Page 81 - MetalForming October 2011

The Science of Forming
Tool Number Two
The second tool readily available for troubleshooting prob- lems with dimensional variation is the laser thermometer gun. These noncontact devices can rapidly obtain pinpoint temperature measurements at different locations on the die or stamping. Stampers can use this data to uncover temperature variations that can cause changes in lubricant viscosity and coefficients of friction, as well as changes in die dimensions. All of these parameters affect material flow and can cause deformation patterns to change throughout the stamping.
Even small temperature changes can be disastrous. For example, consider a die producing acceptable stampings whenstartingproductionat70F,butwhichcaused100-per- cent breakage 15 min. later when the critical areas of the die reached 84 F. This case study can be found in the April 2004 issue of MetalForming, in the Science of Forming column called, “The Die Has a Fever?” The article discusses the simultaneous use of a UTG and a laser thermometer gun to illustrate how temperature and forming severity climbed in sync as production time increased, until the stamping final- ly tore.
The two handheld tools described here will help met- alformers solve various press-shop problems, by obtaining meaningful data for problem tracking and solution evaluation. MF
OMITTHE DRAW BEADS
Save money with smaller blank size, even on high strength steel!
Since 1998, Red Stag has engineered a cushion which has the force and controls for all the flexibility you need for any high strength steel tooling.
Solve motion control problems with multiple-choice answers.
The graphs show actual force/dis- tance performance of the last run. To the right are curves for each of the 12 cylinders.
Tonnage and distance are entered on the tonnage screen. The 12 bars on the right represent the 12 individual cylinders used in the cushion.
A hydraulic cushion with total close loop control and programming with full control on each cylinder with the speed to change tonnage pressure and stroke eight (8) times from 3 o’clock to 6 o’clock. You now have control 360o from maximum blank holding pressure to start the draw-to-metal movement throughout the draw with a dwell on the bot- tom with higher pressure again. You can even remove all draw beads, make your blank smaller saving both steel and money.
Red Stag manufactures the Hydo-Craft hydraulic press
RED STAG ENGINEERING
& AUTOMATION INC.
N2548 Meadow View Court,
Waupaca, WI 54981 U.S.A.
Phone: (715) 258-5074 Fax: (715) 258-5242 Email: redstag@waupacaonline.net Website: http://www.redstag.com
www.metalformingmagazine.com
MetalForming/October 2011 79
1-2Axis
Multi-axis
RMC75 and RMC150 Motion Controllers
• 1, 2, or up to 8 axes
• Synchronized control of position and pressure/ force
• New wizards for quick, easy setup and tuning
• EtherNet/IP and PROFIBUS connectivity
Maximum yield. Lower lifecycle cost. Ease of use. Pick three. Whether you’re retrofitting an old machine or building a new one, Delta motion controllers give you precise closed-loop control for critical industrial applications, where precision maximizes product value. Our field-proven RMCTools software makes it easy to optimize hydraulic and electric servo operations for longer machine life, and interfacing to PCs and PLCs is a snap.
So you see, it’s easy to choose the right box every time.
Just call 1-360-254-8688 or choose your controller at deltamotion.com
See us at Fabtech 2011, Booth 3341