Daily capital journal. (Salem, Oregon) 1903-1919, 1913-03-25
A knife OF FLAME
Wonderful Work Done by the
0xyaCetyIene Torch.
A MARVEL IN CUTTING STEEL.

| Cheese-lt Is Also Used For Welding.
One Of the most curious instruments
used by the structural iron workers
aud steel shipbuilders, the most as.
tonishlng in its performance and the
most spectacular when seen at work
is the oXyHcetylene torch. 1t is made
in two forms-a welding torch and a
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
With the cutting torch steel and iron
(other than cast IRON are readily cut
with the aid OF mechanical devices for
guiding the torch, up to 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 kerf 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.
tion 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 it will unite chemically with the
oxygen of the air. When this chemi-
cal action takes place 1t 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 a 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-caled the
"kindlng temperature"-i too high to
be reached by the burning match. This
is the case with iron and steel, and
when the oXyacetylene fame cuts
through bar of steel nine inches
thick and three feet wide 1t simply
burns up a layer Of the metal one
eighth Of an inch in thickness.
The welding torch. to describe it as
simply as possible, consists Of handle
through which extend two tubes Of
brass, These tubes are connected with
two gas tanks, one containing oxygen
and the other acetyene, and these
gases are admitted TO the tubes by
valves at the rear, the oxygen entering
the upper tube and the acetyene 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-
lcne is first turned on and lighted
This is the fuel Of the flame. Then the
oxygen Is turned on. This supports
the flame.
The quantity Of each gas can be reg.
ulated by the valves, and thus there is
produced what is called a neutral
tlnme'-that is to say, 1t contains nei.
ther an excess Of oxygen nor of acety-
lene, but just enough Of each to ac.
compllsh complete combustion The
temperature produced by this flame,
with an almost pencil point concentra.
ton, is approximately G,300 degrees f.
In the cutting torch there is a differ.
ence In construction, because The oh.
ject now Is not only to heat the metal,
but also to burn ito consume II by
fire, The torch is 80 made, therefore
that at first "preheating" dame
which Is the same as the welding
flame, Is directed against the metal, lis
purpose being to heat the metal to In
candescence, or white heat" When
this point is reached slight move.
ment Of the thumb on the hand hold
ing the torch opens valve that sends
rushing against the hot metal sepa-
rate stream Of oxygen under high pres.
sure
At its great heat of $500 degrees and
in the presence Of this free oxygen tho
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
ventiator hole, portfolio, piece Of
damaged deck or side plating can be
cut out and removed in few minutes
Very often when new boilers are to br
installed in vessel the old ones arc
cut into pieces with the torch and re-
moved in few hours. New YorB
Tribune.