parr 4520, Operating Instructions Manual, Page: 6 / 32

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4520 Bench Top Reactors
Parr Instrument Company
INSTALLATION
Pressure and Temperature Limits
The working pressure and temperature at
which any reactor or pressure vessel can be
used will depend upon the design of the vessel
and the materials used in its construction.
Since all materials lose strength at elevated
temperatures, any pressure rating must be
stated in terms of the temperature at which it
applies. The standard material of construction
for Parr Instrument Company is Type 316
Stainless Steel.
Limits for vessels made of other materials
and for other operating temperatures can be
obtained from Parr Customer Service. No
attempt should be made to increase these
limits by making alterations or by substituting
components that are not recommended by
the Parr Instrument Company. It must also
be understood that lower pressure and
temperature limits may be required for
modified reactors and for vessels made of
special alloys.
Limits for vessels will be determined by
the physical characteristics of the vessel
material and will be prescribed on an
individual basis.
The maximum working pressure and
temperature for any vessel is governed by
the design of the vessel and the strength of
the material from which it is constructed.
There is also a close relationship between
working pressure and temperature since the
strength of any material will normally fall off
as the temperature is increased.
Temperature and pressure limits are also
affected by the physical properties and
temperature limits of the gaskets and seals
used in the vessel, and by any valves,
gages or other fittings attached to the
vessel. Obviously, the safe operating
pressure of any system can be no higher
than that of its lowest rated component.
All Parr reactors show the maximum safe
operating pressure and temperature
imprinted on the cylinder.
The working pressure and temperature in
these one and two liter reactors must not
exceed the following maximum limits:
Pressure and Temperature Limits
Vessel
Material
Maximum
Pressure Maximum
Temperature
T316SS 1900 psig 350

C PTFE Flat
Gasket
T316SS 1900 psig 225

C FKM O-ring
T316SS 1900 psig 275

C FFKM O-ring