Metal Forming Success Story
Tougher Stamping Dies and Less Rework
Beckett Gas, Inc., of North Ridgeville, OH,
makes gas burner products for water heaters and furnaces.
The in-house production line turns out stampings by the millions—thirty
million parts a year, to be exact. Beckett’s experience shows
that FortiPhy™ coatings by Phygen outperform other coatings,
and measurably increase the toughness of stamping dies.
Beckett Gas stamps millions of these
gas-burner parts, relying more and more on Phygen CrN
tool coatings to maximize hits between sharpenings. Forms
on the inshot burners, 2.5 to 3 in. wide, are critical,
including the plenum area and the form edge, with a tight
0.030-in. radius. |
According to Rick Roth, Beckett's tool and die
foreman, “Our engineering team constantly presents
us with design challenges that have caused us to continue
fine-tuning our stamping operations. Forming aluminized cold-rolled
sheet, much of which is 0.035 in. thick, to standard tolerances
on burr height (10 percent of material thickness), with increasingly
tight form radii (as tight as 0.030-in. radius), has led us
to investigate our choices of tool steels and tool coatings.
Aluminized stock makes for a very abrasive material and can
really tear up a die.”
Beckett understands the benefits of continuous process improvement,
and it monitors results closely. In one particular part, used
to make the inshot burner for the most popular furnace burner,
D2 tool steel produced 60,000 to 80,000 parts before unacceptable
burrs necessitated sharpening the die. A switch to powdered
metal (PM) tool steel doubled tool life.
The next logical step was application of a PVD tool coating.
With the addition of a TiCN multiple-layer coating, the PM
tool life increased by 50 percent, raising output to 200,000
parts between sharpenings. While happy with the increased
production, the downside of the hot-process coating was obvious.
Roth explains, “We'd get form tools back from the coater and
in some cases, form rings would shrink by as much as 0.007-inch
because of the hot coating process. We'd have to send the
tool back and have it fixed, further delaying production.”
Roth contacted Phygen after learning about the lower application
temperature of FortiPhy UltraEndurance™ coatings. “The
Phygen coating goes on at only 950° F,” says Roth, “therefore
it does not cause any distortion to our tools.” In addition
to a reduction in distortion, Roth found FortiPhy coatings
made his tooling even tougher. “The result,” he said, “was
another 25-percent increase in the number of hits between
sharpenings.”
An inshot die reveals an array of
tool coatings, as Beckett looks to eventually coat nearly
all of its form and cutting tools with Phygen FortiPhy
CrN Coatings for metal stamping. |
Not only does the coating maximize
hits between sharpenings, but it goes on colder than other
coating processes, says Beckett’s Roth, avoiding distortion
of components such as the form rings used in water-heater-burner
flame-spreader tools. |
A follow-on test in another difficult stamping operation
confirmed Beckett's earlier findings. The FortiPhy coating
outperformed a hot-applied thermal-diffusion coating on dies
used to stamp tough, abrasive, aluminized sheet steel. In
that test, hot-coated tools made 400,000 hits before the corners
of the tools were destroyed. FortiPhy coating took the same
tools to 600,000 hits, without the risk of dimensional change
and rework that hot coatings can cause.
The key to FortiPhy coating's exceptional toughness, low
coefficient of friction, and corrosion resistance is its uniform,
nanocrystalline structure. Phygen’s patented plasma acceleration
process improves upon traditional PVD methods to produce the
most uniform coating deposition layer possible, with exceptionally
high adhesion. Having solved the uniformity problems inherent
in the PVD processes of the past, Phygen can apply thinner
coatings that outperform thicker, less-uniform coatings. In
addition, Phygen coatings are applied at much lower temperatures.
Low-temperature processing and thinner coatings help keep
critical tool dimensions within tolerance, without the costly
rework of other processes.
Testing at Beckett Gas, Inc. has repeatedly proved that
FortiPhy™ thim film
coatings outperform other coatings, while causing less distortion.
According to Roth, Beckett decided to send additional tooling
to Phygen for coating. Says Roth, “Now that we've converted
one die, we'll continue to send tools there as they need recoating,
about one tool a month, until we convert nearly every coated
tool over.”
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