3 Fundamentals of press design

Coil lines
Fig. 4.3.1 Coil line for direct feed of stock material into the press
feed/straightening machine draws the stock on an intermittent basis off
this loop, straightens it and feeds it, correctly positioned, into the press.
Whether the conventional coil feed line or the compact design is
used depends on the material to be processed. Coil stock which is thin
or has a sensitive surface can be very successfully processed using conventional
methods. However, in cases where generally thick coil stock
is being fed to the press, and if the material is suitable for interrupted
straightening, the compact design is generally preferred.
When working with progressive dies and compound dies, the feed/
straightening machine can be released briefly during immersion of the
pilot pins for feed correction (cf. Fig. 4.7.25). This applies equally to roll
feed. For roll feed, the release period is around 0.03s and for the
feed/straightening machine around 0.05s.
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998
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