3 Fundamentals of press design

442 Solid forming (Forging)
85
Ø53
billet weight
1.275kg
80
Ø50
starting workpiece and fiber flow
in a machined part
Fig. 6.2.1 Comparison of the input weight and achievable geometry for machining and
forming processes
– Reduction/elimination of subsequent machining: Subsequent metal removal
processes are frequently only necessary in the case of geometries
which present a particular problem for forming processes, for
example recesses, undercuts or threads. By using cold forging techniques,
substantial savings can be achieved by reducing investment
in machine tools for metal-cutting and in metal-operating staff.
– Minimal process, logistic and transport costs: This benefit is created as a
result of the low cost of automation where transfer systems are used.
– Generally high productivity: Small workpieces produced from wire on
horizontal forging machines can be manufactured at stroking rates of
up to 200/min. For larger parts manufactured by forging from billet in
vertical presses from billet, production speeds of up to 50 parts/min
are possible.
– Facility for integration of several functions/geometries in a single component:Cold
extruded parts often provide an opportunity for “re-engineering”
to create lower-cost designs. The aluminium oil filter housing
illustrated on the left in Fig. 6.2.2,for example, is cold extruded in
a single piece. This allowed the production of three individual components
– flange, drawn cup and connecting piece. Thus, the complex
welding operation required previously (Fig. 6.2.2, right) could be
reduced to a single extrusion operation.
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998
32
Ø45
billet weight
0.398kg
86
Ø52
starting workpiece and fiber flow
in a forged part