Manufacturer Discovers Advantages of Customized Electric System from Watlow

Problemcustom electric system

A manufacturer needed to reheat water and convert it to steam downline in their process. They wanted to eliminate emissions and keep costs down, so they chose an electric kettle reboiler to meet these requirements. For this job a number of ASME specifications would have to be met.


Watlow responded with a circulation heater designed in a conical shape with a tapered end.

The large heater included nozzle connections for inlet and outlet piping, drain and level control. A pressure relief valve and vent connections were also required.

Watlow also met the following requirements:

  • 100 percent radiography on all weld joints
  • Brinnel hardness testing
  • Ultrasonic testing on nozzles
  • Tolerances within 1/16 inch instead of the standard 1/8 inch

Because of the outdoor atmosphere, the control panel was designed with a NEMA 4X enclosure. An air conditioner was necessary to protect the panel components from overheating.

The panel included:

  • Watlow QPAC power control
  • High-limit device
  • Relay logic control scheme, featuring remote alarms and annunciations

The application was successful for the customer due to Watlow's ability to follow the ASME code requirements as well as the customer's lists of requirements. In addition, the customer benefited from the use of an electric, rather than gas, system. The advantages of electricity include better controllability, no emissions and low capital equipment cost.