Omaha daily bee., 1911-05-06
HIGH POWER TESTING MACHINE
valuable Equipment Installed by
the Federal Bureau of
Standards.

Some time ago an order was given by the
federal Bureau of Standards to a New
England firm for two of the greatest test
ing machines ever manufactured. One Of
these, the smaller, with a capacity Of
100000 pounds, has already been installed
in Washington and the other. with a. ca
pacity OF of 100000 pounds. is being placed
in a nearby room. The large machine,
very similar in appearance to the small
one, looks simple to the extreme when its
great strength and purpose are considered.
1t has no complicated delicate parts at a
first glance. yet IT has the power to crush to
atoms great block OF solid steel.
The purpose of the two machines is to
test iron and steel, as well all sorts of
building materials, such as reinforced con-
crete, brick piles, etc. They will afford
information for engineers and architects to
base their calculations upon. A test OF a
few seconds viii determine just how much
strain a steel girder will stand, and then
the engineer who builds a skyscraper or
bridge win be expected to tax the beam
accordingly. The strength OF a brick pier
will be a known quantity, and II will be
expected to stand the strain placed
upon It,
The two testing machines will be given
power by central hydraulic power plant
containing three accumulators. These ac-
cumuators win be placed in a room to
themselves and the power conducted by
underground passages. Zach hydraulic
pound will be weighed! in order that the
amount Of pressure needed to test piece
OF steel can be known to the exact amount
This Weighing portion of the machines is
one OF the peculiar parts. From the mas
A. 60 90 ~
other part Of the room a long copper tube
This tube has an opening about the size
of the lead in an average lead pencil.
Through the tube flows a liquid which is
weighed on the scale, and the exact amount
OF pressure needed is registered.
The larger OF the two machines IL placed
in a room about 24x6O feet. Beside 1t Is a
narrow gauge track, where a small car
carries the material to be worked upon
Overhead are huge sliding cranes that also
carry the pieces OF iron and steel to the
machine The large machine will crush a
column Of 100 square inches and thirty feet
long.
Although there are other machines likN
the two at the bureau in use in the coun-
try, none OF them comes up to the largest
as regards precision. The Phoenix Iron
company has a machine of 100000 pounds
capacity, and the American Bridge com
pany has one OF 100000 pounds capacity
but they do not have the fine Weighing
mechanism as pertains to the bureau ma
chine. They are more crude and less exact
and therefore could not be depended upon
as the new one can.
The smaller testing machine at the
bureau cost 10000. and the larger one
$4,000 Counting all the equipment and
details connected with the two machines.
3 they will cost In the neighborhood OF $4,000
to install ready for use,
The larger of the two machines, al
though made to handle huge pieces OF the
strongest steel, can test the strength OF q
tiny watch spring just as easily as it can
tell the power OF a bridge girder. The
crushing and tension parts of the machine
work on the same hydraulic plan, one pull
ing where the ether pushes.
The three aceumulators 10 be used in
furnishing power to the machines have a
combined weieht OF 100000 pounds. and are
dropped in fNty-foot Die where they rise
to the ceiling whuTi IN operation. The larE-
est Of the two testing machines weighs in
the neighborhood of 10000 pounds. AL
though both OF the devices look simple in
construction. they are not built on a simple
plan. as the blue prints prove The latter
cover masses OF sheets OF paper. and the
most experienced engineer would have no
little trouble in figuring out all the details.
To test the strength Of steel column
the latter is gripped at each END by
tapering device. The latter is screwed up
until the teeth" hold the steel firmly in
place. When the power is turned on these
teeth grip tighter than ever and steel
Is pulled from each end. When the piece
breaks, as It does when the power is
: gradually increased, the scales tell to the
. exact number OF pounds just how much
pressure was needed in the operation. In
this way 1t is known how much strain the
steel will stand.-Washingtsn Star.
Ladies', NO need 20 ask your husband
Rrnh ThA Re- nInrL-na