论文部分内容阅读
在垂直上引无芯连铸工况下,管芯内铁液静压力和管坯自重的周期性作用,消除了凝固管壳与石墨套之间的气隙,为建立凝固层增长模型创造了理想的初始边界条件。垂直连铸结晶器本身温度场的分布以及圆锥形铁液液柱蓄热量由下至上逐渐减少,抵消了凝固层由下至上逐步增厚引起的热阻增加,使得不同高度上的径向热传输量与结晶器轴向距离无关,成为常数。实验和计算表明,在所确定的各种参数条件下,拉拔过程中凝固层厚度(δ)与管壳在结晶器中停顿的时间(t)呈简单线性关系。
In the case of vertical continuous casting with no core, the periodic hydrostatic pressure in the die and the self-weight of the tube blank eliminate the air gap between the solidified shell and the graphite sleeve, which creates a model for establishing the growth model of the solidified layer Ideal initial boundary conditions. The vertical temperature continuous casting mold temperature distribution and the conical molten iron liquid column gradually reduce the heat accumulation from the bottom to counteract the solidified layer from the bottom to the top of the gradual thickening caused by increased thermal resistance, making the different levels of radial heat transfer The amount of mold axial distance has nothing to do, as a constant. Experiments and calculations show that there is a simple linear relationship between the thickness of the solidified layer (δ) and the time (t) in the mold during the process of drawing under various parameters.