷却设备,铜冷却壁[J],炼铁,2001,20(3)：12-16.
7. Desai B, Lenka S. Quantification of blast furnace hearth drainage parameters through physical model study [J]. Ironmaking and Steelmaking,2007, 34(3):269-271.
8.徐矩良.延长高炉寿命的途径[J],鞍钢技术,1995(2)：4-7.
9.胡源申,袁晓敏,王彪等.高炉HT与QT冷却壁解剖及破损行为比较研究[J],包头钢铁学院学报,1999,18(3)：187-193.
10.宋阳升.世界炼铁技术发展的回顾和展望[J],炼铁,1998,17(4)：1-9.
11.汪学峰等.关于大中型长寿高炉设计[J],炼铁,1996,15(3).
12.万新,高艳宏,吴明全.炼铁设备及车间设计[M],北京：冶金工业出版社,2007,33-35.
13.程素森,杨天均,杨为国,全强,吴启常.高炉铜冷却壁分析[J],钢铁,2001,36(2).
14.杨尚宝,杨天均,窦庆和,聂世锋,崔六喜,南祥民.高炉炉衬破损调查与炉体状态模型的建立[J],钢铁,1998,33(6).
15.项钟庸.高炉炉体冷却技术的进步[J],宝钢技术,1994,11(4)：1-5.
16.小山保二郎.高炉炉身下部炉衬损伤机理的分析和对策[J].日本钢管情报,1982,92：1-15.
17.顾飞,姚家瑜.我国高炉冷却水调查及评价[J],炼铁,1996,(4)：10.18.刘华.天铁高炉镶砖冷却壁的破损分析及预防措施[J],炼铁,1998,17(4)：28-31.
19. Rumelhart.D.E, Mcclelland.T.L. PDP Research Group Paralel Distributed Processing, Cambridge Mass, MIT Press [M],1986.
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