A TUBE EXPANDER
Year: 1884

page_text: We ROBERT BARNARD and EDWIN MILES at the Office for Patents 323 High
Holborn in the County of Middlesex, Engineers do hereby declare the nature of
the said Invention for "A TUBE EXPANDER" to be as follows:-
=
A drift or mandrel having an enlarged tapered head has a screw (of rather
coarse pitch and double thread if desired) free to turn upon it in a cylindrical box
or nut the mandrel being plain. In the inner end of the box are rollers preferably
three in number free to turn in recesses in the box and capable of projecting
beyond the box.
A spanner or lever is placed upon the outer portion of the nut and hangs loose
upon it but when it is desired to put the pressure on it is moved onto a portion
which is hexagonal or squared or otherwise adapted to it so that it then has a
grip upon the screw. It is kept in position by a ring which also acts upon a
collar upon the mandrell and so holds both in place. An ordinary ratchet brace
handle serves to turn the drift.
For bell-mouthing the tubes a tapered collar-removable or adjustable-can be
fitted upon the outside of the box, so that as it revolves it presses out the end of
the tube. As there is a good leverage the expander can be worked about for this
purpose and the corners of the rollers may be rounded to facilitate this. The same
end may be attained by making the rollers longer and with a double cone the
outer one serving to bend out the tube instead of the collar. In practice the
expander is inserted into the mouth of the tube and the drift screwed in by means
of the nut until the rollers are sufficiently expanded to act upon the tube. The
drift is then revolved by the handle and extra pressure applied as required.
The object in bell-mouthing the tubes is to make every tube act as a stay
while dispensing with the necessity for beading the tubes as now commonly done.
By changing the box this expander will serve for several different sizes of tubes.
1004

page_text: We ROBERT BARNARD and EDWIN MILES at the Office for Patents, 323 High
Holborn in the County of Middlesex Engineers do hereby declare the nature of
this Invention for "A TUBE EXPANDER" and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
A drift or mandrel having an enlarged tapered head has a screw of rather
In the
coarse pitch (if desired) free to turn upon it in a cylindrical box or nut.
inner end of the box are rollers preferably three in number free to turn in recesses
in the box and capable of projecting beyond the box.
A. spanner or lever is placed upon the outer portion of the nut and hangs loose
upon it but when it is desired to put the pressure on it is moved on to a portion,
which is hexagonal or squared or otherwise adapted to it so that it then has a
grip upon the screw.
It is kept in position by a ring which also acts upon a collar upon the mandrel
and so holds both in place. An ordinary ratchet-brace handle serves to turn
the drift.
For bell mouthing the tubes a tapered collar, removable or adjustable, can be
fitted upon the outside of the box so that as it revolves it presses out the end of
the tube. As there is a good leverage the expander can be worked about for this
The same
purpose and the corners of the rollers may be rounded- to facilitate this.
end may be attained by making the rollers longer and with a double cone the
outer one serving to bend out the tube instead of the collar.
In practice the expander is inserted into the mouth of the tube and the drift
screwed in until the rollers are sufficiently expanded to act upon the tube. The
drift is then revolved by the handle and extra pressure applied as required.
The object in bell mouthing the tubes is to make every tube act as a stay
while dispensing with the necessity for beading the tubes as now commonly done.
By changing the box this expander will serve for several different sizes of tubes.
In the accompanying Drawings Figure 1. is a sectional elevation of the tool.
Figure 2. a plan upon line 3. z Figure 1. Figure 3 a section of a portion of the
tool with the collar for bell mouthing the tubes and Figure 4. a view of a roller
for expanding or shouldering the tube on both sides of the tube plate.
A is the box or nut B the screw and C the mandrel having the circular collar D
fixed to it by screws so that it can be readily removed and changed for the
hexagonal collar shewn in Figure 2.
The cap E is screwed by screws to the end of the screw B as shown the collar D
being free to turn in the recess E¹ but as the screw is moved in or out the
mandrel C is carried with it.
•
The projecting portion of the cap E is squared at E to receive the wrench or
spanner F; the most convenient form of this portion is hexagonal and I therefore
prefer to adopt that shape in this and the other places. The portion Es of the cap
is round for the spanner to rest on when not in use.
The end of the mandrel is also squared at C₁ to receive the ratchet brace G by
which it is revolved.
The nut A is squared at A¹ to receive the wrench or spanner H the round
portion A serving for it to hang on when not in use.
K is one of the rollers having a double taper somewhat as shown; the action is
as follows:
The tool being placed in the tube P the mandrel C is drawn out by the nut A
forcing out the rollers K against the tube.

page_text: Pressure is applied by turning the screw B by the wrench F and the mandrel C
by the brace G which is usually sufficient to revolve the rollers K and expand the
tube, the inner portion of the rollers K¹ expanding it against the tube plate Land
the outer portion K' forcing out the end of the tube which projects beyond the
tube plate and bell mouthing it as shown.
If the form of roller shown in Figure 4 be used the tube will be expanded or
have a shoulder formed on both sides of the tube plate which is thereby much
strengthened as will be well understood.
When on account of the roughness of the tube the tool sticks and more power is
required to turn it, the wrench H may be used upon the squared portion A¹ this
carries the whole tool round.
When the job is finished the pressure is relaxed and the tool withdrawn.
It will be seen that in the rollers K there is a shoulder K³ the object of this is to
set back the portion of the tube projecting beyond the tube plate and form a
shoulder P¹ somewhat as shown in Figure 1 so as to cause the tube to become a
stronger stay than it would be if the end of the tube were merely bent outwards.
The portion K' of the rollers is shown in Figure 1 as having a very slight taper,
but it must be understood that the exact shape of the rollers may be varied as
required, though it is desirable to make the taper of the portion K³ correspond to
that of the mandrel so that a large bearing surface may be obtained.
Referring to Figure 2 it will be noticed that the recess E¹ is squared (hexagonal)
and that the collar D is also hexagonal to fit the recess; while the collar D in
Figure 1 is round so as to turn free in the recess.-Either collar may be used but
if the hexagonal one be used it forms a practically rigid connection between the
mandrel C and the screw B so that, operating either the brace G or the wrench F
will have the effect of turning both screw and mandrel.-This is useful to save
time where a large number of similar tubes have to be expanded and where &
single revolution or thereabouts is sufficient to finish one end of a tube.
By unscrewing the nut B the mandrel can be withdrawn from the nut or box A
and the rollers K be changed and the mandrel replaced without the necessity for
taking the tool to pieces.
Figure 3 shows a modification.
In this case the roller K takes the position
of K Figure 1. the portion K' being dispensed with and its function performed by
the tapered ring or collar M which is secured to A by sunk screws as shown; this
collar can be changed for one of a different taper or thickness if desired. The
action of this tool is similar to that shown in Figure 1. but the direction of the
taper of the mandrel head is reversed as will be seen. The pressure in Figure 1
put on by withdrawing the screw B from the nut A; in Figure 3 the pressure is
put on by screwing in the screw B; for general purposes the former plan is
preferable.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is
1. The mandrel C tapered as shown in Figure 1. of the Drawings whereby the
rollers are forced outwards by drawing the tapered portion of the mandrel into
the box A and towards the operator substantially as set forth.
2. The double purpose roller K having one face K' for expanding the tube
within the hole in the tube plate and another face K³ for expanding or bell-
mouthing the end of the tube projecting beyond the tube plate substantially as set
forth and illustrated in Figure 1 of the accompanying Drawings.
3. The roller K having the shoulder K³ substantially as and for the purpose set
forth.
4. The screw B having the recess F1", squared" or provided with faces to receive
the correspondingly faced collar D whereby it is so connected with the mandrel C
that the two must turn together substantially as set forth.
5. The recess E¹ arranged to admit either the round or
substantially as and for the purpose set forth,
squared" collar D.

page_text: 6. The combination with the box A of the tapered ring M substantially as and
for the purpose 'set forth.
7. A tube expander so arranged as to set back or form a shoulder with the
projecting end of the tube which thereby acts as a stay.
8. A tapered drift C operated by a screw B, and in direct contact with the
rollers Ki
9. The combination with the box A of the spanner H whereby the whole tool
may be revolved substantially as and for the purpose specified.
Ca
1004
ROBERT BARNARD.
EDWIN MILES.