Performing An Analysis - Micromeritics 1305 Operator's Manual

Performing an Analysis

Performing an Analysis
The following step-by-step procedure assumes that the >5/<5 valve and the
>35/<35 valve have been set to the desired range, that the matching insert is in
place or available, and that the matching sample cup contains the sample to be
analyzed. Appendix B contains a sample data sheet for organizing and recording
data.
1. Ensure that the FILL valve is in the CLOSE position.
2. Place the PREP/TEST valve in the PREP position.
3. Ensure that the VENT valve is in the OPEN position.
4. Remove the sample chamber cap.
5. Remove any previous sample and/or insert and cup.
6. Place the new sample and/or insert into the chamber.
7. Replace the sample chamber cap; securely tighten.
8. Close the VENT RATE and FLOW RATE valves.
9. Place the FILL valve in the OPEN position.
10. Open the VENT RATE and FLOW RATE valves to approximately mid-range.
If your sample is a light powder, open the valve slowly to avoid splashing
of the powder.
11. Air and vapors trapped within pores, crevices, or among the pieces of the
sample will be removed from the sample by a prolonged purge in this condi-
tion. However, these gases are much more rapidly removed by alternately in-
creasing and decreasing the gas pressure in the sample chamber. Place the
VENT valve in the CLOSE position and allow the pressure to rise.
12. When the indicated pressure has risen to, say, 16 to 18 psi, close the FILL
valve and open the VENT valve. When the indicated pressure then drops to,
say, 1 to 0.5 psi, close the VENT valve and open the FILL valve. Repeating
this procedure 8 or 10 times adequately purges from most powdered or po-
rous samples whatever gases they originally entrained and replaces them
with the "working" gas, i.e., the helium or dry nitrogen.
13. Place the FILL valve in the CLOSE position and the VENT valve in the
OPEN position.
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Model 1305 MultiVolume Pycnometer
Jun 99