Parr Instrument Series 4558 - Manual (Page 17)

4555 - 58 Series
5G & 10L Pressure Reactors
- 16 -
Close the Vessel
For removable heads, lift the head carefully from its service position and lower into the
cylinder. Slide the two split ring sections into place. Tighten each of the compression bolts
with the wrench furnished with the apparatus or with a torque wrench. Tightening should
proceed in a crisscross pattern rather than progressively around the circle. Let the vessel
stand for about five minutes after initial tightening; then tighten the cap screws again. This
will compensate for any tendency of the PTFE gasket to flow under the loading pressure.
The recommended bolt torque for sealing a vessel with a PTFE flat gasket is shown in
the chart below. Rotate the drive into position. Connect the drive by pushing up on the lower
coupler halve to engage it into the spider. Make sure the ball detent of the lower coupler
snaps into position.
For fixed heads, raise the cylinder slowly and carefully in to position. Slide the two split
ring halves into place and secure the latches. Tighten the compression bolts in the same
manner as noted above.
Recommended Bolt Torque
10 Liter
Pressure
(psi)
Torque
(ft-lb)
500 psi
1000 psi
1500 psi
1900 psi
25
50
75
100
Recommended Bolt Torque
5 Gallon
Pressure
(psi)
Torque
(ft-lb)
500 psi
1000 psi
1500 psi
1900 psi
35
70
100
135
Gas Connections
Gas connections are dependent on applications. For general usage, use the pressure
hose furnished with the reactor. Screw the Type "A" coned pressure fitting into the adapter
attached to the gas inlet valve and tighten the compression nut firmly. Do not use any
thread dope on the coned fitting. The A495HC pressure hose is made of reinforced Nylon
which can be used for all non-corrosive gases at pressures up to 2500 psig. For operations
involving corrosive gases, this hose should be replaced with an A490HC hose which has a
PTFE lining and a braided stainless steel outer covering. An A506HC all metal hose is also
available in stainless steel and other corrosion resistant materials. All of these hoses have
the same fittings.
Pressurizing the Vessel
Check all valves carefully before admitting gas into the system. The liquid sampling
valve must remain closed throughout the charging procedure. The gas release valve must
also be closed unless the vessel is to be purged, or unless there is to be a continuous flow
through the reactor during a run. Always make certain that the pressure in the gas tank is
greater than the pressure in the vessel; otherwise liquid will be forced out of the vessel and
into the gas tank when the inlet valve is opened. If there is any possibility that the tank
pressure might not be high enough to force gas into the reactor, install a one way check
valve (optional) in the gas line to prevent any reverse flow. With the inlet valve open and the