带钢连退炉均热段电热功率确定

Determination of Electric Heating Power in the Soaking Section of Strip Steel Continuous Annealing Furnace

对于冷轧带钢的热处理,一般分为加热段、均热段、冷却段等主要工艺段。对于热处理过程中的均热段,传统的加热均温方式为燃气燃烧加热,但随着国家环保政策日趋严格,冷轧带钢热处理领域中的加热技术向绿色低碳发展的需求更加迫切。因电加热技术较燃气燃烧加热更节能环保,且控制带温精准,更适合高品质带钢的均热需求,故现在冷轧带钢热处理过程中均热处理基本上转变为电加热方式,旨在满足带温的精确控制。传统的均热段电热功率设计过多地依赖于工程类比,缺乏系统的理论分析,致使均热段电热元件设计选型后,出现均热能力不能很好地匹配工程所需。均热能力不足无法达成工艺要求,均热能力过剩则会带来电能使用不经济且伴随着电热元件的投资成本增加。针对上述问题,梳理了电热元件功率选型的经验方法和存在的不足,重点提出按照热平衡原理确定电热功率设计选型方法,并推导出电热元件功率的理论公式,在此基础上,深入分析了均热段电热元件功率输出与相关影响因素之间的关系,旨在为今后均热段的设计精细化、经济化作参考。

For the heat treatment of cold-rolled strip,it is generally divided into main process stages such as heating section,soking section,and cooling section.For the soking section in the heat treatment process,the traditional heating method is gas combustion heating.However,with the increasingly strict national environmental protection policies,the demand for green and low-carbon development of heating technology in the field of cold rolled strip heat treatment is becoming more urgent.Due to the fact that electric heating technology is more energy-efficient and environmentally friendly than gas combustion heating,and has precise temperature control,it is more suitable for the homogenization needs of high-quality strip.Therefore,in the heat treatment process of cold-rolled strip,the homogenization treatment has basically changed to electric heating,aiming to meet the precise control of strip temperature.The traditional design of electric heating power in the soking section relies too much on engineering analogies and lacks systematic theoretical analysis,resulting in the inability of the soking capacity to match the engineering requirements well after the design and selection of electric heating components in the soking section.Insufficient heat sharing capacity cannot meet the process requirements,while excessive heat sharing capacity will result in uneconomical use of electrical energy and an increase in investment costs for electric heating components.In response to the above issues,this article summarizes the experience and shortcomings of power selection for electric heating elements,and focuses on proposing a design and selection method for electric heating power based on the principle of thermal balance,The theoretical formula for electric heating element power is derived,and on this basis,the relationship between the power output of electric heating elements in the soking section and related influencing factors is analyzed in depth,aiming to provide reference for the refinement and economy of design in the soking section in the future.