One way is to use a hollow billet and then use a fixed or floating mandrel.
一种方法是使用空心坯，然后使用固定或浮动芯棒。
An investigation on relevant operation has proven that compared with the pipe-rolling processes adapting fixed mandrel, floating mandrel and retained mandrel respectively, the said pull-mandrel process provides such advantages as light-wall pipe-rolling, higher geometric accuracy and better inner/outer surface quality.
探讨了拉力芯棒轧制与固定芯棒轧制、浮动芯棒轧制和限动芯棒轧制相比所显示的优越性。实践表明，采用拉力芯棒轧制方式，可以轧制薄壁管，提高产品尺寸精度和内表面质量。
To study the mechanism of production and regularities of distribution for residual stress in pipe drawing with fixed mandrel, the drawing process was investigated by elastic-plastic FEM.
为了研究固定短芯棒拔管残余应力的产生机理和分布规律，采用弹塑性有限元法模拟拉拔过程，讨论模具形状参数、拉拔变形参数、摩擦条件对残余应力的影响。
The maximum height of wrinkling wave does not almost alter with the increase of the initial lead of the mandrel when the initial lead reached a fixed value.
当芯棒伸出量达到一定值后，随着芯棒伸出量的增大，起皱波纹高度极大值变化不明显。