Some manufacturers face the same problem as the bears in the Goldilocks’ tale.

The maker of a range of corrugated and solid-fiber containers had to pay special attention to the starch it used to make its products - the starch had to be hot, but not too hot. If it exceeded 140°F (60°C), it would start to cook and then gel prematurely. During the manufacturing process, tight temperature control must be maintained in the starch-holding tanks.

With more than 90 years experience, Pittsburgh-based Chromalox solved the customer’s problem by using a heat transfer system that can limit the tank’s temperature to 140°F (60°C).

In addition, the method allows the heat to spread across a large surface area, which minimizes the watt density on the temperature-sensitive starch product. Chromalox provided multiple microTherm systems, specifically the CMX-250-9, 480 V, three-phase 9 kW unit. Chromalox CMX systems typically include the following components:
  • Incoloy-sheathed immersion heater.
  • Cast-iron bronze-filled centrifugal pump rated 30 gal/min at 20 psi TDH with 0.75 hp motor.
  • Open- or closed-loop cooling with a 3.8 ft2 heat exchanger.
  • Contactor-based control panels with overloads, fusing and temperature control.
  • Common options such as SCR power control, digital communications and higher pumping capacity.
Engineers at Chromalox note that heat transfer systems are suited for heating temperature-sensitive products when the process calls for a heat transfer system and heat exchanger. Immersion heaters, which come in direct contact with the product, cannot be used because of higher watt densities and the difficultly of controlling the heating element skin temperature to prevent burning.

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