Using ROEMHELD North America’s Hydro-mechanical Clamping Nuts for die changes, Whirlpool achieved annual savings of 6,600 hours. And this impressive efficiency boost is realized in just one of their factories!

Effective die-change practices begin with meticulously organized workstations. Whirlpool has taken steps to enhance this process by tailoring Creform material-handling carts to streamline the organization of the new Hilma hydromechanical clamping nuts and accompanying bolts. These customized carts serve to provide clear visual cues for die setters and press operators.

During the years 2013 to 2014, Whirlpool's premium cooking operations plant in Cleveland, TN experienced significant growth in home-appliance sales. The surge in demand posed challenges for the plant as it strove to keep pace with production requirements. While the increased workload was welcomed, it also created a demanding environment that required managers to remain vigilant in order to effectively manage the escalating activity levels.

Overcoming Challenges and Pursuing Continuous Improvement

The Whirlpool plant was relatively new, having been inaugurated in 2012, and was encountering typical growing pains. As a showcase facility, it attracted hundreds of new employees, presenting a significant training challenge. Additionally, the plant received thousands of stamping dies and dozens of presses with varying tonnage capacities.

The relocation of several production lines across town and the integration of new processes into the facility while meeting consumer demand for premium cooking products posed a substantial challenge. However, through diligent effort and hard work, the plant successfully accomplished this task and was rewarded with steadily improving productivity measures.

Fabrication manager, Jim Stewart says, “While a lot of our measures have improved significantly this year, we recognized several opportunities for even further improvements in a number of areas.”

The Press Shop Project

In January 2015, Stewart and value-stream director, Gene Sparks, sponsored the plant’s Press Shop project.

The team aimed to bring continuous improvement in areas including:

• Error-proofing all die changes
• Ensuring safety checklists are used for al startups, changeovers, and shutdowns
• Building a robust safety-training program for new and temporary employees
• Properly maintaining equipment and keeping work areas clean
• Ensuring proper ergonomics for workers with varying physical abilities

“We developed 29 different initiatives to improve those six target areas,” explains process engineer Ted Webb, Press Shop capability coach and a member of the primary project team. “Among them were several action items targeting die changes, including creating a die-setter job description.”

A primary focus of the die change-related initiatives was the enhancement of the process for clamping and unclamping dies. Key challenges included ensuring consistent torque during bolt tightening and developing a method for tightening and loosening that was not reliant on operator size or strength.

“Sinec we’re averaging more than 100,000 changeovers per year,” says Stewart. “On our six-press stainless line, for example, we might change each press 50 times per week—offering a huge opportunity for increasing efficiency.”

Die Clamping Solution at FABTECH

During FABTECH 2014 in Atlanta, the press-shop team from the plant embarked on a mission to enhance die-change efficiency. At the ROEMHELD North America booth, they stumbled upon a game-changing discovery: the Hilma hydromechanical clamping nuts. These nuts, in contrast to traditional T-bolts, demanded only a fraction of the torque to secure a die. Promptly upon their return from the exhibition, Stewart and his team wasted no time in submitting a purchase order for dozens of these innovative nuts.

The implementation of the new clamping nuts, which seamlessly fit into 90 percent of the facility's dies without necessitating modification, proved to be remarkably straightforward. The setter simply inserts the T-bolts and clamping nuts into the slots on the press bed and hand-tightens the nuts to secure them against the die. Subsequently, with just one or two turns using a 6-inch ratchet, the required torque is effortlessly achieved.

“In all, we’ll invest several thousands of dollars per press to employ the hydromechanical nuts,” he shares. “And we plan to put them on every press. That’s a big investment (360 clamp nuts, rated to 22,400 lb. of clamping force, along with 360 1- by 6-in. bolts), but we expect immediate payback in terms of time savings and ergonomic advantages. The new clamping nuts have decreased our die-change times by at least 4 minutes per change.”

To ensure seamless organization and accessibility of the nuts, the project team devised Creform kitting carts at each press, stationed conveniently within the facility in Greer, SC. These carts served as dedicated storage units for the nuts, allowing die setters to easily locate and utilize them during the die-changing process. This systematic approach provided die setters with clear visual cues, significantly reducing the risk of missing or leaving behind nuts during both die setting and removal operations.

“Half of our dies were not designed in-house; they came from other facilities,” adds Webb, “which created a challenge when we looked at standardizing on quick-change equipment. For example, we couldn’t find another mechanical solution or a magnetic system, that would work with such a high percentage of our dies when taking into consideration the frequency at which we change dies and our vast range of die sizes (as large as 9 ft. long and 4 ft. wide).”

Streamlining Operations: No Chance for Error

The plant began its mission to integrate hydromechanical nuts into its presses in May 2015, with an initial addition of 72 nuts to the stainless line. Following this successful implementation, another 72 sets were integrated into a wrapper line by the end of June. Stewart wasted no time and promptly filed another purchase order to equip additional presses by the end of September.

“The die setters love the new clamping nuts,” Stewart says, “and I can’t wait to get them on all of the presses. We’re eliminating opportunities for die damage, and we’re reducing our changeover times.

Stewart continues, “The setter slides the T-bolts and clamping nuts into the slots on the press bed, then hand-tightens the nuts to secure them against the die. He then makes one or two turns with a 6-in. ratchet to reach the required torque. A button pops on the nut at that point—no chance for error.”