Parr Instrument Series 4520 - Manual (Page 20)

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4520 Bench Top Reactors Parr Instrument Company
GENERAL MAINTENANCE NOTES
1. Periodically inspect all electrical wiring
and pressure connections for excessive
corrosion. Suspect parts should be
replaced by components only supplied
by Parr Instrument Company.
2. Always use appropriate wrenches on all
fittings and valves. Never use pliers or
pipe wrenches.
3. Head and cylinder service fixtures are
available for convenience and protection
of components during maintenance of
your reactor.
4. To reinstall straight thread (NPS) fittings
to the head, screw the gage or valves
firmly into the adapter.
Run the bushing onto the threaded stem
as far as it will go. Screw this assembly
into the head until the nose of the
adapter is seated; then back it off until
the valve or gage is facing in the desired
direction (no more than one full turn).
Hold the fitting firmly in place and close
the joint by tightening the bushing. This
connection can be made and broken
repeatedly without destroying the sealing
surfaces. A light coating of thread
lubricant, such as Parr High Temperature
Anti-Seize Lubricant, applied to the
straight threads and to the nose of the
adapter will help to obtain a tight joint.
Note: PTFE tape should not be used on
this joint.
5. NPT (National Pipe Taper) threads
should not be disassembled any more
than necessary. It will become
increasingly difficult to maintain a tight
seal with these tapered threads if the
joint is made and broken repeatedly.
Grafoil tape or PTFE tape (if temp
allows) should be used on all NPT
threads.
6. Do not use oil or anti-seize lubricant on
threads or fittings if the vessel is to be
used with oxygen.
7. If your vessel is equipped with a loose
compression ring be sure that it is in place
on the head before attaching any head
fittings. The compression ring cannot be
installed after fittings have been screwed
into the head.
8. Clean all threads and gas passages
thoroughly and remove all tape fragments
when overhauling a vessel. An ultrasonic
bath is excellent for cleaning metal parts,
but do not place a thermocouple probe,
pressure gage, face seals or ball bearings
in an ultrasonic bath. Periodic cleaning
may be performed on the exterior
surfaces of the reactor stand with a lightly
dampened cloth containing mild soap
solution. All power should be
disconnected when cleaning.
9. Routinely inspect cap screws on split ring
closure for lubrication and cleanliness.
These screws should not be allowed to
dry because the threads will seize.
Regularly apply Parr High Temperature
Anti-Seize Lubricant (Parr No. 424HC2)
before this happens.
10. To operate reactors equipped with an air
motor, connect air hose to a compressed
air line. For best torque and speed
control the piping to the motor should be
at least 3/8” IPS or larger. Fill the oiler
with SAE 10 oil and adjust the oiler feed
one drop per minute into the air stream.
For long continuous runs at high speeds,
the oiling rate should be increased to
three drops per minute. If the motor
becomes sluggish, flush it with a non-
flammable solvent in a well ventilated
area.
Disconnect the air line and muffler and
pour a small amount of solvent into the
inlet port. Rotate the shaft by hand in
both directions for a few minutes; then
connect the air line and run the motor until
there is not further trace of solvent in the
exhaust. If the muffler is dirty, replace it.
Relubricate the motor with a squirt of oil
into the chamber and reassemble.
11. If servicing assistance is needed, contact
Parr Instrument Company directly at the
address shown on the back of these
instructions.