Year: 1889

page_text: Date of Application, 14th Sept., 1889-Accepted, 23rd Nov., 1889

page_text: "
25 is an end view from the right side of fig. 23.
"
26 is a section half along line I II, half along line III IV.
"
27 is a front view of the guide channel alone.
By my new method and with the new machine I can make tubes quite finished
ready for use and tubes half finished which require reheating and are then welded
complete and finished on a mandrel as usual.
A bar of iron or steel which, when of very great length, may be wound up in a
ring, is made white hot and is then pushed into the machine into the spiral groove cut
in the hollow cone surface surrounding the mandrel.
The pitch of this spiral groove or its angle of inclination being at first very steep
diminishes gradually towards the outlet until it is equal to the breadth of the bar
itself, when the spiral groove in the cone-surface will disappear or in other words the
windings following each other will be quite close to and touch each other and no
partition will be between them.
The bar of iron or steel pushed into the machine is forced to follow the groove in
the hollow cone by the action of the fluted conical rolling mandrel which fits closely
in the hollow cone.
From place to place guide rollers and pressure rollers are arranged which cause that
the bar remains in continuous contact with the rolling mandrel.
At the end of the machine the mandrel projecting out of it is made cylindrical and
of same diameter as the inside width of the tube to be made. Here I expose the tube
to the action of obliquely working rollers by which the welding is completed.
The speed of these oblique rollers must be so that the linear advance of the tube
caused by their rotation shall be equal to the linear advance given to the tube by the
conical mandrel; by no means they are allowed to be driven faster. They may go
slightly slower to cause a certain upsetting action upon the material by retarding the
advance in front of the tube.
Tubes of any size and length may be made by this way; the ends of the bars may
be welded together to receive any desired length and they may be wound up and
heated in rings.
The machine designed by me for the purpose consists of a solid block or body A
made in two pieces, the upper and lower one, both held firmly together by bolts and
keys in any suitable manner as shown by figs. 2-4, 11–15 and 17 & 18 in two
different manners.
In the center this block is bored out conically and in the cone surface is cut a spiral
groove B (fig. 1 & 5); near the end of the cone-(near its base)-the groove runs
out in a straight tangential direction towards the circumference of the block A to
form the entrance into the machine.
The pitch or inclination of the spiral B is, as was said above, very steep at the
beginning and it diminishes towards the point of the mandrel until the pitch is equal
to the width of the bar and here the grooves or rather the solid partition between two
following windings or threads, disappears (fig. 5 & 16) making but a recess in the
cone surface.
In that part of the machine is placed the nut T (fig. 9 & 10); this is made exchange-
able and of hardened steel; it is held in place by ears cast at each side of the same
and embedded in cavities provided for it in the upper and lower part of the block A.
Into the hollow cone of the block A is fitted the conical rolling mandrel C
(fig. 1, 7 & 8). This is the positively acting, movable and motion giving element of
the machine; it is turned at a very high speed and has a pulling or pushing effect
upon the heated bar between it and the block A in the groove B; and it ends in a small
cylinder where it projects out of the block; its thin end is made in a separate piece
and is exchangeable.
At the thick or base end the mandrel is coupled to a driving shaft D carried in
plummer blocks E and being provided with the driving pulley or a spur-wheel to
receive its rotary motion from any suitable shafting.
°

page_text: The exchangeable part of the mandrel is made of hardened steel because it is
exposed to the greatest wear and tear; according to the diameter of the tubes to be
made it is exchanged as well as the nut.
Outside of the block A the mandrel is made cylindrical (F) ending in a short cone
again; this little cylinder F is coupled to the other part by a universal or ball joint
so that it can be adjusted and move a little in any direction (fig. 8). When small
tubes are being made this ball coupling may be dispensed with and the cylinder F
may be made in one piece with the other part of the end of the mandrel.
With the apparatus so far described are combined the oblique acting rollers G G¹
which are adjustable and press upon the cylindrical mandrel. The shafts H H of the
rollers G, G are carried in standards I, I and II¹; they of course rotate in the same
direction. In place of this little oblique rolling mill rollers g g' with parallel axes of
usual design and turning in opposite directions may be used (fig. 17 & 18) when it is
intended to make half finished fabrics only.
In order to hold the movable end of the mandrel centrally, I use the pressure
rollers N N¹ (fig. 2, 4, 11, 12 & 13) mounted in the brackets L & L which are fixed
to the face of the lower part of the block A in such a manner that they can be adjusted
conveniently and pressed against the tube being formed.
The spindle of the upper entrance guide roller 0 (fig. 14, 15 & 19, 20) may be fitted
with a little spur wheel e being in gear with a wheel e¹ of the shaft D. By this
means the rollers act positively and push or draw the bar into the machine, not only
guiding it and the movement or speed of the bar does not depend and is not caused
exclusively by the action of the mandrel alone.
The figure 21 shows in section the shape of the bar which I prefer using in making
tubes according to my method and with my machine and fig. 22 shows how the
spiral lap welded joint is formed by using such a bar and that the half round
bead is allowed or caused to rise upon the adjoining edge and to enter into the
corresponding groove of this edge, thus making a perfect joint.
In order to aid the formation of this joint, I place into one or two of the pits
or holes of the block A, nearest the outlet side of it instead of the guide rollers Pt
the retarding or break bolts m. By their means the workman retards the advance
of the bar by pressing the bolt down upon it when it first passes that place and
so assists the part of the metal following to mount upon the preceding winding and
thus to form the perfect lap joint with the half round bead lying on or in the corre-
sponding groove of the other edge of the bar.
The downward pressure of the retarding bolts can be applied automatically and
continuously by the use of springs or an excentric-(indicated at the upper side of
fig. 2) or by screwing them down.
The working of the machine described is as follows: The oblique rollers G 'G' and
the pressure rollers N N₁ as well as the guide rollers P¹ having been properly adjusted,
the mandrel is made to rotate very fast and now the white hot bar is pushed into the
machine between the entrance guide-rollers into the groove B, as soon as it reaches the
circumference of the mandrel this will pull it into the machine and force it along the
spiral groove B, the guide rollers P¹ in the pits Q assisting the bar to keep in contact
with the mandrel. The guide rollers P¹ are carried in brackets S by the bolts P,
which are adjustable, to exert a smaller or greater pressure upon the bars passing below
hem. Between the rollers and the sides of the holes Q in the lower part of the
lock A sufficient space is left for the outlet of scales of iron formed, in order to
revent choking of the passage and stopping the advance of the bar.
The bar entering nearly in a straight line gradually, but in a short time, takes the
crew form changing its angle of inclination as it advances until both edges of the bar
ouch each other (fig. 16) and nearly at the end of the block A the break bolt m causes
he foremost winding to be retarded in advancing axially and the edge of the following
inding to mount upon the preceding one, thus forming the lap joint and when
oming out of the block A the bar already formns a regular tube requiring only the
ecessary pressure to be finished and this is done by the oblique rollers G G₁ as
escribed before.

page_text: A box containing welding powder may be placed above the outlet of the machine
from which a continuous stream of that material falls upon the heated bar thus
aiding the welding.
If it should happen, or if desirable, that the heat of the tube or rather the bar at
the outlet from the block A should not be sufficient to make a good welded joint or if
it is desired so, a half finished fabric may be turned out and this is then reheated and
welded in a separate operation by means of a mandrel as usual.
In the modified construction shown by figs. 23-27 1 use in place of the block A
with the conical boring and the groove B cut in it a guide channel b made of
U shaped wrought iron or cast. This guide channel I wind round the mandrel a ;
it forms an independent piece of the machine and is suitably fixed on brackets c° and
put together by means of flanges in pieces each forming one half turn. At the
entrance side it is enlarged like a trumpet in order to facilitate the entrance of the
hot bar of iron.
Towards the point of the conical mandrel-(towards the left in figs. 23 & 24)-the
channel b abuts against a block d which corresponds to part of the block A and
is also made in two parts; it contains the exchangeable nut which has the same
object as in the machine described before and is of exactly the same construction.
The mandrel a is made exactly as before and it is coupled to the shaft f, by means
of which it is turned at a high speed. At the left side of the mandrel where it
projects beyond the block d or the nut e respectively it is cylindrical and acted upon
by oblique rollers hh, or ordinary rollers may be used instead of the latter as before.
But instead of the guide rollers which were placed in the holes Q and which could
not be driven, I here use the rollers keyed on shafts R1, R2 etc. placed round
and along the mandrel. The shafts R1, R2, etc. are provided with pinions m³, m²
m³, m being in gear with the wheel n on shaft and they are carried in plummer
blocks o which can be pressed by springs or otherwise towards the mandrel. These
blocks or bearings are mounted on the bars p which again are fixed on the block d and
on the plummer block g°.
From the above and by means of the drawing it will be easily understood that this
machine works exactly like that described before, but the guide rollers act positively
and being driven themselves they drive or push the bar forwards which serves for
forming the tube; they are easily accessible and the channel, if necessary can be
inspected easily.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is :
1.) In a machine for making welded tubes with a spirally running lap joint the
combination of the block A having a spiral groove B in its hollow conical boring, the
holes or pits Q, the exchangeable nut T, the entrance rollers 00' and the guide and
pressure rollers P₁ with the rolling mandrel ().
2.) The combination of the block A having a spiral groove B in its conical
boring, the holes Q, the exchangeable nut T, the entrance rollers 00', the guide
and pressure rollers P₁, the rolling mandrel C, the exchangeable mandrel end C
and the cylindrical end F, being made adjustable by a ball joint, with the oblique
rollers G G¹, the pressure rollers N N' as set forth and specified.
3.) The combination of the block A having a spiral groove B in its conical
boring, the holes Q, the nut T, the mandrel & C₁ F, the entrance rollers O O¹,
the guide and pressure rollers P¹ with ordinary rollers 9 g¹ as set forth and
specified.
4.) The combination of the block A having a spiral groove in its hollow cone,
the holes Q, the exchangeable nut T the mandrel C C F with the shaft D, the geared
entrance rollers 0 0¹ and the guide rollers P with the break or retarding bolts m as
set forth and specified.
5.) The peculiar shape of the bar having a half round bead on one side and a
corresponding groove at the opposite side as set forth and for the purpose specified.

page_text: 6.) The combination of the mandrel a (fig. 23) with the spiral channel b and with
guide rolls being fixed on rotary shafts R R2 driven by pinions m¹, m² in gear with
wheel n on shaft, the shafts R1, R2 being carried in adjustable bearings e°.
7.) The combination of the mandrel a, the spiral channel b, the rotating guide and
pressure rollers and shafts R', R³ with the block d containing the nut eº, the whole as
set forth and for the purpose specified.
Dated this 4th day of Santember 1889
KARL J. MAYER,
Agent for Jul. Düstenhöfer.