Parr Instrument Series 4520 - Manual (Page 10)

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4520 Bench Top Reactors Parr Instrument Company
IDENTIFY THE VALVES
Gas Release Valve
The gas release valve is mounted on an
extension in a 1/8” NPT port. This valve is
open to the gas head space of the cylinder.
This position also includes a 1/8” NPT
thread on the underside of the head which
may be used for a second dip tube or an
alternate accessory such as a catalyst
addition device.
Note: If a fitting is added to the
underside of the head in this location it will
be necessary to install an additional valve
on the gage adapter open to the gas space
of the vessel for pressure release.
Gas Inlet Valves
The gas inlet valve is easily identified
when the vessel is open by noting that it is
connected to a dip tube which extends to a
point near the bottom of the cylinder. This is
an angle pattern valve with an attached
coupling which provides a socket for
attaching the A495HC gas hose furnished
with the reactor.
Liquid Sampling Valve
The liquid sampling valve is attached to
the same adapter as the gas inlet valve
combined with the dip tube. With this
arrangement, incoming gas is always
introduced below the surface of the liquid
and the operator is provided with a means
for clearing the dip tube to be sure that any
sample taken during a run will be
representative of the charge. This can be
done by opening the gas valve momentarily
to force any liquid in the tube back into the
reactor before withdrawing a sample from
the sampling valve.