"RIV/26316919:_____/11:#0000306" . . . "RIV/26316919:_____/11:#0000306!RIV12-MPO-26316919" . "199497" . . . "Weinheim, Germany" . "1"^^ . "[6EC887E41A22]" . "Wiley-VCH Verlag GmbH & Co." . . "FEM-modelling of Barrel-type Cross-roll Piercing and Analysis of the Induced Rotational Motion of the Plug Bar" . "10th International Conference on The Technology of Plasticity, ICTP 2011, Special Edition" . . "2011-08-25+02:00"^^ . "2"^^ . . . "Zemko, Michal" . . "Essential for the manufacturing of seamless precision steel tubes is the knowledge of the entire process chain. In regard to the cross-roll piercing procedure, the aim is to accurately predict material flow and resulting mechanical and geometrical properties of the tubular hollow. The plug guides the material flow and rotates due to friction in contact zones with the billet material. Because of elastic deflections of the rotating plug bar, the behaviour of plug bar and plug does significantly influence the billet deformation. A gap of knowledge exists about the induced motion of the plug and, as a consequence, about the influence of its motion on the resulting properties of the tubular hollow. To simulate material flow and elastic deflections of the plug bar, a finite element model was developed using FEM-software DEFORM. Different fracture models to simulate the fracture evolution due to the Mannesmann efect were compared. Simulations without plug, and with rigid plug and plug bar, and finally simulations with elastic plug and plug bar were analysed. A modified approach of %22Normalized Cockcroft-Latham%22 criterion was used for modelling of fracture evolution. The FEM-simulation indicates the material flow with characteristic helical paths concurrent with oscillating elastic deflections of the plug bar and orbital, rotational motion of the plug."@en . "FEM-modelling of Barrel-type Cross-roll Piercing and Analysis of the Induced Rotational Motion of the Plug Bar" . . "FEM-modelling of Barrel-type Cross-roll Piercing and Analysis of the Induced Rotational Motion of the Plug Bar"@en . . "N" . . "Essential for the manufacturing of seamless precision steel tubes is the knowledge of the entire process chain. In regard to the cross-roll piercing procedure, the aim is to accurately predict material flow and resulting mechanical and geometrical properties of the tubular hollow. The plug guides the material flow and rotates due to friction in contact zones with the billet material. Because of elastic deflections of the rotating plug bar, the behaviour of plug bar and plug does significantly influence the billet deformation. A gap of knowledge exists about the induced motion of the plug and, as a consequence, about the influence of its motion on the resulting properties of the tubular hollow. To simulate material flow and elastic deflections of the plug bar, a finite element model was developed using FEM-software DEFORM. Different fracture models to simulate the fracture evolution due to the Mannesmann efect were compared. Simulations without plug, and with rigid plug and plug bar, and finally simulations with elastic plug and plug bar were analysed. A modified approach of %22Normalized Cockcroft-Latham%22 criterion was used for modelling of fracture evolution. The FEM-simulation indicates the material flow with characteristic helical paths concurrent with oscillating elastic deflections of the plug bar and orbital, rotational motion of the plug." . . "FEM-modelling of Barrel-type Cross-roll Piercing and Analysis of the Induced Rotational Motion of the Plug Bar"@en . "6"^^ . "978-3-514-00784-0" . . . . "Bulk forming, Tube rolling, Cross-roll piercing, Fracture modelling, Finite element model"@en . "Aachen, germany" . . .