RusNITI JSC (Chelyabinsk, Russia):

A. V. Vydrin, Dr. Eng., Prof., Deputy General Director for Research, e-mail: VydrinAV@rosniti.ru

South Ural State University (Chelyabinsk, Russia):
D. A. Akhmerov, Postgraduate Student, Dept. of Processes and Machines for Metal Forming, Junior Researcher, Laboratory for Modeling Technological Processes, e-mail: AhmerovDA@rosniti.ru

Scientific and Technical center TMK Ltd. (TMK NTTs) (Moscow, Russia):
E. V. Khramkov, Deputy Head of the Laboratory for Digitalization of Technologies

The paper deals with issues related to longitudinal stresses when rolling pipes on a three-roll reduction-stretching mill. The article presents a simulation model of the pipe reduction process to determine the longitudinal forces arising in the pipe string between the working stands of a continuous tension reduction mill. An algorithm for calculating a simulation model is presented, which makes it possible to calculate the stress from the front and rear longitudinal forces. The algorithm is based on determining the value of the second volume as the product of the crosssectional area of the pipe string coming out of the reduction mill by the average roll speed of the last stand along the groove perimeter. This model was used to calculate the pulling capacity of the rolls in each stand, i.e., what are the maximum possible longitudinal forces they can create in the pipe sections between the stands. The influence of the number of rotation of the rolls in the last group of influence on the longitudinal forces is shown. With the help of a computer, the reliability of the model was assessed.

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