Dynasonics MFX Series Insertion MagProbe Flow Meter - Manual (Page 34)

Rev. 01/11 -2.9- MFX
4. Slowly open the isolation valve. When the valve is fully open,
use a 9/16" wrench on the insertion nuts, alternately tightening
each nut about two complete turns to avoid uneven seal
loading—two 9/16" ratcheting wrenches can expedite this
process. Repeat until the length of probe remaining above the
seal fitting equals the “D” length calculated in step D.
NOTE: For some low pressure/low temperature [less than 30 psi (2
Bar) and less than 100 °F (38 °C)], the MagProbe may be pushed in
by hand to decrease the insertion time. Dynasonics also offers
insertion cranking tools for these probes.
PROBE RETRACTION PROCEDURE
1. Retract the MagProbe by loosening the Upper Jam Nuts
counterclockwise—as viewed from the top of the MagProbe—
using a 9/16" wrench. If the pipe is under pressure, the nuts
must be turned alternately about two turns at a time to prevent
binding as a result of non-equal seal loading—two 9/16"
ratcheting wrenches can expedite this process. In many cases,
the line pressure will cause the MagProbe to retract. Should the
MagProbe bind or if system pressure is very low, use the
retraction nuts on the lower side of the MagProbe flange to
assist in the MagProbe retraction. Continue this procedure until
the MagProbe is fully retracted into the insertion fitting.
CAUTION: Do not run the drive nuts off the rods until the isolation
valve is fully closed.
2. After the MagProbe is retracted past the “ball” in the isolation
valve, the Isolation Valve may be closed to isolate the MagProbe
from the line and the MagProbe can be removed entirely.
CAUTION: If the probe tip is not above the “ball” of the isolation
valve, the valve cannot be closed. If the valve will not close
smoothly, the body or tip of the MagProbe is most likely not above
the “ball”. Attempting to force the valve into the closed position may
result in damage to the probe.
PART 2 - MAGPROBE INSTALLATION
Retracting DMP2
through DMP6
Probes