Tubular Heaters In Small Packaging System Assures Food Freshness


The Watlow salesman had a customer using a cast-in heater from a competitor for his food packaging machines. The inexpensive bimetal thermostat was mounted in the expensive, massive cast-in heater was producing poor heat control.


Within a week, the salesman coordinated an alternative design to decrease costs without sacrificing quality. The alternative involved spot-welding the tubular heater to a flat metal mounting plate with no thermostat (open loop control). Tests revealed wattage requirements of:

  • A 150 watt element in a machine operated in a cold area 50°F (10°C ambient)
  • A 30 watt element in a machine operated in normal areas 70°F (20°C ambient)

The resulting sealing machine can seal small food items (fruits and sandwiches) by pulling down the heated platen over the film covering the products. The value-engineering contributed by the Watlow sales representative took into account cost and simplicity to produce a better product for manufacturer and user.

Value Added:

Watlow's ability to provide timely application support and quick prototype turnaround.