Improvements in the Manufacture of Corrugated Tubes and in Apparatus therefor.
Year: 1888

page_text: Improvements in the Manufacture of Corrugated Tubes and in
Apparatus therefor.
I, CHARLES DENTON HOLMES of the Town and County of Kingston upon Hull
Engineer do hereby declare the nature of this invention to be as follows:-
According to this invention I form the corrugations by forging or pressing and for
this purpose I employ a pair of dies carried by two arms one on the inside and the
other on the outside of the tube one of which arms with its die is caused to approach
and recede from the other by a hydraulic press as in an ordinary hydraulic rivetting
or flanging machine. The tube is rotated about its axis through a small angle after
each pressure of the dies so as to form the corrugation all round.
The dies are concave and convex respectively and may be made to form one or more
of the corrugations at the same time. I prefer to employ two or more rams in the
hydraulic machines, to enable this to be done.
The process of manufacture is as follows:-
I first make the tube out of plain plates, these are afterwards rolled to the required
diameter, and the longitudinal joints welded. I then cause the tube to be heated, in a
furnace, composed of an outer iron casing made in halves, or segments, lined inside
with firebrick and having connections fitted for blast pipes, in order to uniformly heat
the tube in the positions where the corrugations are to be made.
When heated the tube is acted upon by the dies as above described.

page_text: Apparatus therefor.
I, CHARLES DENTON HOLMES of the Town and County of Kinston upon Hull
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 :-
According to this invention I form the corrugations by forging or pressing and for
this purpose I employ a pair of dies carried by two arms one on the inside and the
other on the outside of the tube one of which arms with its die is caused to approach
and recede from the other by a hydraulic press as in an ordinary hydraulic rivetting or
flanging machine. The tube is rotated about its axis through a small angle after each
pressure of the dies so as to form the corrugation all round.
The dies are concave and convex respectively and may be made to form one or more
of the corrugations at the same time. I prefer to employ two or more rams in the
hydraulic machines to enable this to be done.
The process of manufacture is as follows:-
I first make the tube out of plain plates, these are afterwards rolled to the required
diameter, and the longitudinal joints welded. I then cause the tube to be heated in a
furnace composed of an outer iron casing made in halves or segments lined inside with
firebrick and having connections fitted for blast pipes, in order to uniformly heat the
tube in the positions where the corrugations are to be made.
When heated the tube is acted upon by the dies as above described.
In order that my said invention may be fully understood and readily carried into
effect I will proceed to describe the drawings hereunto annexed.
Figure 1 is an elevation partly in section and Figure 2 is a plan of a machine
operating to produce corrugations on a tube suitable for the furnace or flue of a
boiler.
Figure 3 shows a modification which admits of two corrugations being simultaneously
produced.
Figure 4 is a side view and Figure 5 is an end view of the furnace employed in
heating the tube.
▸ shows
a and b are two strong arms like the arms of a rivetting machine; these arms are
firmly fixed and are tied together at their lower ends. Above this connection there is
room between the arms to receive the side of the tube to be corrugated.
the tube suspended from above by a chain so that it can be rotated between the
arms as the work progresses. d is a die rigidly fixed to one of the arms, its form
corresponds to that of the corrugation which it is desired to produce. e is another
die, the counterpart of the die d; it is capable of a short movement to and fro at

page_text: right angles to the arm which carries it. f is an hydraulic press mounted on the
arm; the press produces the movements of the die as water under pressure is
admitted to its cylinder or allowed to escape from it.
The press is supplied from an accumulator or other source and the admission of
the water to and its exit from the cylinder of the press is controlled by suitable valves.
The tube is heated in the furnace shown by the drawings which consists of a casing
lined with fire brick and loosely surrounding the tube. The casing opens readily to
let the tube in and out. Gas and air are introduced into the furnace by pipes
connected at the holes gg. By the gas burning within the furnace the tube is highly
and equally heated. In order better to distribute the heat the tube can be turned
whilst it is in the furnace. When sufficiently heated the tube is conveyed to the
machine and the corrugation is produced by a series of pinches between the dies the
tube being rotated slowly and step by step. When two corrugations are to be
simultaneously produced as indicated in Figure 3 the moveable die or dies are actuated
by two hydraulic presses fand f.
For the purposes of my invention I can adapt either vertical, horizontal, or diagonal
hydraulic rivetting or flanging machines (such as are usually found in boiler
making establishments) by adding suitable dies thereto in order to press the before
mentioned stiffening rings or corrugations into the shape required.
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 I
claim is :-
1. The production of corrugations upon tubes by means of a pair of dies carried by
two arms one inside and the other outside the tube which dies are caused to approach
and recede by an hydraulic press operating directly upon one of them whilst the tube
previously heated is rotated between the arms substantially as described.
2. Apparatus for the production of corrugations, upon tubes consisting of arms
adapted to receive the side of the tube between them and carrying convex and concave
dies and a hydraulic press or presses by which such dies can be caused to approach and
recede substantially as described.
3. Apparatus for the production of corrugated tubes substantially as described and
represented in the annexed drawings.
Dated this 12th day of November 1888.