Parr Instrument 1104 - Manual (Page 7)

1104 Oxygen Combustion Vessel
w w w . p a r r i n s t . c o m 7
threaded on instead of pushed on to the inlet valve.
The correct assembly to use when filling the 1104
from a calorimeter is P/N A19A15. Close the outlet
valve on the bomb head. Thread the end of the fill
connection on to the inlet valve of the 1104. Press
“O2 Fill” on the calorimeter to fill the vessel.
Filling the Bomb Manually
To fill the vessel directly the 1823 Oxygen Fill Con-
nection must be used. Close the outlet valve on the
bomb head. Open the oxygen tank valve not more
than a quarter turn. Open the control valve on the
fill connection slowly and watch the bomb pres-
sure rise to the desired filling pressure. Close the
control valve on the fill connection. The inlet check
valve will close automatically when the residual
pressure in the filling hose is released; leaving the
bomb filled to the highest pressure indicated on
the gage. Release the residual pressure in the fill-
ing hose by pushing downward on the toggle relief
lever attached to the fill connection. The gage should
now drop to zero. If the pressure drops slowly and
a large amount of gas escapes when the pressure
relief valve is opened, the check valve in the bomb
head is not operating properly. This trouble will have
to be corrected before the bomb can be used.
If too much oxygen should accidentally be intro-
duced into the bomb, do not proceed with the
combustion. Detach the filling connection, exhaust
the bomb, remove the head and reweigh the sample
before repeating the filling operation.
When using the bomb in a calorimeter, insert the
lifting handle into the two holes in the side of the
screw cap and lower the bomb partially into the
calorimeter water bucket. Note that the bucket
should be filled with 1850 mL of water. Press the
banana plugs on the two ignition wires firmly into
the terminal sockets on the bomb head before the
head is immersed in the water. After connecting the
wires lower the bomb into the bucket. Remove the
lifting handle and shake off any drops of water back
into the bucket. The calorimeter should be standard-
ized using an amount of Benzoic Acid that releases
approximately the same amount of energy as the
sample to be tested. An approximate EE value for
the 1104 in the 6000 Series instruments is 2500
cal/°C.
When using the bomb alone, it must be connected
to an ignition unit (P/N 2901). Always place the 1104
Oxygen Combustion Vessel behind a heavy shield
or barricade and completely submerge the bomb in
cold running water while firing. If the sample devel-
ops an unusually large amount of heat, it is recom-
mended that a cold stream of water be run against
the bomb to facilitate cooling.
Note: Do not fire the bomb at any point if there
is gas leakage.
The bomb must remain in the water bath until all
parts of the head and screw cap come to tempera-
ture equilibrium. Then remove the bomb from the
bath, wipe it with a clean towel and release the
residual gases through the needle valve before
unscrewing the compression screws and removing
the cap. If necessary, a spanner wrench (P/N 219A) is
provided to remove the screw cap of the vessel.
Maintenance
The chromium plated, steel alloy screw cap on the
bomb requires special care to keep the threads
from rusting and to prevent seizure. Always dry the
cap thoroughly after it has been used and store the
bomb with the screw cap removed from the cylin-
der. Keep a light coating of anti-seize lubricant (P/N
424HC2) on the threads of the cap but do not use
this or any lubricant on any other parts of the bomb.
Basic maintenance of the bomb including replacing
the O-ring, insulators, gaskets and spacers is recom-
mended every 500 firings. If the bomb is used for
samples that contain a high amount of corrosive
materials, this maintenance should be completed
after every 250 firings.
Parr provides Oxygen Bomb repair services for the
1104 (P/N REPAIR.O7). A factory test is recommend-
ed after 5000 firings. This includes replacing all of
the seals, checking the dimensions of the cylinder,
screw cap and head, hydrostatically testing the seals
and proof firing the vessel using benzoic acid.
When returning a bomb to the factory, ship it to:
Parr Instrument Company
Attn: Repair Department
211 53rd Street
Moline, IL 61265-1720
Include a Purchase Order to cover the cost of the
repair, a person to contact (complete with a phone
number) and return shipping information. Individual
repair parts can be ordered from any Parr dealer or
directly from Parr.