摘要
焊接具有磁性的管道焊口时,焊口剩磁产生的磁场和焊接电弧产生的磁场组成复合磁场,若复合磁场的洛伦兹力大于电磁场的收缩力,焊接电弧带电粒子的运动角度发生偏转,在宏观上表现为电弧偏吹,即磁偏吹。若电弧的偏转角度大于45o,在焊接过程中将出现严重的磁偏吹现象,反之,磁偏吹现象不明显。利用有限元软件ANSYS对管道、消磁线圈以及外部空气进行实体建模,通过对模型简化和求解,得到消磁磁场的分布情况:磁场以通电螺线管的轴线为对称轴呈对称分布,且线圈中心的磁场强度最弱,距离线圈无限远处的磁场强度为0;沿径向两端管壁的磁场强度最大,无限远处的磁场强度为0,中间区域分布较均匀。对长输管道直流消磁方法进行优化,介绍了直流消磁方法的两种基本形式。
When welding pipes with residual magnetism, magnetic field caused by the residual magnetism and magnetic field caused by welding arc compose compound magnetic field. If Lorentz force of the compound magnetic field is bigger than contractile force of electromagnetic field, a magnetic blow phenomenon occurs. If the deflection angle of welding arc is more than 45°, welding processes appear serious phenomena of magnetic blow. In this paper, ANSYS software was used to establish solid model for finite element analysis of pipelines and degaussing coil, and through simplifying the model, distribution of the degaussing magnetic field was gained. DC degaussing method of long distance pipelines was optimized, and two basic ways of DC degaussing method were introduced.
出处
《当代化工》
CAS
2012年第11期1255-1258,共4页
Contemporary Chemical Industry
关键词
长输管道
剩磁
消磁
磁偏吹
复合磁场
ANSYS模拟
Long distance pipeline
Residual magnetism
Degaussing
magnetic blow
Compound magnetic field
ANSYS simulation
