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February, 1925
The loss due to improper firing is practically negligable,
amounting to under y2 of one per cent in the experience
thus far. Larger shells, 20^ in. square by 4
in. in depth, are handled with satisfactory speed, the
production of these pieces at this time has not been in
sufficient volume to determine accurately what can be
expected in the way of output.
It will be apparent that the furnace is remarkably
successful, both from the standpoint of rapidity of
operation as well as the almost entire absence of loss
due to improper firing. Once the proper speed of the
conveyor and the proper heat of the furnace is found
for a certain part, the results are entirely uniform.
The furnace was built and installed by the Electric
Furnace Construction Company, 1015 Chestnut Street,
Philadelphia, Pa.
Solving the Problem of Die Costs
The shop management frequently encounters difficulties
in satisfying the demand for both economy
and time saving in production. In some cases, for
example, the necessarily limited demand for a product
will not warrant the expense attached to the machining
of a steel die for quantity production; at. the same
time, the demand may be sufficient to make the method
of built-up construction not only very expensive
but a time losing proposition as well.
In instances of this kind, the difficulty can be solved
at times by making the dies of cast iron rather than
of steel. In this manner the high cost of machining
is greatly reduced and at the same time a die is produced
that will take ample care of the manufacturing
needs. This is true particularly of the larger size dies.
An example of the above is shown in the accompanying
illustration of a cast iron die designed and
manufactured by the Buffalo Forge Company, of Buffalo,
for stamping the steel hearths used with their
general repair forges. The object here was to keep
the cost of the die as low as possible. The forge
hearth in question has an overall size of 24 in. x 30
in. and is rectangular in shape. The depth is 5y in.
On two opposite sides is a cut-out section to allow
long bars to lay across the forge and at the same time
to rest in the fire. The four upper corners of the
hearth have a 3 in. radius, while the bottom corners
have a \y2 in. radius.
It has been the practice up to very recently to make
these hearths or bowls of built-up construction. The
great amount of labor and time entailed, however,
made this procedure a costly one. The first operation
under this method was to shear the plate, then notch
the corners and recess the cuts in the side. Followed
by flanging of the sides for the box forming and then
the riveting of angle irons to reinforce the edges. In
the center of the hearth was placed a steel plate, also
for reinforcing purposes.
By employing a die, however, all of the individual
operations are eliminated; a single down stroke of the
press produces the finished hearth. The new forming
die is built-up of six castings made of close grain iron;
three castings comprise the female section and three
the male. The castings for the latter consist of a flat
plate 2 in. thick with the punch fastened to it with
eight bolts, while the pressure ring fits over the punch.
The female section consists of a flat plate \y2 in. thick
to which the forming die itself is fastened. The ejector
plate fits inside the die. The reason for building the
Fbrging-Stamping - Heat 'Beating
die in two sections was due to difficulties in machining
when made in one solid casting. A one-piece section
could only be machined with a vertical mill and this
required the expenditure of considerable time and labor.
By building it in two sections, the machining
operations entailed were of the simplest kind. Another
advantage to be noted is the ease with which
this die can be enlarged if desired without discarding
any of the old castings.
At each corner there is a steel insert fastened in the
die; these inserts were bored and turned in the lathe
and pack hardened. The die was then put on a boring
mill and the corners bored out and the recess cut
for the steel insert. These inserts are held in place
by two bolts each. Because of the great wear and
strain on the corners of the die, it was deemed advisable
to have these inserts in order to prolong the
life of the apparatus. After the inserts were fitted,
the die was put on the planer and the sides finished.
It should be mentioned here as well that there are two
steel inserts in the die at the point where the cut-out
One piece pressed steel forge hearth.
sections in the sides of the hearth are placed. The
sides of this bowl are made 5 deg. taper in order to
facilitate stacking; the stock used is heavy gauge
pickled steel plate.
A single acting press is used for this operation;
pneumatic air cushions operating with an air pressure
of 40 lbs. are used beneath the press to keep the
stock from wrinkling. It is estimated that this die
will be good for 1000 pieces before repairs are necessitated.
In addition to now having a die at a reasonable
cost, which will save considerable time and labor
charges in production, the manufacturer is now enabled
to produce a hearth that is not only more durable
than the older design, but one that is vastly
improved in appearance as well.
Orders received by the General Electric Company
for the three months ending December 31 totalled
$80,009,978, an increase of 7 per cent over the same
quarter in 1923, according to figures made public by
Owen D. Young, chairman of the board of directors.
For the year 1924, orders totalled $283,107,697, as
compared with $304,199,746 for 1923, a decrease of 7
per cent. ,„
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