mprovements in and relating to the Manufacture of Ribbed Tubes.
Year: 1893

page_text: Date of Application, 23rd Aug., 1893
Complete Specification Left, 19th May, 1894-Accepted, 28th July, 1894
PROVISIONAL SPECIFICATION.
mprovements in and relating to the Manufacture of Ribbed Tubes.
We, A. and J. STEWART and CLYDESDALE LIMITED, Tube Manufacturers,
f 41 Oswald Street Glasgow, and JOHN WOTHERSPOOx Engineer, of
Gartsherrie Cottage, Coatbridge, Lanarkshire, do hereby declare the nature of
bur invention to be as follows:-
This invention has reference to, and comprises an improved mode of, and means
or construction, arrangement, and combination of mandrils, and appliances for the
manufacture of tubes for boilers, condensers, and the like, with internal
longitudinal ribs or projections; and whereby this will be effected in a more simple
and efficient manner than heretofore.
In the manufacture of longitudinal internal ribbed tubes, difficulty has
heretofore been experienced to get the ribs in the inside of the tube inserted in the
It has hitherto been
relative grooves in the mandril on which the weld is made.
the practice to put the mandril bar, and the mandril in their relative proper
position between the rolls through which the tube is passed to be welded while at
the proper heat, and inserting the end of the hot tube on to the mandril. This
method has been found quite effectual in manufacturing tubes, without ribs but
when the inside of the tube is furnished with ribs the mandril over which it passes
in the process of welding requires to be furnished with corresponding grooves.
Frequently, notwithstanding every precaution, the ribs have not been inserted in
the corresponding grooves in the mandril; thus causing delay and waste of
material.
By our improvements we form the rear end of the mandril with a hole or socket
of a filler or conoidal shape at its entrance and nearly parallel at its inner end to
fit on to a corresponding pin or projection in the centre of the advance end of the
mandril bar. The mandril is formed with the usual tapered point and is inserted
in the end of the tube to be welded while it is at rest before leaving the heating
furnace, the ribs in the tube taking their proper position in the grooves of the
mandril. The point of the mandril bar (which retains the mandril in the proper
position while the tube is passed through the rolls in the process of welding) we
also make of conical or taper shape to enter the recess in mandril. Or vice versa
the mandril may be formed with a solid tapered end, and the mandril bar be formed
with the conoidal socket. By this means the tube with the mandril in it is guided
into its relative proper position between the rolls. Or alternatively a short
conoidal guide may be fixed close up to, and in front of the welding rolls, and
guide the end of the tube and mandril between the rolls on to the end of the bar.
The mandril bar is or may be placed in the tube while the tube lies in the heating
furnace, the bar.being passed through the welding rolls for this purpose, and the
opposite end of the bar would be guided to its place by any convenient arrange-
ment of guide, and be pushed forward into the welding position of the rolls along
with the tube. Or by another alternative the mandril bar may be made telescopic
and its front end with the mandril be drawn out, and inserted in the tube while it
lies in the beating furnace as before described, and be then pushed forward to the
welding position on the fixed or stationary part of the mandril bar.
Dated 22nd Auœust. 1893
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.

page_text: Improvements in and relating to the Manufacture of Ribbed Tubes.
We A. & J. STEWART and CLYDESDALE LIMITED, Tube Manufacturers of
41 Oswald Street Glasgow, and JOHN WOTHERSPOON Engineer, of Gartsherrie
Cottage Coatbridge Lanarkshire do hereby declare the nature of our invention
and in what manner the same is to be performed, to be particularly described,
and ascertained in and by the following statement in writing that is to say :—
This invention has reference to and comprises an improved method and means
or construction, arrangement, and combination of mandrels and appliances for the
manufacture of tubes for boilers, condensers, and the like with internal longitudinal
ribs or projections; and whereby this will be effected in a more simple and
efficient manner than heretofore.
In the manufacture of longitudinal internal ribbed tubes, difficulty has hereto-
fore been experienced to get the ribs in the inside of the tube inserted in the
relative grooves in the mandrel on which the weld is made.
It has hitherto been the practice to put the mandrel bar and the mandrel in their
relative proper position between the rolls through which the tube is passed to be
welded while at the proper heat and insert the end of the hot tube on to the
mandrel.
This method has been found quite effectual in manufacturing tubes without ribs
but when the inside of the tube is furnished with ribs the mandrel over which it
passes in the process of welding requires to be furnished with corresponding
grooves.
Frequently notwithstanding every precaution, the ribs have not been inserted in
the corresponding grooves in the maudrel; thus causing delay and waste of
material.
And in order that our said invention and the manner of performing or carrying
the same into effect or practice may be properly understood we have hereto
appended an explanatory sheet of drawings in which
Figure represents an elevation broken away and partly in section showing
how our improvements may be carried into practice, the mandrel being shown as
inserted within a tube in the furnace, and the mandrel bar as guided between the
welding rolls.
Figure 2 is a detached sectional elevation of the improved mandrel and Figure 3
a corresponding view of the mandrel bar,
Figure 4 represents a sectional elevation of the welding rolls and conoidal guide.
While
Figure 5 shews a transverse section of part of a tube as formed with projecting
ribs.
Referring to these drawings:-
By our improvements we form the rear end of the mandrel a with a hole or
socket at of a filler or conoidal shape at its entrance a' and nearly parallel at its
inner part a and tapered at its end a to fit on to a corresponding pin or
projection in the centre of the advance end of the mandrel bar b.
The mandrel a is formed with the usual tapered point a' and is inserted in the
end of the tube B to be welded while it is at rest before leaving the heating
furnace A, as shown in Figure 1, the ribs B' in the tube B Figure 5 taking their
proper position in the grooves of the mandrel a. The point of the mandrel
bar b, (which retains the mandrel a in the proper position while the tube B is
passed between the rolls C C' in the process of welding) we also make a conoidal
or taper shape to enter the recess a in mandrel a. Or vice versa the mandrel a
may be formed with a solid tapered end and the mandrel bar & be formed with the
conoidal socket.

page_text: By this means the tube B with the mandrel a in it is guided into its relative
proper position between the rolls C C. Or alternatively as shown in Figure 4 a
short conoidal guide c may be fixed close up to, and in front of the welding
rolls C C and guide the end of the tube B and mandrel a between the rolls on the
end of the bar b.
The mandrel bar b is or may be placed in the tube B while the tube lies in the
heating furnace A the bar being passed through the welding rolls CC' for this
purpose and the opposite end of the bar b would be guided to its place by any
convenient arrangement of guide such as the forked upright D¹ carried on the
framing D and be pushed forward into the welding position of the rolls CC₁
along with the tube B. Or by another alternative the front end 6' of the mandrel
barb may be made to telescope or slide within and out from a hollow central
part 6 formed in the part b of bar and so be capable of being drawn out and
placed within the mandrel a while it lies in the heating furnace A, the part b
remaining stationary; and the part 6 would afterwards be pushed within the
hollow part to the position shown in full lines in Figure 3, when the tube B is
being pushed forward to the welding position so that the end at of mandrel
may come up against the end 6 of mandril bar b.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
:-
First. The method of manufacturing tubes having internal ribs consisting in
placing the mandril in position while the tube is at rest in the furnace and guiding
the mandril bar while it is drawn through the rolls and inserted in the mandril in
the tube within the heating furnace all for the purpose of placing the ribs of the
tube in the grooves of the mandrel with certainty and welding the ribbed
tubes substantially as herein described in reference to and by way of application
shown in the accompanying drawings.
Second. In the manufacture of ribbed tubes the forming of the mandrel with a
filler or conoidal shaped hollow entrance end and the forming of the mandrel bar
with a solid conoidal or narrow end, or vice versa, substantially as and for the
purposes herein described in reference to and by way of application shown in the
accompanying drawings.
Third. In the manufacture of ribbed tubes, the forming of the, mandrel bar
with a telescopic or sliding narrow end, substantially as and for the purposes
herein described.
Fourth. In the manufacture of ribbed tubes, the fitting and use of a filler shaped
or conoidal hollow guide close up to and in front of the welding rolls, substantially
as and for the purposes herein described in reference to and shown in the
accompanying drawings.
Dated the 18th May 1894.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.