Description
Thermon ThermoTube® Type SL – HT, HTX & HTX2
High-Temperature Pre-Insulated Tubing for Extreme Industrial Applications
Thermon ThermoTube® Type SL – HT, HTX & HTX2 is a family of high-temperature pre-insulated single-tube bundles engineered to transport steam, hot liquids, process fluids, sample lines, and instrument impulse lines where conventional insulated tubing cannot withstand elevated temperatures. These tubing bundles are non-heated and are intended for applications where heat tracing is unnecessary, such as indoor installations or environments that do not experience freezing conditions. Their advanced insulation system minimizes heat loss for energy conservation while maintaining a touch-safe outer jacket to improve personnel protection.
Designed for refineries, petrochemical plants, power stations, and heavy industrial processes, the HT Series extends the operating capability of the standard ThermoTube® Type SL to process temperatures as high as 593°C (1100°F).
Product Overview
The ThermoTube Type SL High-Temperature Series is available in three configurations:
- SL-HT – Continuous service up to 399°C (750°F)
- SL-HTX – Continuous service up to 593°C (1100°F)
- SL-HTX2 – Intermittent exposure up to 593°C (1100°F) (up to 2 minutes per cycle)
Each bundle is factory-manufactured using multiple insulation layers and a durable polymer outer jacket, providing consistent thermal performance and significantly reducing field installation time compared with conventional site-insulated tubing.
Key Features
- Factory pre-insulated single-tube bundle
- Designed for high-temperature steam and liquid transport
- Suitable for sample lines and instrument impulse lines
- Continuous service up to 593°C (HTX)
- Excellent energy conservation through reduced heat loss
- “Touch Safe” outer jacket helps protect personnel
- Supplied in cut-to-length coils for faster installation
- Available with ATP or TPU outer jackets
- Compatible with Thermon tubing bundle accessories
- Long service life with minimal maintenance requirements.
Construction
ThermoTube Type SL – HT, HTX & HTX2 uses a multi-layer insulation system specifically engineered for extreme temperatures:
- Process Tube
- High-Temperature Woven Glass Fiber Thermal Insulation
- Thermal Diffusion Foil
- Heat Reflective Foil
- Non-Hygroscopic Glass Fiber Insulation
- ATP or TPU Polymer Outer Jacket
This layered construction reduces heat loss while keeping the external jacket temperature significantly lower than the process temperature, improving both energy efficiency and operator safety.
Available Tube Materials
ThermoTube can be manufactured using numerous tubing materials to meet demanding process requirements, including:
- 304 Stainless Steel
- 316 Stainless Steel
- Alloy 825
- Alloy C276
- Alloy 20
- Monel®
- Titanium
- Special alloy materials upon request
Available tube sizes include:
- 1/4″
- 3/8″
- 1/2″
with several wall thickness options depending on pressure and process requirements.
Technical Specifications
| Feature | SL-HT | SL-HTX | SL-HTX2 |
|---|---|---|---|
| Maximum Process Temperature | 399°C (750°F)Continuous | 593°C (1100°F) Continuous | 593°C (1100°F) Intermittent* |
| Bundle Diameter | 76 mm | 89 mm | 58 mm |
| Minimum Bend Radius | 406 mm | 508 mm | 305 mm |
| Outer Jacket | ATP / TPU | ATP / TPU | ATP / TPU |
| Application | High-temperature transport | Extreme continuous temperature | High-temperature intermittent exposure |
*Intermittent exposure is rated for up to 2 minutes per heating cycle.
Product Benefits
Extreme Temperature Capability
The HT Series extends the operating range of ThermoTube well beyond conventional pre-insulated tubing, making it suitable for process temperatures approaching 600°C.
Energy Conservation
High-performance insulation minimizes thermal losses, reducing energy consumption while maintaining process temperatures.
Personnel Protection
The engineered insulation system is designed to keep the external jacket significantly cooler than the internal process temperature, reducing the likelihood of accidental contact burns under the specified design conditions.
Faster Installation
Factory-insulated tubing bundles eliminate the need for field insulation, reducing installation time and improving installation quality.
Long-Term Reliability
The insulation system resists moisture ingress and maintains consistent thermal performance in harsh industrial environments.
Applications
ThermoTube Type SL – HT, HTX & HTX2 is widely used in:
- Steam supply lines
- Superheated steam systems
- High-temperature liquid transfer
- Process sampling systems
- Instrument impulse lines
- Refineries
- Petrochemical plants
- LNG terminals
- Chemical processing facilities
- Power generation plants
- Offshore platforms
- Steel mills
- Industrial furnaces
These tubing bundles are especially valuable where high process temperatures are required but electrical or steam heat tracing is unnecessary.
HT vs HTX vs HTX2
| Feature | HT | HTX | HTX2 |
|---|---|---|---|
| Maximum Continuous Temperature | 399°C | 593°C | — |
| Maximum Intermittent Temperature | — | — | 593°C (2 min/cycle) |
| Typical Application | High-temperature steam | Very high-temperature continuous service | High-temperature cyclic service |
| Bend Radius | Standard | Largest | Smallest (most flexible) |
Installation
ThermoTube bundles are supplied in continuous lengths and can be installed on:
- Pipe racks
- Cable trays
- Structural steel
- Utility corridors
- Process skids
Thermon offers a complete range of accessories including:
- FAK End Seal Kits
- Bulkhead Entry Kits
- Inline Splice Kits
- Heat Shrink Seal Kits
- Mechanical Tubing Bundle Benders
to simplify installation and provide long-term environmental sealing.
Why Choose Thermon ThermoTube® Type SL – HT, HTX & HTX2?
ThermoTube Type SL – HT, HTX & HTX2 provides an engineered solution for transporting high-temperature process fluids while reducing heat loss, improving personnel safety, and simplifying installation. With continuous operating temperatures up to 593°C, these tubing bundles are ideal for the most demanding industrial applications where conventional insulated tubing is inadequate.
Whether used for superheated steam, high-temperature liquid transfer, or instrument tubing in harsh environments, the HT Series delivers exceptional thermal performance, durability, and reliability across the oil & gas, petrochemical, power generation, and process industries.
