The members of the American Gun Foundry Board visited these works in
1883, and give the following in their report: The most important steel
works in France are situated at Le Creusot, and bear the name of the
location in which they are situated. These works have advanced year by
year in importance and in magnitude since their purchase by Mr. Eugene
Schneider.
This gentleman's death, in 1875, was a source of mourning to the
whole town, the inhabitants of which looked up to him as a father. The
grateful people have erected to his memory a monument in the market
square.
Under the administration of his son, Mr. Henry Schneider, the fame of
the products of the works has been enhanced, and the proportions
of the establishment have been much increased. The whole number of
workmen now employed here and at other points amounts to 15,000; and
it is the great center of industry of the adjoining region. At no
other place in the world is steel handled in such masses.
It would be foreign to the purpose of this report to dwell on the many
objects of commerce which are supplied from these works, but it is
safe to say that no proposed work can be of such magnitude as to
exceed the resources of the establishment.
For the preparation of metal for cannon and armor-plates Le Creusot
is thoroughly equipped. The iron is produced on the premises from the
purest imported ores, and the manufacture of the steel is carried on
by the most approved application of the open-hearth system with the
Siemens furnace; the chemical and mechanical tests are such as to
satisfy the most exacting demands of careful government officials; and
the executive ability apparent in all the departments and the evident
condition of discipline that pervades the whole establishment inspire
confidence in the productions of the labor.
The capacity for casting steel is represented by seven open-hearth
furnaces of 18 tons each, equal to 126 tons; and the process of
casting large ingots is a model of order and security. Ladles capable
of holding the contents of one furnace, mounted upon platform cars,
are successively filled at a previously determined interval of time
and run on railways to a convenient position over the mould; before
the first ladle is exhausted the supply from the succeeding one has
commenced to run, and so on to the completion of the casting, the
supply to the mould being uninterrupted during the entire process. The
precision with which the several ladles are brought into position in
succession makes it entirely unnecessary to provide a common reservoir
into which all the furnaces may discharge. By this process the casting
of a 45 ton ingot, which was witnessed by the Board, was effected in
23 minutes.
The process of tempering the gun-tubes was also witnessed by the
Board. The excavation of the pit is, as at St. Chamond, 15 meters
deep, with the furnace at one end and the oil tank (100 tons) at the
other. One side of the upright furnace is constructed in the form of a
door, which, by a convenient arrangement for swinging, is made to turn
on its hinges. Thus, when the tube is raised to the right temperature,
it is seized by the traveling crane, the door of the furnace swung
open, and the tube at once advanced to the tank in which it is
immersed.
All tubes are immersed in oil the second time, but at a temperature
much below that to which they are raised at the first immersion. This
process constitutes the annealing after tempering.
The manufacture of steel-armor plates is a specialty of Le Creusot,
which is engaged in an active competition with the manufacturers of
compound armor. Plates up to 60 centimeters in thickness and 3 meters
wide are forged here; they are tempered after forging, but what
subsequent treatment they receive was not explained.
The tempering pit for the plates consists of an excavation of
convenient size, in the center of which is placed a tank containing
180 tons of oil. At the four corners of the pit are furnaces in which
the plates are raised to a proper temperature. When sufficiently
heated, a plate is seized by a walking crane and immersed in the oil.
Hoops for cannon are manufactured here in large quantities. They are
cut from solid ingots, and those for guns up to 24 centimeters are
rolled like railway tires; those for larger calibers are forged on a
mandrel. Jackets of large size are also manufactured; these are made
from solid ingots, which, after being forged, are bored out.
At Le Creusot a remarkable test of hoops was witnessed, which
exemplifies not only the excellence of the manufacture of the steel
but also the exacting character of the French requirements. The hoops
for naval guns are made with the interior surface slightly conical.
When forged, turned, and brought under a hammer, a standard mandrel of
steel, conically shaped to suit the form of the cone in the hoop, but
of a slightly increased diameter, is introduced, the smaller end
of the mandrel being able to enter the larger end of the hoop. The
mandrel is then forced in by the hammer until its lower edge has
passed through the hoop. The blows are then made to operate on the
upper edge, detaching it from the mandrel. Careful measurements are
taken of the diameter of the hoop before and after this test, and it
is required that the measurement subsequent to the operation shall
show that the hoop has partially, but not entirely, returned to the
diameter that it had before the entrance of the mandrel. This would
show that there is left to the metal a small margin within its elastic
limit. A system of manufacture which can comply with such a refinement
of exactitude must be very precise.
Perhaps the most striking feature at Le Creusot is the forge, where is
assembled an array of steam hammers not equaled in the world, viz.:
One 100 ton hammer with a fall of 5 meters.
One 40 ton hammer with a fall of 3 meters.
One 15 ton hammer with a fall of 3 meters.
Two 10 ton hammers with a fall of 2½ meters.
One 8 ton hammer with a fall of 2½ meters.
As the 100 ton hammer at these works is the largest in the world, some
particulars concerning it will be appropriate.
The foundations are composed of a mass of masonry laid in cement
resting on bed rock, which occurs at a depth of 11 meters, an anvil
block of cast iron, and a filling-in of oak timber designed to
diminish by its elasticity the vibrations resulting from the blows of
the hammer. The masonry foundation presents a cube of 600 meters.
Its upper surface is covered with a layer of oak about one meter in
thickness, placed horizontally, on which rests the anvil block.
At the Perm foundry in Russia the anvil block for the 50 ton hammer
is made in one piece, moulded and cast on the spot it was intended to
occupy. Its weight is 622 tons. At Le Creusot, however, this idea
was not approved, and it was determined to construct the block in six
horizontal courses, each bedded upon plane surfaces. Each course is
formed of two castings, except the upper one, a single block, which
weighs 120 tons and supports the anvil. Thus formed in 11 pieces, it
is 5.6 meters high, 33 square meters at the base, and 7 square meters
at the top. Its entire weight is 720 tons.
The space between the block and the sides of the masonry in which it
rests is filled in solidly with oak. The block is thus independent of
the frame of the superstructure.
The legs of the frame, inclining toward each other in the form of an
A, are secured at their bases to a foundation plate embedded in the
masonry. They are hollow, of cast iron, and of rectangular cross
section, each leg in two pieces joined midway of their length by
flanges and bolts. The legs are also bound together by four plates of
wrought iron, which, at the same time, holds the guides. The height of
the legs is 10.25 meters, and their weight, with the guides, 250 tons.
The binding plates weigh together about 25 tons, and the foundation
plates 90 tons.
The entablature of the frame work weighs 30 tons; on it is placed the
steam cylinder, single acting, made in two pieces, each 3 meters
long united by flanges and bolts. The diameter of the cylinder is 1.9
meters, giving a surface of 27,345 square centimeters (deducting the
section of the rod, which is 36 centimeters in diameter); which, for
5 atmospheres, gives a pressure under the piston of about 140 tons.
As the weight of the hammer is 100 tons, it is evident that it can be
raised with great velocity.
The stroke of the piston in the cylinder is 5 meters. This height
of fall, multiplied by the 100,000 kilogrammes of the mass, gives a
working force of 500,000 kilogrammeters, or about 1,640 foot tons. The
width between the legs is 7.5 meters, and the free height under the
cross ties 3 meters, thus providing ample space for maneuvering large
masses of metal.
The entire height of this colossal structure from the base of the
masonry foundation to the upper part of the steam cylinder is 31
meters (102 feet), but notwithstanding this unfavorable condition for
stability and the enormous effect resulting from a shock of 500,000
kilogrammeters, everything is so well proportioned that there is but
slight vibration.
The workman who maneuvers the hammer is placed on a platform on one
of the legs, about 3 meters above the floor. He is here protected
from the heat reflected from the mass of metal during the operation of
forging.
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