Thermal Oil is an excellent heating medium with a high thermal transfer power at low pressures and is widely used in heating processes at plastics transformation, rubber, plywood, lube equipment and boilers. Bellow sealed globe valves are recommended to combat atmospheric leakage through the gland and also metal sealing given the high temperature service, for example, triple offset butterfly valves.
Heat transfer fluids are featured by being a liquid medium at high temperature and low pressure thus being quite useful for applications as above mentioned.