Producing with a Trumpf Punch Press Mike Miller Emech 210 4-10-02
Specifications of a Trumpf Model TRUMATIC 500 ROTATION Punch Press • 220 kN Punching force (49,500 lb) • Handles up to 8mm thick sheets (5/16 in) • Linear tool magazine that holds 18 tools • 121.5 x 65 in working range • 60 in/sec X-axis travel speed, 40 in/sec Y-axis travel speed • 900 hits per minute high speed punching • Sorted removal of finished parts • Light barrier safety fence Info from www.trumpf.com
How it Works • The hydraulic head rapidly forces the inserted punch through the piece. • The die of just over the size of the punch prevents the metal from moving or bending.
Strength of Materials Reasoning • Applied shear force over area exceeds the materials Ultimate shear strength. • Ex. 1 in. Circular Punch τ = V / A where V = shear force and A = thickness times circumference τ = 49.5 kip / ( 5/16 * 2π(0.5)) in2 τ = 50.4 ksi
Strength of Materials Reasoning • The ultimate shear strength for 2014-T6 Aluminum is 42 ksi while it is only 27 ksi for 6061–T6 Aluminum • The applied shear stress has obviously exceeded the ultimate shear strength, causing the piece to break • Smaller punches apply larger stresses because of the decreased area, this allows for slightly thicker plates to be used if necessary • Punches over 1 in. are angled on the bottom, also reducing the area the force is acting over
Punching Possibilities Factory Example Piece
Punching Possibilities Fancy Range Hoods Refrigerated Truck Parts Various Airplane Parts
For more information: www.trumpf.com