How Quick Die Change is Changing
May 12, 2014Comments
Now more hands-free, controlled, mainstream
Quick die change (QDC), introduced decades ago, has become a staple of lean manufacturing in most stamping shops. Elimination of much of the lengthy press setup times and press downtime attributed to die change in the past advances just-in-time manufacturing. Still, many stampers are in the process of converting some operations to QDC, improving their methods of doing so, or speeding the process even more.
QDC equipment itself—mechanical, magnetic, hydromechanical, hydraulic, spring, electromechanical, swing, sliding, swing sink, wedge, and traveling die clamps; ball, roller, hydraulic, and spring die lifters, bolster extensions, rails, controllers and aligners; carts, T-tables and power pallets; and controls—is being upgraded and their lines expanded to meet evolving requirements for speed and safety (see Fig. 1).
Several die change equipment manufacturers told Stamping Journal what their customers tell them about their challenges with die handling and changeover.
Atlas Technologies Inc. Director of Sales and Applications Bill Rogner said, “We find that stampers are faced with adding jobs to their press cells. These additional jobs require that their press cells must run faster or have more uptime.”
In addition to the increased production stress, manufacturers are faced with die storage and handling problems, Rogner added. “Often dies may be stored outdoors or stacked inside at multiple tiers. These storage methods are not ideal for efficiency, safety, or part quality.”
David L. Fischer, Hilma engineering manager, Carr Lane Roemheld Mfg. Co., pointed to production volume variation as a push for even faster die changeovers and economical die clamp and handling systems. “Shorter runs and more frequent die changes mean more press downtime. So die changes must be quicker.” He added this caveat: “But safety cannot be sacrificed for speed; they need safe clamping systems and ergonomic die exchanges.” (See Fig. 2.)
Chris Keahn is North American sales manager at Tecnomagnete, which makes quick-change magnetic clamping only. He concurred that accelerating die changeover time is still a challenge. “Speeding up quick die changeover time is the main reason people come to us.”
Automated storage and retrieval systems help stamping companies manage die storage and handling issues too (see Fig
Keahn, Tecnomagnete: We have reduced the thickness of our magnetic plates. When retrofitting a press with magnetic clamping, we can now minimize the amount of daylight the plates displace.
Regarding die transporting, we see a significant increase in interest in trackless die transporters. Die lifters are available in spring, pneumatic, and hydraulic models (see Fig
SJ: How has QDC evolved since it first was introduced? Without divulging trade secrets, in a general way, what innovations can stampers expect to see next year? In the future?
Fischer, Hilma: Some customers require hands-free clamping in die change systems, which means auto- positioning and automatic clamp equipment with multiple proximity switches, to integrate the clamp position and status to the press controls. Electromechanical clamps for hydraulic-free applications are another. Magnetic clamp systems with force evaluation systems analyze the clamp conditions and provide the operator with the resultant magnetic clamp force on the die set. 
