Estimation of the accuracy of the formation of the ends of pipes during calibration

The main purpose of casing strings is to reinforce the well, ensure its tightness and contain soil pressure. At the ends of such pipes, threading is carried out that meets the tightness, for example, such as a premium connection TMK UP FMC. In this regard, increased requirements are imposed on the casing pipe both in terms of pipe ends and mechanical properties. To ensure good quality threading, pipe ends must be prepared, for example using end sizing presses. Currently, in the practice of sizing the ends, various methods are used, such as: distribution with an inner ring (punch), compression with an outer ring, joint use of an inner and outer ring, and a conical punch can also be used. Different calibration schemes are used depending on the type of tool used and the original pipe geometry. As a result of the work, the simulation in the QForm 3D environment of various strategies for calibrating pipe ends was carried out to determine the effectiveness of using various methods for calibrating pipe ends: strategy A - sequential shaping of pipe ends using a punch, outer and conical rings; strategy B - joint use of the punch and outer ring with subsequent conical calibration; strategy C - sequential shaping of the ends of the pipes using a punch and an outer ring, followed by conical calibration; strategy D - shape change of pipe ends only with a tapered ring.