Chandler Engineering AMETEK 7200, Инструкция по эксплуатации

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2-22 SECTION 2 – OPERATING INSTRUCTIONS
System Shutdown and Post-Test Cleanup
The Model 7200 CHA has a recommended shutdown procedure to ensure all sub-
components are properly turned off and all necessary parameters are stored in the system
files. If the system is shut down other than by the recommended procedure, some parameters
may not be saved.
1.
Turn off the Automatic or Manual data logging, if still running.
2. Turn off the oven heating by entering an Oven Temperature Set point of 0.0°C. You can
also turn off the HEATER switch on the oven.
3. Lower the Gas Injection Pressure and H
2
O Confining Pressure to atmospheric by turning
their regulator knobs fully CCW (counterclockwise), and open the H
2
O PURGE valve to
release all pressure from the CHA Vessel and Stand.
4. After the oven is cooled enough to allow safely working with the CHA Vessel, open the
oven door and carefully disconnect all the tubing from the vessel (in case any pressure is
still trapped).
5. Remove CHA Vessel from the stand:
a. Check again that all pressure has been released from all parts of the vessel.
b. Rotate hand knob (Item 24 on #7200-1010 CHA Vessel w/Stand assembly
drawing) CCW (counterclockwise) to raise upper arm (Item 18).
c. Pull plunger knob (Item 19) out and rotate 90° to hold it out.
d. Rotate upper arm 90°, out of the way of the vessel.
e. Loosen tube fitting nut on Cement Temperature RTD, and remove RTD from
vessel. The TFE tubing (Item 12) should allow the RTD to pull easily out of the
cement without sticking.
f. Raise vessel slightly from lower arm (Item 17), and tilt it and lift it to remove it
from stand.
6. Disassemble the CHA vessel as necessary. Pull the upper end plug (with RTD, if still
connected, and metal wafer/baffle) off the top of the sample tube (Item 1).
7. Pull the bottom end cap, retainer, and diaphragm/stem assembly to remove it from the
bottom of the sample tube.
8. Dispose of the sample tube with cement set up in it.
9. Clean cement from all other parts, and re-use as possible. Be careful to not scratch
sealing surfaces.
10. Make sure cement has not plugged the porous metal element (Item 14) inside the stem. If
it has, blow it clean or replace it.
11. Inspect, and flow water through tubes, as necessary, to make sure that tubes and filters
are not plugged with cement. Replace (or clean cement from) the tubes, filter elements, or
filters, as necessary. To check and purge the Pore Pressure tubing and related flow path,
you can connect part #7200-
1109 “ TUBE, PURGE, CHA, SHORT” (or make your own
with two 1/8” Swagelok unions and a piece of 1/8” -OD tubing) between the unconnected
H
2
O Fill/Purge tubing (“Fill Cell Top”) and the Pore Pressure tubing inside the oven
(with the filters still connected to these tubes exiting from the oven wall). Then, open the
3-way valve on the front panel to the FILL CELL TOP position, open the H
2
O PURGE
VALVE, and allow the water pressure to flow water through the tubing. If you do not see
water flowing freely out through the H
2
O PURGE tubing (length of 1/8” -OD translucent
PFA tubing connected to the H
2
O PURGE connection on the back of the CHA cabinet,
with the open end routed to a beaker), then you must clean cement from the tubes and/or
filter, or replace those parts.