The Russian Research Institute of the Tube and Pipe Industries OJSC, Chelyabinsk, Russia:

A. V. Vydrin, Dr.Eng., Deputy General Director for Research, vydrinav@rosniti.ru

V. V. Shirokov, Engineer of Laboratory of simulation of processes

Simulation of seamless pipes production in mandrel mill is discussed. Conceptual model of tube rolling mill with continuous elongation mill is presented. Mathematical relationships and calculation algorithm based on energy-power method for calculating of power rate and speed mode are declared. Influence of tension level on the range of variation of tube wall thickness with nominal thickness 6.45 mm and 7.2 mm is shown. Number of tubes from 1526 (26G2) and 4125 (25 KhM) steels was 12 and 10 in the batches with a.m. wall thickness respectively. It was concluded that increase of interstand tension leads to improvement of tube precision in wall thickness. Distribution of longitudinal stresses in interstand space is displayed; its average value showed deviation not more than 4 %. It testified that the developed technique for calculation of interstand tension allows to receive reliable qualitative results. Scheme of action of forces applied to the deformation area in tube rolling on a long cylindric mandrel is observed. The obtained technique can be used in development of speed conditions for continuous mill with 2-high stands, providing preset of interstand tension; for indirect determination of interstand tensions for preset speed conditions; as well as for estimation of mechanical properties of metallurgical equipment.