Abstract: Shear-extrusion process and its forming parameters are proposed, whilst its laborsae ing characteristic is utilized to forge large-size shutoff valve body on middle-due pre ss.This new process is intended for the manufacture of large-size forged tubular components with branches on middle-due press. Experiments are carried out and proeessing parameters are obtained regarding the shear-extrusion process of a large-size shutoff valve body. Deformation and metal flow in the shear-extrnsion process are investigated. In order to verify the laborsaving characteristic of this new procss some contrastive experiments of extrusion foree are performed between shear-extrusion and upsetting-extrusion for forming tubular components with branches. Based on rigidplastic FEM a plane-strain model is established to analyze shear-extrusion process of tubular components with branches. The analysis results by 2-dimensions FEM are comparatively quite well consistent with those of experiments. Both simulated anl etperimental results show that this new forming process is feasible for forging large-size tubular components with branches on middle-due press.

Key words: tubular component with branch, shear-extrusion, FEM