IMPROVEMENTS IN HARDENING HOLLOW STEEL ARTICLES, AND IN APPARATUS EMPLOYED FOR THAT PURPOSE
Year: 1879

page_text: LETTERS PATENT to Charles Denton Abel, of Southampton Buildings, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN HARDENING
HOLLOW STEEL ARTICLES, AND IN APPARATUS EMPLOYED FOR THAT PURPOSE."
A cominunication from abroad by Wilhelm Lorenz, of Carlsruhe, in the German
Empire.
Sealed the 27th June 1879, and dated the 10th January 1879.
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel nt the
Office of the Commissioners of Patents on the 10th January 1879.
CHARLES DENTON ABEL, of Southampton Buildings, in the County of Middlesex.
"IMPROVEMENTS IN HARDENING HOLLOW STEEL ARTICLES, AND IN APPARATUS
EMPLOYED FOR THAT PURPOSE." [A communication from abroad by Wilhelm
Lorenz, of Carlsruhe, in the German Empire.]
In the ordinary process for hardening hollow steel articles, by which these when
heated aro cooled simultaneously and equally on their inner and outer surfaces, tho
contraction of the material cannot take place proportionately to the radially
decreasing sections in the direction from the outside to the inside, and unequal
tensions are thus produced in the article, whereby when the inner hardened surface
once becomes worn the article is rendered useless.
By the use of the present Invention such tensions are prevented, so that a hollow
steel tool or dye can be re-hardened 20 to 30 times without deterioration, the action
being such that the tool or dye at each hardening is caused to contract in pro-
portion to the thickness of its sides, so that when the inner surface has become
worn the inner space is brought to the proper dimensions again merely by the
shrinkage caused by the act of hardening.
For this purpose the water for cooling is applied partially to the inner surface
and partially to the outer surface, and according to tho thickness of the article it is
applied either simultaneously in regulated quantity to both the inner and outer
surface, or first only to the outer surface and then quickly to the inner surface, or
first to the inner and then to the outer surface, causing the same water that has
acted on the one surface to act on the other.
The hollow steel articles are for this purpose placed in specially formed recep
tacles, in which they rest upon thin supports, so that the water flowing down through
гр.

page_text: the interior can find its way underneath the lower end and up between the outer
surface and the sides of the receptacle.
The apparatus for carrying out the above described process consists, firstly, of
the above mentioned receptacle, which may be in two or more parts, according to
the form of the article to be hardened; secondly, of a discharge pipe supporting the
said receptacle, through which the water after having done duty is conducted
away; thirdly, of a stand having a dish shaped top for receiving any water that
may overflow the sides of the recoptacle, and that conducts it through channels
into the said discharge tube; and, fourthly, of a nozzle carried by a bracket at the
top of the stand, through which the requisite water is supplied. The discharge
tube is carried by a treadle pressed upwards by a spring, and in commencing
operations the tube is drawn downwards by means of the treadle, thereby lowering
the receptacle to allow of the introduction of the heated steel article. The tube
and receptacle are then pressed upwards by the spring, so as to cause either the
upper open end of the steel article itself or the upper end of the receptacle to abutt
against the end of the nozzle, the lower part of which is removeable, so that nozzles
of different forms corresponding to those of steel articles or of the receptacle can
be used. The upper part of the nozzle contains a valve which is screwed up or
down so as to regulate the quantity of water admitted to the receptacle, and its
lower end contains a loose removeable stem, held centrally by wings, and having a
conical piece screwed on its lower end projecting somewhat beyond the nozzle, so
that by screwing such conical piece farther in or out the water may either be spread
on issuing from the nozzle so as to flow both over the inner and outer surfaco of
the steel article, or it may be concentrated so as to flow only through the interior
thereof.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Denton Abel in the Great Seal Patent Office on the 9th
July 1879.
CHARLES DENTON ABEL, of Southampton Buildings, in the County of Middlesex.
"IMPROVEMENTS IN HARDENING HOLLOW STEEL ARTICLES, AND IN APPARATUS
EMPLOYED FOR THAT PURPOSE." A communication from abroad by Wilhelm Lorenz,
of Carlsruhe, in the German Empire.
In the ordinary process for hardening hollow steel articles, by which these when
heated are cooled simultaneously and equally on their inner and outer surfaces, the
contraction of the material cannot take place proportionately to the radially
decreasing sections in the direction from the outside to the inside, and unequal
tensions are thus produced in the article, whereby when the inner hardened surface
once becomes worn the article is rendered useless.
By the use of the present Invention such tensions are prevented, so that a hollow
steel tool or die can be re-hardened 20 to 30 times without deterioration, the action
being such that the tool or die at each hardening is caused to contract in pro-
portion to the thickness of its sides, so that when the inner surface has become
worn the inner space is brought to the proper dimensions again merely by the
shrinkage caused by the act of hardening.
For this purpose the water for cooling is applied partially to the inner surface
and partially to the outer surface, and according to the thickness of the article it is
applied either simultaneously in regulated quantity to both the inner and outer
surface, or first only to the outer surface and then quickly to the inner surface, or
first to the inner and then to the outer surface, causing the same water that has
acted on the ono surface to net on the other.
The hollow steel articles are for this purpose placed in specially formed recep-
tacles, in which they rest upon their supports, so that the water flowing down through
the interior can find its way underneath the lower end and up between the outer
surface and the sides of the receptacle.
The apparatus for carrying out the above described process consists, firstly, of
the above mentioned receptacle, which may be in two or more parts, according to
the form of the article to be hardened; secondly, of a discharge pipe supporting the
said receptacle, through which the water after having done duty is conducted
away; thirdly, of a stand having a dish shaped top for receiving any water that
may overflow the sides of the receptacle, and that conducts it through channels
into the said discharge tube; and, fourthly, of a nozzle carried by a bracket at the
top of the stand, through which the requisite water is supplied. The discharge
tube is carried by a treadle pressed upwards by a spring, and in commencing
operations the tube is drawn inwards by means of the treadle, thereby lowering
the receptacle to allow of the introduction of the heated steel article. The tube
and receptacle are then pressed upwards by the spring, so as to cause either the
upper open end of the steel article itself or the upper end of the receptacle to abutt
against the end of the nozzle, the lower part of which is removeable, so that nozzles
of different forms corresponding to those of steel articles or of the receptacle can
be used. The upper part of the nozzle contains a valve which is screwed up or
down so as to regulate the quantity of water admitted to the receptacle, and its
lower end contains a loose removeable stem held centrally by wings, and having a
conical piece screwed on its lower end projecting somewhat behond the nozzle, so
that by screwing such conical piece farther in or out the water may either be spread
on issuing from the nozzle so as to flow both over the inner and outer surface of
the steel article, or it may be concentrated so as to flow only through the interior
thereof.

page_text: Figure 3 of the Drawings shews a vertical section of the complete apparatus
above described on the line A, B, of the plan at Figure 5, and Figure 6 shews a
sectional plan on line C, D, Figure 3. Water is supplied through the pipe R to the
nozzle, the construction of which is shewn to an enlarged scale in the vertical
section at Figure 4. This nozzle is supported by three supports x fixed to the
dish d, Figure 3. Immediately below it is the receptacle S, into which the steel
article to be hardened is introduced, and below this is the escape pipe R', through
which the water entering at R is conducted away after use. The pipe R', together
with the receptacle S, supported by the treadle T¹, so that by depressing the
latter the pipe and receptacle are lowered for introducing the steel article, while
when the latter is being operated upon the pipe and receptacle are pressed upwards
so that the latter bears against the nozzle g.
The hardening process is now carried on as follows:-The steel article being
placed in position, as indicated at Figures 1, 2, and 3, the valve K (Figure 4) is
opened more or less by turning the screw by means of the handles h so as to admit
a regulated quantity of water, which for simple cylindrical articles flows through
the nozzle, Figures 3 and 4, into the interior of the article, directly into the pipe R¹,
as at Figure 3, while any portion required for cooling the outer surface flows over
the upper edge on to the dish d, and thence through the openings e into a funnel O
attached to the pipe R', into which it flows through perforations, as shown. For
steel articles of more complex configuration, such as arc, for instance, used in the
manufacture of metal cartridge cases, a nozzle is employed of the construction shewn
at g, Figures 1 and 2, which has within it a cylindrical rod i held centrally by
ribs m, and having at its lower end a screw thread on which is screwed the conical
piece a. By screwing this picce inwards or outwards the area of the annular
orifice is decreased or increased, and the stream of water issuing through it is
directed either more to the outer surface or more to the interior of the steel
article b, according as the peculiar form of the article may require. Thus at
Figure 1 the steel article b is first cooled internally by the stream of water, which
then partly flows underneath the bottom thereof and up over its outer surface,
escaping over the edge of the receptacle, while the remainder escapes directly
through the hole in the bottom of the receptacle into the pipe R'. At Figure 2, on
the other hand, the water flows simultaneously through the interior and over the
outer surface of the steel article. The receptacle S is in this case closed at bottom,
and fits with a projection P into the hole P' (Figure 1) in the top of the pipe R¹.
It is screwed into the piece S' on which the nozzle bears, and in which is formed a
circular channel u, that together with the vertical channels r cut in the screw thread
serve for the escape of the water, as shewn more clearly in the cross section on
line E, G, at Figure 9. Thin ribs or supports n, n, are provided in the receptacles S
for the steel articles to rest on, as shewn.
Figures 7 and 8 shew cross sections taken respectively on lines H, I, and L, N,
Figure 4.
Hollow dies or tools hardened by the above described process are subject to no
strains in the body of the metal, and by means thereof the hardening process may
be repeated from 30 to 50 times, thereby utilising the resulting contraction at every
operation to again reduce the internal diameter to the requisite dimension after it
has become enlarged by wear.
Having thus described the nature of the said Invention as communicated to
me, and the manner of performing the same, I would have it understood that I
claim,―
First. Hardening hollow steel articles by causing a stream of water to pass first
through the interior of the article and then over the outer surface thereof, substan-
tially as herein described.

page_text: Second. The use for hardening or shrinking hollow steel articles of apparatus
wherein the steel article is placed in a receptacle in which it is subjected to the
action of a regulated stream of water directed by a nozzle either into its interior
or simultaneously into its interior and over its outer surface, substantially as herein
described with reference to the accompanying Drawings.
Third. Effecting by the hardening process set forth in the first claim the reduction
to the required dimensions of the internal diameter of hollow steel articles that have
become enlarged by wear.
Fourth. In apparatus for hardening steel articles, the combination of the water
supply nozzle g, receptacle G, pipe R', and dish d, arranged and operating substan-
tially as herein described with reference to the accompanying Drawings.
In witness whereof, I, the said Charles Denton Abel, have hereunto set my
hand and seal, this Ninth day of July, in the year of our Lord One thou-
Band eight hundred and seventy nine.