A Clean Way to Plate

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I.
This cabinet is used lor neutral salt spray testing at
Tan"?. Emphasis ispiacedoo developing finishes
that are attractive and long-lasting.
A Clean Way to Plate
Precious Metals Plater Finds Practical Solutions for Pollution Control
Plating companies are finding it
necessary to make major changes
i n their processes so they can
eliminate the use of chemical
solvents and freon in cleaning
technology and continue to
manufacture without risking
damage to the environment.
Family-owned Tanury Industries,
Lincoln, RI, began making changes
in plating processes years before
the changes were required. The
company i s now solvent-free with
its plating processes.
Here i s how Tanury found
practical solutions to environmental problems while continuing to
grow and diversify in the plating
business.
anury Industries is one of New
England's largest independent
gold electroplaters. Founded in
1948 as Tanury Brothers, the
company is now in its second generation
of family leadership.
Starting out in a 3,000-sq-ft facility in
Providence, the company now operates
from a 25,000-sq-ftfacility in Lincolnwith
annual sales of $10 million.
lnordertosefvean increasing need for
all types of plating, the company has
installednewtechnologyandequipment,
suchasgoldunitsformicrongold plating,
new processes for palladium, light and
darkruthenium, platinum, nickel-free,and
electrophoretic(E-coat)plating.Thecompany has also invested heavily in research and development of new technologies to keep itsprocessespollution
free and in compliance with EPA requirements.
T
Eliminating Solvents
Jim DiNunzio.vice presidentof salesand
marketing, saysTanury'sdecisionto eliminate solvents was difficult because solvent cleaners are proven to be effective
in the electroplatingprocess. The use of
chlorinated solvents (such as trichlorethylene) are among the most efficient
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methodsof cleaning and degreasingpa&
before plating. Freon is also an effective
drying agent in the process.
DiNunzio says the greatest challenge
was evaluating the large number of systems on the market and finding the right
process for Tanury. "We found that a lot
of companies offered products in this
market, but some just wouldn't work for
us,"hesaid. Forexample,oneair-sprayer
device that the company tested would
actually blowsmall parts, such as jewelry
pieces, off the plating rack.
Tanury's method of eliminating solvents was a combination of traditional
and new technology. In place of chlorinated cleaning solvents, the company
has gone to an aqueous-basedsolution.
The solution is incorporated into the existing solvent tanks. A few minor equipment changes (including the removal of
some filters) made the process possible
at a cost of about $2,000.
The new process accomplishes the
desired cleaning effect through a series
of aqueous soaks and ultrasonics. The
process has more steps than the chlorinated solvent process and the action of
the aqueous-based solution is slower,
requiring a longerprocessingtime. In the
end, however, it is just as effective.
Plating and Surface Finishing
L
~
~
,
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and marketing.
The change-over from solvents to the
new process took more than a year becausethecompany tookthe time toevaluate a large number systems before making the change.
::iiminating Freon
Tanury installed a hot-air oven to replace
its freon dryer. The oven Tanury selected
is acustomizedcombination blow-offwith
dryer. There are two steps in the drying
process. A conveyor carries the racked
parts past a chamber where fluid is literallyblownfromthepart.Allresidualmoisture is removed by convection dryer.
Tanury builta5,OOO-sq-ftadditionto its
facilitytoaccommodatethe conveyorized
unit. Because much of the conveyor is
ceiling-hung, extra storage space was
created in the addition.
Thedryerwaspurchasedfor$lOO,OOO.
With the cost of freon approaching
$200,00O/year, however, the company
Taysthedryerpaidforitself in six months.
Other Changes Coming
Tanury is turning its attention to other
safety and environmentalconcernsthese
days, It plans to eliminate the use of
cyanide within the next two to three
years. One source of cyanide is in copper plating chemistry used for adhesion. The process is easy to plate and
easy to plate on.
Tanury officials say the greatest challenge in eliminating the use of cyanide
will probably not involve much money,
but will involve time. Alkaline-copper solutions are now available and Tanury is
already installingits first alkaline-copper
bath. The companysays evaluatingproduct performance with this technology is
expected to take several months.
Diverse Products
Tanury's growth can be attributed in Part
to its diversification beyond the tradiIionaljewelry market, says DiNunzio. The
company has expanded into writing instruments, giftware, eyewear. and automotive ornaments.
October 1993
Writing Instruments
When A.T. Cross launched its Signature
Series, the company had an unusual
plating requirement. They wanted more
than 5 microns of gold on their writing
Instruments.
Most decorative plating is 1 micron of
gold or less because as the thickness of
the precious metal increases so do the
problems associated with the process.
Automotive Trim
When the automotive industry became For example, in order for a company to
interested in offering an exterior gold plate 5 microns (200 mil) of gold, the
trim package, Tanury developed an in- product must stay in a regular plating
terest in plating for the automotive in- bath for about two hours. The longer the
dustry. The problem was that most plat- product stays in the gold bath, the higher
ing companies were not able to pro- becomes the potential for stress fracduce a product that could meet the tures, discoloration and hazing.
Working closely with A.T. Cross engirequirements for holding up in the constant exposure of extreme weather and neers, Tanury developed a specialized
plating process that plates the product
adverse road conditions.
200 microinches of gold without
with
According to DiNunzio,Tanuryworked
with GM senior product engineers to de- stress while achieving a desired uniform
velop GM Specification 6270M, "which color on the entire gold deposit. The
dictated environmentaltesting specifica- Signature series was successfully
tions for exterior gold ornamentation to launched by A.T. Cross in early 1991.
meet or exceed five-year durability requirements." The company invested in Anticipating Needs
an environmental testing laboratory that A spin-off of Tanury's successful diversiwas subsequently GM approved.Tanury fication is its reputation among customalso co-developed a proprietary protec- ers for being more than just an elective coating'capable of withstanding ex- troplater, says DiNunzio. "The combined
knowledgeandexperienceineach areatreme weather conditions. It worked.
In 1988. GM approved Tanury as an jewelry, writing instrument, eyewear and
OEM supplier. Cadillac, a product of GM, automotive-helps the company to recbegan offering the OEM gold ornamen- ognize and anticipate the needs of inditation option that same year. These vidual customers," he said.
Techniques developed for one market
developments have enabled Tanury to
are
found useful in other markets. For
move forward with the gold ornamentaexample,
environmental laboratory testtion program.
ing developed for the automotive market
is now used by most of Tanury'scustomers.
Eyeware
Another example is the concern of the
Randolph Engineering, a manufacturer
jewelry
industry with export issues over
of eyeware, is known for diligently monitoring the field performance of the eye- nickel content. Many users of jewelry
glass frames produced by the firm. The have developed an allergy to jewelry
company also evaluates every product products that contain nickel. DiNunzio
says Tanury anticipates that the issue
that is returned by customers.
Randolph began working with Tanury could affect other industries, or could
in 1989 in an effort to improve the corro- even become a domestic issue in the
sion resistanceand wearabilityoftheeye jewelry industry. The company now Offrames the company manufactures. To fers nickel-free processes and has even
accomplish this, Tanury started a testing launched an educational campaign to
and evaluation program in its in-house inform its customers about the issue.
DiNunzio says there is no doubt that
laboratories. The program lasted for
Tanury
will continue the same way in the
three months. Microscopic testing of
future.
Eliminating
pollution and toxics,
Randolph's base metals indicated that
certain prefinishingoperationscouldmini- and supplying customers with a safe,
mize corrosive attack on the base-metal. dependable product, will continue to be
Neutral salt spray (100-500 hours) and prioritiesfor the company. 0
oermiration
(48-96 hours) test results
,
.
helped TanuG to "fine tune Randolph's
plating specification and to produce a
product with improved wearability and 'DuraClear' was ca-developed by Tanury lndus
performance.
mes and Quality Spraying and Stencilling Co
Whendiversifying,thecompanylooked
formarketsthatneededspecification plating. Markets that were targeted included
the writing instrument, eyewear and automotive industries because those markets were moving into an era of highquality, decorativefinishessuch asthose
found on high-quality jewelry.
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