Abstract

The circular multi-point forming (CMPF) is a flexible technique in which the fixed shape of conventional dies is replaced by two matrices of moveable punch elements called upper and lower punch grope. This paper focuses on design, simulation and manufacture of circular multi point die to produce several forms of product by using one die. This die designed by Auto cad program, and third degree with four control point points open uniform B-spline approximation technique was adopted to represent the bending surface by using MATLAB software program. The coordinate of each point of surface taken from this program to create the by adjusting the height of each punch manually. Finite element method software (ANSYS 15) was used to simulate the circular forming process numerically and due to symmetry of product only one quarter surface of circular MPD was simulated. Aluminum 1070 plate with 1mm thickness has been chosen. The effect of (1,3,5 kN) blank holder force and (17*17, 25*25) number of pins has been studied numerically in term of stress and strain distribution and thickness variation. The experimental work involved manufacturing circular MPD and forming required product by insertion and absence of (2 mm) rubber to show the effect of interpolator on dimpling and thickness variation along the sheet metal. The results showed that the insertion of (2 mm) rubber interpolator and (3 kN) blank holder force is the best to avoid the dimpling, wrinkling defect and give good stress, strain distribution and thickness variation.