Page 32 - MetalForming January 2011

Ask the Expert
Tooling Update
Die-Change Rail Car, Multi-Cell Storage Rack
Green Valley Manufacturing, Inc., Mt. Zion, IL, has developed a manual die-change rail car and multi-cell storage rack as an economical
solution for supporting a cellu-
lar manufacturing process. This system stores all of the dies
right at the press. The existing die
is extracted from the press onto
the single-station rail-mounted
die car, which delivers the die to
its storage location. The new die then is loaded on the rail car
and inserted into the press—all by a single operator.
Green Valley Mfg., Inc.: 217/864-4125; www.greenvalleyinc.com
Precision Punch and Die Grinding
Mate Precision Tooling, Anoka, MN, has introduced the ValuGrind precision grinder that lets fabricators precisely regrind punches and dies to maintain optimum condition.
Available for Thick Turret or Trumpf-style tooling, ValuGrind comes completely fix-
Tool Steels
Patricia Miller, senior technical manager, Bohler-Uddeholm Corporation
Q:When blanking and forming advanced high-strength steels
(AHSS), at what point (790 or 980 MPa tensile strength) should a stamper con- sider using a die material other than D2 for draws or S7 for trims?
A:With the move to AHSS, the process window narrows. D2, S7 and A2 tool steels have nonuniform mechanical proper-
ties, are unstable under high-pressure con- ditions and do not permit the use of coat- ings. A form tool for steel over 800 MPa requires remelted or powder metallurgically produced tool steels, coatings or the new nitrogenated PM steels. For blanking tools, this demand can be required as low as 500 MPa with thickness of work material over 1.5 mm.
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30 MetalForming/January 2011
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