The Mount Holly news. [volume] (Mount Holly, Burlington Co., N.J.) 1891-1942, 1913-04-08
A KNIFE OF FLAME
Wonderful Work Done by the
0xyacetyIene Torch.
A MARVEL IN CUTTING STEEL.

This Astonishing Tool VIII Slice .
Massive Metal Beam Almost az
Quickly 40 Though It Were Made OF
Cheese-It 10 Also Used For Welding.
One of the most curious instruments
used by the structural iron workers
and steel shipbuilders, the most as
tonishing in its performance and the
most spectacular when seen at work
| is the oxyacetylene torch. 1t Is made
IN two forms-a welding torch and
cutting torch. With the former cast
iron, cast steel, steel, wrought iron.
aluminium, brass, copper, platinum
and various alloys can be welded with
ease, while perfect weld can also
be made between any combination
Of cast iron, steel, brass and copper.
Yields are often made in steel and iron
with this torch up to eight and nine
inches In thickness. the heaviest weld
of which there Is any record being
fourteen inches.
W I'LL bAC N0SbAAS tOANn HlcCl anu HUI
(other than cast from are readily cut,
with the aid of mechanical devices for
guiding the torch, up to a thickness of
eight or nine inches. This means that
with the oxyacetylene torch a piece of
steel eight Of nine inches thick and Of
any width can be cut squarely in two,
just as a carpenter saws through a
board or beam. The kerr In cutting
the steel-that is the part of the metal
that is burned away where the cut is
made-is only about one-eighth Of an
inch wide,
Steel six inches thick can be cut in
this way at the rate Of one foot In
three minutes
To the man who knows nothing of
chemistry or what actually takes place
when any object burns this seems In
credible. When the process Of combus-
ton is explained the mystery is swept
away. Combustion, then. In its sim
plest terms, consists in raising the
temperature of an object to a point
where 1t will unite chemically with the
oxygen of the air. When this chemi-
cal action takes place it is accompani-
ed by light and heat, and the object is
said to "burn.'
This temperature varies greatly with
| different objects or substances. Many
substances that burn at comparative
ly low temperature can be set on fire
with match. With these substances
every one is familiar, and other sub
stances that will not readily burn
when match is applied to them are
popularity regarded as "6reproof"
But this is wrong view. 1t may
simply mean that the temperature at
which the object will burn-called the
"kindling temperature"--is too high to
be reached by the burning match. This
is the case with iron and steel, and
when the oxyacetylene fame cuts
through a bar of steel nine inches
thick and three feet wide 1t simply
burns up layer of the metal one
eighth of an inch in thickness.
The welding torch, to describe it as
simply as possible, consists Of a handle
through which extend two tubes of
brass. These tubes are connected with
two gas tanks, one containing oxygen
and the other acetylene, and these
gases are admitted to the tubes by
valves at the rear, the oxygen entering
the upper tube and the acetylene the
lower. Both tubes open into the head
of the torch, into which is screwed a
nozzle or tip. The gases enter this tip
by separate passages and are there
mixed together and, being under pres
sure, spurted from the Jet. The acety-
lene is first turned on and lighted.
This is the fuel Of the flame. Then the
oxygen is turned on. This supports
the fame
The quantity of each gas can be reg
ulated by the valves. and thus there is
produced what is called a neutral
flame"-that is to say. it contains ned
Their an excess of oxygen nor Of acety-
lene, but just enough of each to ac-
complish complete combustion. The
temperature produced by this fame,
with an almost pencil point concentra-
ton, Is approximately 630O degrees b.
In the cutting torch there is a differ
ence In construction, because the OBJ
jeet now is not only to heat the metal,
but also to burn tito consume it by
fire. The torch Is SO made, therefore.
that at first a "preheating" fame.
which is the same as the Welding
fame, is directed against the metal, its
purpose being to heat the metal to In
candescence, or white heat" When
this point is reached a slight move
ment of the thumb on the hand hold
ing the torch opens valve that sends
flushing against the hot metal sepa-
rate stream Of oxygen under high pres
bure.
At its great heat Of $500 degrees and
In the presence of this free oxygen the
metal readily burns. The iron or steel
Is the fuel, and the stream of oxygen
supports the combustion.
The cutting torch is now used IN the
repair of ships In many ways. A new
venttlator hole, portfolio, a piece Of
damaged deck or side plating can be
cut out and removed in a few minutes.
Very often when new boilers are to be
Installed In vessel the old ones are
cut into pieces with the torch and re-
moved in few hours.-New York
Tribune.