Inherently Temperature-Safe cables are cables that have no significant output at their withstand temperature. More

The maximum temperature a heating cable can be exposed to before it is damaged. Sometimes referred to as maximum exposure temperature or design temperature

The surface of the heating cable must not exceed the maximum temperature of the constructional materials or the Termperature Classification if installed in a hazardous area. This is ensured by limiting the pipe or workpiece temperature to a safe level either by design calculation or by means of temperatue control devises.

Constant Wattage cables do not regulate they have the same output irrespective of pipe or surface temperature

Internal Pipe Tracing

The Problem
Internal heat tracing is used to internally heat pipes where external tracing is impractical. Such situations may include:
buried pipes sections under roads pipes in ducts submerged pipes inaccessible pipework pipes with existing insulation Pipework may typically contain fuel oil, or other fluids
Pipework may typically contain fuel oil, or other fluids.
The Solution

Intertrace		Installation of Intertrace for Mobil, Australia
Heat Trace manufacture and supply a complete system which may comprise: heating circuits, metal sheathed, mineral insulated fabricated stub pipes for exiting heating cables junction boxes for power, series, or star point connections temperature controls; either capillary or solid state control panels thermal insulation (where appropriate)
Design
Heat Trace design the system so that the heating load attains the desired pipe temperature. Loads are calculated to take account of losses from pipes which may be buried in soil/sand etc, surrounded by air, or submerged in water. In the latter case, a closed cell insulation system will almost certainly be required, whilst insulation may also be necessary, or desired, for open pipework. Cables are rated so that they operate at safe temperatures. Sheath materials are selected to be chemically resistant to the fluid in which they are immersed. Cables may be single or multiple runs arranged for single or three phase connections.

Installation

Heat Trace normally install or supervise the installation of the system. This includes drawing of the cables into the pipes, heater cable jointing, anchoring of circuits at pipe exit points and termination via specially fabricated sealed stub pipes into junction boxes. After installation of temperature controls and, where required, control panels/thermal insulation/electrical mains wiring, the circuits are meter tested for continuity and insulation resistance prior to filling the pipework and commissioning. Auxiliary circuits are often installed for emergencies.