Heat Tracing for LNG Terminals
LNG terminals combine cryogenic temperatures, flammable gas and strict safety requirements. Heat tracing there is not about keeping LNG warm — it is about protecting the water, sample, instrument and utility lines around the cryogenic equipment, and about doing it with certified kit.
Where tracing is applied at an LNG terminal
- Water, fire water and utility lines exposed to freezing
- Instrument air, nitrogen purge and sample lines
- Analyzer sample conditioning systems
- Drain and vent lines that can hold moisture
- BOG (boil-off gas) heater and compressor auxiliary lines
- Loading arms and marine loading area utility lines
Design points
1. Cryogenic equipment is insulated, not traced
LNG lines and cold boxes rely on insulation and vacuum; tracing them would be pointless and dangerous. Focus tracing on the ambient-temperature lines that serve them.
2. Freeze protection for water and utilities
The same freeze risks as any plant apply — and at an LNG terminal, a frozen fire water line is a safety issue, not a convenience issue. Trace with alarms to the control room.
3. Hazardous area certification
LNG vapour zones are classified. Cables, terminations and enclosures must be certified for the zone and gas group, and the temperature class must be verified for methane.
4. Cold spill and low-temperature exposure
Equipment near potential LNG spill areas must tolerate low temperatures; check jacket and enclosure material ratings, not just certification.
5. Instrumentation and analyzers
Sample lines need the analyzer's temperature window, often narrow; use precise control and verify sensor placement.
6. Maintenance access
Terminal equipment is congested and access is controlled; design junction boxes and tracing so maintenance can be done in a shift, with documentation that matches reality.
Scope checklist
| Item | Confirm |
|---|---|
| Lines | Water, fire water, IA/N2, samples, drains |
| Classification | Zone, gas group, temperature class |
| Ambient | Minimum temperature, wind, marine exposure |
| Analyzers | Temperature window, sample conditioning |
| Power | Panel location, backup, alarms to DCS |
| Access | Maintenance windows and permits |
Common mistakes
- Trying to trace cryogenic lines instead of insulating them.
- Certified cable with uncertified junction boxes in a hazardous area.
- No freeze protection or alarms on fire water lines.
- Ignoring low-temperature rating of jackets near spill areas.
- Designing for construction access, not maintenance access.
LNG terminal project?
Send the line list and area classification. We design certified tracing for the ambient-temperature systems around the cryogenic equipment.
Request a Quote