AN IMPROVED TUBE STOPPER AND HANDLE COMBINED FOR MULTITUBULAR BOILERS
Year: 1876

page_text: LETTERS PATENT to John Rankine, of North Shields, in the County of Northum-
berland, Superintending Marine Engineer, for the Invention of "AN IMPROVED
TUBE STOPPER AND HANDLE COMBINED FOR MULTITUBULAR BOILERS."
PROVISIONAL SPECIFICATION left by the said John Rankine at the Office
of the Commissioners of Patents on the 19th May 1876.
JOHN RANKINE, of North Shields, in the County of Northumberland, Super-
intending Marine Engineer. "AN IMPROVED TUBE STOPPER AND HANDLE COMBINED
FOR MULTITUBULAR BOILERS."
The object of my Invention is to remedy the defect of a damaged tube in a multi-
tubular boiler.
Where the damaged part is of small extent I employ a plug formed of a short
piece of pipe, with a rigid collar or flange at one end of a less diameter than the
tube for which it is intended. The other end of the pipe has a screw cut thereon
for a loose collar and nut to work. A packing of india-rubber, asbestos, or other
suitable material surrounds the pipe between the fixed and loose collars, so that
when the aforesaid nut is slack the plug shall throughout its length have a less
diameter than the tube; but when the plug is placed in position by means of a
handle or key, and the nut thereby tightened up, the india-rubber, asbestos, or other
suitable material is made to assume a larger diameter, and effectually covers up the
damaged part. The key can now be withdrawn, allowing the smoke and heated
gases to pass through the pipe of the plug, thus rendering availing the sound portion
of the damaged tube.
When however the tube is damaged to a great extent, and consequently rendered
useless, I then use two solid plugs constructed on a similar principle to the fore-
going, but in this case the centre or core, which is surrounded with india-rubber,
asbestos, or other suitable material, is solid. By means of the before-mentioned key
one of the plugs is thrust to the far end of the damaged tube, and the nut tightened
up until the increased diameter of the flexible material effectually stops up that end
of the said tube. The key is then withdrawn and the other plug placed in the fore
end of the tube, and the nut screwed up, as in the last case. Both ends of the tube
being now plugged, no leakage can occur.
The key by which means the plugs are placed in their proper positions is so made as

page_text: to lock on to the nut of the plug (the nut being provided with lugs for that purpose)'
and being of the same length as the tube the plug can be placed at the required
distance along the tube, when by giving the key one or two turns in the direction
of the screw, the fixed and loose collars are brought closer together, increasing
thereby the diameter of the flexible portion of the plug, and fixing it in its place.
A contrary turn of the key unlocks it from the nut, and the key is withdrawn,
leaving the plug in position.
The use of the key dispenses with the provision of a long shaft or rod from plug
to plug, as is usually the case in tube stoppers.
The key is also used for withdrawing the plugs when required.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Rankine in the Great Seal Patent Office on the 16th November
1876.
JOHN RANKINE, of North Shields, in the County of Northumberland, Super-
intending Marine Engineer. "AN IMPROVED TUBE STOPPER AND HANDLE COMBINED
FOR MULTITUBULAR BOILERS."
The object of my Invention is to remedy the defect of a damaged tube in a multi-
tubular boiler.
Where the damaged part is of small extent I employ a plug formed of a short
piece of pipe with a flange or rigid collar at one end, and of a less diameter than the
tube for which the plug is intended. The other end of the pipe has a screw cut
thereon for a loose collar and nut to work. A packing of india-rubber, asbestos, or
other suitable material surrounds the pipe between the two collars, so that when
the said nut is slack the plug shall have throughout its length a less dinineter than
the tube for which it is intended, but when the plug is placed in position by means
of a handle or key suitably made, and the nut thereby tightened up, the india-
rubber, asbestos, or other suitable material is made to assume a larger diameter, and
effectually cover up the damaged part of the tube. The key can be afterwards dis-
engaged from the nut and withdrawn, leaving the plug firmly fixed in position. The
smoke and heated gases passing through the pipe of the plug renders available the
sound portion of the damaged tube.
When however the tube is damaged to such an extent as to be perfectly useless,
I then use two solid plugs constructed on a similar principle to the foregoing, except
that in this case the centre or core, which is surrounded with the elastic material,
is made solid. By means of the before-mentioned handle or key one of the two
plugs is thrust to the far end of the damaged tube, and the nut of the plug tightened
up by turning the key until the increasing diameter of the flexible material effectually
closes that end of the said tube. The key is then disengaged from the aforesaid nut
and withdrawn, and the second plug, which is similar to the first, placed in the fore
end of the tube. The nut of this plug being tightened up closes this end of the tube.
Both ends of the tube being now plugged, no leakage therefrom can occur.
The handle or key by which means the plugs are placed in their proper positions
is so made as to lock on to the nut of the plug (the nut being round and provided
with lugs for that purpose), and being of the same length as the tube, the plug when
only one is used can be placed at any required distance along the tube. By giving
the key one or two turns in the direction of the screw the loose collar is made to
travel towards the fixed collar, causing thereby the flexible portion of the plug to
assume an increasing diameter, which fixes the said plug in its position. A slight
turn of the key in a contrary direction disengages it from the nut. The key can
now be withdrawn, leaving the plug in the tube.
The employment of the handle or key dispenses with the provision of a long shaft
or rod from plug to plug, as is usually the case in tube stoppers.
The key is necessarily used to withdraw the plug or plugs when required.

page_text: I will now proceed to describe my Invention more fully by aid of the accom-
panying Drawing, reference being had to the letters and figures marked thereon.
Figures 1 and 3 shew a longitudinal section of the rear and fore end of a split
tube, which is supposed to be so extensively damaged as to be utterly useless; two
solid plugs are therefore used, one of which is shown in elevation (Figure 1), and
the other in section (Figure 3); Figure 2 is a cross section on line 1, 2, Figure 1.
Figure 4 is a longitudinal view of a hollow plug fixed in position over a flaw;
and Figure 5, a longitudinal section of the same before the nut is screwed up, as in
the last Figure; Figure 6 is a cross section on line 3, 4, (Figure 4,) showing the
round nut provided with lugs to engage with the key; and Figure 7 illustrates
the application of the handle or key used for placing and fastening the plugs in
position.
In Figures 1 and 3 A, A, are the two solid plugs, cach consisting of a, the solid
corc or screwed bolt, the head of which is made large, as shown, to act as a support
to the elastic material b; or where for the sake of convenience the head is small, a
inoveable washer may be used in addition to give the requisite bearing surface to
the said material; c is a loose washer, and d a round nut with lugs d*, d*, (see
Figure 2).
B, Figure 4, is a hollow plug fixed over a damaged part of the tube, and composed
of a piece of pipe a* having a screw cut on its outer circumference; c* is a fixed
collar at one extremity of the pipe, or it may be made, as shown in the Drawing
(Figure 5), with a female screw corresponding to the external screw on the said
pipe, by which means should the fore end of the pipe become fixed or jammed in
the socket of the key it will act as a nut, and approaching the other collar c²
increase the diameter of the elastic material 6*. When the rear collar is secured,
that end of the pipe should be provided with a pin or beaten out to an enlarged
diameter to prevent the screwed collar at any time working off. Figure 5 is a
longitudinal section of this plug before the nut is screwed up, with the elastic
material lying between the two collars. The diameter of this plug is now less
than the tube, but when the nut e is screwed up (as shown in Figure 4) the two
collars are made to approach, and the elastic material swelling out and covering the
aperture completely secures it from leaking.
The handle or key I use to place and secure the plugs in the required position is
shewn in Figure 7, H being the handle and S the socket. The socket is formed, as
shewn, to receive the nut d, Figure 1, or e, Figure 4, the lugs d*, d*, (sec Figures 2
and 6) entering or 1 shaped notches, by which means the nut is socurely held and
the plug thrust down or withdrawn from the tube. When the plug has reached its
proper position (which with the solid plug is the extreme end of the tube) the key
is given one or two turns in the direction of the thread of the screw, which imme-
diately causes the elastic material to swell out by drawing together the two collars.
This act secures the plug, and the key being no longer required it can be withdrawn
by disengaging the lugs d from the or I shaped notches. Before the plug is
placed in the tube it should be screwed up to within a little of the diameter of the
tube, so as to ensure sufficient friction between the tube and the clastic material,
and prevent the plug turning round with the motion of the handle.
Having now set forth the nature of iny Invention of "An Improved Tube Stopper
and Handle combined for Multitubular Boilers," and explained the manner of
carrying the same into effect, I wish it to be understood that under the above in
part recited Letters Patent I claim, the tools or apparatus above described for
stopping the ends of or temporarily repairing leaky or defective tubes.
In witness whereof, I, the said John Rankine, have hereunto set my hand and
seal, the Fourteenth day of November, in the year of our Lord One thousand
eight hundred and seventy-six.