Page 16 - MetalForming August 2010

Stamper
more efficiently meet those larger orders on time.”
Carefully Calculated Purchases
The three fully equipped press lines joined the 32,000-sq.-ft. pressroom in January 2009—overall, the plant offers 180,000 sq. ft. of floor space, including a 20,000-sq.ft. fabrication shop. The 600-ton model, a straightside press, was carefully specified by Wells after evalu- ating the larger dies—weighing as much as 26,000 lb.—used to stamp automo- tive parts.
“I evaluated the point in the stroke where the parts would start to draw,” Wells says, and calculated the energy required, comparing the calculations to the press-energy curves from Aida.
“We needed a more engineered approach to setting up all of the lines,” continues Wells, again thinking back to how the rest of the shop’s equip- ment had been acquired. “We had some undersized equipment, including some cradle straighteners that performed fine
for heavy-gauge work such as stamping 7- to 14-gauge steel brackets, but would show some deficiencies on lighter gauge material such as automotive parts of 0.030-in. stock. So we specified the 600- ton press line specifically for that thin- ner-gauge work, while wanting to run at a 36-in. progression at 25 strokes/min.”
Stamping automotive parts, the 600- ton press processes five different dies on a regular basis, with typical part quan- tities of 10,000; it takes two weeks to complete the cycle. Smaller parts run on the new 200-ton press, a gap-frame model, at about 50 strokes/min.
Focus on Quick Change a Must for Contract Stampers
One of the critical success factors to operating high-volume high-speed press lines for contract stampers is quick changeover, and Wells and his team promptly attacked that operational area.
“For example, the biggest challenge we have on the 110-ton press line,” Wells notes, “which runs as quickly as
100 strokes/min., is that we can run through a 6000-lb., 72-in. coil in less than an hour. We’re changing coils as many as 10 times/shift. All of the stan- dard features on the Coe servo-feed lines, as well as the new alligator-style peeler, have helped us fine-tune the coil-change procedure to just 8 to 9 min.”
One of the most common jobs run- ning on the 110-ton press is stamping small plates for retail-store customers, from 1⁄4-in.-thick stock 2 in. wide. “We stretched the line out as much as we could,” says Wells, describing efforts to dekink the material, “but we still fought coil set and struggled to get the materi- al into the debend station. Here’s where the alligator-style peeler saved us—it captures the coil and forces it straight into the straightener without having to worry about coil set.”
The two-axis peeler table has a tele- scoping peeler blade to reach the lead- ing edge of the coil; tapered ends facil- itate threading of wide as well as narrow coils. Meanwhile, the upper dekinker table includes a motorized threading roll—during threading, the leading coil edge is pinched between this roll and the peeler table, and then the peeler table lowers to dekink the material.
“We like the unit so much that we expect to purchase one for the new 200- ton line as well,” says Wells.
More Quick-Changeover Development to Come
With coil changes down to less than 10 min., Wells and his team aren’t done fine tuning the process to yield addi- tional press run time. He expects to be able to cut coil-change time in half, by enhancing some of the pressroom’s practices and procedures.
“For example,” Wells adds, “we stage a lot of coils lying on their sides on pallets; we’ll look to stage them upright in racks so they’re ready for loading as soon as possible. And, we’ve begun to use end-of-stock sensors so that opera- tors can—with confidence—begin his coil-change process as soon as the end of the coil departs the mandrel, rather than wait for that last 20 ft. of material to run through the press.” MF
www.metalformingmagazine.com
“We Love FortiPhy’s Performance for Heavy Gauge Deep Drawing Challenges and Forming
441 Stainless Steel.”
Michael Stull, Tooling Manager Pentaflex, Inc., Springfield, Ohio
The Tooling Challenge
Draw heavy truck brake drums from 5/16” thick high strength, low alloy steel — 12” diameter by 5.5” deep draw and 􏰀.005” ID tolerance. Solve quality and galling issues with prior coatings (TD, TiN and others) that had a major impact on downtime, production rates and tooling costs.
The Phygen Solution
FortiPhyTM UltraEndurance Coating has given Pentaflex:
• More than 4000% uptime improvement from 900 to nearly 40,000 parts between polishings.
• Repeatable 1.67 Cpk, with no wall diameter structural or thickness changes.
• Minimum $65,000 yearly savings – less overtime, press down time & tooling replacement costs caused by excessive galling & premature tool wear.
• Improved quality in large transfer die stampings (example in left photo)...galling downtime & required polishing in tough form areas reduced by 80%.
• A cold coating process that doesn’t generate material distortion or dimensional change like a hot coating. FortiPhy’s application temperature eliminates the guess work/problems and also allows multiple recoating of the same tool eliminating the need to scrap tools after a single production run.
• Visit www.phygen.com/Success_Pentaflex.htm for the full story
14
Phygen Coatings, Inc. / Toll Free 888.749.4361 / phygen.com / email: tech@phygen.com METALFORMING / AUGUST 2010
New Enhanced Size Capabilities