Parr Instrument Series 4570 - Manual (Page 12)

- 12 -
4570 HP/HT Pressure Reactors Parr Instrument Company
HOW TO USE THE VESSEL
Fixed Head Vessels:
First, lower the heater and push it to the
side. Before attempting to remove the split
ring open the gas release valve to discharge
any internal pressure. Raise the cylinder
support holder to the bottom of the cylinder
using the pneumatic lift as described on page
15 of this manual.
The head with any attached connection
lines will remain in place.
Moveable Head Vessels:
First, open the gas release valve to
discharge any internal pressure. This vessel
can remain in the heater when attaching or
removing the split ring closure. The head
assembly can be removed from the cylinder.
Handle the head carefully so that no damage
will occur to any of the internal fittings.
To open the Vessel
Loosen the bolts in a criss-cross pattern
reversing the tightening procedure, gradually
decreasing the torque on each bolt.
Before closing the Vessel
Examine the head seal carefully to be
sure that it is in good condition. The seal
should not have any nicks, be hardened or
deformed. Also examine the mating surfaces
on the head and cylinder to be sure they are
clean and free from burrs.
To Close the Vessel
Place the two split ring halves around the
head and cylinder flanges. Close the latches
on the fixed head split ring.
Attach the anti-rotation clamp on the
moveable head split ring.
A torque wrench is furnished with these
vessels and it includes an adapter for the 12
point heads of the bolts used in these split
rings. The amount of torque to be applied will
depend upon the intended maximum
operating pressure. To ensure a good seal
over the full operating range apply the
recommended bolt torque per the table
below.
Recommended Bolt Torque:
PTFE 2100 PSI 25ft-lbs
PTFE or Flexible
Graphite 4000 – 6000 PSI 40 ft-lbs
Pick a starting bolt and tighten it to
approximately 15 ft-lbs. Then by-pass the
adjacent bolts and move around the closure
to a bolt approximately 180 degrees from the
starting bolt. Torque all bolts to the initial 15
ft-lbs. Then proceed with the same pattern
increasing the torque in 10 ft-lbs increments.
Note: Flexible graphite gaskets tend to be
somewhat flakey. To extend the useful life of
these gaskets, first rough up the sealing
surface of the cylinder with 120 grit sand
paper to insure the gasket remains in the
head groove and does not stick to the
cylinder. Secondly, coat both sealing
surfaces with a silicone lubricant. This
process will aid in compressing the gasket so
it does not break apart after one use.
Gas Connections
Gas connections are dependent on
applications. For most applications, the
hose furnished with the system is sufficient.
Attach 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 or PTFE tape
on the coned fitting.