IMPROVEMENTS IN ROLLING-TRAINS
Year: 1885

page_text: I, FREDERICK JOHN BROUGHAM, of 46 Lincoln's Inn Fields, in the County, of
Middlesex, Managing Clerk, do hereby declare the nature of said invention for
"IMPROVEMENTS IN ROLLING-TRAINS" (a communication to me from abroad by
Heinrich Bleckmann, Proprietor of the firm Joh. E. Bleckmann, Iron-works,
Mürzzuschlag, Styria, Austria,) to be as follows:-
As is known, breakages of the rolls in rolling-trains, which would otherwise
result from excessive strains, are usually prevented by interposing between the
bearings of the upper roller and the pressing-screws the so-called breaking-piece.
This breaking-piece being made of a known limited resistance, breaks first, as soon
as the strain exerted upon the rolls exceeds this resistance. The objections to this
arrangement are that, on account of the varying nature of the material of which
the breaking-pieces are made, it is very difficult to give them the required
resistance, and that moreover, after every accident, the breaking-piece needs to be
replaced.
According to this invention, very strong springs are used instead of the breaking-
pieces, said springs being so constructed that they do not yield under the ordinary
strain, but only do so when the strain is increased. These springs are by preference
made in the form of flat steel cups or chased steel discs and after their resistance
has been ascertained they are superposed upon the caps of the bearings to the
number answering to the desired total resistance. To hold them in position, they
may be provided with a central hole through which passes a guiding bar fixed to
the cap of the bearing, or this latter may carry an open casing or cup into which
the disc-shaped springs are loosely inserted. In every case, a strong cover, upon
which the pressing screw acts, is placed on the top of the pile. When the guiding
bar is used, the cover has a central hole and the pressing-screw is bored to receive
the top end of the bar.

page_text: COMPLETE SPECIFICATION.
Improvements in Rolling Trains.
I, FREDERICK JOHN BROUGHAM, of N° 46 Lincolns Inn Fields in the county of
Middlesex, Managing Clerk, do hereby declare the nature of this invention (a com-
munication to me from abroad by Heinrich Bleckmann, Iron-works, Murzzuschlag,
Styria, Austria,) and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-.
As is known, breakages of the rolls in rolling-trains which would otherwise
result from excessive strains, are usually prevented by interposing between the
caps of the bearings of the upper roll and the pressing screws the so-called breaking-
piece. This breaking-piece is constructed of cast-iron and is made of a known
limited resistance, so as to break first as soon as the strain exerted upon 'the roll
exceeds this resistance.
The objections to this arrangement are, on the one hand, that as soon as a
breaking-piece is broken, it no longer does its office but needs to be replaced by a
new one, on the other hand, that it is scarcely possible to construct these pieces
so exactly that they break just at the moment when the roll is too strongly
strained, while they resist the normal strain exerted by the metal under work.
These drawbacks are overcome by the construction of the housing-posts in the
manner hereinafter described with reference to the annexed sheet of drawings.
In the drawings, Fig. 1. is a side-view and Fig. 2. an edge-view of a housing-post
constructed according to the invention, viz, provided with an elastic safety-piece.
Figs. 3. and 4. show to larger scales two forms of the elastic safety-piece.
Circular disks a Fig. 3. made of spring-steel and having a diameter of from 4
to 8 inches and a thickness of 1 inch at most (by preference of from 'to of an
inch) are bored at their centres and then they are struck or cupped into the shape
of flat conical cups, the depth of which is in a certain ratio to the diameter;
instance, a disk having a diameter of 7 inches will be cupped to the depth of about
half an inch. The cupped disks are ground on both surfaces so as to exactly fit
one into another.
for
Afterwards these disks are tempered in the well known manner, and finally they
are, separately or by groups, repeatedly flattened by means of a powerful press
until they no longer yield under the pressure of this press. As soon as the disks
have been prepared in the above described way, it is ascertained by obvious
practical trials in the housing-post, what number of these disks will be necessary
for forming of them a safety-piece which only yields under the action of an
extraordinary surplus strain.
As, in spite of most careful working, it is exceedingly difficult to temper the disks
so uniformly as to give to all of them the same depth by flattening, it is necessary
to form the base of the pile of disks by the shallowest one and to superpose the
other disks in the order of their increasing depth. In consequence of such an
arrangement the edge at least of each disk will fully touch the disk undeneath.

page_text: In order to do away with the hollow spaces in the pile or column of disks, the
said pile is submitted to a sufficiently strong pressure-by preference produced by
means of a hydraulic power-and then it is screwed together, when it may be
looked at as one compact body.
The screwing together of the disks is effected by threading them upon a bolt b,
which exactly fits their holes, and which is provided with a shoulder 62 upon
which abuts the undermost disk; the upper end 61 of the bolt 6 is provided with
very strong screw-threads, upon which a large cylindrical nut c having about the
same diameter as the disks a is screwed. To prevent this screw nut from accidental
loosening, it may be secured by one or the other of the means usual for this
purpose.
In this manner, a safety-piece A. Fig. 1. is formed, which will not yield under
the enormous pressure necessary for rolling metals, but which will do so as soon as
the strain exerted upon the rolls surpasses the necessary pressure, as is the case when
a foreign body is introduced between the rolls B. and B¹, or when the metal to be
rolled is too thick or too cold; in this case the safety-piece A. will sufficiently
shorten to remove any danger of breakage of a roll, as then the upper roll B, the
journals of which rest between the housings C. and C, is free to lift a small
amount.
When thin sheet-metal is to be rolled out, the yielding of the safety-piece by a
few thousandths of an inch would prevent the metal from being reduced to the
desired degree and consequently loosely superposed disks would never perform the
office in view. On the other hand, it is not possible to make use of one sole
thicker disk, as it could not be uniformly hardened throughout its whole thickness,
but would contain a soft and yielding inner portion.
In order to maintain the central portion of the disks under the set-screw D, and
above the middle portion of the cap C, and to prevent the said disks from being
turned by the said screw, the thickened bottom end 63 of the bolt 6 projects beyond
the undermost disk and is made prismatical, while the top end of the said bolt
overtops the cylindrical nut c in the shape of a pin b³. This pin 6³ projects into a
corresponding bore of the set-screw D, while in the cap C. a suitably shaped hole
is provided to receive the thickened prismatical bottom end b' of the bolt 6.
As the hardened disks a would press their edges into the softer cap C. and nut c,
flat steel disks a¹ and a³, which are hardened to the same degree as the disks a are
interposed between the said parts; moreover the sharp edge of the undermost
disk a may be turned off, and thus this disk may be made to rest upon a face
instead of resting upon a mere edge.
As it may be possible in certain cases that the screw-threads upon the top-
portion b of the bolt b. have not the necessary strength to resist shearing, the
disks a may be made up into one piece without hollow spaces by means of inter-
posed disks e Fig. 4. In this case the central holes of the disks a may be dispensed
with and said disks may be held in position by a steel tube & having a longitudinal
slot; however, it is preferable, in this case too, to provide the disks with central
holes, into which a guiding bolt penetrating a hole of the cap C. is to be inserted,
as otherwise the disks would be liable to come out of order.
When the above described safety-pieces are to be used with very long rolls
which yield when their middle portions are working, and which consequently soon
show small cracks, successively growing deeper and finally causing the breakage
of the roll without the interference of an accident, the said safety-pieces are to be
composed of such a number of disks that they yield a little while the rolling-train
is normally working. This yielding should answer to the elasticity of the roll, the
ends of which could then lift at the same time that the middle portion is about to
yield, whereby the bending of the roll would nearly be prevented.
It is obvious that rectangular or polygonal disks may be used instead of circular
ones, without departing from the nature of this invention.

page_text: 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:
In rolling-trains, the interposition between the set-screw and the cap of the
upper roll, of a number of flat conical disks made of hardened spring-steel, fitting
each other, and being so connected by suitable means as to act like one body,
substantially as shown and described and for the purpose set forth.
Dated this 2nd daw of Tune 1000