Thermal Management Materials

Temperature control is inescapable in any industrial process. Numerous specifications must be analyzed to discover the best solution for any particular design. Central to any thermal solution will be the tubing that is responsible for transporting the temperature-dependent media through a system as well as providing heat exchange. To that end, hoses, tubing, and any surrounding insulation are the components most immediately responsible for maintaining temperature control from end to end. 

Tubing and installation have a long service when properly installed. When looking to invest in thermal management materials, it’s necessary to consider how thermal concerns tie into hose and insulation design.

Hoses: The Heart of Thermoregulation

The Need

For industries interested in fugitive emission reduction, hose properties are important—especially as permeation trends upwards at elevated temperatures. Because the hose is in continuous direct contact with the heated or cooled media, it must be durable enough to withstand the extreme temperature environment. Multiple material properties will change when exposed to high or low temperatures, and operations not only need to be concerned with the hose itself, but any fittings, unions, and other components to which it may be attached. The dynamism of a tube may also be noteworthy, as a sudden increase in temperature could result in damage to operators, nearby equipment, or the tube itself. 

The Solution

Swagelok’s stainless steel braided FX hose series is a great line for catch-all temperature needs in low-vibration settings. With a temperature range from -328°F to 998°F (-200°C to 537°C), they are able to cover a vast amount of thermal industry processes. Of course, for any high-temperature environment, high pressure is an equal concern due to their direct proportionality. 

To protect operators and equipment, the FX series contains multiple high-pressure design elements. An all-metal hose, as well as 316L convoluted core and 321 double-braided stainless steel provide additional pressure containment capabilities. With working pressures up to 6000 PSIG and a wide range of sizing from 6.5 to 51 mm, the FX series are an excellent choice for high- and low-temperature media.

Insulation: Thermal Management Materials’ Key Contributor

The Need

Insulation is as critical as the tubing itself in any thermal application. Without suitable insulation, media temperature misses its targeted value. A carefully calibrated reaction will certainly take a hit in efficiency, but the effects cascade much further beyond that. Safety, whether directly from burns or indirectly from slip and fall hazards due to condensation, is at risk. Industries with closely-monitored emission standards are now faced with investing more energy into heating and cooling fluids with lines that span the length of a facility. The financial hit could be a double-whammy, as heating/cooling costs increase with the added potential of hefty regulatory fines and lost product due to inefficiency.

The Solution

Below is just a few of the considerations for insulation, as well as design constraints to maximize thermal efficiency:

• Free air convection: Issues may arise when routing thermal lines too close. Cold lines could cause a buildup of condensation due to a drop below the dew point. Hot lines can form hot spots above the max operating temperatures of the material, possibly creating failure points. In general, as the normal distance between the surface of the hoses drops, the ambient temperature more closely resembles the interior temperature of the hoses. For best practices, either allow a minimum distance of 31 cm or increase insulation if system constraints do not allow for an increase in distance.
• Air flow: Air flow and heat transfer coefficient share a positive relationship: the greater the air flow, the greater the heat transfer potential (and vice versa). In heavily confined spaces with restricted air flow, this can result in issues, such as condensation forming on a cooling line and shorting electronics below it.   
• Dew point: Determining the amount of insulation to prevent condensation can be modeled by an approximate dew point calculation: 

TD = T - [(100-RHMAX)/5]  

T_D, T, and RH_MAX represents the dew point temperature in Celsius, ambient air temperature in Celsius, and expected max relative humidity as a percentage, respectively.

• Savings: Compared to uninsulated tubing, insulation can reduce energy losses by up to 90%. This has the added benefit of reducing energy usage, thereby reducing HVAC costs.
• Safety: Insulated tubing protects operators from extreme temperatures that could cause burns. Depending on material, for heated lines, the American Society for Testing and Materials C1055 guidelines call for hard surface temperatures to remain at or below 140°F (60°C) and at or below 194°F (90°C) for soft materials to prevent burns.
• Bends: A design may necessitate a bend in a thermal line. While the tube’s properties will not change, insulation on the inside and the outside of the bend may exhibit different insulation capabilities than expected. On the outside of the bend, the insulation is placed in tension and is drawn thinner as it covers a longer distance. Meanwhile, the insulation on the inside of the bend is compressed and covers a shorter distance. To rectify, larger bend radii should be employed to lessen the effects. For situations where small bend radii are required, additional insulation can be added to the hose while held in a bent shape to accommodate the severe routing. 

For hoses and tubing, the Y insulation option provides a wide operational temperature range of -63.4°F to 257°F (-53°C to 125°C). An aerogel reduces bulk from insulation while providing excellent low thermal conductivity, while a heat shrink cover provides seals effectively against vapor permeation and prevents outside abrasions.

Thermal Management Materials From Swagelok Northern California Can Help You Keep Your Cool

When you’re addressing thermal management in your industrial system, let a Swagelok Northern California Field Engineer work with you to provide the best solution. Our catalog contains numerous sizes, styles, and thermal management materials to cover any process you may encounter. 

Swagelok’s insulated tubing is designed for use in applications such as steam supply, condensate return, and gas and liquid transport lines, where weatherproofing and energy conservation are important. It helps protect personnel from hot process and steam lines, reduces heat loss, and offers a cost-effective alternative to field-installed insulation of small-diameter tubing systems.

If you have any questions about a configuration not covered within our product lines, Swagelok Northern California provides customizable options for special hose, tubing, or other thermal needs.

To find out more about how Swagelok Northern Californiacan provide customized thermal management solutions, contact our team today by calling 510-933-6200.