Improvements in Boiler Tubes and other Tubes and Shells, and in the Mode of and Means for the Manufacture of same.
Year: 1895

page_text: Date of Application, 29th Oct., 1895
Complete Specification Left, 27th Aug., 1896-Accepted, 3rd Oct., 1896
PROVISIONAL SPECIFICATION.
Improvements in Boiler Tubes and other Tubes and Shells, and in
the Mode of and Means for the Manufacture of same.
I PETER JENSEN of 77 Chancery Lane London Chartered Patent Agent
do hereby declare the nature of this invention a communication to me from abroad
by Rudolf Müller of Myrens Værksted, Christiania Norway Mechanical Engineer,
to be as follows:-
This invention relates to the manufacture of steam boiler fire tubes and other
tubes and shells and more especially to the manufacture of such tubes and shells
that are made from corrugated sheet steel.
The object of this invention is to procure a tube or a shell having practically no
longitudinal seam or seams and which is made out of one single piece of sheet
material. This new type of tube has one seam only, which exten 1s from one end
of the tube to the other, but in a helical line around the same. This seam may be
formed by radial flanges on both sides of the plate, said flanges being riveted,
bolted or welded together either directly or with an intermediate strip of plate
placed between the flanges, for the purpose of stiffening and strengthening the
same. The said flanges may also have other form and the strip of metal placed
between the same may have a special section and may for instance be given the
form of a U.
I may proceed in the following manner in order to manufacture these screw
tubes and screw shells. A piece of plate of a width of say 2 feet, and a length
according to the length of the tube to be made, is cut on both ends at an angle, so
that the length of the line of cutting will be the length of the circumference of the
tube. The plate is then heated and rolled in the usual way so that the desired
corrugations and side flanges are obtained. Then the sheet or plate is again heated
in the furnace in front of which is placed a drum or roller of a diameter, that
answers to the inner diameter of the tube to be manufactured. This drum is
rotatable by means of machine power and is placed on a carriage running on tracks,
that form an angle with the furnace, the angle being the sanie as the pitch of the
tube screw.
When the plate is hot, or the front end of the same is hot (the furnace
may probably not be long enough for heating the whole length of the plate, which
then extends through the furnace at its other end), it is drawn out and the point of
its angular end clamped to the end of the drum and the latter put in slow rotation.
During the first rotation of the drum more clamps are bolted to the edge of the
plate so that it is securely held to the drum. The rotation of the same is then
continued, and the carriage carrying the drum will thereby be forced forwards as
the plate is wound on the drum.
It is preferred to arrange between the furnace and the drum a set of pressure or
guide rollers which serve to guide and keep the plate straight; these rollers should
be made to fit the corrugations of the plate. The drum is preferably made in
sections with longitudinal seams, so that by suitable means the diameter of the
same may be lessened or enlarged. When the tube has cooled down on the drum,
the latter is lessened in diameter and the tube is taken off after removal of one of
its hearings. The helical seam may then be welded or the flanges otherwise
united.

page_text: The sheet or plate may be rolled so that there remains a space between the
flanges, and between the same may be secured a similarly rolled strip having the
form for instance of a U, and the inner diameter of this helix may be made much
less than the diameter of the tube whereby the fire gases will be compelled to
wholly or partly pass the tube in a screw line, thereby augmenting the length of
their way and the efficiency of the heating surface of the tube.
The details in construction and manner of manufacture may also be varied in
other ways.
The advantages of this kind of fire tubing is the cheapness in manufacture,
gained from a great saving in material because of the possibility of using very thin
steel plates, and from saving of handwork. The strength of these tubes is also
much greater than that of other tubes, because there are no longitudinal seams.
Dated this 29th day of October 1895.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.
Improvements in Boiler Tubes and other Tubes and Shells, and in
the Mode of and Means for the Manufacture of same.
1, PETER JENSEN, of 77 Chancery Lane London, Chartered Patent Agent,
do hereby declare the nature of this invention (a communication to me from
abroad by Rudolf Müller of Myrens Værksted, Christiania, Norway, Mechanical
Engineer) and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
This invention relates to the manufacture of steam boiler fire tubes and other
tubes and shells and more especially to the manufacture of such tubes and shells
that ere made from corrugated sheet steel.
The object of this invention is to procure a tube or a shell having practically no
longitudinal seam or scams and which is made out of ene single piece of sheet
material. This new type of tube has one seam only, which extends from one end
of the tube to the other, but in a helical line around the same. This seam may be
formed by radial flanges on both sides of the plate, said flanges being riveted,
bolted or welded together either directly or with an intermediate strip of plate
placed between the flanges, for the purpose of stiffening and strengthening the
same. The said flanges may also have other form and the strip of metal placed
between the same may have a special section and may for instance be given the
form of a .
In the drawing,
Fig. 1 illustrates a plan view of the machinery preferably used for making
these shells, Fig. 2 is an end view of the same.
Figs. 3 and 4 are cross section and longitudinal section respectively of a
construction of the roller drum.
and
Fig. 5 shews the finished shell.
Figs. 6 and 7 shew different forms for the flange connections between the plates,
Fig. 8 shews a modification of the construction of the tube.
I may proceed in the following manner in order to manufacture these screw
tubes and screw shells. A piece of plate of a width of say 2 feet, and a length
according to the length of the tube to be made, is cut on both ends at an angle, so
that the length of the line of cutting will be the length of the circumference of the
tube. The plate is then heated and rolled in the usual way so that the desired
corrugations and side flanges are obtained. Then the sheet or plate is again

page_text: heated in the furnace d Fig. 2 in front of which is placed a drum or roller a¹, a³
Fig. 3, of a diameter that answers to the inner diameter of the tube to be mana-
factured. Figs. 3 and 4 shew one suitable form of drum.
This drum is rotatable
by means of machine power and is placed on a carriage b running ou tracks / that
form an angle with the furnace, the angle being the same as the pitch of the tube
screw. On the carriage and between the tracks is mounted a shaft c having a
tooth wheel 9 that meshes with a wheel g' on the drum shaft bl. When the plate
is hot, or the front end of the same hot (the furnace may probably not be long
enough for heating the whole length of the plate, which then extends through the
furnace at its other end) it is drawn out and the point of its angular end clamped
to the end of the drum by means of clamps f and the drum put in slow rotation.
During the first rotation of the drum more clamps fare bolted to the edge of the
plate so that it is securely held to the drum. The rotation of the same is then
continued, and the carriage carrying the drum will thereby be forced forwards as
the plate is wound on the drum.
It is preferred to arrange between the furnace and the drum a set of pressure or
guide rollers and m Figs. 1 and 2, which serve to guide and keep the plate
straight; these rollers should be made to fit the corrugations of plate. The drum
is preferably made in sections with longitudinal seams, so that by suitable means
the diameter of the same may be lessened or enlarged. When the tube has cooled
down on the drum, the latter is lessened in diameter and the tube is taken off after
removal of one of its bearings. The helical seam may then be welded or the
flanges otherwise united.
The construction of the drum may as stated be as shewn in Figs. 3 and 4, the
drum consisting of an inner drum a¹ and an outer sectional drum a². These
sections are united with the inner drum by means of wedges h having dovetailed
working faces as shewn.
The sheet or plate may be rolled so that there remains a space between the
flanges, and between same may be secured a similarly rolled strip having the form
for instance of a U as shewn in Fig. 8 and the inner diameter of this helix may be
made much less than the diameter of the tube whereby the fire gases will be
compelled to wholly or partly pass the tube in a screw line, thereby augmenting
the length of their way and the efficiency of the heat surface of the tube.
The details in construction and manner of manufacture may also be varied in
other ways.
The advantages of this kind of fire tubing is the cheapness in manufacture,
gained from a great saving in material because of the possibility of using very thin
steel plates, and from saving of hand work. The strength of these tubes is also
much greater than that of other tubes, because there are no longitudinal seams.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. As a new article of manufacture a boiler tube or shell constructed out of a
single sheet of corrugated steel (or other metal) wound in a helical line and united
along the said line or seam.
2. As a new article of manufacture a boiler tube constructed out of a single
sheet of corrugated steel (or other metal) wound in a helical line and having
between its seam flanges inserted a similarly rolled strip of metal of the shape of
a U which strip has less diameter than the inner side of the tube, so that a tube is
formed in which the gases are compelled to pass in a screw line.
3. The method of manufacturing boiler tubes and shells from a single piece of
corrugated plate, which consists in heating a long corrugated plate, winding it
helically on a drum placed at an angle in front of the furnace, and welding or
otherwise fastening the adjoining flanges of the plate together.
4. A rolling apparatus for manufacturing boiler tubes and shells from a single

page_text: piece of corrugated plate consisting of a rotatable drum journalled in a carriage
that runs on a track at an angle in front of the furnace.
5. The construction of rolling apparatus substantially as shewn and described.
Dated this 27th day of August 1896.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.