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PLATING AND ANODIZING: HEATING AND CHILLING

THERMAL CONTROL

IN METALS FINISHING

emperature regulation is a field that is constantly develop-
ing, as ever-more precise systems with new and more
Tadvanced algorithms enter the market. It reached a certain
plateau with the standardization of microprocessor-based units,
but there is still room for improvement.
There are also the issues of cost and durability to watch for, even
when the technology itself has proven it is viable. Measuring
temperature extremes exposes instruments to harsh conditions,
so they have to be designed and assembled in a way that will not
fail after a short period of use.
Much of the thermal control equipment on the market is cus-
tom-made, rather than off-the-shelf. Plants in this field often tend
to be designed ad hoc by their owners, starting very small and grad-
ually adding components from various sources as the business
builds. Titan Industrial Heating, which specializes in the area, and
particularly in autocatalytic nickel plating (often called electroless
nickel plating), stresses that it has no standard stock products that
serve this industrial category. However, it can custom manufacture
to users’ exact requirements, and has extensive experience in
nickel plating, which is performed in a heated tank.
“Correct process temperature and safety concerns in chemical
plating tanks require constant temperature monitoring,” Titan
says. “This is often done with thermocouples of different dissimilar
metals connected to a digital temperature controller. Maintaining
correct temperature in metal finishing tank and limiting outside
parameters like evaporation of solutions can be easily controlled by
installing the thermocouple at correct location.”
For example, if the tip of the sensor in a chemical process tank is
located at the bottom of the tank, the control can not sense the
“raising heat” and will consequently stay on to meet the demand of
the control. It is therefore essential to be sure the sensor is located
in the top 30 percent of the process solution.
“Thermocouples are cost effective and easy to exchange,” the
company points out. “In case of a thermocouple failure, the digital
temperature controller will alarm.”
Besides constant control of the temperature, Titan also recom-
mends installing a liquid level safety control. This is a vital safety
device in plastic tanks (those made of polypropylene, or PTFE
coated) and also described as a good investment in metal tank
because solutions evaporate, tanks fracture, erode, corrode or
disintegrate due to electrolysis.
Titan’s capabilities extend from small controls to heat a simple
tank, up to those needed for a new shop with RS-485 integration
with data collection. Such a system has the ability to notify the user
by phone of the status of the system.
Today’s higher demands on accurate process temperature con-
trols in plating tanks, documentation and safety concerns, require
the use of digital temperature controls, the company stresses.
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