IMPROVEMENTS IN EXPANSION JOINTS OR FITTINGS FOR STEAM OR OTHER PIPES AND IN LATHE APPLIANCES APPLICABLE FOR MANUFACTURING THE SAME
Year: 1884

page_text: I, ALEXANDER MCDONALD BLACK FRASER of 77 Regent Road Liverpool in the
county of Lancaster, Engineer do hereby declare the nature of my said invention
for "IMPROVEMENTS IN EXPANSION JOINTS OR FITTINGS FOR STEAM OR OTHER
PIPES AND IN LATHE APPLIANCES APPLICABLE FOR MANUFACTURING THE SAME,"
to be as follows:-
In connection with marine engines especially, great annoyance loss and even
danger are frequently caused through the breakage or leakage of copper, brass and
other malleable metal pipes owing to strains caused by variable expansion and
contraction.
Now this invention is designed to overcome this evil by the construction of an
expansion joint. This I form of corrugated metal, the corrugations being transverse
to the diameter of the pipe. In my experiments on this idea two difficulties at
once occurred.
First, the making of such a corrugated pipe at all.
Second-the preventing the corrugations from decreasing the sectional area of
the pipe. I overcome the latter difficulty by forming my corrugated pipe of larger
diameter than the two lengths of pipe it is required to join and riveting it over the
ends of the said pipes "sweating" the brazing in between.
The former difficulty I have overcome by forming the pipe in ordinary
cylindrical manner-I then place it on a screw mandril with threads similar to
the corrugations to be made but spirally a screw preferably of one thread. This
screw mandril is fixed in the chuck or headstock of the lathe and rotates with it.
The cylindrical pipe is slid on over the screw mandril before the lathe is placed in
position. On the sliding carriage of the lathe I place a standard securely fixed.
Horizontally in each standard opposite the turning axis of the lathe I place a
sliding piece sliding in guides and adjustable and having a roller at the end which
bears against the cylindrical pipe in the mandril and keeps it steady. The slides
are fixed when the roller bears against the pipe.
Over the mandril, adjustable as regards height in slides in the standards, I place
a yoke. This also when in position can be screwed tight in place. Immediately

page_text: above the axis of the lathe and mandril I place a piece sliding vertically in a slide
in or on the yoke and capable of being adjusted so as to approach or recede from
the axis of the lathe and be screwed tight in any position. In bearings near the
end of this piece, I place a spindle, and on this a roller having a projecting ridge all
round its circumference fitting the hollow of the thread of the screw but allowing
for the thickness of metal of the pipe to be formed.
The roller is held firm from all movement but that round its own axis by the
cheeks of the sliding piece.
The mode of action is as follows:-The mandril with tube nicely fitting over it
is placed in the lathe, the two side rollers are now fixed to revolve firmly against
the tube. The top roller is pressed tight against the tube at one end of the part to
be corrugated and pressed down till it bulges the metal of the tube into the thread
of the screw. Its sliding carrying piece is now fixed.
I, ALEXANDER MCDONALD BLACK FRASER, of 77 Regent Road, Liverpool, in the
county of Lancaster, Engineer do hereby declare the nature of my said invention
for "IMPROVEMENTS IN EXPANSION JOINTS OR FITTINGS FOR STEAM OR Other
PIPES, AND IN LATHE APPLIANCES APPLICABLE FOR MANUFACTURING THE SAME,"
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
In connection with marine engines especially, great annoyance, loss, and even
danger are frequently caused, through the breakage or leakage of copper, brass, and
other malleable metal pipes owing to strains caused by variable. expansion and
contraction.
Now this invention is designed to overcome this evil by the construction of an
expansion joint. This I form of corrugated metal, the corrugations being transverse
to the diameter of the pipe. These corrugations may either be formed in rings
round the pipe, or spirally round it, following the path of a screw thread. The
corrugations enable the pipe to expand and contract and (to some extent when
required) bend and thus prevent dangerous tensile compressive or bending strains
from coming on the other portions of the pipe. In my experiments on this idea
two difficulties at once occurred.
First. The making of such a corrugated pipe at all.
Second, the preventing the corrugations from decreasing the sectional area of the
pipe. I overcome the latter difficulty by forming my corrugated pipe of larger
diameter than the two lengths of pipe it is required to join, and riveting it over
the ends of the said pipes, "sweating" the brazing in between.

page_text: drawings.
In these Figure 1 is a front elevation of lathe, with my invention fixed thereon.
Figure 2 end view of standard,
Figure 3 plan of same.
Figure 4, end view of pressing roller and links.
Figure 5, end view of standard partly in section.
Figure 6 plan, and Figure 7 sectional elevation of apparatus for putting on
pressure.
The tube to be corrugated is made in the ordinary cylindrical shape. It is then
placed upon the mandril A, having an external diameter nearly equal to the
internal diameter of the tube to be corrugated, but having a screw thread cut in it
to the shape it is desired the interior of the corrugations of the tube should be.
This mandril is fixed in the chuck and headstock of the lathe, as shown in Figure 1
and rotates with the chuck.
B is the ordinary sliding carriage of the lathe, C a standard securely fixed
thereon. Horizontally on each frame or side of the standard opposite the turning
axis of the lathe, I place a sliding piece D sliding in guides E, and adjustable and
having a roller F at the end which bears against the cylindrical pipe in the mandril,
and keeps it steady. The slides are fixed by set screws or other appliance, when
the roller bears against the pipe.
Although I prefer these sliding pieces to be horizontal and radial to the mandril,
they can be at any other angle provided the ridge roller hereafter described, and
the roller on the slides be placed so as to bear against the tube, at such circular
distance from each other on the tubes that the slide rollers shall firmly grasp the
tube, and prevent it bulging laterally, while being operated on by the roller L.
Vertically over the mandril, if the aforesaid sliding pieces are horizontal and
adjustable as regards height in slides in the standards I place a yoke G. This also
when in position can be screwed tight in place. Immediately above the axis of the
lathe and mandril I place a piece H, sliding vertically in a slide I in or on the
yoke G, and capable of being adjusted so as to approach or recede from the axis of
the lathe, and be screwed tight in any position. In bearings J near the end of this
piece, I place a spindle K, and on this a roller L having a projecting ridge M, all
round its circumference fitting the hollow of the thread of the screw, but allowing
for the thickness of metal of the pipe to be formed. The roller is held firm from
all movement but that round its own axis by the cheeks of the sliding piece. N is
a lever weighted in very light work, but held down by mechanisin, such as shown
in Figures 6 and 7, with heavy work. It is fulcrumed at N¹ and bears on the
slide H by being linked thereto at N³ through links N³ linked to pin N' passing
through said slides.
Referring to Figures 6 and 7. O is the joint linked to the end of lever N by
means of pin O₁; P vertical rod screwed into a stationary nut in standard Q.
Nut r is firmly fixed in place, and secured by its bottom flange and checknut r¹.
R is a hand wheel forming a nut on screw P and serving to screw it down, when
pressure is to be put on the die roller.
The mode of action is as follows; The mandril A with tube nicely fitting over
it is placed in the lathe; the two side rollers F F are now fixed to revolve firmly
against the tube. The top roller L is pressed by means of lever N tight against the
tube at one end of the part to be corrugated, and pressed down till it bulges the
metal of the tube into the thread of the screw. Its sliding carrying piece H is now
fixed by tightening screws, wedges, or otherwise. The lathe is now set in motion,
and the top roller L slowly travels forward in the screw thread. The standards and
yoke have a forward feed regulated to suit the pitch of the screw. The roller
consequently bulges the substance of the pipe down into the groove thread of the
mandril. If the material of the pipe be thick or not very pliable, the entire thread
cannot be bulged in at once, but the roller L has to be passed over it several times

page_text: with a deeper feed given to it each time till the thread is complete. The pipe is
now withdrawn from the mandril by a screw motion and another inserted.
Of course as the mandril has to fit the pipe, a separate mandril is required for
each size of pipe, and in most cases, a separate grooving roller or die is also
required. It will also be obvious that the mandril could be stationary, and the die
caused to revolve round it with a forward feed, but such an arrangement would in
practice be very undesirable.
.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
1st The improved expansion joint or fitting for steam or other pipes, which
consists in a pipe formed with circular or spiral transverse corrugations forming a
part of the length of piping, so as to allow for variable expansion and contraction,
substantially as described.
2nd The improvement in expansion joints or fittings for steam or other pipes,
which consists of a portion of the pipe, formed of enlarged diameter and having
corrugations, the smallest internal diameter of which shall be approximately equal
to that of the straight uncorrugated portion of the steam pipe to which it is joined
at each end, substantially as described.
.
3rd The improved lathe appliance, for corrugating tubes with transverse
corrugations, which consists in a mandril turned to the corrugated shape, that it
is desired the internal contour of the pipe shall take, a rolling die with device to
put pressure on same to press the material into the tube as the tube and mandril
rotate relatively to said die, and steadying devices to maintain the tube up to its
work, substantially as described.
AT
1004