A New or Improved Tool for Cutting Out Boiler Tubes.
Year: 1889

page_text: Date of Application, 30th July, 1889-Accepted, 31st Aug., 1889
COMPLETE SPECIFICATION.
A New or Improved Tool for Cutting Out Boiler Tubes.
I SAMUEL E. CONDON of 164 South Eighth Street in the City of Brooklyn,
County of Kings and State of New York, United States of America Engineer 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:
The purpose of this invention is to accomplish the removal of old or damaged tubes
or flues from the interior of a shell or other boiler, the said tubes or flues
having been expanded or otherwise secured at their ends to and within the
apertures made therefor in the tube sheets of a shell boiler or the headers of a
sectional tubular boiler as the case may be.
In practice, the ends of the tubes are detached from their fastening in the tube
sheet or its equivalent by first cutting longitudinal slits from within the expanded
or upset margins of the tube at several points about its circumference and sub-
sequently driving the several sections of the end thus split inwardly so as to part
the metal from the margins of the opening in which it fits the withdrawal of the
tube then being permitted.
This process has heretofore been accomplished by driving a cold chisel held at
an angle to the tube, and projected within its end. It is important that the incisions
should not extend entirely through the margins of the tube or so nearly through
as to indent or rupture the tube sheet whereas the surface in the aperture of the
latter must be left smooth to receive the tube to be substituted. In the manner of
practice above stated the operation requires great care and a considerable time
therefore to accomplish the work.
The object of my invention is to effect a saving of labour and to perform the
cutting of all the slits simultaneously and to a proper depth that will insure against
rupture of the tube sheet. To this end my invention consists of a special tool
adapted to be inserted within the end of a tube; having expansive grippers adapted
to seize upon the interior of the tube and consisting essentially of a series of rotary,
anti friction or other steel cutters capable of longitudinal reciprocation, provided with
actuating mechanism to effect said reciprocation and mechanism for effecting their
expansion into the sides of the tube simultaneously or between each reciprocation.
Referring to the accompanying drawing forming a part of this specification and
in which similar letters of reference indicate like parts,
Fig. 1 is a side view of the device showing the cutters projected to the inward
termination of the stroke.
Fig. 2 is an end view of Fig. 1.
Fig. 3 a partially sectioned view of Fig. 1 showing the cutters at the retired
termination of their stroke.
Fig. 4 a sectional elevation of Fig. 1.
Fig. 5 a detail view partly in section.
Figs. 6 and 7 detail views pertaining to Fig. 5.
Fig. 8 is an end view of Fig. 5.
Figs. 9 and 10 detail views of a modification of the cutters.
Fig. 11 an end view of a cut tube within the aperture of the tube sheet after
subjection to the cutting operation of the present device.
Fig. 12 is a sectional elevation of a modification of the device.
Fig. 13 a cross section of Fig. 12 on the line xx, Fig. 12 and,
Fig. 14 a detail view pertaining to Fig. 12.
actuated by the ratative sleeve B

page_text: C are the cutters actuated longitudinally by the lever D which is rotative upon
the reciprocating stock E. The stock E is provided with spiral grooves F and
the collar G of the lever D provided with corresponding spiral teeth H fitting
therein, whereby the rotation of the lever D will effect the longitudinal movement
of the stock E which is relatively stationary, but longitudinally movable within the
bearings or guides I and the sleeve W integral therewith sustained at a fixed
position from within the tube J by the grippers A mounted within said guides.
The collar G of the lever D is connected to the sleeve W by means of the interiorly
recessed sectional collar X which fits the adjacent flanges a of the said collar G
and sleeve W respectively and couples them together. The collar X thereby retains
the lever collar G and imparts longitudinal motion to the stock E by the relative
motion of said collar G. The collar X is separable and removable by its sectional
construction in halves as shown held upon the sleeve W by the screws b.
It is obvious that the spiral grooves F and teeth H may be reversed in location,
that is to say the grooves located in the collar G and the teeth or male ridges of
the spiral upon the stock E.
The cutters C are adjusted outwardly by the entrance between their bearing
blocks K of the conical end of the screw spindle L which latter is entered or retracted
through the stock E by its screw threads therein. Its extent of entrance is limited
according to the adjustment of the nut M thereon, the latter being fastened at its
point of adjustment by the jamb nut N. The screw spindle L is turned by a wrench
applied to its squared head or preferably by the insertion of a pin as 0 (conveniently
stored when out of use in the lever ) as indicated) into the holes P of the said
squared head. The extreme end of the screw spindle L has a bearing Q, in the extreme
end of the stock E to centre it accurately between the bearing blocks K of the
cutters C.
The cutters C have a V shaped cutting edge sufficiently deep to cut the required
maximum depth of incision and the bearing blocks K are set within the, radial slots
or mortises as shown which guide them in their outward or their receding movement.
The cutters have their bearing blocks K mounted upon the extremities of the
springs R fastened by the screws R¹ (Fig. 4) and the said springs tend to retire the
cutters as against the outward thrust of the tapered spindle L.
The sleeve W is sustained in a fixed position to the interior of the tube to be
operated upon by means of the grippers A expansive from its projecting guides I
which latter fit corresponding V shaped sliding grooves in the inner end of the stock E
as appears in Fig. 2. The stock E is thereby kept from turning out of place when
the cutters are reciprocated and the latter guided always in the same line of incision.
The grippers A are capable of sliding longitudinally on the incline of their wedge
shaped bearing surfaces upon the inclined surfacos I so that the retracting movement
of the sleeve B will cause their expansion. For this purpose the sleeve B is interiorly
recessed by a circumferential groove U which engages with the spurs V of the grippers
and by its rotation upon its screw thread Y upon the stationary sleeve W moves
inward or outward by the application of the hand to its exterior projecting arms Z.
The grippers A are dovetailed in their sliding grooves as shown in Fig. 2 whereby
they are retained from dropping outward when the tool is withdrawn from the tube.
The extension c of the sleeve B confines the sectional collar X so that the latter may
be held in place without the use of the screws & if desired.
The modification of the cutters shown in Figs. 9 and 10 consists of the substitution
of steel cutting blades (for the rotary cutters C. The cutting blades Care
prismatic in shape presenting a cutting point at e. They are similarly mounted
in the stock E to the rotary cutters by means of springs as K₁ shown in said Fig. 9
which likewise retain them against the tapered portion of the spindle L. The
cutters Cact in the direction of the arrow shown, the abutment from which they
draw being that of the sleeve W against the end of the tube.
It is manifest that the grippers and the cutters used may be substituted by different
sizes that is to say greater depths radially from the axis of the tool whereby the
same instrument may be adapted for tubes of various sizes.

page_text: The operation of my invention is as follows:-The screw spindle L being withdrawn
so as to retire the cutters, and the sleeve B being moved to retract the grippers, the
tool is inserted within a tube J (Figs. 4 and 11). The sleeve B is now screwed outward,
that is to say toward the operator and the grippers A thereby expand to seize the
tube from within and thus hold the sleeve stationary and firmly in place. The
cutters Care now expanded by inwardly screwing the spindle L and simultaneously
the lever D rotated (in the present instance to a half turn) to and fro to actuate the
cutters from a suitable point as that indicated in Fig. 4 to their outward limit of
stroke as that indicated in Fig. 3 repeatedly until the required depth of incision is
required. Fig. 11 illustrates the completed operation, the incisions being preferably
three in number.
It is obvious that any number of cutters may be thus employed in lieu of three but
the said number is found preferable in practice.
The cutter stock E may be operated by any other means than by the spiral
groove and lever collar G shown as engaging therewith by a rotative motion
as for instance the stock E may be directly reciprocated by hand said stock having
a suitable handle or lever on its outer end therefor. This feature is illustrated by
Figs. 12, 13 and 14 which show the device as applied to the header of a sectional
tubular boiler. The stock E is in this instance reciprocated by the lever D₁ ful-
crumed at D² in bearings or lugs A³ projected from the clamping nut A¹, which with
the clamping nut A substitutes for the expansive grippers A in the preceding
device. The cutters Care similarly carried in the stock E and the latter has pro-
jecting pins a' upon which the bifurcated arm 61 of the lever D'engages to reciprocate
the stock. The clamping nut A¹ has an externally threaded sleeve A' upon the inner
extremity of which the nut A² is screwed.
The device is introduced by first placing the nut A inside the header through the
hand hole opposite the tube which can be done owing to the shape of the said nut as
shown in Fig. 14 and the threaded sleeve of the nut A' is then screwed into it as the
tool is inserted. The nut A' is then screwed tight, clamping the flange of the hand-
hole between the two nuts and the cutters expanded against the interior of the tube
by the conical screw spindle L as before while reciprocated by the lever D¹.
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 1
claim is
1. A tool for cutting boiler tubes inserted in and secured to the tube to be cut,
baving an internal tool stock capable of reciprocation and provided with cutters
operating longitudinally against the interior surface of said tube.
2. A tool for cutting boiler tubes, consisting of a body bearing expansive grippers
to seize upon the interior of a tube, and a stock capable of reciprocation bearing
expanding cutters that operate in a direction parallel with the length of the tube.
3. In a tool for cutting boiler tubes the combination of a sleeve connected to
the interior of a tube a cutter stock capable of reciprocation within said sleeve and a
lever collar rotating upon ɛaid sleeve and engaging with said stock by means of
spiral teeth and grooves as described.
Dated this 30th day of July 1889.
HERBERT & Co.,
18, Buckingham Street, Strand, London, W.C., Agents to Applicant.