QFORM-based research how the accuracy settings of piercing mill centering units axis influences hollow shell thickness

Seamless pipes are a type of rolled metal, the production technology of which provides for the absence of any seams along the entire length of the products. These solid blanks are made on special rolling machines. The production of seamless pipes is a complex process that requires compliance with all technical standards. In the current practice in the production of seamless pipes, special attention is paid to the conformity of the resulting products. Moreover, the more accurate the resulting pipe, the easier it is to carry out subsequent operations such as threading, end upsetting, etc. One of the ways to increase the accuracy of the pipes being produced is the accuracy of alignment of the centering axes that hold the mandrel relative to the axis of the blank piercing on the piercing mill, as well as the accuracy of aligning the axis on the rolling mill. This article discusses the effect of adjusting the centering axes on the geometry of the workpiece, namely on the thickness difference. As a result of the work, 3D models of the elements of the piercing mill and the workpiece itself were built in the SolidWorks software and positioned relative to each other, computer modeling of the piercing process was carried out in the QForm 2D/3D software environment with different values of the deviation of the centering axes from the piercing axis: 0 mm, 2 mm, 5 mm. After obtaining data on the geometry of the workpiece, the necessary graphs were built and a comparative analysis of the data obtained was performed. The regularities of the influence of the deviation of the centering axes from the piercing axis were revealed and a conclusion was made about the permissible deviation at which the workpiece would receive the necessary thickness variation.