Description
Electrically Heated Tubing Bundle with Power-Limiting HPT Heat Tracing
Thermon TubeTrace® with HPT™ is an electrically heated tubing-bundle solution designed for freeze protection and temperature maintenance of process and instrument tubing in applications where high-temperature exposure is possible.
The system combines process tubing, HPT™ power-limiting heat tracing, heat-reflective tape, non-hygroscopic glass-fiber insulation and a protective polymer outer jacket into an integrated tubing bundle. Thermon specifically identifies TubeTrace with HPT as an industry-standard solution for high-temperature emissions and process analyzer applications.
Key Features
- HPT™ power-limiting heat tracing
- Cut-to-length heating cable
- Designed for freeze protection and temperature maintenance
- Maintenance temperature from approximately 5°C to 177°C
- HPT heater exposure capability up to 260°C (500°F)
- Low start-up current
- Reduced risk of overheating compared with constant-watt designs
- Suitable for ordinary and hazardous areas
- Glass-fiber insulation
- Heat-reflective tape
- ATP or TPU polymer outer jacket options
- Suitable for high-temperature emissions and process analyzer applications.
What Is TubeTrace with HPT?
TubeTrace with HPT is a factory-assembled electrically heated tubing bundle.
Instead of installing the process tube, heat tracing, insulation and protective jacket separately, these components are integrated into one assembly.
The basic construction consists of:
Process Tube → HPT Heat Tracing → Heat-Reflective Tape → Glass-Fiber Insulation → Outer Jacket
This integrated construction provides a controlled thermal environment around the process tube while also protecting the tubing from the surrounding environment.
HPT™ Power-Limiting Heat Tracing
The most important feature of this product is HPT™ power-limiting heat tracing.
Unlike a conventional constant-watt heating cable, HPT changes its heat output in response to the surrounding temperature conditions along the circuit.
Thermon identifies several benefits:
- Heat output varies according to surrounding conditions.
- Lower risk of overheating the tube or process product.
- Low start-up current.
- Cut-to-length capability.
- Suitable for ordinary and hazardous areas.
This makes HPT particularly useful for tubing bundles where temperature conditions can vary along the length of the installation.
Temperature Maintenance
TubeTrace with HPT is designed to provide freeze protection or temperature maintenance from 5°C to 177°C for the tubing.
The HPT heating cable itself can withstand continuous temperature exposure up to approximately 260°C (500°F).
This distinction is important:
Maximum heater exposure temperature ≠ normal maintained tube temperature.
For the standard HPT TubeTrace configuration, Thermon specifies a maintenance range up to approximately 177°C, while the heating cable’s maximum exposure capability is higher.
High-Temperature Applications
TubeTrace with HPT is particularly suitable for applications where the tubing may experience elevated temperatures.
Thermon specifically describes the product as an industry-standard solution for:
- High-temperature emissions applications
- Process analyzer applications
- Instrument tubing
- Process sampling
- Industrial analyzer systems.
This makes it particularly relevant to industries such as:
- Power generation
- Petrochemical
- Oil & gas
- Chemical processing
- Refineries
- Industrial manufacturing.
CEMS and Process Analyzer Applications
One of the major applications for TubeTrace with HPT is the transportation of samples to process analyzers.
In analytical systems, the sample may need to remain above a specified temperature to prevent condensation or changes in sample composition.
A heated tubing bundle provides a controlled thermal environment around the sample tube.
Typical applications include:
CEMS
Continuous Emissions Monitoring Systems can use heated sample lines to transport emissions samples between the sampling point and analyzer.
Process Analyzers
TubeTrace with HPT can be used to maintain the temperature of analyzer sample lines where temperature control is important.
Industrial Instrumentation
The bundle can also protect instrument tubing from freezing and maintain the required process temperature.
TubeTrace Construction
Thermon’s specification identifies five primary components in the TubeTrace with HPT construction:
| Component | Function |
|---|---|
| Process Tube | Transports process fluid or sample |
| HPT Heat Tracing | Provides electrical heating |
| Heat-Reflective Tape | Helps distribute and retain heat |
| Non-Hygroscopic Glass Fiber Insulation | Reduces heat loss |
| Polymer Outer Jacket | Provides environmental and mechanical protection |
The outer jacket is available in ATP or TPU configurations.
Cut-to-Length HPT
A major advantage of HPT is its cut-to-length capability.
This allows the heat-tracing circuit to be manufactured or adjusted to the required length rather than being restricted to fixed cable lengths.
For tubing-bundle installations, this can simplify engineering and installation when the actual field routing varies from one application to another.
Thermon explicitly identifies “cut-to-length” as one of the main HPT product features.
Available Watt Densities
Thermon’s HPT specification identifies the following standard watt-density options:
- 5 W/ft
- 10 W/ft
- 15 W/ft
- 20 W/ft
Equivalent metric ratings are approximately:
- 16 W/m
- 33 W/m
- 49 W/m
- 66 W/m
These ratings are specified at the applicable reference temperature.
The appropriate watt density should be selected based on:
- Required maintenance temperature
- Minimum ambient temperature
- Tube size
- Insulation
- Bundle length
- Process conditions
- Installation environment.
Voltage
The standard HPT specification identifies nominal supply voltages from:
120 to 240 VAC
Thermon notes that higher voltages, up to 480 VAC, may be possible with engineering assistance.
Therefore, the electrical supply should be confirmed when specifying the complete TubeTrace assembly.
Hazardous Area Applications
TubeTrace with HPT is suitable for both:
- Ordinary / non-classified areas
- Hazardous / classified areas
Thermon’s HPT specification specifically states that HPT is approved for use in ordinary and hazardous areas.
The appropriate termination and connection system must be selected according to the hazardous-area classification.
Thermon provides installation documentation for both Division Classification and Zone Classification configurations, including Terminator and FAK connection systems.
TubeTrace HPT for Freeze Protection
In cold environments, instrument and process tubing can be exposed to freezing conditions.
Freezing can cause:
- Blocked tubing
- Instrument malfunction
- Process interruption
- Damage to tubing or components
- Incorrect analyzer measurements.
TubeTrace with HPT provides electrical heat to compensate for heat loss and maintain the tube above the required freeze-protection temperature.
This makes it particularly useful for outdoor installations and exposed process instrumentation.
High-Temperature Exposure Considerations
Thermon’s specification states that the HPT heater can withstand exposure up to 260°C (500°F).
However, Thermon also notes an important design consideration concerning the outer jacket and personnel burn risk. If the bundle jacket is required to remain below approximately 60°C (140°F) at an ambient temperature of 27°C (80°F), the tube temperature must remain below approximately 205°C (400°F) for the referenced design. Alternative designs are available for higher ambient or tube temperatures.
Therefore, the actual operating temperature should be established during the engineering stage rather than simply using the maximum heater exposure temperature.
TubeTrace with HPT vs. Constant-Watt Heating
| Feature | TubeTrace with HPT | Constant-Watt Heat Trace |
|---|---|---|
| Heating principle | Power-limiting | Constant output |
| Heat output | Changes with surrounding conditions | Relatively constant |
| Overheating risk | Lower | Potentially higher |
| Cut-to-length | Yes | Depends on product |
| Start-up current | Low | Application dependent |
| High-temperature capability | Yes | Depends on cable |
| Hazardous-area use | Available | Depends on product |
| Typical applications | High-temperature tubing, CEMS, analyzers | General heat tracing |
The reduced overheating risk and variable output characteristics are among the reasons Thermon positions HPT as a durable solution for high-temperature tubing-bundle applications.
Typical Applications
Thermon TubeTrace with HPT is suitable for:
Emissions Monitoring
- CEMS
- High-temperature emissions sampling
- Flue-gas analyzer systems
Process Analysis
- Process analyzer sample lines
- Gas analyzer systems
- Chemical analyzer systems
Instrumentation
- Instrument tubing
- Impulse lines
- Process sampling lines
Industrial Freeze Protection
- Outdoor instrument tubing
- Process tubing
- Tubing exposed to low ambient temperatures.
Thermon’s broader tubing-bundle portfolio includes TubeTrace configurations for analyzer sample lines, instrument tubing and high-temperature steam-line freeze protection.
Engineering Selection
When selecting a TubeTrace with HPT system, the following information should be considered:
- Process tube material
- Tube diameter
- Tube length
- Required maintenance temperature
- Minimum ambient temperature
- Maximum ambient temperature
- Required watt density
- Supply voltage
- Hazardous-area classification
- Required termination and connection kits
- Temperature sensor/control requirements
- Outer-jacket requirements
Correct selection of these parameters is essential for achieving the required temperature maintenance while keeping the tubing and outer jacket within their allowable temperature limits.
Technical Specifications
| Attribute | Specification |
|---|---|
| Brand | Thermon |
| Product Family | TubeTrace® |
| Heat Tracing | HPT™ Power-Limiting |
| Product Type | Electrically Heated Tubing Bundle |
| Application | Freeze Protection / Temperature Maintenance |
| Maintenance Temperature | 5°C to 177°C |
| HPT Exposure Temperature | Up to 260°C |
| Watt Density | 5 / 10 / 15 / 20 W/ft |
| Metric Watt Density | 16 / 33 / 49 / 66 W/m |
| Nominal Voltage | 120–240 VAC |
| Higher Voltage | Up to 480 VAC may be possible with engineering |
| Heat Tracing Type | Power-Limiting |
| Cut-to-Length | Yes |
| Start-Up Current | Low |
| Insulation | Non-Hygroscopic Glass Fiber |
| Outer Jacket | ATP / TPU |
| Hazardous Area | Available |
| Applications | CEMS / Process Analyzer / Instrument Tubing / Freeze Protection |
Specifications are based on Thermon’s HPT product specification and current TubeTrace product page.
Why Choose Thermon TubeTrace with HPT?
Thermon TubeTrace® with HPT™ combines the flexibility of an electrically heated tubing bundle with the advantages of power-limiting heat tracing.
Its ability to provide freeze protection and temperature maintenance, withstand high-temperature exposure, be cut to length, and operate in hazardous-area environments makes it especially suitable for CEMS, process analyzer and high-temperature instrument tubing applications.
For demanding industrial applications, the system provides a practical way to integrate process tubing, electrical heating, insulation and environmental protection into one engineered assembly.
