Omni Instrumentation & Electrical Services recently completed the installation of process pipe tracing on a new 2.5-inch stainless-steel fat line running from an indoor, 10,000-gallon storage tank to a truck loading platform. The design required that temperatures be maintained at 108°F (42.2°C) over 450 linear feet of pipe. The heat tracing manufacturer’s applications engineer recommended 7.5 watts per linear foot with 2-inch insulation to meet our temperature goals.
Two heat tracing circuits were run, one for 330 ft. of indoor piping and 120 ft. of outdoor piping. An additional 50 ft. of spare heat tracing cable would be required for wrapping several control valves, manual valves, and a large Coriolis flow meter. Each of the circuits would be set to 110°F and regulated with an internal thermostat. Input power of 277 volts was used as the higher voltage allowed us to use existing small breakers.
The client requested that the heat tracing system be incorporated into their process control system, and the design specified a fairly expensive SCR power controller that had a 4 to 6-week order lead time. This was unacceptable due to the urgency of the project. Omni was able to locate alternative, cost-effective, locally-controlled programmable thermostats that sense line temperature and adjust accordingly. The process control system would monitor the controller with a Form-C dry contact alarm. These changes saved several thousand dollars for the client.
Once the process heat tracing had been completed, it was megohmmeter-tested for continuity and electrical insulation integrity, followed by installation of the 2-inch pipe insulation. The new line was commissioned, and temperatures and alarms were carefully verified. Both systems successfully ran fat through the new heat-traced line to a waiting tanker truck. The client was more than satisfied with the new installation and the substantial cost savings achieved by using alternative, readily-available controllers and existing breakers at the facility.
About Omni
Omni Instrumentation & Electrical Services, Inc., located in New Jersey and Maryland, is a premier instrumentation and electrical contractor, providing superior total care solutions since 1986. Services include instrument installation, tubing installation, instrument calibration, control loop testing, startup and commissioning, power and lighting, process control wiring, BMS wiring, telecommunications and data wiring, fire alarm wiring, security wiring, process network wiring, and control panel fabrication. Omni Instrumentation & Electrical Services, Inc., is certified in Foundation Fieldbus, Profibus, DeviceNet and ASI-Bus installation.
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