Print Depth Prediction in Hot Forming Process with a Reconfigurable Die
Hydro power industry uses hot forming processes of thick steel plates for the forming of components such as blades, crowns and bands of Francis runners. A reconfigurable discrete die could reduce the cost and the process time of the pressing of plates when compared to the current methods where a die is machined to the shape of the part. The proposed reconfigurable die is made of an array of pins with spherical tip. The height of each pin is adjustable and can be set to produce different parts in a Francis runner (crown sector, band sector or blade). That type of die can eliminate the need of machining a new surface for each new shape to press. In this paper finite element analysis is used to simulate the hot forming process of a part for a Francis runner with a reconfigurable discrete die. The goal of the analysis is to develop a representative model of the effect of tip radius of each pin, on the depth of the pin prints left on the part and on the required pressing force. The model must be valuable for parts of different thicknesses.