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Thermal fluid systems play an extremely important role in various industrial applications, because they can provide efficient heat transfer in processes that need high temperatures. To make sure these systems keep performing optimally and safely, it is essential to follow best practices during the initial installation and day-to-day operation. Here are HEAT’s recommendations and key concerns for installing and maintaining thermal fluid systems:

1 - Choosing Suitable Materials:

When installing thermal fluid systems, it is crucial to select appropriate materials that can withstand the demands of the system and application. Seamless carbon steel pipe with welded or flanged connections are recommended for piping, as they provide durability and reliability. Also, non-wicking cellular glass insulation should be used to insulate the pipes of your hot oil system – this ensures efficient heat retention and prevents dangerous fire hazards of oil-soaked insulation.

2 - High Point Vents and Low Point Drains:

High point vents help with the removal of air during the commissioning process, preventing pump cavitation and making sure the system operates smoothly. Low point drains are useful for both filling and draining fluid at different locations - especially in complex piping systems - simplifying maintenance and troubleshooting procedures.

Watch: Hot Oil System Installation Best Practices

Installing a Hot Oil System into your process can give you precise temperature control exactly where you need it, but there are important installation and safety considerations to think about before you're able to start using the equipment.

Join John Kelly, Jr. as he talks about the critical steps you should take before turning your hot oil system on. 

Watch on YouTube

3 - Instrumentation for Monitoring:

Incorporating instrumentation into the piping system is highly advantageous. Instruments can serve multiple purposes, including providing a quick visual check of system performance once it is balanced and operational. They also assist in troubleshooting potential issues. While budget constraints may limit the extent of instrumentation, it is recommended to include it wherever possible for enhanced monitoring capabilities.

4 - Pressure Testing:

During the installation of thermal fluid systems, pressure testing is essential to ensure the integrity of the piping. It is crucial to avoid using water while testing pipes for oil service, as any water left inside the piping can lead to significant problems. Instead, gases such as nitrogen or dry compressed air are recommended for pressure testing, as they pose no risks of trapping water vapor inside the system at elevated temperatures.

5 - Expansion Tank Volume:

The expansion tank plays a vital role in accommodating the thermal expansion of the thermal oil. Calculating the required expansion volume based on the properties, volume, and operating temperatures of the fluid is crucial. It is generally recommended to include an expansion tank with a capacity at least twice as big as this calculated volume of expansion. Learn more about expansion tanks here.

6 - Expansion Tank Placement:

Proper placement of the expansion tank is critical for system efficiency and safety. It should be top-mounted or remotely mounted at the highest point in the closed-loop process, ensuring proper venting and eliminating air lock when the system is being filled or running. If the piping extends higher than the tank, it may be necessary to relocate the tank to a high point and connect it to the system with a connector pipe. However, it is crucial to make sure that the pipe connecting the expansion tank to the system has no restrictions, check valves, or isolation valves that could potentially isolate the electric heater from the vented tank. Such isolation poses a serious safety concern.

If you keep these things in mind as you're installing and using your hot oil system, you're well on your way to making sure that your workers and your process are safe, even around the high temperatures that manufacturing applications can have. If you have any questions, our experts are always happy to help.