Improvements in the Construction of Tubular Mains for Conveying Steam or other Gas or Fluid, and in Tools used in their Manufacture.
Year: 1891

page_text: Date of Application, 4th Feb., 1891-Accepted, 7th Mar., 1891
COMPLETE SPECIFICATION.
Improvements in the Construction of Tubular Mains for Conveying
Steam or other Gas or Fluid, and in Tools used in their
Manufacture.
I, SEBASTIAN ZIANI DE FERRANTI, of 120, Fellows Road, Hampstead,
in the County of Middlesex, Electrician, 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 :-
My improvements relate first to tubular mains such as are described in the
Specification of a former Patent granted to me No. 7276, in the year 1889. Each
length of these mains is composed of a number of small tubes secured at each end
to a tube plate or flange common to all.
In order the more securely to hold the ends of the tubes in the holes formed
through the tube plates or flanges the holes may be made tapering, the larger
diameter being next to the tube end, the tubes being then expanded to the full size
of the hole, by a tubé expander, as shown in Figure A.
If desired as an additional security, a taper metal ring may be forced, or screwed
into the inside of a tube thus expanded, being held firmly in place by friction; by
a metal plate at the back, or by beading or turning the tube end over the metal
ring, as shown in Figure B, or by other methods. Preferably however, I form a
groove, or a number of parallel grooves all around the sides of each hole in the
tube plate or flange, and when the end of a tube has been inserted into a hole, I
first expand it with an ordinary tube expander, so that it shall fit tightly into the
hole as heretofore, and then further by a second tool, expand or roll the metal of
the tube, into the groove or grooves formed around the tube plate as shown in
the Figure C.
To do this I form the rollers of an ordinary tube expander with projections
around their circumferences, corresponding in position with the grooves around the
holes in the tube plate and thus form a corrugation or corrugations around the tube
to fit the grooves formed around the hole.
Thus diameter copper tubes " thick thus corrugated into a tube plate 21"
thick have withstood pressures up to nearly two tons per square inch before leaving
the tube plate. Preferably one groove only is formed and completed at a time as
by this means the metal of the tube is better able to flow into the grooves without
becoming thinned or stretched.
Another method is to form a corrugation or bead in the tube, outside the tube
plate but immediately adjacent to its two sides as shown in Figure D. Figures E,
F, G, show other methods of fixing the tubes with locking screws. Another
method is, for the corrugation to take the form of a fairly quick pitch thread, aud
another method is to screw the tube with a fine thread, into the tube plate adding
if desired one or more circular corrugations, as shown in Figures C, E, F, or beads,
as shown in Figure D, to lock the tubes in place. A combination of any of the
above methods may be employed.
For branch pipes or where only a single tube is required, it may be secureil
to its flange in any of the above methods, or combinations or modifications thereof.
Similarly for joining together lengths of tubular mains each composed of a single
tube 1 form the ends of the tubes either to enter one into the other as shown in
Figures K and L or into a short sleeve as shown in Figure H or onto a short
sleeve and then secure them together by forming transverse corrugations around
the tubes where they fit one into the other or into the tubular sleeve.
To prevent thinning or drawing the metal of the outer tube or sleeve, I prefer to
form a set of corrugations around the inner tube, before entering it into the outer
го

page_text: tube or sleeve, the corrugations around the outer tube or sleeve being then formed
to embed or fit into those already made in the inner tube.
The corrugations around the outer tube may readily be made to coincide with
those around the inner tube by the assistance of a mark on the inner tube or a
clamp embracing it from which the positions of the corrugations can be measured off.
Instead of forming a number of separate transverse corrugations, as shown in
Figures HK L, the corrugations may take the form of a fairly quick pitch thread
or one pipe may be screwed with a fine thread inside the other, or both pipes may
be screwed into or onto a short sleeve or centre piece and in either case if desired
one or more plain transverse or spiral corrugations rubbings or beading applied
externally or internally may be employed for locking the tubes together.
The corrugating is done with a tool similar to that used for cutting pipes to
shorten their length but with the circumference of the narrow steel wheel which is
forced against the exterior of the tube that is being acted on, formed with a
rounded circumference instead of with a sharp cutting edge as shown in Figure M.
It is evident that tools other than those above described can be employed for the
above processes.
Thus the tubes and tube plates may be rotated in a hollow spindle lathe and
expanded, beaded, corrugated or rubbed, both internally and externally by means of
a fixed tool such as a burnisher, or a wheel of suitable shape rotating on a fixed
holder, and conversely the tube may be held stationary and the tools rotated, or
rotated for a portion of a revolution, in any suitable machine.
N is a plan view of one form of multiple tube plate forming part of a tubular
main.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
1. In tubular mains for conveying steam or other gas or fluid and consisting of
a number of tubes fixed into one tube plate or flange common to all, the improved
methods of fixing the tubes into the multiple tube plate or flange common to all,
by expanding taper or straight, screwing, corrugating, rubbing or beading, by
taper rings or screws or lock nuts or by any combinations of the above substantially
as described and illustrated by Figures A-G.
2. In tubular mains for conveying steam or other gas or fluid and consisting of
a number of tubes fixed into one tube plate or flange common to all, the use of
one or more supplementary rubbings, beadings, corrugations or indentations either
inside or outside the multiple tube plate or flange, for additionally securing the
tubes in position substantially as described and illustrated by Figures CDE F.
3. In tubular mains for conveying steam or other gas or fluid and consisting
of a single tube fixed into a flange provided with bolt connections for coupling to
a second flange, and for making a continuous run of pipes, the improved methods
for fixing the tube into the Hange by expanding taper or straight, screwing,
corrugating, rubbing or heading, by taper rings, or screws, or lock nuts or by any
combinations of the above substantially as described and illustrated by
Figures A-G.
4. In tubular mains for conveying steam or other gas or fluid and consisting of
a single tube fixed into a flauge the use of one or more supplementary rubbings
beadings corrugations or indentations either inside or outside the flange for
additionally securing the tube in position substantially. as described and
illustrated by Figures C D E F.
5. In tubular mains for conveying steam or other gas or fluid the improved
method of jointing together two tubes by expanding or reducing one or both ends
of the tubes, fitting or screwing one tube over the other or both tubes over or
into a short sleeve piece and securing them in place by one or more transverse or
spiral corrugations rubbings and beadings applied externally or internally
substantially as described and illustrated.

page_text: 6. In tubular mains for conveying steam or other gas or fluid the improved
method of preparing the end of the internal tube by forming transverse or spiral
corrugations beadings or rubbings around it previous to entering it into the
external tube or sleeve piece and conversely of preparing the sleeve piece as above
previous to entering it into the tubes.
7. Forming the rollers of a tube expander with projections around their circum-
ferences substantially as and for the purpose described.
8. Forming the wheels or tools of a pipe cutter with rounder circumferences
substantially as and for the purpose described.
this 4th day of Wahmury 1801
CARPMAEL & Co.,
Agents for the Applicant.