Mobiltherm® heat transfer oils should not be mixed with other oils as this can compromise their excellent thermal and oxidation stability resulting in a change in other properties and complicate analyses to determine useful oil life. If the oil is operated above the recommended operating temperature, a gas bubble may form unless the equipment is designed to operate at a higher temperature by pressurisation with an inert gas such as nitrogen.
Description
Mobiltherm® 611: Gesloten systemen (tot 315º C), Open systemen (tot 180º C)
Mobiltherm® heat transfer oils should not be mixed with other oils as this can compromise their excellent thermal and oxidation stability resulting in a change in other properties and complicate analyses to determine useful oil life. If the oil is operated above the recommended operating temperature, a gas bubble may form unless the equipment is designed to operate at a higher temperature by pressurisation with an inert gas such as nitrogen. At higher temperatures, the life of the oil is shortened because thermal degradation increases significantly as temperatures rise above the recommended limit. In a well-designed installation, the temperature of the oil film in the heating element should be kept approximately 15°C to 30°C above the bulk oil temperature. Higher temperatures will shorten the life of the oil and may lead to sludge and coke formation which can impede heat transfer. As with other mineral oils, Mobiltherm® heat transfer oils should be used only in systems equipped with a circulation pump. Systems in which only convection moves the oil do not provide sufficient flow to prevent local overheating and rapid oil deterioration. Furthermore, these oils are not recommended for use in open installations where hot oil is in direct contact with air.