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2. EXPERIMENTAL REACTOR ENGINEERING
Developmental work on components
for high-temperature dynamic fluid
systems has continued, with the effort
being primarily on pumps, seals, heat
exchangers, and instrumen tation.
Centrifugal pumps with both gas seals
and frozen seals have operated suc-
cessfully over the temperature range
of 1200 to above 1500°F, and operational
difficulties with these pumps have
become less frequent. Techniques have
been developed for remotely stopping
and restarting pumps incorporating a
frozen-fluoride seal.
Emphasis has also been placed on
seal research in an effort to find
better materials for packing rotating-
shaft seals and valve-stem seals.
In the search for materials that w i l l
have negligible change in physical
properties at high temperatures and
w i l l furnish some lubrication to the
shaft at these temperatures, several
promising materials were found. A
program is under way to develop a
face seal that will seal high-temper-
ature fluids against a gaseous atmos-
phere, with the minimum leakage.
Various rotating-shaft seals for
con tai n i n g hi gh - tempe ra tur e 1 i quid s
have been tested. To date, the best
results have been obtained with a
packed seal in which the pumped liquid
may be frozen. A program is under way
for developing a special type of seal
in which a material different from
the liquid being pumped and having a
higher melting temperature is injected
into the seal and frozen. Tests
conducted to date indicate that this
type of seal shows promise.
Heat transfer tests have been
conducted with the sodium-to-air
radiator, and the sodium inlet temper-
ature has been increased to 1700'F.
The radiator tested had 15 fins per
inch, which were sectioned every
2 inches. This gave a net improvement
of 20% in the over-all heat transfer
H. W. Savage, ANP Division
PERIOD ENDING DECEMBER 10, 1952
coefiicient, as compared with that for
an unsectioned radiator. A bi-fluid
heat transfer system has been con-
s tructed, and shake-down tests have
been conducted satisfactorily.
The rotameter type of flowmeter
that uses a tapered core riding inside
an induction coil as the float-position
sensing element has given very satis-
factory performance. This type of
flowmeter w i l l be used in the ARE.
The Moore Nullmatic pressure trans-
mitters, modified for high-temperature
opera ti on, have gi ven trouble - f ree
per forman ce du ring several hundred
hours of operation with pressure
transmi tter temperatures as high as
1400°F. Pressures up to 70 psi were
measured.
Techniques for the vacuum distil-
lation of small quantities of NaK
from liquid systems are being developed,
since all the NaK used for cleaning
the ARE fuel system cannot otherwise
be removed. Tests have continued for
determining the tempera tu r e-depend enc e
of gas line plugs above systems
employing a ZrF, -bearing fluoride
mixture. Vapor condensation traps for
this ZrF, vapor, in which the vapor
is bubbled through the eutectic
NaF-KF-LiF, have been sa tis factori ly
tested.
Improvements made in the plant
facilities are the installation of a
helium distribution system, the
expansion of the fabrication shop
facilities, the completion of the
instrument shop facilities, and the
installation of six gas-fired furnaces.
PUMPS FOR HIGH-TEMPERATURE FLUIDS
W. €3. McDonald G. D. Whitman
W. G. Cobb W. R. Huntley
A. G. Grindell J. M. Trummel
ANP Division
Pump with Combination Packed and
Frozen Seal. In the first test,
the pump with the combination packed
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