Instruction Manual

Fulton Thermal Corp.*SteamPac Unfired Steam Generators Manual* Version 2010-0201
Page 29
c) Hot oil pipe insulation should be a minimum of 2” thick, high temperature, laminated,
foamglass cellular glass insulation as manufactured by Pittsburgh Corning Corporation,
or equal.
23. Thermal Fluids
Thermal Fluids at Elevated Temperatures
a) Plant engineers must be familiar with the nature of potential hazards when working with
thermal fluids at operating temperatures.
b) Unlike steam or high-pressure water systems, thermal fluid attains extremely high
temperatures without a corresponding increase in pressure. While this lack of high
pressure in the system yields many advantages, a false sense of security should not be
allowed to develop on account of this alone.
c) Certain types of thermal fluid may have operating temperatures reaching 650°F (345°C)
and above, so all exposed pipework is hazardous and should be insulated, as indicated
in the preceding sections.
d) Flanged joints must be checked for tightness during and after the first warming up of the
system. After these checks, exposed hot flanges, pumps, valves and fittings should be
fitted with some sort of shield.
e) It is important to remember that there is pressure generated in the system by the
circulating pump. Great care should be exercised when opening any drain or vent valves
in the system.
d) This is especially important during commissioning, when any air trapped in the system is
vented at high points, and when water, which will flash into steam, is either expelled from
the deaerator vent or drained off at low points.
Caution
During operation, any leaks are usually detected by a small amount of vapor.
Leaks should be attended to as soon as possible because under certain
circumstances, such as saturated insulation, thermal fluid can ignite when
exposed to air and heat.
e) If a fire does occur, extinguish using CO
2
, foam or dry chemical. DO NOT USE WATER.
f) Selecting a Thermal Fluid
1. The selection of the thermal fluid most suited to your application is very
important. Factors to be considered include efficiency,
thermal stability, adaptability to various systems, and physical properties,
including vapor pressure, freezing point, and flash and fire points.
2. Heat transfer fluids of both mineral and synthetic origin have been
specially developed to give thermal stability over a very wide range of