本文极力避免采用前滑区和后滑区单位压力相等处为中性点的假设,根据秒流量相等原理,求出变形区金属轴向流动速度方程,然后此方程与轧辊速度方程联立,并以前滑区面积为补充方程,得到浮动芯棒以及限动芯棒轧管时的中性面的椭圆分布解析式,并做实验证实了这一分布. This article strongly avoids the assumption that the unit pressure in the front and rear sliding zones are neutral. Based on the principle of equal flow in the second, the axial flow velocity equation of the metal in the deformation zone is obtained, and then this equation is combined with the roll velocity equation Formerly, the sliding area is a supplementary equation, and the analytical solution of the elliptical distribution of the floating core rod and the neutral surface when the core rod is restrained is obtained. Experiments prove this distribution.