A deep drawing operation is performed in which the inside of the cylindrical cup has a diameter = 4.0 inches and a height = 2.5 inches. The stock thickness = 1/8 inch, and the starting blank diameter = 7.5 inches. Punch and die radii = 5/32 inch. The metal has a tensile strength = 60,000 Ib'in' and a yield strength = 30,000 lb/in". Determine: (a) drawing ratio, (b) reduction, (c) drawing force, and (d) blankholder force. %3D Upper limit on the drawing ratio is a value of 2.0 Db De Measures of Drawing DR = D Dp Should be less than 0.50. Reduction r, r =- Db DP 0.7 Drawing force F = nDpt(TS)( Holding force F = 0.015 Y7{D; (D, + 2.2t +2Ra)* } Symbols: Dp = blank diameter D, = punch diameter original blank thickness, mm TS= Tensile strength, Mpa Y = yield strength of the sheet metal = die corner radius, mm %3D %3D Ra