We take the following description, together with the illustrations, of
a method and machine for making steel chain without welding, from our
valued contemporary, _Le Genie Civil_, of Paris:
When we regard an ordinary oval-linked chain endwise, it presents itself
in the form of a metal cross, and it was this that gave the cue to M.
Oury, of the Government Arsenals, to construct chain without welding. By
a series of matrices and punches, etc., he contrives, with small loss of
metal, to model a chain out of cross-shaped steel bar.
Steel is the better material for such usage, from its homogeneity, both
as to composition and strength.
Referring to the plate below, Figs. 1 to 10 explain the successive steps
from the bar to the finished chain.
Fig. 1 shows in plan and section the steel bar, whose length may be some
40 feet, and which would make a chain say 50 feet long. The shape of the
bar presents no difficulties in the way of rolling.
Figs. 2 and 3 give, in side elevations of the two faces and sections,
the first rough form of the links. These first begin to take the
exterior shape with the rounding of the angles.
The operations following, represented by Figs. 4 and 5, is the piercing
of the center of the links, which can later be furnished with a stay for
such chains as require special strength. The point now is to detach the
links, which is accomplished by oblique piercings, as shown in Fig. 6.
In the operation represented by Fig. 7, the oval shape is imparted to
the link, and the operation finishes as shown in Fig. 8.
Actually, the links are circular and separate. This separation is
retarded as much as possible, for it is plain that it is easier
to operate a rigid bar than a chain, above all when the operation
necessitates its being pushed forward.
By means of a good system of heating, analogous to that employed on the
large parts entering into ship construction, it is hoped to perform a
major part of the operations, of which we have given but an idea, at a
single heat.
[Illustration: MACHINE FOR MAKING CHAIN WITHOUT WELDING.]
These operations require work on both faces alternately--this presents
no difficulties; but what appears to us most difficult to realize is
_continuous work_, the bar passing through several machines which
successively impress upon it the steps of progress toward the finished
chain. If the machines are end on to each other in a direct line, there
will necessarily be a fixed place for each tool; the rough cut chain
must accurately reach the point where another tool is ready to continue
the modeling. This appears to us practically impossible, the more so as
the elongation which the bar takes at each stamp varies with its initial
diameter.
What is more admissible is that with one heat and in the same machine an
operation could be performed on the two faces perpendicularly. The bar
could then be taken from one furnace and put in another immediately,
to pass at once to another machine to again undergo the operations
following. The work could then be done rapidly, submitting the bar to
several heats.
A few words on the tools as they exist.
The most important principle to note, and on which the different
machines employed are designed, is this: The punches or matrices acting
on the chain at its different points of progress are put in motion by
spiral springs worked by means of tappets or cams distributed over the
circumference of a cylinder, having a rotary movement imparted to it by
pulleys and belts.
The figures on our plate show with sufficient clearness the working of
one of these machines. It will be seen that the bar traverses through
and through the machine for stamping, and that it can be disengaged for
a reheating before passing to subsequent operations.
* * * * *
The bog peat of Mexico is now being used on a considerable scale as fuel
for locomotives, stationary engines, smelting purposes, smiths' fires,
and househould use. The peat is mixed with a proper proportion of
bitumen, and is said not only to burn freely, and without smoke in much
quantity, but to give a higher dynamic equivalent of heat than the same
amount of wood.
* * * * *