Heat Tracing 101: Protecting Pipework From Freezing and Heat Loss
Self-regulating vs constant-watt heating tape and where each is used.
Heat tracing replaces the heat that pipework loses to its surroundings. Used with insulation, it keeps pipes from freezing and holds process fluids at a set temperature.
What heat tracing does
An electric heat-tracing cable or tape runs along the pipe, under the insulation, and gives out heat. If its output at least equals the heat lost to the cold air, the pipe stays above the target temperature. It works with insulation, not instead of it.
Two main uses
- Freeze protection: keeping a pipe above freezing (or above the pour point of the fluid) in cold weather.
- Temperature maintenance: holding a fluid, such as viscous oil, at a higher temperature so it keeps flowing.
Working out the need
The heat required depends on pipe size, insulation type and thickness, the lowest ambient temperature and the temperature to be maintained. Heat-tracing makers publish tables and software to calculate watts per metre. Longer insulation thickness reduces the load.
Installing it properly
Fix the tracing along the pipe with tape, add extra at valves, flanges and supports, which lose more heat, and cover it all with weatherproof insulation. Use the right end seals and connection kits and never overlap or cross self-limiting cables unless the maker allows it.
Control and safety
Use a thermostat or controller to switch the heat according to pipe or ambient temperature. Add earth-leakage protection as the regulations require, and mark the pipe so that people know it is traced. Hazardous areas need approved equipment.
Key Takeaways
- Heat tracing works together with good insulation.
- Size the heat output from pipe size, insulation, ambient and target temperature.
- Add control and earth-leakage protection.
This article is general guidance. For a recommendation for your own application, contact our engineering team. Heating tape and heat tracing →