Lateral extrusion of a cross fitting with a lost core

Purpose: Lateral extrusion process with a lost core for cross fittings is suggested. At first, cavity of tube is filled up by low temperature melting melting alloy. Then low temperature melting material is solidified to be the ‘lost core.’ The third, the material is extruded for lateral direction to be a cross-fittings. After deformation, low temperature melting alloy is melted and removed. The authors discuss its deform mechanism in this paper. Design/methodology/approach: Experiments and numerical analysis with ANSYS9.0. Findings: Extrusion defect is caused at the center of the cross on the inner wall of the pipe because of volume constancy when the branch diameter close to the initial pipe diameter. In such the case, contact between pipe and die surface is unstable and the branch part is not stretched enough, then it causes wrinkles. In such the case, it is better to provide more pressure against the head of branch projection. Research limitations/implications: The effect of the relationship amongst mechanical properties of the pipe and lost core is to be examined in future. We must seek better material for the lost core that is cheaper, easier to remove, clean and safer for the man and environment. Practical implications: This methodology is suitable for production of the hollow products having constant sections for lateral direction. Originality/value: The above result helps the economical production of hollow products with simple equipments.