Bulk Forming Flashcards
Rolling
Plate ( > 6mm) is fed through multiple rollers till desired thickness achieve
Forging
Work piece is put between two dies, compressive method
Extrusion
Work piece is forced through a die
Drawing
Diameter is reduced by pulling, Tension
Open Die
Work is compressed between two dies, material flows in laterally
Impression Die
Die has a cavity Mould, Flash is formed which cools quicker and contrains the material within the die
Flashless forging
Work is completely constrained
Upset forging
Used to create, bolt heads, screw heats etc, when only one parts needs to be forged
Indirection extrusion
The material is forced back up around the punch
Die Angle geometry
Low Angle - Increased Friction, more force needed
High angle - More turbalence in ram force
Die heated to prevent sticking
Defects in extrusion
Centre Burst - Too much tensile stress, internal cracks
Piping - Sink hole develops during direct extrusion T end of billet
Surface Cracking - High extrusion speeds and temperature at surface
Wire drawing
0.03 - 4mm diameter
