The quality and accuracy of pipes produced by modern pipe-rolling plants are mainly dependent on the quality of the shells produced by piercing mills. Therefore, in designing rolling tool, followed by setting up a piercing mill, it is necessary to ensure that shells produced are of high accuracy and quality. To this end, the effect of changes in the parameters of the deformation zone and the boundary conditions on the piercing process should be taken into account. The deformation zone of a piercing mill and its main sections are considered. The effect of change in each parameter on the dimensions of the resulting shell and on the controlled parameters of the piercing process is determined.

The accuracy of shells depends on the capability of the roll design to ensure that the angle of the sizing portion of the plug corresponds to the angle of the exit cone of the roll, taking into account the distortion of its profile due to the turn through the feed and toe angles, and the quality depends on the capability to ensure the operation in the recommended ranges of controlled parameters of the piercing process. For hard-to-deform high-alloy steels, narrower ranges of controlled parameters are used.

The effect of the type and design of the rolls of the piercing mill on the parameters of the deformation zone and the dimensions of the resulting shell is studied.

现代轧制厂生产的管材的质量和精度主要取决于穿孔机生产的管壳的质量。因此，在设计轧制工具时，随后要设置穿孔机，必须确保所生产的壳体具有高精度和高质量。为此，应考虑变形区参数和边界条件的变化对穿孔过程的影响。考虑了穿孔机的变形区及其主要部分。确定每个参数的变化对所得壳的尺寸以及对穿孔工艺的受控参数的影响。

壳的精度取决于轧辊设计的能力，以确保塞子上浆部分的角度与轧辊出口锥角相对应，同时考虑到由于转弯而导致的轮廓变形。进给角和脚趾角，质量取决于确保在穿孔工艺的受控参数的建议范围内运行的能力。对于难以变形的高合金钢，使用的控制参数范围较窄。

研究了穿孔机轧辊的类型和设计对变形区参数和最终壳尺寸的影响。