The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1869-04-22
CITY TTTTELLIGENCE.
THE FRANKLIN INSTITUTE.
TH.a Meeting Last EveniBg-The Gunpowaer
49, Forge Hammer.

7He Meeting Last Eyening-1'he Gunpowaer
Forge Hammer. -,
me meeting being called TO order with Nj Uoie.
nam Sellers In the chair after the usual Dus.ness
MI Thomas Shaw, at the request sr Sd ,n" and de-
seYibeA Il as follows:- ,., . .o,,oh,o
the object Of this invention s to furnish
appliance for the forging Of large and homogeneouS
masses Of metal One Of cheap CONSTRUCTION esnH snH
management, compact and All pTweanTht esnhstitutinS
these points executing anu cohpNeiy S""'o
The engine is constructed in this wise The Iou9ua o
,,on 70 an anvil block secured 20 Whlch are TWO
.uide pillars between which the hammer " secured @
and guided. Also secondary anvil wlcu 1l S thc
nonded in,mediatey over the anvil blOck, the
weight of this secondary anvil being supporten on
two air chambers which WIZ De @ neIeivr ~ d With
the usual forging dies, varying with the Kline OF Work
NJ tnn of this secondary anvil terminates in
sxinder Of a diameter corresponding in size with the
pIunger OF the lower end OF the hammer or ram.
The metal to be forged is squeezed ana pouhVeu
hetyeen these two anvis, and as there is consider
Se weight the secondary anvil it necessary that
Il should be supported OFF from the work when not
IN operation. For this purpose the ar chambers are
crowded These consist OF two plain brass cylinders
ARMY secured to the guide pillars open at the top
for the reception OF the piston rods and pistons
6ttng the bore Of the cylinder, making ught JOINT,
Wy what s known as hydraulic packing. Inc upper
ends of these piston rods are secured to crosshead
from the secondary anvil. M
entirely out OF the cylinders and then allowed 10 ue
scend in them again, they would compress the ar In
The cylinders, until 1t was suhcienty contracted 10
cause pressure equal to the weight 1t mas 10 sup
In case the bulk q air great thus supporting
the anvil, too high above the work, safety valve
ie provided the spring of which Is controlled by
thumb screw, which can be 30 regulated that the
secondary anvil can be supported al any ucsueu us-
nine connects the two air chambers, causing the
pressure to be the same in each As air escapes
from the safety valve, however, there would be
danger OF having II all lost, were tnere no provision
FOR lis renewal but this provision is made in the fol-
lowing manner:-There is great pressure of air and
gas, at every stroke of the hammer IN the cylinder Oh
the secondary anvil; here is an ineXhaustole supply
af mir rondU
sary is to tap this cylinder by pipe connected WIN
the piston rod, which is made hollow for the passage
Of the gas This pipe is provided with an adJustaoIe
check valve for the retention OF the gas.
BY means Of this supply, and safety valve, the
The hammers caught and held between the guides
by long friction rod, secured by pivOted arms to
friction rod is pulled down the distance beween the
guides is diminished, causing pinching upon and
friction to the hammer sufficient TO arrest aud hold
its weight suspended.
IL will be observed that this action only
the down stroke for the up stroke pushes the friction
rod in direction to diminish the friction, allowing
the hammer to ascend freely, but holding it against
any attempt to descend gnd thus playing very I'M
pOrtant part in the operation of the engine.
addition to this automatic action OF the irlcton
rod it is completely under the control OF the opera
tor by means OF lever connected WIN the same
rod by which it can be held entirely out of touching
distance OF the hammer, or can he made to eaten
the hammer at every stroke.
The platform is placed some is or 20 feet above
the ground and on it there is sufficient room for the
engineer and fireman to operate. 1he PLATFORM
placed at this distance permits the smiths To nave
fau room to operate without interfering with the
engineer.
* piston rod and piston arc held suspended from a
cross beam at the extreme top OF the guide pillars
and top of the hammer is bored for the reception
Of the piston The object of this is to form an air
cushion to arrest the hammer and throw II violently
down again when doing heavy work.
The hammer is worked in this wise:-A small car
fridge of powder is thrown in the cylinder of the
secondary anvil, and then the hammer Is released
and allowed to fall, forcing its punger into the cy
Under, exploding the powder, which drives the ham
ner up again, and at the same time forces the
secondary anvil violently down upon the object to be
forged thus producing pressure OF 10000 pounds
for every square inch Of area of the pllnger; and
this pressure is continued for prolonged PERIOD as
compared with ordinary pounding, and snords the
kind OF pressure that is necessary for the production
OF homogeneous fOrgingS
1t will be observed that the inertia of the second
airy anvil is overcome before the explosion Of the
powder, by reason OF the pressure OF the confined
air forcing the anvil down upon the mass, the speed
thus obtained considerably augmentlng the force or
the blow.
II is estimated that hammer falling twenty feet,
weighing 5000 pounds, provided with plunger six
teen inches diameter entering a chamber forty
inches deep, ignitng one-fourth pound charge of
powder, will cause blow to be struck equal to a
dead pressure of 35O0O0O pounds sufficient i'll fact,
10 forge our largest cannon, and equal in effect to
Krupps famous steam hammer of 125 TONS which
cost fully ten times much the above apparatus.
The report OF the resident secretary Professor Nor
ton, on Novelties in Science and the Mechanic
Arts, including an account Of many important dis
cOveres which have lately been made i'm these de-
partments, was then read, after which the various
committees on the library, models, etc, were ap-
pointed, and the meeting adjourned