Improvements in and relating to Built Up Breech-loading Ordnance, and Apparatus for Use in the Assembling and Separation of the Parts of the same.
Year: 1895

page_text: Date of Application, 25th June, 1895-Accepted, 10th Aug.,
1895
COMPLETE SPECIFICATION.
[Communicated from abroad by WILLIAM SELLERS, of Fairmount Station, in the
City and County of Philadelphia and State of Pennsylvania, United States of
America, Mechanical Engineer.]
Improvements in and relating to Built Up Breech-loading Ordnance,
and Apparatus for Use in the Assembling and Separation of the
Parts of the same.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
In the progress of the art of making built up guns, the tube has from the
beginning been in one piece, but at first, it was comparatively short, and was
reinforced by additional metal in normal condition. An explosion would expand
the bore, and this expansion would reach the outer portion of the gun with
continuously decreasing intensity, so that the outer layers would be scarcely
strained. This was remedied, by shrinking the reinforce, in short cylinders, upon
the tube, so that all the metal in the reinforce would be in tension, and the tube
under it in compression, whereby all the metal in both would instantly resist all
strains at right angles to the bore.
In the modern breech loading gun to which my improvements in the art of
constructing are more especially applicable, the tube remains the basis upon which
the gun is built up, but it is very much longer than its predecessor. It is of forged
steel in one piece, and it is bored to suit the diameter of the projectile to be used
therewith. The breech end of the bore is enlarged to form a powder chamber,
while the exterior of the tube is cylindrical, and usually of several diameters, the
smallest at the muzzle. This tube is reinforced by a jacket at the breech and by
several hoops between the jacket and the muzzle of the tube, the first of which abuts
against the jacket, the second against the first, and so on to the last. The jacket
and the hoops are shrunk upon the tube, so that they will be under a strain to a
limited extent when in place upon the tube. The thickness of the tube being
determined, this strain is regulated by the difference between their interior
diameters, and the exterior diameter of the tube, when they are all at the same
temperature. In the larger guns, this first series of reinforcements, is supplemented
by a second series, which is shrunk upon the first in the same manner, that the first
series is shrunk upon the tube, so that such guns, are composed of a very large number
of separate and independent pieces, but whether the gun is composed of one, or of
more than one series of reinforcements, each series is so constructed, that when
shrunk to place, it is in a state of tension.
In the construction of such guns, each reinforcement must have its ends turned
true, it must be truly bored and the exterior of the tube accurately turned to the
size required, to produce the requisite strain upon each reinforcement when it
is shrunk to its proper place thereon, but it is impossible to shrink on one piece
after another successively and immediately, until the whole are assembled, for it
happens that the ends of the reinforcements are frequently distorted by shrinking
them on the tube, and that the tube itself is also distorted. As it is absolutely
requisite to make good work, that the tube and the squared end of any reinforcement

page_text: shall be true with each other, it becomes necessary to true up both, after each
reinforcement is shrunk in place. When therefore all the parts, tube, jacket and
hoops are properly prepared, the jacket is first shrunk upon its place on the tube,
then the tube and jacket are returned to the lathe, the end of the jacket next the
first hoop is trued up, the seat for the first hoop on the tube is turned to exact size,
the first hoop is then shrunk to place, the tube is then returned to the lathe, the
exposed end of the first hoop is trued up, the seat for the second hoop is turned to
exact size, the second hoop is then shrunk to place, and this process is repeated
with each successive hoop until all are assembled upon the tube. All of this
involves a great deal of time and care by highly skilled mechanics, in the preparation
of the several parts, while the work of assembling must necessarily be slow, and the
handling excessive. In this form of gun the tube is supposed to be strong enough
in itself, to resist all of the bending and longitudinal strains that can come upon it
in service. The jacket and hoops of these guns are reinforcements provided to
resist the bursting strains alone, for as the hoops merely abut against each other, or
are imperfectly locked together, they can add little to the strength of the tube as a
beam, and practically nothing to its longitudinal strength.
Very many experiments in the ordnance departments of the world have been
made and are now making, upon wire wound guns, such reinforcements, while
affording perhaps superior resistance to bursting strains, are less effective even, than
jacket and hoops for imparting beam strength. Experiments of this character, in
connection with the now universal practice of reinforcing with jackets and hoops,
show that the necessity for increasing the beam strength of the gun has not been
recognized, or that the means for accomplishing it are unknown.
As guns become larger, the transverse stress due to the weight of the gun,
increases faster than the strength to resist it, the deflection of the muzzle increases
in a still greater ratio, for with similar guns the droop at the muzzle will be as the
square of the diameters of the bore, that is, a sixteen inch gun, will droop four
times as much as an eight inch, and with guns of the same diameter and bore but
of different lengths with a weight proportional to the length, the droop at the
muzzle will be as the fourth power of the ratio of the lengths, that is, if one gun is
twice as long as the other, the droop of the long gun will be sixteen times that of
the short gun. When a long modern gun is mounted it will droop at the muzzle
from its own weight, and its bore will be a curve, when it is fired, the shot will tend
to move in a straight line and cause the muzzle to whip, the amplitude of the
whipping in similar guns will be approximately as the squares of the bore, and as
short hoops have comparatively slight adhesion, the whipping action, with the shock
of the explosion, will cause the joints between the several hoops and the jacket of
the reinforce to open. While the hoop reinforce does not materially strengthen the
tube against this whipping action, the weight of the hoops themselves, increases the
tendency to droop and adds momentum to the whipping action, which may thus
give the tube a permanent set, a result that has been attained on some of the larger
modern guns in a few rounds. The necessity for increased beam strength in the
great guns now required is therefore evident."
In the process of assembling such guns by shrinking one part upon another as
heretofore practised, the part to be heated is placed in a heating chamber or in a
furnace, and its temperature raised the required amount. It is then removed from
the heating chamber and transferred to and imposed upon, the part designed to
receive it. In this removal, transfer and imposition, it is losing heat, and this loss
may by accident or by carelessness, be protracted so as to cause it to seize the
piece prematurely, upon which it is being imposed. If the heated part which is to
be imposed upon the part designed to receive it, should from any cause seize or
shrink upon that part, before it has reached its proper position, there has been no
means provided heretofore, for releasing and removing it, nor have any means been
devised, for separating the parts of a built up gun, after such parts have been
properly assembled by shrinking one part upon another. If seizure should occur
prematurely, in the process of assembling, the only remedy has been, to cut off the

page_text: part which has seized, and replace it with another. Heretofore also, in the case of
properly assembled guns, the whole gun was condemned, when the tube had burst,
or had become too much worn, or had otherwise been damaged so as to be unfit for
service, and all parts of the gun were then valueless, except for scrap.
The objects of my improvement therefore are, to obtain a greatly increased beam
strength without any increase of metal, to simplify the construction, to reduce the
cost, to diminish the time of assembling, to maintain the heat and dimensions of
the heated part during the assembling operation, to separate the parts after they
have been assembled by shrinking one part upon another, and to provide apparatus
whereby these several objects may be accomplished.
To these ends, I make the tube of the gun in one piece of the length required,
with a bore roughed out, approximating its finished size, to suit the diameter of the
projectile to be used therewith, and a jacket in one piece of a length to sustain the
breech plug and to embrace all the surface of the tube which requires to be
reinforced against strains of any kind, a second jacket if the first requires to be
reinforced, the second of a length to embrace all the surface of the first which
requires to be reinforced, and so on until all the metal of the gun is provided, ready
for assembling. For this purpose I provide a portable heating chamber long
enough to contain the first jacket, and strong enough to sustain its own weight
with that of the jacket within it, when suspended from a crane by which it is
transported to and lowered over the tube which is set vertically to receive it. The
second jacket is imposed upon the first by the same means and in like manner, and
When the assembling
provision is made for cooling the tube from the interior.
has been completed, the bore is finished to the proper size. The same apparatus
affords the means for separating the parts of the gun after they have been
assembled by shrinking oue part upon another, as will be more particularly
described hereinafter.
After shrinking this long jacket upon the tube, all the metal of the jacket will
be in tension and all of the tube under it in compression. The tension is produced
by the contraction of the jacket after it seizes the tube in the act of cooling, and
this contraction takes place equally both circumferentially and longitudinally.
The tension is caused by the resistance which the tube offers to the contraction of
the jacket, aud it is limited by the difference of temperature between the jacket
and the tube when the jacket seizes the tube so as not to slip. Circumferential
contraction creates no tendency to slip, but longitudinal contraction will cause slip
until there is sufficient surface under circumferential tension to prevent it, that is,
until the friction between the jacket and the tube, where the circumferential
tension will be at its maximum, equals the longitudinal stress produced by the
longitudinal contraction.
The friction of such metal surfaces sliding upon each other, has been proved
experimentally, to be about 20% of the load, from which it follows, that when
both ends of a jacket are held to the tube by friction alone, it must have a leugth
equal to ten times the diameter of its bore, before a longitudinal tension can be set
up equal to the circumferential, by shrinking it upon a tube. As the circum-
ferential tension is limited by the difference of temperature between the jacket and
the tube when the jacket seizes the tube, it follows that the greatest longitudinal
tension that can be produced in a jacket of the above length, cannot exceed its
maximum circumferential tension, but if the jacket is cooled from the centre.
toward the ends, it may be less, and a lesser length will result in a lesser longi-
tudinal tension. Increasing the length of the jacket beyond ten times the diameter
of its bore, will not increase the longitudinal tension, because this tension has
reached its maximum when the jacket does not slip on the tube, therefore, the
longitudinal tension can never exceed the circumferential with any length of jacket,
unless the longer jacket is cooled at the ends.
From this it follows, that in the jackets and hoops heretofore used, the longi-
tudinal strain is proportional to the length of the jacket or hoop, but with a jacket
or hoop of a length equal to ten times the diameter of its bore, and longer, the
:
:

page_text: longitudinal strain is not proportional to the length of the jacket or hoop. When
the entire length of the reinforce is in one piece, and shrunk upon the tube, all the
metal of the tube in and under the reinforce will be strained in two directions,
circumferentially and longitudinally, that is, at right angles to each other, and
therefore, the metal in the tube can yield only in a third direction, toward its
axis. In this condition the tube will sustain a greater pressure from the reinforce,
and a higher explosive pressure. With an explosion in a gun thus strained,
all the metal of the gun, in and under the reinforce, whether behind or before the
shot, instantly responds to resist it, whereas, in the modern built up gun where
the reinforce is divided into separate sections, which excludes longitudinal strain
throughout the reinforce, an explosion is resisted by the circumferential strain
alone.
As a consequence of my construction, I increase the stiffness of the gun without
any increase of metal, thereby lessening the amplitude of its vibrations when fired,
and as these vibrations require power to produce them, which otherwise would be
expended upon the shot alone, by lessening them I increase the velocity of the shot
with the same charge. I also reduce the time and labor now required for making and
assembling the parts, and I obtain a gun which may conveniently and practically
be taken to pieces and reassembled, after it has been in service, whereby any part
which may have been damaged by such service can be removed and a new part
substituted therefor, so that the original value of the gun may be restored. The
apparatus I have devised for assembling the parts, enables the operator to control
the process of assembling with certainty; to determine before assembling, whether
any reinforcement such as a jacket has been bent in the process of expanding it to
the proper diameter to assemble it; to determine the temperature of any reinforce-
ment throughout its length, in advance of assembling, and enables the operator to
retard or arrest the process of assembling in advance of any disposition to seize
prematurely. In order to assemble the parts of a gun by shrinking one part upon
another when it is constructed as proposed, I have contrived a portable heating
chamber, preferably an iron shell lined with brick, in which one of the parts to be
assembled is heated and retained, until it is in its place on that part of the gun
designed to receive it; a series of centering chucks supported within the
reinforcing piece or jacket to be heated, and a telescope and cross hairs, or their
substitutes, by means of which the alignment of the chucks and consequently the
straightness of the jacket, can be determined at sight, in advance of assembling;
a series of thermometers or pyrometers, and an illuminating apparatus whereby the
temperature at each chuck can be observed through the telescope in advance of
assembling; an index vibrating about an axis fixed to the outside of the portable
chamber and so connected to a contrivance from which the chamber is suspended,
that any resistance to the descent of the jacket and chamber will cause a movement
of the index, and a cooling apparatus by which the inner part can be maintained
at or near its normal temperature, when the heated part is imposed upon it, and by
which all the parts can be rapidly cooled from the interior when required, and
these together constitute the best apparatus known to me for the purpose of carrying
out or working my improvement in the art of constructing such guns.
I will first describe the construction of the gun, referring to the drawings thereof,
and then to the drawings of the apparatus which I have found most convenient for
assembling and for disassembling the parts of such built up breech loading guns.
In order that the details may be shown clearly, a large scale is required, and the
parts of the assembling apparatus showing the gun and the heating chamber are
therefore represented as broken, their great length making it impossible to show
their full length, within the size of a drawing for a Patent.
Sheet 1, Fig. 1, represents a longitudinal section of a built up breech loading
gun of my improved construction. Fig. 2 shows an enlarged longitudinal section
of one side of the same. The breech plug is not shown in these drawings, that
forming no part of my present invention. The arrangement of the several parts
of the gun shown in Fig. 1, is adapted to the interrupted screw for securing the

page_text: breech plug in place, but any other device for securing the breech plug may be
employed, and these parts may be modified to suit the same without affecting my
invention.
In Fig. 1, A is the gun tube, the bore of which is enlarged at the breech end to
form a powder chamber, and this end of the tube is also the largest in its exterior
diameter, the junction between the larger breech end and the smaller muzzle end
of the tube, forming a shoulder shown by the dotted line a a. The jacket B has
a bore conforming to the exterior of the tube A, therefore having a shoulder
which, when the jacket and tube are assembled, rests against the shoulder on the
tube. These shoulders on the tube and jacket determine the exact position of the
jacket on the tube in assembling, and as the breech plug is secured to the jacket
and rests against the tube, when it is in place, the jacket and tube are securely
locked longitudinally in both directions when the gun is fired. The exterior of
the jacket B is turned truly cylindrical at the breech end, for a length nearly
equal to that of the outer jacket C, beyond this it is enlarged to form a shoulder,
shown by the dotted line bb, forward of this it is turned cylindrical for a distance
which in conjunction with the longer cylindrical portion at the breech end, equals
the total length of the jacket C, and beyond this it is turned taper as clearly shown
upon the drawing. The outer jacket C has a bore conforming to the exterior
cylindrical portion of the jacket B, therefore having a short enlarged cylindrical
interior or bore at the end toward the muzzle of the gun. This short enlarged
bore is intended to cover the vertical joint between the outer jacket C and the
jacket B at the dotted line bb and thus prevent the admission of moisture at this
joint. It is made short in order that the enlarged bore can be formed with a
turning tool. The outer jacket C is turned cylindrical upon its exterior except a
small conical portion at the breech end; near the front end it may be reduced in
diameter to form a shoulder for the trunnion ring D. Upon this jacket a screw
thread may be cut to conform to that of the trunnion ring, and beyond this ring
toward the muzzle, this outer jacket is turned taper as shown. The trunnion
ring D is of the ordinary construction, and may be shrunk upon the outer
jacket C, the screw threads and shoulder locking it to place. The section of
this trunnion ring and the shoulders a a and b b are more clearly shown
in Fig. 2.
From the above description of my improved gun, it will be understood that the
tube is in one piece, bored to suit the diameter of the projectile to be used therewith,
and provided with a reinforcement or jacket of such length, that it shall be long
enough to sustain and will support the breech plug, and likewise surround and
strengthen the tube throughout the whole portion of its length which is to be
reinforced. This jacket is shrunk upon the tube, and in this part of the operation
the jacket must be first heated to a temperature which will expand it sufficiently
circumferentially, to pass freely over the tube, but in expanding it circumferentially,
it must also expand longitudinally, and when so expanded it is imposed upon the
tube. As the jacket cools it will shrink or contract and seize the tube; this will
produce tension in the jacket and compression in the tube, which will continue
to increase until both jacket and tube attain a uniform temperature. The jacket
will seize the tube in a few minutes after it has been imposed upon it, but under
natural conditions it will continue to shrink and increase its tension very much
longer. After the jacket has seized circumferentially, it still continues to shrink
equally both circumferentially and longitudinally, and in so doing, the interior
surface of the jacket and the exterior surface of the tube must slide upon each
other longitudinally to permit the necessary longitudinal contraction of the jacket,
The enormous
or the jacket must be extended and the tube must be shortened.
friction of surfaces of such length under the great circumferential strain to which
they are subjected, will cause an extension of the jacket and a shortening of the
tube, but as the longitudinal tension of the jacket cannot exceed its circumferential
tension, and as this latter is determined by the difference of diameter between the
bore of the jacket and the exterior of the tube when both are at the same

page_text: temperature, the degree of stress both circumferentially and longitudinally is easily
determined in advance of assembling. In all of the larger guns, the long jacket
above described, is supplemented by a shorter one, imposed upon the breech end of
the first, and this like the first is in one piece and of such length as to cover all of
the first that requires to be reinforced. This second jacket is shrunk upon the
first in the same manner as the first is shrunk upon the tube, and with like effect,
so that when the gun is thus assembled, all the metal throughout the built up
portion of it, is in stress both circumferentially and longitudinally.
The apparatus by means of which the parts of such a gun may be successfully
assembled by shrinking one part upon another, is shown in the following drawings,
in which Sheet 2, Fig. 3, represents in vertical section, the heating stand with the
heating chamber and the longest or inner jacket of the gun mounted thereon; it
also shows the cover cap for the jacket to prevent the products of combustion from
the furnaces from having access to the interior of the jacket, which cover also
affords means for supporting the centering chucks which are shown within the
jacket, and the means for raising the chucks to their place are also shown. The
furnace is broken away on one side to make room for Fig. 4 which is a plan of
the heating stand. Sheet 3, Fig. 5, represents in vertical section, an assembling
stand with a gun tube and its jacket mounted thereon, inside the heating chamber,
which is shown as resting upon the assembling stand. All of these parts are shown
in the position they would occupy after the jacket has been lowered over the tube.
Fig. 6 is a plan of this assembling stand, showing the cooling pipe in cross section
in its centre. Sheet 4, Fig. 7, is an elevation of the heating stand, with the
heating chamber mounted thereon, also the means for suspending this chamber and
for dividing it so as to convert it into a shorter chamber for heating a hoop or
the outer jacket of the gun. The furnace end is broken away to show the attach-
ment of the furnace casing to the heating chamber casing and the oil supply
pipe between the two. Fig. 8 is a front elevation of the index and its connection
to the contrivance which supports the heating chamber, and Fig. 9 is a side
elevation of this index, showing its connection to the outer shell or casing of the
heating chamber. Sheet 5, Fig. 10, represents in vertical section, the lower end
of the heating chamber, showing its furnaces and their connection with the
chamber Fig. 11 is a horizontal section of the same above the air pipe, and
Fig. 12 is a cross section of the lower end of the heating chamber on the
line AA, Fig. 10, and showing in place, a petroleum burner above its furnace.
Sheet 6, Fig. 13, is a plan of a centering chuck with its pyrometer, with the top
plate removed; Fig. 14 is a side elevation of the same; Fig. 15, is a vertical
section through the centre of the chuck showing in elevation, the chucking bar at
the place where the pyrometer band is cut, and the ring which carries the cross
hairs, mounted on the hub of the chuck; Fig. 16, is a side elevation of one of the
other two chucking bars, which are alike; Fig. 17, is a vertical section showing a
side elevation of the pyrometer index; Fig. 18, is an enlarged plan of the ends
of the pyrometer band and its connections to the index lever, and Fig. 19, is a
plan of the ring which carries the cross hairs.
In Fig. 3, B is the jacket of the gun, resting upon the annular plate al a¹, which
in turn is supported by the flanged ring piece b₁₁ which form a detachable base,
the latter is secured to the interior of the annular oil reservoir C¹ C¹ by a bayonet
joint as shown in this figure but more clearly in Figs. 10 and 12. The heating
stand A' is of cast iron, circular in form, of such diameter at the upper end, as to
support the flanged ring piece 1. The height is such as to afford convenient
access to its interior, through openings J, to adjust the apparatus hereinafter
described as located within it. The base of the stand is enlarged and rests upon a
horizontal foundation, to give stability to the gun and the apparatus which it
supports. The heating chamber D'D' is composed of plate metal cylinders, united
at their ends by hoops as shown in Fig. 7, or of boiler iron sheets secured as in
boilers, the thickness of metal being such as to be capable of sustaining the brick
lining of the chamber and also the entire gun, a part of which is to be heated

page_text: therein. The brick liuing on its interior, is cylindrical from top to bottom, but at
its base and for a short distance above it, the casing is enlarged to provide for a
series of furnaces, Figs. 5, 10 and 12, around the heating chamber. The upper
end of this iron casing, Figs. 7 and 9, is provided with eye bars secured to the
casing and they must be capable of carrying safely all of the above mentioned
weight. To the eyes of each of these bars, a chain is secured by a pin at one end,
while the other end thereof is secured by a large link to the end of one of the
beams Y Y so as to vibrate freely thereon, the length of these chains being such,
that when the heating chamber is lowered over the tube so as to rest upon the
assembling stand, as shown in Fig. 5, neither the cover; nor its enclosed damper i
can come in contact with the beam X hereinafter described. Through the middle
of each of these beams Y Y, a hole is bore to receive a turned end of the beam X
so that the beams Y Y can vibrate freely thereon. The centre of this beam X is
provided with a hole y' to receive the hook from a crane or hoisting device, which
is capable of lifting and transporting the heating chamber with its accessories and
its contents, to the assembling stand. It is important that the jacket shall pass
freely over the gun tube in the act of assembling, and therefore to give notice of
anything which might retard the descent of the jacket, as for instance, undue
friction upon the tube, I provide an index Z, Fig. 8. This index is composed of
an iron pipe or rod of suitable length, upon the upper end of which is secured a
small cap provided with a horizontal hole over the centre of the pipe to receive
a pin fastened in the side of the casing of the heating chamber, see Fig. 9, upon
which pin the pipe can vibrate in a vertical plane. This cap also receives two
brace rods, one on one side of the pipe, the other on the opposite side, and these
brace rods extend downward to the lower end of the pipe to which they are
secured. Between the cap and the lower end of the pipe, are two struts or cross
bars through which the pipe passes, and over their ends the brace rods pass as
shown, so that when these rods are tightened by screw nuts on the upper side of
the cap, the pipe will be rendered very stiff, although the whole may be extremely
light. To the lower end of the pipe is securely fastened a tapered rod, the lower
end of which is drawn down fine so as to indicate accurately its position over the
graduated scale which is fastened to the side of the casing of the beating
chamber directly beneath the pin upon which the index vibrates. A short distance
from the vertical centre line of the index, one end of a light chain is secured to
the cap on the upper end of the pipe, the upper end of this chain being secured
to one of the outer ends of the beani X, Figs. 7, 8 and 9. The length of this chain
must be such, that when the hook of the crane has drawn everything up preparatory
to hoisting, the index shall hang vertical. Whenever actual hoisting is attempted,
all the chains in tension will stretch perceptibly, except the light chain, this will
draw the index out of the perpendicular, and it will so remain as long as the whole
weight lifted is suspended from the crane. If, in the act of lowering the jacket
over the tube, the surface should come in such close contact as to create serious
friction, the load upon the crane would be relieved thereby, the parts in tension
would contract and the index point would move toward a perpendicular position,
the operator would thereby be able to determine whether to continue lowering or
to raise the jacket and increase its temperature, preparatory to another attempt.
The petroleum burners cc for heating the heating chamber D' D' are similar to
those used at present in welding furnaces and are shown in Figs. 5 and 10. They
are supplied with crude petroleum or other suitable oil or gas, from the small
pipe dd, Figs. 5 and 10, the quantity required for each burner being regulated
by the small valve e shown in plan in Fig. 10, in which the pipe which carries the
oil to the burner is also shown. The reservoir of oil C C to supply the pipe d d,
forms the base of the heating chamber D' D', and the oil is conveyed to the
pipe d d by the vertical pipe d' which passes through the upper plate of the
reservoir (in which it is packed so as to be air tight) nearly to the bottom plate
thereof, see Figs. 3 and 7. The air for supporting the combustion of the oil, and
a greater amount if desired, is furnished from the large curved pipe EE; the

page_text: quantity is regulated to each burner by a suitable valve, and the supply is furnished
from a pressure blower or other known contrivance located where most convenient.
The air is conveyed to the pipe E E at f (Fig. 11) by a flexible tube of such
length as will permit the heating chamber to be moved with its contents, the
distance required for assembling, without rupturing or straining this flexible pipe.
From the under side of the curved pipe E E a pipe E' is carried down to, and
passes through the upper plate of the reservoir CC, in which it is packed so as
to be air tight, and the pressure of air supplied to the burners must be at least
sufficient to force the oil up through the pipe d¹ to the burners. The air pipe E¹
and the oil pipe d' pass downward to the oil reservoir through openings between
the furnaces g 9 g, and below these furnaces are openings in the brick work and
through the casing, for packing their passage to the reservoir C¹ C', see Fig. 12.
The oil burns at the lower end of the burners c c, and in the furnaces g 9 9,
Figs. 5, 10 & 12 which are formed in the brick work which surrounds the heating
cavity of the heating chamber D¹ D', and communicates with this chamber by the
openings nnn, Figs. 3, 5, 10 and 12, formed in the brick work, through
which the heated products of combustion pass into the heating cavity of the
chamber D D¹.
Surrounding the lower end of the burners, I provide short cylinders of
metal CC, Figs. 5 and 10, which are open at both ends, the object of which is
to prevent the flame from spreading, and thereby produce a downward current
which will draw air into the furnaces 9 g. In its passage through these furnaces,
this air will be heated by the flamic, so that the discharge into the heating
chamber D' D' will be large in volume but of moderate temperature.
These heated gases and air pass up through the chamber D' D' and have escape
through the opening F, Figs. 3 and 5, which opening is provided with a butterfly
or other kind of damper i, by means of which the requisite pressure can be
maintained within the heating chamber.
The top of this chamber is provided with a large annular cover plate G G, Figs. 3, 5
and 7, the opening in the centre of which, is large enough to permit the muzzle
end of the gun tube to pass through it freely, and to leave sufficient space between
this tube and the cover plate, for the escape of the heated gases from the burners.
This opening in the large cover plate, is covered by a smaller annular cover
plate, Fig. 3, in the centre of which is the above described opening F and
butterfly damper i.
On top of the jacket B is mounted the supporting stand H, Figs. 3 and 5, in
which is placed the pulley k, over which passes the wire or cord 11, one end of
which is attached to and supports the upper centering chuck, while the other
passes through the jacket and chucks around the pulley I in the base of the
heating stand A', and thence up to the drum K, Figs. 3 and 4, to which drum it
is secured, by means of which apparatus the chucks are raised and supported in
position within the jacket.
The upper centering chuck, Fig. 3, is provided on top with a tripod shaped
handle, to which the wire cord is hooked, and inside this tripod an incandescent
light is fixed, the top of which is covered with a case or reflector which confines
the light to the small opening in the centre of the chuck. The electric current for
this light is carried by a wire passing from the heating stand A' through the
openings in the chucks. From the under side of this upper chuck, three or more
chains are suspended, the lower ends of which are hooked into eyes provided for
that purpose, on the upper side of the middle centering chuck. The length of
these chains must be such that when the upper chuck is close to the under side of
the supporting stand H, the middle chuck will be two or three inches below the
shoulder on the interior of the jacket if there be such shoulder, this length being
provided in order that the longitudinal expansion of the jacket by heat, shall not
jam the chuck against the shoulder.
The lower centering chuck is supported upon hinged brackets mm, Fig. 3,
preferably three in number; the hinges are secured to the base plate a¹ a¹ by

page_text: thumb screws n¹ n¹; the inner ends of these brackets mm are provided with fine
threaded screws n¹¹n for adjusting the chuck which rests upon their ends. The
hub Q of this chuck is extended below the nut which clamps the plate P¹ to
the hub, to provide support for a telescope N which is secured to the hub by the
coupling nut m'. This telescope is provided with cross hairs which in conjunction
with cross wires in the middle chuck and a small hole in the centre of the upper
chuck hereinafter described, enable the operator to determine the alignment of the
chucks. These centering chucks are shown in Fig. 3, in proper position for
observing the effect of the heat upon the jacket, and they must be removed before
the heating chamber and the tube of the gun are moved from the heating
stand A. To remove these chucks from the jacket, their centering bars must
first be permitted to draw inwards to release the chuck as hereinafter described,
the drum K is then turned, to lower the upper and the middle chucks so that the
chains on the underside of the middle chuck can be hooked into the eyes on the
upper side of the lower chuck, for which purpose the operator's arm can be passed
through the openings in the chuck, or the chains or rods can be passed through
the chuck and secured to its under side; the motion of the drum K is then
reversed, so as to raise all of the chucks until the lower one is lifted clear of the
adjusting screws in the end of the hinged brackets mm; the thumb screws n'n' are
then released, and the brackets mm are allowed to swing down supported only by
their hinges. On the inside of the heating stand A¹ are three tiers of hinged
brackets oo, three or more brackets in each tier; the inner ends of the two upper
tiers are now raised, until they rest against the inner side of the stand A¹, the
drum K is then turned, so as to lower the centering chucks, until the lower one
rests upon the lower tier of hinged brackets oo; the raised ends of the second tier
of brackets are then lowered so that they will act as brackets or shelves, and the
motion of the drum K is renewed, until the middle chuck rests upon the brackets
of the second tier, the raised ends of the third and upper tier of brackets are then
lowered, the motion of the drum K is again renewed, until the upper and last
The wire or cord is then
chuck rests upon the brackets of the third tier.
unhooked from the last or upper chuck, and a light cord or wire sufficient to
sustain the weight of the cord 7, is attached to this unhooked end of the wire, the
drum K is then turned to wind the wire upon it, excepting a short length which
passes under the pulley wheel I, and rests upon the foundation which supports the
heating stand A¹. The light cord or wire is then drawn over the pulley k
and allowed to fall upon the chucks then within the heating stand A.
To place the centering chucks in the position shown in the drawing, the
movements just described are reversed. Apertures J, Figs. 3 and 7, in the
side of the heating stand give access to its interior, so that the brackets etc.
may be manipulated. The middle one of the centering chucks such as is
above referred to and shown in position in Fig. 3, is shown in detail and on a
larger scale in Figs. 13, 14, 15, 16, 17 & 19, Sheet 6. Each of these chucks
contains a pyrometer, and Fig. 13 is a plan of the same, with the upper cover plate
removed, to show the interior more clearly. The construction of all the chucks is
the same except that the upper one is provided with an incandescent light
on its upper side, and the lower one has a telescope attached to its under
side as herein before described. The frame of the chuck is composed of
four pieces united by screws and nuts as shown in Fig. 15, where 00
let
short tongues
into the
circular steel rin provided with
upper circular
cover plate P and the lower circular cover plate P',
which plates are secured to the rim 00 by short tap screws as shown. At the
centre of these plates is a tubular hub Q, the exterior of which is enlarged between
the plates, to form a shoulder, against which the plates are forced by the nuts pp
which are secured on the projecting ends of the hub Q, thus securing the hub to
the plates. The above forms the frame of the chuck which as thus constructed,
will be both light and very rigid. Between the plates P and P', and secured to P,
1S
a
B

page_text: a
three pairs of supports R R are placed to carry the inner ends of the centering or
chucking bars 97. The supports R R are secured to the plate P by through bolts
or they may he secured in any other suitable manner. Each pair of supports RR
is provided with a shaft r and between each pair, a short lever arm S, is mounted
and firmly secured upon the shaft r. To the other end of this lever arm S the
inner end of a chucking bar q is secured by pin joint, the outer end of the
chucking bar is supported by the rim O O through which a hole is bored, for this
bar to slide freely therein. The three shafts rr are geared together by two
pairs of mitre wheel segments ss ss which are respectively mounted upon and
firmly secured to the ends of the shafts which project beyond the
supports R R R for this purpose, so that the movements of the chucking bars q q
must be through equal spaces. The short lever arm S which is mounted upon the
shaft between two segments ss, is provided with a projecting tail piece so as to
form a bell crank, shown by dotted lines in Fig. 16. To the long arm of this bell
crank, a wire cord t is attached, which cord must be long enough to pass out at the
lower end of the piece to be heated and into the heating stand, so that a weight
may be attached thereto, to force the chucking bars against the interior of the
piece mounted upon the heating stand. As thus arranged, the weight of the cord t,
its bell crank and the mitre wheel segments, all tend to force the chucking
bars 9 9 9 outward, but to place the chucks in the position shown in Fig. 3 it is
necessary that the chucking bars shall be drawn inwards to clear the interior
surface of the piece of the gun in which the chucks are to be placed.
For this purpose, and also for another hereinafter referred to, I provide a spiral
spring T for each chucking bar, and this spring is wound so that the bar can pass
freely through it. One end of this spring abuts against the rim OO and the other
against a collar U or pin, screwed, or secured to the inner end of the chucking bar,
and for the purpose of drawing these bars inwards, the compression of the spiral
springs is required to be slightly in excess of the weight above referred to.
After
the chucks are in the positions shown in Fig. 3, a weight attached to the lower end
of the wire cord t of each chuck, slightly in excess of the sum of the compressions
on the three spiral springs T T T in each chuck, will force the chucking bars out-
ward against the interior of the piece of the gun in which the chuck is mounted,
and centre it truly therein.
The pyrometer is composed of a brass band V V of an exterior diameter slightly
in excess of that of the interior of the piece, the temperature of which it is designed
to measure, and of a width to permit it to play freely between the plates P and Pi
of the chuck. It has a gap in it as shown in Figs. 13 and 14, and on the side
opposite the gap it is attached to the rim O by a pin , which is firmly secured in
the rim O and passes through a hole in the band V V, of a size to fit easily over
the pin. There are oblong holes through the band V V opposite the ends of the
chucking bars 9, so as to permit the bars to pass through it, and to permit the
expansion of the band without affecting the position of these bars. On each side
of these bars are links vv secured respectively to the band V V and the collar U U
by pin joints. The links of the chucking bar 7 which passes through the gap in
the band V are secured to the ends of the band V V on either side of this bar.
All of these links v v are of such length that when the chucking bars qqq are in
contact with the interior of the piece of the gun they are designed to centre, the
band V V will also be in contact with the interior surface of the same piece, and
that this band may not affect the outward movement of the chucking bars, the pin
holes in the ends of the links vv may be cut away slightly toward each other so
that if the band should fail to rest throughout against the interior surface it is
designed for, that is to say, if it should not go out far enough, this will not prevent
the chucking bars from reaching it. The band V V with a gap in it as before
described, acts as a spring, and beds itself against the interior surface of the piece
of the gun and must be drawn inwards like the chucking bars qqq in order that
the chuck can be entered to the positions for them, shown in Fig. 3. For this
purpose the spiral springs T T T are made stiff enough to compress the band V V,

page_text: in addition to the strength required for drawing the chucking bars inward. After
the chucks are raised to the positions shown in Fig. 3, a weight W must be
attached to the wire cord t of each chuck, sufficient to compress the springs TTT
so as to centre the chuck and to permit the band V V to bed itself against the
interior surface of the piece in which it is placed. To permit the cord to pass from
the upper chuck through the two lower ones and from the middle one through the
lower one, I provide the holes t¹¹¹ in each chuck so that one cord shall not
interfere with another. This contemplates suspending the chucks so that the index
plates hereinafter described shall each have one third of a circle in which they
can be placed without one overlapping another as they are suspended one above
another within the piece of the gun, whereby each one will be visible from the
heating stand.
The pyrometer band V V is made of brass which expands under a given
increase of temperature, to a greater degree than the steel of the gun against
which it rests, it therefore follows that when both are heated, the greater
expansion of the brass band will force the ends of the band to approach each other,
and the measure of this approach at each band will afford a correct determination
of the temperature there. For the purpose of measuring this expansion and of
affording a visible indication thereof, I provide a glass circular index W' mounted
on pivots as shown in Fig. 17 and projecting into the axial opening through the
tubular hub Q as shown in Fig. 13. An opening q* is cut in the hub Q to permit
a part of the periphery of this index to play freely through it as shown in Fig. 15.
On the spindle upon which the index W is mounted, a small pinion w₁ is secured
which gears into a segment of a wheel on the end of a lever arm w; this pinion
has a flange on each side of the teeth, which flanges are slightly bevelled to afford
lateral support for the segment on the line of centres only, so as to avoid undue
friction, and the radius bars X X, Figs. 13 and 17, serve to maintain the teeth of
the pinion and segment wheel in proper relation with each other. One end of the
pyrometer band is attached to the lever arm w by a link w¹ at the pin joint of
the radius bars and the lever arm, as shown in Figs. 17 and 18, and by dotted lines
in Fig. 13, while the other end of the band is attached to the outer end of the
lever arm w by the two short links as shown in the same figures. As thus
arranged, when the ends of the pyrometer band approach each other, the lever
arm w will be moved so as to rotate the index W₁, and graduations upon its
circumference to degrees of temperature, will indicate the temperature. As the
index of each chuck is independent of the others, the readings of each, will give
the temperature at their respective locations within the piece, as it is heating and
when heated. When the pyrometer band V V is attached to the lever arm was
described above it is evident that some provision must be made to permit the band
to be compressed without turning the segment on the lever arm w so far, as to be
out of gear with the pinion on the spindle of the index W. For this purpose
the connection of the link w' to the end of the band V V is a yielding one and
The short lever which
can vibrate about the pin joint, Figs. 13 & 18.
vibrates about this pin joint provided with a foot which rests upon the band V
and is held against this band by the spiral spring y which is wound around a stem
that has its support at one end on the link v which vibrates about the pin joint a¹,
while the other slides through a support attached to the links by a pin joint
ata. The spring y is compressed between the head of the stem on the link v',
and the support between the links, and it must have stiffness sufficient to
maintain the connection in the position shown, so that the expansion of the
band V V may rotate the index W When the band V V is compressed to insert
or to remove the chuck as described, the lever arm w will be forced against the
pin Z in the end of the block which supports the radius bars X X, and as the arm
can then move no farther, the connection will yield the further distance required,
to enable the band V V to be compressed the amount required. To determine
whether the piece has been bent with the heat applied to expand it, I provide a

page_text: circular glass plate in the tube of the hub Q of the upper chuck, Fig. 3,
immediately under the incandescent light located on the upper side of this chuck,
as previously described; this glass plate has a small hole in its centre which may
have roughened edges to render its outline more distinct, while the middle chuck
is provided with a tube y" carrying fine cross wires about in the plane of the
chucking bars 99, and the lower chuck is provided with a telescope and cross
hairs, previously described, by means of which the alignment of the chucks and
consequently the straightness of the piece in which they are centered, can be
determined at sight. The telescope also enables the observer to read the
indexes Win each chuck, whereby the temperature at each chuck can also be
determined at sight.
When the jacket B is mounted upon the heating stand A' with the chucks
arranged within the jacket as shown in Fig. 3, the first operation will be to
adjust the lower chuck in line with the two upper ones, which latter will be at
right angles to the axis of the jacket, owing to their mode of suspension, the
upper chuck being drawn up to the under side of the supporting stand H so as to
just touch it, and all will become central as soon as the chucking bars 9 9 9 in
each chuck are forced outward by suspending a proper weight to the wire cord t
of each chuck.
The lower chuck rests upon the adjusting screws "n" and to adjust this chuck,
the electric current is turned upon the incandescent light on the upper chuck, to
illuminate the small circular opening under it, as also the cross hairs in the
middle chuck. The adjusting screws "n" are then manipulated, to bring the
cross hairs in the telescope in range with the circular opening, under the light in
the upper chuck, and when this is accomplished, if the bore through the jacket is
true, the cross hairs in the middle chuck should be in the same range. In case all
three chucks are not then in range, they must be released by raising or removing
the weight from the wire cord t t and readjusting the whole again until repeated
trials have shown, that the apparent error is caused by the crooked bore of the
jacket, and not by the adjustment of the chucks. If this error is not large,
allowance for it may be made by giving increased temperature to the jacket, so
that it will pass over the tube although it may not be absolutely straight. The
condition of the bore having thus been determined to be satisfactory, the burners
are then ignited in the small chambers, which surround the cavity of the heating
chamber D¹ D', when the products of combustion will pass up through the
heating chamber and escape at F. When the jacket is supposed to be
approaching the proper heat, observations should be made through the telescope,
to determine the temperature as shown by the glass index plates. When the
temperature of all parts of the jacket has thus been determined to be high enough,
and that the bore through it is straight enough, the telescope and chucks must be
removed, and the heating chamber with its contents be raised from the heating
stand, and transferred to a point over the tube upon which it is to be imposed,
which is mounted upon the assembling stand as seen in Fig. 5, but if the bore
through the jacket is not straight, the amount of error can be easily determined
before the chucks and telescope are removed, and if not too large, allowance can
be made for it by raising the jacket to a higher temperature. If the deflection of
the bore is too great, this fact can also be determined before an attempt is made to
assemble it upon the tube, and it should then be suffered to cool and be rebored.
The assembling stand 20 upon which the gun is mounted, is shown in Fig. 5. It
has a broad base to rest securely upon a horizontal foundation; it is provided
with a platform or flange 21, to support the heating chamber, the detachable base
of which 6' b', is shown as resting upon this platform.
The upper end of the stand 20 above the platform 21, is cylindrical and of a
diameter that will pass freely into the end of the jacket which supports the breech
plug, the interior is also cylindrical, of a diameter which will afford sufficient
thickness of metal between the interior and exterior diameters to support the gun

page_text: securely. The upper end of this cylindrical interior is partially closed by an
inwardly projecting flange 22, through the centre of which, the pipe 23 passes
freely, and around this pipe are openings through the flange 22, shown also in plan
in Fig. 6. The lower end of this cylindrical interior chamber, is closed by a cap 21,
which is provided with a long hub 25, projecting into the interior chamber. This
hub is bored to fit easily upon the pipe 23, which is here turned true. The cap 24
on its exterior and under side, is provided with a stuffing box 26 which is bored to
the same diameter as the long hub. The pipe 23 passes through the stuffing box 26,
the long hub 25 and the flange 22, which support it laterally, and projects above the
upper end of the stand 20, nearly the length of the gun tube 27, and is supported
vertically by the collar 28 firmly secured to it, and resting upon the upper end of
the long hub 25. Above the collar 28, the pipe 23 may be rough, and between
this collar and the flange 22 and upon the outside of the pipe 23, is a stiff spiral
spring which is partially compressed against the flange 22, by the hub 25 when the
cap 24 is bolted to its place, for which purpose the bolts which secure this cap to
the stand 20, are made longer than necessary for simply bolting the cap to place.
To the lower end of the pipe 23, a pipe 29 is attached, and upon this latter a valve
is mounted, to regulate the flow of fluid therein. In the side of stand 20 and above
the cap 24 and communicating with the cylindrical interior of the stand, is attached
another pipe 30 which is also provided with a valve to regulate the flow of fluid
therein. A reservoir of water or other cooling fluid is provided at such height
above the upper end of pipe 23, as will create a rapid flow through this pipe, when
the gun tube is in place as shown in the drawing, and when either pipe 29 or 30 is
connected to the reservoir, the valves on 29 and 30 are opened, one to permit the
entrance, the other the escape of the water. In lieu of this reservoir, other means
for creating such a flow may be employed, as for example, a pump.
The gun tube 27, is mounted upon the upper end of the stand 20 and between
its lower end and the stand, a packing is provided of any kind, that will secure the
joint between the two, against the escape of the cooling fluid. The upper end of
the pipe 23 is provided with a collar 31 firmly fastened to it, to which the
bolts 32-32 are secured, these bolts pass upwards through the cap 33, and screw
nuts upon their ends serve to clamp this cap against the upper end of the gun
tube 27. Between the cap 33 and the upper end of the gun tube 27 a packing
similar to that at the lower end of the tube is provided, to prevent the escape of
fluid between the cap and the upper end of the gun tube.
It will be observed that clamping the cap 33 against the top of the gun tube as
described, will tend to lift or lift the pipe 23, and compress the spiral spring between
the collar 28 and the flange 22; the space between the collar 31 on top of the
pipe 23 and the under side of the cap 33 must be such that at all times there will be
room for a free passage of cooling fluid through this space.
In the act of assembling, the heated jacket in its heating chamber, if provided
with a shoulder, is lowered over the muzzle of the tube, until the shoulder within
the jacket is in contact with the shoulder upon the tube, and the drawing represents
the jacket and the tube in this position, with the heating chamber lowered away
from the jacket and resting upon the flange 21. The gun tube in this case being
longer than the jacket B, and longer also than the heating chamber D' D', the
supporting stand H on top of the jacket B will be arrested by and will rest upon
the cap of the gun tube 33, as the jacket and the heating chamber are lowered, and
the cover plate jj will rest upon the top of the supporting stand H when the
lowering is continued, as shown in Fig. 5, so that when the jacket is in place on the
tube, the supporting stand H and the cover plate jj will be above the top of
the heating chamber D¹ D'. As the heated jacket descends over the cold tube, the
interior of the jacket is cooled by the tube, which without resistance, would
contract it, but it cannot contract until a sufficient thickness of the jacket has been
cooled to compress the exterior part of the jacket, the heat and dimensions of
which are maintained by the heating chamber which moves with it. Maintaining

page_text: the heat therefore, in the exterior of the jacket while the jacket is being lowered
over the cold tube, has the effect of maintaining the interior of the jacket at the
diameter it had assumed before assembling commenced, notwithstanding the cooling
to which the interior of the jacket is subjected during the assembling operation.
After the jacket B has been assembled upon the gun tube, the heating chamber D¹ D'
must be removed, for which purpose, the chamber must be slightly raised to relieve
its pressure upon the flanged ring piece bb' and then turned about its axis, until
the bayonet joint is clear, then the furnace plate with the heating chamber can be
raised, leaving the flanged ring piece 'b' and the annular plate a a¹, which form a
detachable base, resting upon the assembling stand 20, as in Fig. 5.
As the beating chamber is raised, it will pick up the cover plate jj and close the
opening in the top of the heating chamber, so that when the butterfly damper i is
closed, a current of air through the heating chamber will be prevented.
It is very desirable that the jacket B while shrinking, shall first seize the tube 27
at the shoulder on the tube, upon which the jacket is resting, when it is lowered to
its place on the tube, and that the lower end of the jacket shall seize the tube before
the upper end.
To effect this, the heating chamber is raised so that its bottom is slightly above
the shoulder on the tube, where it remains suspended, in order to retain the heat in
the upper end of the jacket. A spray of water is then directed against the
exterior of the jacket opposite the shoulder on the tube, which is then just below
the heating chamber, and a shield or wrapping may be secured around the jacket
below the jets, to guide the water off from the jacket, if this end of the jacket is
cooling too rapidly. After the jacket has been thus cooled so as to seize at the
desired point, a flow of water is established within the tube 27 to cool it and
consequently the jacket B from the interior. As the upper end of the jacket is
within the heating chamber which will impart heat from this end, the lower end
will cool most rapidly and seize before the upper end.
After the lower end has seized, the heating chamber D¹ D¹ is raised clear
of the tube, and the flow of water through the tube is continued until the
temperature of both tube and jacket is lowered to that of the atmosphere or
approximately so.
To impose the outer jacket upon the assembled jacket and tube, the muzzle
end of the tube must be placed upon the top of the assembling stand and
clamped thereon as before, with packing interposed between the tube and the
stand, and between the top of the tube and the cap 33, the outer jacket is
heated in the heating chamber D'D' or in this chamber shortened as described,
and when the proper temperature has been attained, it is imposed upon the long
jacket, by lowering it over the breech end in the same manner as this jacket was
imposed upon the tube by lowering it over the muzzle end, and its subsequent
treatment is the same.
As the outer jacket is so much shorter than the inner one, the proper amount of
expansion can be determined by the ordinary means of measurement, which can be
conveniently effected while it is in the heating chamber, and for the same reason,
the liability to deflection is so small, that it is unnecessary to provide such centering
chucks as those for the longer and smaller inner jacket.
The provisions hereinhefore recited for assuring proper conditions for assembling
the parts with certainty, should avoid all risk of premature seizure, but if notwith-
standing, any part should seize or should indicate seizure, before it has reached its
proper position, the apparatus herein before described affords the means for
separating such parts without injury, or for separating the parts of the gun after it
has been in service, so that a defective or an injured part can be removed and
replaced with a perfect one, and the gun be restored to its original value without
losing any part of it, except the defective part.
The principle which governs both the assembling and the disassembling of the
gun is the same, and it consists in producing a difference of temperature between

page_text: the parts which are to be assembled or disassembled, so as to alter their diameters
enough, to permit the outer one to slide over the inner one.
This cannot be effected after the gun is assembled, by heating one part and
cooling the other at the same time, as in so doing no positive line of demarcation
between the hot and the cold parts can be established, when they are in such close
filled
contact as in an assembled gun. If the gun tube with its jacket in place
with cold water and this temperature is maintained or nearly so, by a flow of such
water through the tube, and heat is applied to the jacket, the heat would be carried
off from the jacket so fast, that it could not be heated to the temperature required
to separate the parts, therefore, the parts which are to be separated, must all be
heated at least to the temperature required for assembling the gun, before the
cooling fluid is admitted to the tube. When this temperature has been attained, a
flow of cooling fluid, preferably water, must be established through the tube to cool
it as rapidly as possible, by which means the tube will have its diameter reduced so
rapidly, that the jacket, which will lose but little heat, can be lifted off the tube.
The time during which this difference of temperature can be maintained, is ample
for removing the jacket, but if from any cause the parts should again seize before
they are entirely separated, the water must be withdrawn from the tube, all the
parts must be again heated, and the cooling operation must be renewed as before.
The separation of the outer from the inner jacket is to be effected in the same way,
the jackets must be heated at least to the temperature required for assembling
them, and the inner jacket must then be cooled as rapidly as possible, and the parts
must be separated before the outer jacket has time to contract.
As the separation of the parts of a gun which have been assembled, depends upon
establishing the requisite difference of temperature between the parts for a limited
time, the separation will be facilitated by providing means for establishing a flow
of cooling fluid, through the tube at a much lower temperature than that of water
at its normal temperature. When this cold fluid is employed, it is not necessary to
raise the temperature of the parts so high, before the cooling fluid is admitted.
While it may not be desirable to use such a cooling fluid in every case, yet there
may be occasions when it would be necessary, as for instance, when the parts had
slid on each other in assembling, with too little clearance, and thereby had
roughened the surfaces, or after a gun had been long in service, and the condition
of the surfaces was unknown, I contemplate therefore, using a refrigerating
apparatus, when it is required, to lower the temperature of the cooling fluid which
flows through the tube, below that of water which can be conveniently obtained for
this purpose. A refrigerating apparatus such as is now in common use for making
ice, or for cooling beer vaults, or a tank of suitable size filled with ice or with ice
and salt, would be suitable for this purpose.
To separate the parts of a gun after they have been assembled, as for example,
the two jackets from the tube, the flanged ring piece band base a' a' should be
mounted upon the assembling stand 20, Fig. 5, the parts to be separated, jackets
and tube, should then be mounted upon the assembling stand, the heating chamber
must then be lowered over the jackets and tube, and secured to the flanged ring
piece by means of the bayonet joint, and the cap 33 secured to collar 31; heat
must then be applied to the jackets until the temperature is raised throughout the
jackets and tube at least equal to that required for assembling them. The heating
chamber must now be raised until the base a' a' is in contact with the lower end of
the jacket B, and the index Z must be adjusted as hereinbefore described. When
the jackets and tube have acquired the proper temperature, a flow of cooling fluid
must be established through the tube to cool it as rapidly as possible. A strain
must then be exerted through the hoisting apparatus, and the heating chamber,
upon the lower end of the jackets, which will cause the index Z to move from the
perpendicular; when the jacket loses its hold upon the tube, the index will move
automatically toward the perpendicular and at the moment the jacket is loosened
upon the tube, the heating chamber and the jackets should be raised rapidly clear
of the tube.

page_text: Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that what I claim is :-
1. A built up breech loading gun for ordnance, formed of a tube in one piece,
through the axis of which is a hore to suit the diameter of the projectile to be used
therewith, and a jacket which envelops the tube for a length, not less than ten
times the diameter of the bore of the jacket at the breech end, said jacket being
shrunk upon the tube, substantially as and for the purpose set forth.
2. A built up breech loading gun for ordnance, formed of a tube in one piece,
through the axis of which is a bore to suit the diameter of the projectile to be used
therewith, and a jacket which envelops all of that portion of the tube which is
reinforced, which portion must not be less in length than ten times the diameter of
the bore of the jacket at the breech end, said jacket being shrunk upon the tube,
substantially as and for the purposes set forth.
3. A built up breech loading gun for ordnance, formed of a tube in one piece,
through the axis of which is a bore to suit the diameter of the projectile to be used
therewith, and a jacket of such length as to sustain the breech plug and to envelop
all the surface of the tube which is to be reinforced, which surface must not be less
in length, than ten times the diameter of the bore of the jacket at the breech end,
said jacket being shrunk upon the tube substantially as and for the purpose set
forth.
4. The improvement in the art of constructing a built up breech loading gun for
ordnance, which consists, in making a tube in one piece of the length required, with
a bore to suit the diameter of the projectile to be used therewith, and a jacket in
one piece to envelop such portion of the tube as it is required to reinforce, then
heating the jacket to the proper temperature, then imposing it upon the tube and
maintaining the heat in the exterior of the jacket while so imposing it, substantially
as and for the purpose set forth.
5. The combination of a portable heating chamber with the exterior parts of
a built up gun, to maintain the heat in the exterior parts during the assembling and
disassembling of the gun.
6. A portable heating chamber heated by vertical furnaces about its periphery,
the upper ends of which are arranged for combustion chambers and the lower ends
to receive the products of combustion and the air heated thereby, and provided
with passages to transmit them to the heating chamber.
7. A portable heating chamber heated by vertical furnaces about its periphery,
which are supplied with liquid fuel from an annular reservoir below the heating
chamber, in combination with a detachable base to the heating chamber securable
to the annular reservoir.
8. A water circulating stand arranged to receive the tube of a gun vertically
mounted thereon, in combination with a pipe by means of which the tube is bolted
to the supporting stand, and through which a circulation of water throughout the
interior of the tube can be effected.
9. A portable heating chamber in combination with a water circulating stand,
provided with water inlet and outlet for effecting circulation within the portable
heating chamber mounted thereon.
10. The art of separating the parts of a built up brecch loading gun, which
consists in heating all of the parts to the proper temperature, then causing a flow
of cooling fluid to one end of that one of the parts which has the smallest bore, and
throughout the length thereof that is covered by the part to be moved, and then
when the parts have separated, moving the heated part er parts in relation to
the cooled part, as required.
11. The art of separating the parts of a built up breech loading gun, which
consists in heating all of the parts to the proper temperature, then maintaining this
heat in the exterior parts, while cooling the interior part, by causing a flow of
cooling fluid throughout the length thereof that is covered by the part to be

page_text: moved, and when the parts have separated, moving the heated part or parts in
relation to the cooled part, as required.
Dated this 25th day of June 1895.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.