Heat transfer fluids, sometimes referred to as thermal oils, are designed to carry thermal energy in machine cooling, metalworking and process heating applications. Multiple products exist, including circulating coolants, anti-freezes, chiller fluids and refrigerants that are utilised to either provide cooling or to transfer heat inside machinery, combustion engines or process equipment. However, heater oils, among other types of thermal fluid, are used to transfer or provide heat to a specific region near process equipment or machinery.
Usually, products like refrigerants, anti-freezes and hot oils deliver indirect cooling or heating and never come into direct contact with the equipment or machinery. In contrast, quenchants and other metal working fluids contact components or workpieces directly. Thermal oils and heat transfer fluids are often employed in chillers, coolers and circulating process heaters. Primary refrigerants deliver cooling through phase changes that consists of both heat transfer and evaporative cooling.
Heat transfer oil specifications
Thermal oils and heat transfer fluids can vary greatly in their chemical composition. For example, synthetic products will include diester and ester compounds, water-glycol and polyglycol fluids, and oils and greases that are silicone-based. They are usually formulated using inorganic and alkaline organic compounds and diluted before use with concentrations that range between 3 to 10 per cent.
Non-synthetic solutions consist of mineral and petroleum oils and may sometimes include water. As a rule, synthetic products are usually more expensive to buy than non-synthetic options, but they provide enhanced qualities for both cooling performance and fire resistance. The heat transfer and cooling performance of semi-synthetic solutions falls between those offered by soluble oil and synthetic fluids.
Heat transfer oil applications
Thermal oils and heat transfer fluids are used in an extensive variety of industries and applications. Some available options are employed in aerospace, marine, automotive and even military applications. However, others are utilised with processing equipment, combustion engines, compressors, gears and piston pumps, as well as final drives.
Custom-designed thermal oils and heat transfer fluids are also designed to offer a range of additional attributes that can prevent or inhibit or prevent corrosion, microbial growth and oxidation. Biodegradable products are also offered that can break down to become harmless chemicals to reduce their impact on environment when released.
Finally, for use in the pharmaceutical and food and beverage manufacturing industry, heat transfer oils are also engineered that have applicable safety ratings to adhere with regulations.