2.4.4 Recovery of liquid in sample cell to Vessel 1
The liquid in the sample cell cannot be recovered to Vessel 1 using the liquid
handling rig as presently configured.
2.4.5 Recovery of liquid in sample cell to Vessel 2
The liquid in the sample cell can be recovered to Vessel 2 using the following
procedure.
•
Vessel 2 should be under vacuum along with the manifold between valves V5
and V6 prior to the recovery of the liquid from the sample cell. If it is not,
switch the pump to roughing mode and open tap E and valve V7 followed by
valves V1 and V2. If Vessel 2 already contains some liquid, ensure that it is
frozen using liquid nitrogen before evacuation is attempted.
•
When the vessel and manifold have been evacuated, close tap E and cool the
glass bulb by raising a dewar of liquid nitrogen around it.
•
Ensure that tap E and valves V6 and V8 are closed before attempting to open
valve V5.
•
Opening valve V5 will allow the liquid present in the sample cell to be drawn
into Vessel 2 where it will freeze.
•
All the liquid may not return in a single pass and repeating the evacuation
procedure may be required. The liquid may also be encouraged to leave the
sample cell by using a small amount of gas.
•
Close valve V3 and open valve V9 to allow helium gas into this part of the
system. Close valve V9 and carefully open valve V4 to allow the gas to enter
the sample cell. DO NOT repeat this procedure until the pressure in the
system is known by opening tap E.
•
Close valve V7 and re-pressurise the system and Vessel 2 by opening valve
V9 and tap E.
2.4.6 Recovery of liquid in sample cell to Vessel 3
The liquid in the sample cell can be recovered to Vessel 3 using the following
procedure.
•
Vessel 3 should be under vacuum prior to the recovery of the liquid from the
sample cell. If it is not, switch the pump to roughing mode and open tap C
and valve V3 followed by valves V1 and V2. If Vessel 3 already contains
some liquid, ensure that it is frozen using liquid nitrogen before evacuation is
attempted.
•
When the vessel and manifold have been evacuated, close valve V3 and cool
the glass bulb by raising a dewar of liquid nitrogen around it.
•
Ensure that tap D and valves V6, V7 and V8 are closed before attempting to
open valve V4.
•
Opening valve V4 will allow the liquid present in the sample cell to be drawn
into Vessel 3 where it will freeze.
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