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Assembly:
To assemble, use a little lubricant on the stem of the burette (5003-25)
and the level bottle (5047) and immerse the connection tubing
(5052) and the rubber coupling (5046) in hot water
to facilitate insertion of the tubing. Now connect the rubber coupling
(5046) to the center stem of the burette and connect the
other end of the coupling to the hose nipple (5057) of the
Whitey valve (5055). Connect the connection tubing (5052)
to the side stem of the level bottle (5047). Assemble the
burette clamp (5006) around the burette and fasten in place
on the support rod(5016).
Operation:
Warning:
Caustic Solution is used in the operation of this instrument. This
solution may cause severe burns to the operator if not handled with
care. Wear goggles and protective clothing while operating this
instrument.
The instrument
is now ready for operation but should first be tested for any gas
leaks that may occur at various connections. This may be accomplished
by pressurizing the instrument and applying a soapy solution to
the various connections and joints. The instrument may also be submerged
in a glass tank of water, and leaks observed in this manner.
The generally
accepted temperature for gas analysis is 77ºF/25ºC. Therefore, it
is good practice to bring samples to this temperature prior to testing.
The volumes of CO2 gas may be determined by taking the maximum pressure
reading during the test and then, immediately after the test, inserting
a laboratory thermometer into the sample and recording the temperature.
The CO2 content can be determined from any standard temperature/pressure
relationship chart using the above information.
- Close the
Whitey valve (5056), open the burette cock (5005)
and put approximately 100cc's of water in the level bottle
(5047), elevating the same above the burette so as to allow
the water to run down into the burette to the bottom of the calibrations.
- Close the
burette cock and lower the level bottle to its stand (5050)
- Place a small
beaker of water under the rubber seal (5045) and lower
the cross bar (5024) so as to submerge the rubber seal
in the water. Note: The cross bar is lowered by depressing the
lock pates (5026) on each side of the cross bar and pushing
downwards. When the lock plates are released, the cross bar will
remain firmly locked in position.
- Open the
Whitey valve (full). This will cause the water top be drawn upward
through the Whitey valve, displacing any trapped air in the system.
Tap the tubing to release air into the burette
- Close the
Whitey valve and remove the beaker from the piercing needle (5042A)
- Open the
burette cock and allow the water to return to the level bottle.
Discard the water.
- Replace the
water in the level bottle with caustic solution, filling it approximately
half full. Note: Wear protective clothing and goggles when using
caustic solution. A 20% solution of either Potassium Hydroxide
or Sodium Hydroxide is recommended for air testing. (* A weaker
solution may be used, but the tests will take longer and fewer
tests can be performed.) To make a 20% solution, slowly add 100
grams of Potassium or Sodium Hydroxide crystals to 500 cc's of
distilled water and store in a sealed jar. The above solutions
may also be purchased from any laboratory/chemical supply company
- Raise the
level bottle to fill the burette completely and close the burette
cock. To prevent overflow, the caustic trap (5079) is furnished
for attachment at the top of the burette. While filling the burette,
check the plastic connection tubing (5052) and work out
any air bubbles that may be present
- Place the
bottle or can to be tested on the base pad (5022) and lower
the cross bar to the point where the rubber seal just touches
the top of the container.
- Depress the
lock plates and push the cross bar rapidly downwards until the
container is pierced.
- Release the
lock plates. The cross bar will remain locked in place with the
rubber seal compressed to prevent leakage at the point of piercing.
Be careful not to trip the lock plates after piercing as only
a slight upward pressure on the lock plates will release the cross
bar.
- Hold the
instrument at the bottom of the base with the right hand while
the left hand holds both the guide rod (5017) and support
rod (5016). Shake the instrument with a rapid back and
forth motion until maximum gauge pressure has been obtained. Note:
The burette is very fragile and may break if it comes in contact
with an object while shaking the instrument. Also, be sure that
the level bottle and stand are located in such a manner that they
do not tip over while shaking the instrument.
- Open the
Whitey valve (5056) and allow gas to flow into the burette,
reducing the gauge pressure to 5 psi or less. Shake the instrument
a few times to allow absorption of CO2 gas by the caustic solution.
It is also advisable to invert the instrument and allow the gas
that was released into the burette to be absorbed in the larger
bottom bulb of the burette. The shaking of the instrument allows
for more build up of gas in the test container and for the next
release of gas into the burette.
- Open the
Whitey valve and repeat the above process again. Usually eight
or ten shakes are enough to remove most of the air in the sample.
For very accurate work, however, the operation should be continued
until a constant air reading is obtained. When making the air
reading in the burette, the level bottle should be raised so as
to bring the liquid in the burette and level bottle to the same
level.
Air Readings: If air readings tend to increase after a period
of testing, the caustic solution may be diluting and should be
replaced with a fresh solution. The number of tests that can be
expected from the caustic solution may vary according to the strength
of the solution being used.
- Close the
Whitey valve and release the lock plates by pressing them in an
upward direction and then raise the cross bar to a level that
will allow the removal of the container.
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