IMPROVEMENTS IN THE MANUFACTURE OF CURVED METAL PIPES AND IN PROVISIONAL SPECIFICATION
Year: 1870

page_text: LETTERS PATENT to John Penn, junior, Engineer, of the Steam Engine
Works, Greenwich, in the County of Kent, and William Hounsell,
Coppersmith, also of the above-named Works, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF CURVED METAL PIPES AND IN
PROVISIONAL SPECIFICATION left by the said John Penn and William
Hounsell at the Office of the Commissioners of Patents, with their
Petition, on the 24th November 1870.
We, JOHN PENN, junior, Engineer, of the Steam Engine Works,
Greenwich, in the County of Kent, and WILLIAM HOUNSELL, Copper-
smith, also of the above-named Works, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF CURVED
METAL PIPES AND IN APPARATUS EMPLOYED THEREIN," to be as follows:-
This Invention has for its object improvements in the manufacture
of curved metal pipes. Curved pipes of copper or brass of large diameter
(say from eight inches and upwards) are commonly made in two parts,

page_text: each semicircular in section, and these parts are fitted the one to the
other and brazed together. Such parts have heretofore been raised and
planished with hammers, and this is a long and laborious operation.
We employ for this purpose three rollers, namely, a pair of rollers
one convex on the face, and the other concave corresponding in cur-
vature with the sectional form of the half pipe to be produced. The
position of one or both of these rollers is adjustable by means of their
bearings being traversed in slots. The third roller is behind this pair
and is so set that when a strip of metal to form a half bent pipe is passed
between the rollers of the pair it comes against the third roller, and
so the trough which the pair of rollers produces is bent to a regular
curve the radius of which depends on the position of the third roller in
relation to the rollers of the pair, and this position is adjustable, the
bearings of the third roller being capable of being traversed in slots in
the frame. The third roller is always on the outside of the curve of the
piece which it is forming, and is convex or concave on the face according
as the convex or concave side of the half pipe is to be on the outside of
the curve or bend, for it will be understood that two pieces, one of each
sort, are required to fit together and form a bent pipe. The other
rollers can also be changed to adapt the machine to make curved pipes
of different diameters. The pair of wheels are driven by screws and
worm wheels or by other powerful driving gear. The edges of the
metal strips are made true and parallel before they are brought to the
machine, and edge guides are provided to prevent the strip twisting
whilst it is being bent, or the two ends of the strip may be held and
controlled by nippers or other instruments during the bending operation.
Two half pipes similarly curved being thus prepared their edges are
bevelled and notched together and then brazed. The curves may be
made in continuation of straight lengths in the same piece of metal.
Additional rollers may be employed to aid in controlling the metal.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Penn and William Hounsell in the Great
Seal Patent Office on the 24th May 1871.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Penn and William Hounsell in the Great
Seal Patent Office on the 24th May 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we,
JOHN 3

page_text: County of Kent, and WILLIAM HOUNSELL, Coppersmith, also of the
above-named Works, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of November, in
the year of our Lord One thousand eight hundred and seventy, in the
thirty-fourth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto us, the said John Penn, junior, and William
Hounsell, Her special license that we, the said John Penn, junior, and
William Hounsell, our executors, administrators, and assigns, or such
others as we, the said John Penn, junior, and William Hounsell, our
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "Im-
PROVEMENTS IN THE MANUFACTURE OF CURVED METAL PIPES AND IN APPARATUS
EMPLOYED THEREIN," upon the condition (amongst others) that we, the
said John Penn, junior, and William Hounsell, our executors or admini-
strators, by an instrument in writing under our or their hands and seals,
or under the hand and seal of one of us or them, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Hounsell, on behalf of
myself and the said John Penn, junior, do hereby declare the nature
of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
-
This Invention has for its object improvements in the manufacture
of curved metal pipes and in apparatus employed therein. Curved
pipes of copper or brass of large diameter (say from eight inch and
upwards) are commonly made in two parts, each semicircular in section,
and these parts are fitted the one to the other and brazed together. Such
parts have heretofore been raised and planished with hammers, and this
is a long and laborious operation. We employ for this purpose three
rollers, namely, a pair of rollers, one convex on the face, and the other
concave corresponding in curvature with the sectional form of the half

page_text: pipe to be produced. The position of one or both of these rollers is
adjustable by means of their bearings being traversed in slots. The
third roller is behind this pair, and is so set that when a strip of metal
to form a half bent pipe is passed between the rollers of the pair it
comes against the third roller, and so the trough which the pair of
rollers produces is bent to a regular curve the radius of which depends
on the position of the third roller in relation to the rollers of the pair,
and this position is adjustable, the bearings of the third roller being
capable of being traversed in slots in the frame. The third roller is
always on the outside of the curve of the piece which it is forming, and
is convex or concave on the face according as the convex or concave
side of the half pipe is to be on the outside of the curve or bend,
for it will be understood that two pieces one of each sort are required to
fit together and form a bent pipe. The other rollers can also be changed
to adapt the machine to make curved pipes of different diameters. The
pair of wheels are driven by screws and worm wheels or by other
powerful driving gear. The edges of the metal strips are made true
and parallel before they are brought to the machine, and edge guides
are provided to prevent the strip twisting whilst it is being bent, or
the end or ends of the strip may be held and controlled by nippers or
other instruments during the bending operation. Two half pipes similarly
curved being thus prepared their edges are bevelled and notched together
and then brazed. The curves may be made in continuation of straight
lengths in the same piece of metal. Additional rollers may be employed
to aid in controlling the metal.
In order that our said Invention may be most fully understood and
readily carried into effect we will proceed to describe the Drawings

page_text: smiths call the "back," that is to say, the part which has the concave
of the half pipe on the inside of the curve or bend. In this case as will
be seen the lower roller e in the standard 6 is hollow on the face and the
upper roller is convex, they are of the same curvature excepting the
allowance which is made for the thickness of the strip of metal which is
passed between them. The third roller g is like the roller e. When
it is required to produce the other half or part of the bent pipe called
by the copper smiths the "saddle," and which has the concave of the
half pipe on the outside of the curve or bend, the rollers e and ƒ are
taken out and replaced with the convex roller f below and the concave
roller e above; the roller g is also taken out and a convex roller like the
roller is substituted. Thus for each size of bent pipe to be made the
machine is supplied with four rollers, two convex and two concave,
but three rollers only are in use at a time.
The rollers represented
in the Drawings are the largest for which the machine is adapted.
The machine is provided with several sets of rollers for pipes of
different sizes. The bearings of the lower roller in the standard 6 are
arranged to slide in guides on the standard and they rest on screws h
which can be moved vertically in their sockets in the frame by turning
the nuts i which form parts of worm wheels with which worms on the
axis k gear. A¹ is a hand wheel by which this axis is turned. In a similar
way the bearings of the roller g can be moved along guides in the
standard c by screws 7, nuts and worm wheels m, and an axis n with worms
and a hand wheel n¹ upon it. The rollers e and fare driven by worm
wheels e¹ and f¹ on their axes, they gear with worms o' and p¹ respectively
on vertical axes o and p. There are bevelled pinions o³ and p² on these
axes gearing with bevelled wheels on the axes q and r, which are driven at
suitably differing speeds by driving belts from the main axis 8. The driving
belts are arranged so that the concave roller may make a greater number
of rotations than the convex roller. In working the machine a suitable
strip of copper having been prepared and a centre line marked upon it,
it is clipped centrally at one end in a vice like clip which slides on the
horizontal guide t, it is then entered truly between the rollers e and f
to a centre line marked upon the rollers. These rollers are set so as to
commence the bending of the strip to a trough like form, but without
putting too heavy a strain on the metal. The passages of the metal
between the rollers are repeated (the rollers e and f being set closer
together) until the metal is bent suitably for a straight half pipe. The
roller is during this operation so placed that it supports the metal

page_text: I is
without bending it. The lines between which the bend is to be made
are now marked on the metal (if this has not previously been done)
and the part between these marks is passed to and fro through the
rollers by reversing the direction of rotation of the main driving shaft
by means of ordinary reversing gear, and simultaneously the roller
raised so as gradually to bend the metal until the desired curve is
attained. The "back" and "saddle" having been in this way produced
they are notched together and the edges of the metal bevelled in the
manner usual for joining these parts, they are then soldered together
by the ordinary operation of brazing, and the bent pipe is finished off 1
by hand labour.
Having thus described the nature of our said Invention, and the manner
of performing the same, we would have it understood that we claim, the
production of curved metal pipes by rolling by means of convex and
concave rollers corresponding curved troughs known as "saddles" and 1
"backs," and notching and soldering them together, substantially as
described.
We also claim the apparatus for the manufacture of curved metal
pipes, substantially as described.
In witness whereof, I, the said William Hounsell, have hereunto 2
set my hand and seal, this Twenty-third day of May, in the
year of our Lord One thousand eight hundred and seventy-
one.