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12 Fbrging-Stamping - Heat Treating January, 1925
gang of nun and then dropping it from any desired
height within the limits of the machine. This contrivance
was called the Hercules and was a fairly efficient
tool for that period.
lames Watt seems to have been the originator of
the first steam hammer and it was patented by him in
1784. However, no hammers appear to have been
made under his patent and in 1839 Mr. James Nas-
FIG. 7—Kelley's first tilting converter.
myth of the Bridgewater Foundry near Manchester,
England, designed and secured a patent for the steam
hammer. This hammer was designed in response to
an appeal made to Mr. Nasmyth by Mr. Humphries of
the Great Western Company who wanted a large paddle
shaft forged for their new steamship, the Great
Britain, then under construction. After making a
complete survey of the forge shops in the British Isles,
Mr. Humphries found that none of the forgemasters
would undertake the forging of this shaft because of
the lack of proper equipment and means. However,
the style of propulsion of the steamship w-as later
changed to the screw type, the shaft was not needed
and the idea was abandoned until four years later
when the first steam hammer was built in France according
to Mr. Nasmyth's plans.
With the introduction of the steam hammer, forgings
were no longer limited to small sizes, the limiting
factor up to the time of the introduction of steel being
the difficulty in handling large piles under the hammer.
To facilitate the handling of heavier pieces,
swinging jib cranes were installed, with handworked
winches for raising or lowering the load.
The first iron steamboat in the United States was
built in Pittsburgh about 1839. The same year.a sectional
iron canal boat, the Kentucky, came over the
mountains by means of a portage to Pittsburgh and
the next year about 100 boats were made for this
service.
In 1S50 Sir Henry Chads, the captain of H. M. S.
"Excellent," reported that "whether iron vessels are
of slight or substantial construction, iron is not material
calculated for ships of war." Seventeen iron
ships which had then been in process of construction
for fighting purposes were thereupon condemned as
useless for war purposes. However, the destructive
effects of shells and other incendiary projectiles used
by the Russians against allied ships in an attack upon
Sebastopol led to the immediate use of armour notwithstanding
the previous adverse criticism of English
gunnery officers. Our first experience with armoured
war vessels was the engagement between the Monitor
and the Merrimac during the civil war which resulted
in the sinking of the Confederate Gunboat Merrimac
.>n May 11, 1862.
The discover}- of the pneumatic process of making
wrought iron (or Bessemer process as it is called) by
.Mr. William Kelley, in 1846, reads like a page from
fiction. lie and his brother bought the Suwanee Iron
Works, near Eddyville, Ky., where they had imported
about three hundred Chinese, being opposed to Negro
slavery. They were the first employers to bring in
Chinese labor in any numbers. Kelley's business was
the manufacture of wrought iron kettles for customers
in Cincinnati. His iron was refined in what was
called a "finery fire"—a slow, old-fashioned process
which used up large quantities of charcoal. One day
while watching his finery fire he noticed that the iron
was actually heated by the blast of air at the point
where there was no charcoal. The iron at this spot
was incandescent, yet there was no charcoal—notning
but the steady blast of air. The next week he publically
demonstrated the idea, converting some pig iron
into horseshoes and shoeing a horse with the metal.
There were steamboats on the Ohio River with boilers
made of iron that had been refined by Kelley's process,
years before Sir Henry Bessemer of England had made
any experiments with iron. It is no longer questioned
that the pneumatic process was an American and not
a British discovery.
Closely following the pneumatic or Bessemer
process came the Siemens-Martin or Open Hearth
process. As with the Bessemer, the open hearth
method for the manufacture of steel did not originate
with either Dr. Siemens or the Martins, having been
proposed and experimented with by various other inventors
prior to their connections with it, among
whom Josia Marshall Heath was most prominent.
But the process was not made a success until the great
,heat of the Siemens regenerative furnace was applied
to it. It is said that M. Breant of France was the
first to suggest that method of making steel.
With the introduction of steel ingots of increasing
size, many difficulties were encountered in their reduction
under the hammer. Steam hammers up to
120 tons were made, but because of the breakage of
the hammers and the tackle on the ingots due to excessive
vibration, they did not prove unqualifiedly
successful. Along with the advent of the heavier ingots
came the double acting type of hammer. This
alteration enabled a heavier blow to be struck, due to
the increased velocity of the descending hammer thru
admitting steam on the top of the piston. Moreover,
hydraulic and steam-operated jib cranes were used in
place of the hand-worked winches to handle the
heavier ingots.
The hammers which we have heretofore referred
to were used in forging between plain dies, smooth
forgings and various other pieces more or less uniform