The Paratherm OR® sludge-resistant heat transfer fluid combines substantial oxidation resistance with excellent thermal efficiency, high flash and fire points and extended service life.  This zero-pressure fluid provides precise, uniform temperature control to 550°F in closed-loop thermal oil systems where the heat transfer fluid is more than occasionally exposed to air.  The crystal-clear OR fluid is comprised of a unique high-stability base plus high-performance oxidation inhibitor/stabilizer. Performance of the OR fluid is particularly impressive under the same grueling conditions that quickly cause severe oxidation, fluid breakdown and sludge formation in conventional heat transfer fluids.

Oxidation

Heavy fluid oxidation occurs when supplies of fresh air come into intimate contact with hot heat transfer fluid (during frequent tool changeout, for example). The resulting reaction converts fluid molecules to organic acids. Soon the acids themselves begin to degrade thermally. The fluid becomes thicker, darker and more odorous, and its heat transfer capabilities drop dramatically.

Fouling

As an oxidized fluid becomes more viscous, it becomes more difficult to pump and more susceptible to overheating. Remaining in contact with the heated surfaces too long, the fluid picks up more heat than its chemical bonds can stand.  As they break down, the fluid's molecules release their carbon forming an acidic, carbonaceous sludge that precipitates out and adheres to the system's interior surfaces. Much of this sooty, sticky carbon bakes on to the heated surfaces where it was produced.  The OR fluid contains an additive system that inhibits sludge and carbon formation. Even under prolonged exposure to air, the fluid won't foul heated surfaces.

Efficiency

Due to its low viscosity, the OR fluid provides unusually high thermal efficiencies — higher than most synthetics. The lower in viscosity (the thinner) a heat transfer fluid is, the less energy is required to pump it through the system. In addition a smaller pump and motor can be specified, and the lower power consumption will continue to produce savings year after year. 

Environmental Safety

In the event of a release, the same simple clean-up procedures used for light lubricating oils can be employed. Once gathered, the OR fluid can be combined with spent lube oils and sent to the local oil recycler. The crystal-clear Paratherm OR fluid contains no chlorinated or aromatic hydrocarbons, heavy metals, or sulfur or nitrogen compounds.

Fluid Toxicity

The Paratherm OR fluid is non-toxic and non-hazardous.  If the fluid is ingested in any quantity, it may act as a laxative. We strongly recommend that you do not breathe vapor mists of any fluid.  See the Material Safety Data Sheet for further information on these, and other conditions.

Vapor Pressure

The OR fluid has extraordinarily low vapor pressure — a fraction of an atmosphere at its maximum operating temperature of 550°F — thus expensive system pressurization is not required. Low vapor pressure combined with the fluid's exceptionally low pressure drop permits the designer broader latitude in the choice of lower-cost equipment.

Corrosion

The OR fluid is manufactured from natural US feedstocks and offers the same superb metal-coating and lubricating properties as the finest natural oils. The corrosion and wear common with steam and water systems rarely occurs in thermal oil systems containing Paratherm heat transfer fluids. Chemically inert, the Paratherm OR will not attack high temperature seals and gasketing.

Water in the System

Because the OR fluid is immiscible with water and is slightly less dense, system water can be easily removed via the system's low point drain valves. Crack each low-point valve and allow fluid to drain into a beaker or clear water glass. If you see a phase separation (one liquid "floating" on top of the other), continue to drain until no separation is observed.

Storing Your Fluid

Containers of heat transfer fluid should be kept in non-hazardous dry areas only. Until ready for use, the container's tamper-evident safety seals must remain intact. Liquids should not be allowed to pool on the tops of steel drums. In the afternoon and evening when temperatures decrease, the heat transfer fluid will cool and contract slightly. A partial vacuum is created in the drum. If the bung's elastomeric seal is not perfect, liquid standing on the top of the drum can be drawn through, contaminating the fluid. If drums must be temporarily stored outside, store them on their sides.

Pre-Cleaning the System

For optimal performance of your system and its heat transfer fluid, thoroughly clean all piping, valves and components before installation. Mill scale, weld spatter and slag, quench oils, protective lacquer and varnish coatings, and dust and dirt will degrade the fluid, and can damage pumps and valves. Lodging in restrictions, these contaminants can easily create low-flow conditions that cause premature failure of systems and fluid.

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