SCS LABCOTER 2, Operator'S Manual

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OM-610-1002-1 Operator’s Manual Rev 37
PDS-2010 SECTION 5 OPERATION page
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5. ENABLE the Furnace / Chamber Gauge switch. Place the Vacuum switch in the HOLD position. Do not
ENABLE the Vaporizer control switch.
6. Press the PROCESS START/STOP pushbutton and turn on the chiller. After 45 minutes, place the
vacuum switch in the VACUUM position. Allow the system to pump down until the pressure reading has
stabilized for at least 15 minutes.
7. Record the pressure reading. This is the System Base pressure. The expected base pressure reading for a
properly functioning 2010 system should be less than 15 vacuum units. A base pressure above this value
generally indicates a vacuum system problem.
8. The Coating Base is normally set to System Base plus 2–3 vacuum units. Base Pressure as used in this
manual refers to the Coating Base. The Coating Base is a level that is adequate for the process and is more
easily and rapidly reached.
5.11 AUTOMATIC COATING CYCLE
5.11.1 Dimer Boat Construction
It has been shown that the best pressure control with the 2010 happens when there is maximum heat transfer
between dimer vessel and the vaporizer walls. A simple, inexpensive way to achieve this is to use a dimer boat
fabricated from standard aluminum foil, shaped to match the curvature of the vaporizer walls. The 2010 is
shipped with a 2" x 7.5" tube (called the boat form) which you can use to make disposable dimer boats from
an ordinary aluminum foil sheet. By shaping the boat so it touches as much of the heater walls as possible, the
heat transfer is optimized.
To create a dimer boat:
1. Cut a rectangular piece of aluminum foil to 11 inches by 5 inches.
2. Form the aluminum piece lengthwise along the outside diameter of the boat form. Face the shiniest side of
the foil toward the boat form.
3. Fold in the ends of the foil so it will not spill the dimer charge used in your application. Remove the dimer
boat from the form.
NOTICE: Keep your aluminum foil boat shorter than 7.5 inches. A boat longer than this will stick out
directly under the pyrolysis furnace. This could result in premature vaporization caused by heat from the
furnace section.
When loading the boat, place it only as far into the vaporizer as necessary to close the load door. This
keeps the dimer charge as far away as possible from heat generated by the pyrolysis furnace. The
maximum amount of dimer is 125g; typical amounts may be much less.
It is not necessary to use the boat form when shaping an aluminum foil boat, but it is imperative to keep the
dimer vessel no more than 7.5 inches long. The boat form is recommended because it provides the largest
possible volume for retaining powdered dimer in the vaporizer. Also, by forming a cylindrical boat that
closely matches the contour of the inside diameter of the vaporizer, the surface contact between the vaporizer
wall and the dimer boat is maximized, providing the best heat transfer path to the dimer.
Discard the aluminum foil dimer boat when the dark residue, which tends to accumulate during vaporization,
becomes moderately thick.