Vol. LXVIII, No. 2.]

AND RAILROAD JOURNAL. 87

closing and then transferred to the rivet. I have a letter from
Mr. John T. Boyd, in which he speaks of hydraulic rivet-
ing as being preferable when it can be used, and recommends
a plate closer when there is not absolute certainty of the rivet-
ing machine making tight work without it. He also favors
an accumulator in which the weights can be dropped to vary
the pressure applied to rivets on plates of varying thickness
as opposed to one which furnishes uniform pressure for all
kinds of work. He quoted excellent results obtained in rivet-
ing with pressures not exceeding 20,000 lbs. per square inch
of area covered by the formed head of the rivet, but believed
that the make of rivets and the thickness of plates should be
taken into account to secure the most satisfactory results. A
great degree of uniformity in heating rivets can be obtained
with an oil or gas furnace.

Mr. James Christie : I may say that we 11ave found in bridge
Work, in driving rivets of —Z- to 1 in. diameter through thick-
nesses of 5 or 6 in., that it was best to use a plain bar and
form a head on both ends at the same time.

Mr. John Birkinbine: From what has been said it would

lllllltllifilltl
I

  

24-INCH GEAR PRESS, BUILT BY WATSON & STILLMAN. .

seem that the most important feature—namely, the quality of
the iron in the rivets, is often neglected in its considera-
tion; but in locomotive boiler and in bridge work, where
many lives are dependent upon it, it would seem" that noth-
gng but the best quality obtainable should be considered as fit
or use.

Preserving Tools from Rust.—A good plan for preserving
tools from rusting is the simple preparation employed by Pro-
fessor Olmstead, of Yale College, for the preservation of scien-
tific apparatus, and which he long ago published for the gen-
eral good, declining to have it patented. It is made by the
slow melting together of six or eight parts of lard to one of
resin, stirring till cool. This remains semi-fluid, ready for
use, the resin preventing rancidity and" supplying an air-tight
film. Rubbed on a bright surface ever so thinly it protects
and preserves the polish effectually, and it can be wiped elf
nearly clean, if-ever desired, as from a knife blade, or it may
be thinned with coal oil or benzine.—-Royal Engz'neers’ Journal.

4
+

PROJECTILE AND GEAR PRESSES.

 

THE United States Projectile Company, a portion of whose
machinery is illustrated in another column. is engaged not
only in the manufacture of rapid-fire, solid drawn projectiles

of 4, 5, and 6 in. diameter for the United States
Government, but also of gears and pinions for
usage in certain places where the service is very
severe. We illustrate herewith two presses
which were made for them by Messrs. Watson
V & Stillmann, the l1ydraulic machinery manufac-
turers of New York. ’

The larger of the two presses shownhas a cyl-
inder 24 in. in diameter and 48 in. double-acting
stroke, and the smaller have 10 in. and 16 in.
rams of 48, 60, and ‘'12 in. stroke. The larger is
intended for gear work, and is used in forcing
the blank of the gear through the dies from
which it emerges compressed and finished.

The smaller presses, although less powerful,
are doing the more interesting work. The heated
projectile blank is placed beneath the ram and
forced through dies which it leaves true in shape,
straight, and ready for the trimming machine,
which is illustrated in another column. The gen-
eral construction of these presses is very clearly
shown inthc accompanying engravings. The up-
right cylinder is supported by two columns, one
on either side, giving a free opening beneath for the
handling of the material. The head of the ram
has a cross-head with adjustable bearings guid-
ing upon the upright. The end of the ram has
a special shaped head for clamping the drawing
tools to it. The accessibility of the packings is
a prominent feature of the press design. The
valve which is located upon the right of the press
is in one of them beneath the level of the floor
and is of peculiar construction, the valves being
so balanced that they are readily operated and
cause no trouble whatever.

The larger of the two presses is provided with
. a safety-valve on the top, so as to prevent ex-
cessive pressure. These machines are very power-
-ful and occupy very much less floor space than
those which were previously in use by the Pro-
jectile Company. The pressure of 2,500 lbs.jto
the square inch, which is used; gives upon the
ram of 16 in. in diameter apressure of 502,655
lbs. , and on the 24—in. press the enormous pressure
of 1,130,975 lbs.

In addition to the large accumulator carrying a
heavy pressure there is one carrying a lower
pressure of, say, from 100 to 125 lbs. to the square
inch, and this is so arranged in connection with
the valves that the plunger can be brought down
to the work or to a point at which it begins to
force the shell or the gear through the die. Thus
this movement is accomplished without exhaust-
ing water which has been pumped into the ac-
cumulator under a pressure of 2,500 lbs. to the
square inch, saving a considerable amount in
foot-pounds of power.
operated in full force it is considered that this
duplication and use of low-pressure system will
effect a saving of more than 2 tons of coal per
da . '

The makers ilre not ready as yet to publish the details
of this valve. but we hope in a future issue to be able to
show the complete construction. It will be seen from the
engravings that there are three valves held down by springs
and operated by the lever moving through a quadrant on the
side of the machine.

When the plant isx.