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Matthias, F. T. (ed.) / The Wisconsin engineer
Volume 33, Number VI (March 1929)

Morrison, L. W.
Engineering review,   pp. 212-III


Page 212


The WISCONSIN ENGINEER
               "I ~ ~ ~ ~ ~ ~ ~ ~ -
    SS Mater~
               ll  ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ (l
a_ I
PURE MANGANESE PRODUCED
         BY DISTILLATION
  IPure manganese has recently been
produced in the Bureau of Metallurgi-
cal Research of the Carnegie Institute
of Technology. Samples of the metal,
which never before has been produced
in quantity in such a purified state,
and of the furnace in which it was
made, were exhibited at the open
meetin' r of the Metallurgical Advisory
Board held in Pittsburgh recently.
  Pure manganese has a bright silvery
luster, and unlike many of the pure
metals, which are soft and ductile, it
is extremely brittle and hard enough
to scratch glass. The pure metal was
distilled from crude metallic man-
ganese placed in a pure magnesia
crucible over which a similar crucible
was inverted to condense the man-
ganese vapor. The whole was placed
in a closed silica tube connected with
a vacuum pump, and heated with a
high frequency induction furnace us'
ing an alternating current of several
amperes at a frequency of 20 kilo-
cycles.
                -Scientific American
   SHOOTING DOWEL PINS IN
          STEEL PLATES
  Much interest was exhibited by pro-
duction men of the Society of Auto-
motive Engineers at Detroit recently
in an account of high velocity pene-
tration devices.
  The device demonstrated, resembled
a pneumatic hammer with an over-
size barrel. It is really a gun (which
drives a 1/2 in. conical shaped pin
into steel plates 12 to 1 X4 in. thick)
equipped with recoil and silencing
devices.
  A cartridge containing about a half
of a teaspoonful of commercial powder
is used for shooting a 1 2 in. pin into
a 34 in. plate.
  Since the device will pin together
adjoining pieces of steel without the
necessity of previously punching or
drilling holes, it is being developed for
erecting members prior to welding
joints in buildings, bridges, or tanks.
It will also be valuable in applying
patches to ship hulls or in sub-
aqueous piping. It has also been suc-
cessfully applied for fastening parts
to automobile chassis.
  The pins are made of chromium-
molybdenum steel; and are so shaped
that they penetrate the plate without
punching a slug therefrom. The action
is described as one wherein the first
small hole is expanded so rapidly that
the inertia effects cause the hole to be
momentarily larger than the pin tail.
Elastic forces soon counteract the in-
ertia effects and the hole contracts so
rapidly that the flying pin is caught
before it gets entirely through, and is
held so tightly that about 20,000 lbs.
pressure is required to force the pin
out of a 34 in. hole.
  I his principle has po!
the field of forging betwe(
in the near future shou
effect on the present met]
type of work.
  BUREAU OF STANDA
     STUDY CHEMISTR
       PORTLAND CEM]
  An experimental cemen
a capacity of 10 lbs. per c
built at the Bureau of c
Washington. The purpo
beyond the laboratory worn
amounts of pure materials
with commercial raw ma
manner more representativ
mill practice.
  This is expected to ha
bearing on cement manul
lowing the discoveries al
at the Bureau as to the bas
of Portland cement.
         -Engineering J'
ELECTRIC MACHINER1
       BY HYDROGEN
  As much as 5 0 % more
be handled by the same si
apparatus if it is equipl
hydrogen cooling system d
the engineers of the Gen(
Company, it was announc
in a report made public re
use of hydrogen gas with
enclosed rotating machine has made
this increase possible without increas-
ing the operating temperature beyond
the point of safety. This temperature
has heretofore been the limiting factor
in the load which can be carried.
  The first commercial application of
the new system of hydrogen cooling
has been made on a synchronous con-
denser installed by the New England
Power Company at its Pawtucket,
Rhode Island substation, which has a
capacity of 12,000 kilo-volt amperes
as compared with only 10,000 kilo-
volt amperes if an air-cooling system
were not used. With hydrogen as
the cooling agent at 15 lbs. gage pres-
sure, the machine will deliver 15,000
kilo-volt amperes without exceeding
ssitilities in  the normal temperature range as speci-
mn dies, and  fied in the guarantees.
Id have an       Another advantage of the new sys-
aods in this  tem, it is said, is to exclude oxygen
              and dirt. Hydrogen will not support
-Iron Age     combustion, and fires of any kind, even
              from short-circuits, are consequently
LRDS TO       impossible. Hydrogen is also useful
Y OF          in the diminution of the corona effect
ENT           on the insulation, the report says. The
t kiln, with  usual air cooled  machine must be
lay, is being  placed within the building, while the
Standards at  hydrogen-cooled  equipment can    be
mse is to go  placed outdoors, thus saving building
e with small  costs and cutting down noise.
and to work
terials in a     NORFOLK TO HAVE DIESEL-
of modern         ELECTRIC FERRY BOAT
                 A double-end steel diesel-electric
ve a direct   ferry boat is now under construction,
:acture, fol-  for service between Norfolk and Ports-
ready made    mouth, Va.
ic chemistry     It will have an overall length of
              173 feet and an overall beam of 57
Sews-Record   feet.
                 The power plant consists of two
  COOLED      diesel engines, each rated at 400 brake
GAS           H. P. at 250 r. p. m. directly connected
power can    to two main generators delivering 250
,ze electrical  volts D. C. and 270 KW., and two
)ed with a    exciters rated at 30 KW. and deliver-
eveloped by   ing 125 volts at 250 r. p. m.
.ral Electric   The main    generators are of the
-ed recently  shunt wound and the exciters of the
cently. The   compound type.
in a totally             -Engineering Contracting
212
Volume 3 3, No. 6


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