Wax Maintained at Steady Laminating Temperature in Converted Press Tank

over-the-side immersion heater

The Challenge

In this lamination process, up to four sheets of paper are laminated at one time by a press, from either 19'/1," or 241/x" rolls, depending upon which width is being made. The adhesive agent is 1290Y Wax. The consumption of wax when running at full speed is 100 lb. in 15 minutes. Two wax tanks are used: One on the press containing 225 gallons and a 75 gallon supply tank. Wax is held at melting temperature in supply tank, and poured into the machine tank as needed. The tanks had been heated by gas which was unable to maintain wax temperature, particularly when press was operating at full speed - 525 rpm. Also, the non-uniform heating caused the viscosity of the wax to vary, resulting in fluctuating thickness of coating on the paper.

The Solution

Chromalox electric Immersion Heaters, Type TL023OXX, 230/240 volts, 3 KW each, were placed in the tanks with low installation expense. They were simply "dropped" into the tank with the terminal housing resting over the side.  Two heaters are used in the press tank, one in the supply tank. One Chromalox Type AR-2529 thermostat in each tank automatically controls each heater to maintain wax temperature.

Benefits

  • It provides rapid heat-up and maintains wax temperature regardless of rate of consumption.
  • It is safe - eliminates the danger of open flame.
  • No more heat is used than is absolutely necessary with direct immersion heating.
  • Elimination of the open gas flame keeps press room discomfort at a minimum; no humidity is introduced by electric heat.
  • Wax viscosity is constant, assuring uniform thickness of the laminated paper.