Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1917-01-23
ARMOR PLATE PLANT
DESCRIBED IN DETAIL
IN FEDERAL BULLETIN
Civil Engineer of Navy Pre-
pareS Some Interesting
Facts and Figures for Amor
Plant Board

WASHINGTON. Jan 2o.-The bulle-
tin issued by the armOr plate board
contains lots Of interesting and Hum
mating information about the s11.OOo.-
600 plate plant that is TO be erected and
operated by the federal government II
was prepared by r f Bakenhus. civII
engineer. L. s. y. member and recorder
OF the special board
The points covered may be summar-
! -tzed thus.
l. What constitutes an armor plant
such as is contemplated by the gov
eminent
g The requirements for its efficient
and economic operation
3 The conditions which will largely
influence the selection OF A site
Beginning at the beginning. the bull
letin declares that the manufacture OF
armor plate is highly specialized
branch OF the steel industry Its manu-
facture requires a different process from
that used in the manufacture OF com
mercial steel.
The plate is used in gun Uurrets. con-
ming towers and uptakes. but its chief
usefulness is found in the narrow belt
below and just above the water line of
the ship. The largest plates are % feet
thickness of IS inches They weigh APP
proximateIy fOrty-fve tons The ingot
from which such a plate IS made would
weigh $4,000 pounds.
PROCESS OF MANUFACTURE
How do YOU suppose such n colossal
piece OF buIlet-proOf steel is manufac-
tured. The bulletin describes the pro-
cess. beginning it's description with the
statement that the government contem-
plates the manufacture Of armOr from
Bessemsr pig iron purchased in the
opep market
The pig iron thus acquired will be
melted in open hearth furnaces. reduc-
ing the amount OF carbon and eliminat-
ing impurities in the pig iron such as
L are found in the product Of the COM
mercfal furnaces The correct amounts
Aof nickel and chromium are added to
his product at the proper time. produc-
ng an alloy steel Of the proper cOmpO-
sttion for armor plate The metals are
hen poured into an ingOt preparatory
for making the plate
The necessity of using a large amount
pf scrap from the ilgOts complexities the
problem OF manufacture. After being
rought TO the proper temperature, the
ngot is placed under the hydraulic
presses These exert A pressure of TO-
1000 10 1900 tons upon a area OF a few
Atnches wide and several feet long thus
reducing the thickness and increasing
the area OF the inEot to the proper
dimensions Of the plate
The plate must be hardened. To &C
fOmplish this, two armOr plates Of the
rerEHe size are placed face to face with
a layer OF carbonaSeous material be-
tween them They are confined by A
border Of fire brick. and are subjected
10 stemperature Of 1000 degrees +. for
a period OF from fourteen to sixteen
days This operation is known as
cementatiOn. and causes carbon from
the charcoal TO penetrate about one inch
into the metal. which. upon being
chilled, forms a surface so hard that it
will scratch glass.
Lots OF heavy machine work is re-
CURED BY the plates 10 provide means
for fastening and holding them on the
ships and for making them At into
: proper places on the armor belt In
some cases as much as 20 per cent of
the plate must be cut away in this
work
ARMOR PLANT DESCRIBED.
The plant authorized BY congress.
that is TO be erected al Rome or else
where, must have capacity OF not less
than 10000 tons OF armOr per year. Its
cost. as widely advertised will be ap-
NoAiAistte49 fAA.vvv-vVv- Ine establish
ment Will consist OF an electric power
plant. boiler shop. an open hearth fur
mace room. forging and bending plant,
cementing and tempering shop. a ma
chine shop There will be also an office
building, laboratory building and such
miscellaneous structures as may be re-
CURED for auxiliary purposes.
The open hearth furnaces. FIVE in
number. wil be housed in a building
about 200 feet long. The forging and
bending shop Will contain four furnaces
for heating ingOts. and ten furnaces for
plate heating. besides the heavy forging
presses, with inJensifier and pumps. The
building viii be about l.2OO feet long.
Thirty-five furnaces will be located in
the tsmpering and cementing shop. and