Improvements in the Manufacture of Black Plates or Sheets.
Year: 1898

page_text: Date of Application, 25th May, 1898
Complete Specification Left, 17th Feb., 1899-Accepted, 25th Mar., 1899
[Communicated from abroad by WILLIAM HENRY DONNER, of Monesson, in the
County of Westmoreland, State of Pennsylvania, one of the United States of
America, Manufacturer.]
Improvements in the Manufacture of Black Plates or Sheets.
I, WILLIAM BURGELAND JOHNSON, of 4, Clayton Square, Liverpool, in the County
of Lancaster, Engineer, do hereby declare the nature of this invention to be as
follows:-
Heretofore in the manufacture of black plate or fine sheets, where two stands
of rolls have been employed, one for roughing and the other for finishing, a double
furnace has been employed, having two heated chambers, the operation being as
follows:
The tin plate bars are heated in one of these furnace chambers and then rolled
into plates upon the roughing train. The plate or plates are then placed in the
other heating chamber of the furnace and being brought to the proper temperature
are then rolled in the finishing train and doubled. They are then replaced in the
same chamber, and again heated and rolled in the finishing train and doubled into
fours. After the doubling and trimming of one of the fours the pack, which has
cooled considerably, is replaced in the same furnace chamber which contains the
other packs of doubles. After the doubles are all rolled into fours one pack is
taken out, rolled and doubled into eights, during which operation the pack again
cools, and is again put back into the same furnace with the remaining packs of
fours, this cool pack tending to cool and harden the other packs in the furnace.
The remaining packs of fours are similarly rolled successively into eights and
replaced in the same. furnace chamber and the packs of eights are then successively
taken out and rolled and finished. The placing of the cooled packs of fours in with
the doubles tends to harden and chill the doubles and render them unfit for rolling
and the cooled packs of eights have the same action upon the packs of fours. This
hardening of the packs being heated is overcome to some extent by raising the
temperature and making the heat more intense, but this action is objectionable as it
tends to scale the iron and to pit its surface. The heating of the packs demands
a high degree of skill as there are several packs in the same chamber at the same
time and each pack inserted must be placed so that it will not interfere with the
taking out of the other packs to be worked.
Moreover, in the prior system of operation the rolling of the sheets has been a
difficult operation on account of the alternate heating and cooling of the rolls.
When the iron was rolled in the roughing train the finishing train remained idle
and hence would cool and contract, and after the iron had been roughed, the rough-
ng mill would stand idle and contract and cool, and hence both sets of rolls would
ften break from the expansion and contraction consequent upon this alternate
eating and cooling.

page_text: Moreover, the cooling of the rolls changes their contour, so that it is extremely
difficult for the roller to obtain accurately rolled sheets. This is especially the case
in the finishing rolls which are turned in such a way that when they are heated
to a certain point their surfaces will be of the correct shape for rolling sheets: and
hence as the temperature falls while these rolls remain inactive, it will readily be 5
seen that the sheets cannot be properly rolled upon them after they have cooled
down.
Where a single stand of rolls was employed, upon which both the roughing and
finishing were carried out, this set of rolls would work in a more continous
manner, but as the roughing of the heavy bars causes the rolls to expand much
more than after reduction, the sheets could not be rolled uniformly as the rolls
were constantly changing in shape or contour.
My invention overcomes these difficulties and it consists in roughing in one mill
and then passing the metal packs in a regular or continous manner through a
finishing mill or mills so that the finishing rolls will be continously maintained
at about the same temperature. These rolls can therefore be turned so that they
will be of the proper shape at this temperature and can be kept substantially of
this shape. It also consists in passing the metal continously or regularly through
the roughing rolls, thus maintaining these rolls continously at the same tem-
perature, as well as in passing the metal simultaneously and regularly or
continously through both the roughing and the finishing rolls. It further con-
sists in so arranging and operating the furnaces that after each rolling the metal
is placed in a furnace chamber separate from that from which it was taken and
kept separate from the packs of greater gauge being heated, so that they are not
chilled by the pack being inserted and may be subjected to a soft mild heat so
as to prevent scaling.
There is no objection to placing the plates first rolled, back into the furnace
from which the bars are being worked, as the bars have been subjected to a good
soaking heat, and the plates can be piled between the bars that are being worked
and heated to a good advantage, without hardening the bars. It should be under-
stood that the plates can be made from one bar instead of matching the plates from
two or more bars, and they can be finished on the fours, sixes, eights, or any
number of ply, depending upon the gauge of plate and weight of the bar worked.
In carrying my invention into practice the bars are heated in a chamber of a
furnace and then taken out and rolled into plate in a roughing mill. The plates
are then taken to an empty chamber of a second furnace and reheated, and being
taken to rolls are rolled and doubled into fours by a doubler, two plates having
been matched and rolled together. The fours are then reheated in a second
chamber of the second furnace, again rolled in the train, and doubled into eights.
The eights are then placed in the first empty chamber of the second furnace and
then taken out and finished in the rolls.
While the eights are being rolled, the bars are being roughed on the mill and
the plates successively placed in the second empty chamber of second furnace so
that the finishing roller as soon as he has finished the last pack, can begin with
another heat and work the finishing mill continously.
At the same time that the above operations are proceeding, other bars are heated
in a second chamber of first furnace, roughed on the mill, and then taken to a
second set of finishing rolls and finished thereon, the operation with these rolls
and a third furnace being the same as above described with reference to the first
rolls and the second furnace. It will be seen that in this operation the doubles
the fours, and the eights are each successively placed in an empty furnace chambe
so that the entering pack does not chill adjacent packs of less gauge, as formerly
and little or no skill is required in manipulating the packs, as they do not have
to be arranged with reference to other packs in the same chamber.
It will be understood that the two furnace chambers of each furnace may com
municate with cach other by openings in the separating partition, or that the
partition may be removed giving one large chamber in each furnace, this chambe

page_text: having two or more doors and in which substantially the same results may be
obtained.
In another modification the bars are heated in a chamber, rolled into plate in
rolls, then reheated in a second chamber, again rolled in the rolls and doubled by
a doubler. The fours thus formed are then placed in a chamber of a second
furnace, rolled in a second train, doubled, and placed in a second chamber of
second furnace as eights. The eights then being heated are finished in the second
train.
It will be seen that in this form, as in the first form, the packs of similar gauge
are placed in a furnace chamber separate from the prior pack and the finishing
mill is worked continuously.
It should be understood that in rolling the doubles on the roughing mill they
may not have as fine a surface as where they are rolled on a separate mill, but any
slight imperfections of the plate that are produced here can be overcome in the
succeeding reduction or reductions. Where the plates are finished on the fours,
the doubles can be worked partly on the roughing mill and partly on the finishing
mill, so as to divide the work and keep each mill working regularly
In a further modification the bars are heated in a furnace and then roughed
upon a mill. The bars thus formed are heated in a second furnace and being
matched together, the doubles are rolled in a second mill and doubled into fours
upon an adjacent doubler. The fours are reheated in a third furnace, rolled upon
a third mill and doubled into eights upon another doubler: The eights are then
heated in a fourth furnace and finished upon rolls. If suitable bar is employed
the bar may be rolled long enough upon the first rolling so as to double it, thus
saving one heating and rolling and requiring one less mill and two less furnaces.
But in any case the furnaces should be so arranged that the finishing mill can
work continuously and remain expanded to the same extent.
It will be seen that in any form of my invention the roughing is being done
while the finishing mill is in operation so that as soon as one pack is finished,
another is ready to be acted upon by the finishing mill. The doubles are all
finished and placed in a heating chamber before rolling the fours, and similarly
with the fours and eights, the packs of similar gauge all being successively placed
in the same furnace chamber or portion of the chamber separate from the packs
of greater gauge, i.e. those subjected to one less rolling operation.
In any of the furnaces described, or in other suitable furnaces which may be
employed in carrying out my invention, a single large chamber may be employed
with separate openings closed by doors or with a long opening closed by a series
of doors.
In the third modification I have described one set of rolls for roughing. It
is preferable, however, two have two rolls for this purpose, arranged side by side
and divide the work on the two rolls, as this reduction is much harder on the
rolls than any succeeding reduction, and these rolls should be placed close together,
so that either of them can be reached conveniently from the furnace, and the
roller can use them alternately.
The advantages of my invention will be apparent to those skilled in the art.
The placing of the packs in proximity to other packs in the furnace is avoided so
that the chilling of the packs is prevented, allowing them to be brought to a
much better condition for working. Moreover the high degree of skill before
necessary in inserting and replacing the packs is done away with, and this operation
may be carried out with cheap unskilled labour. The danger of scaling the sheets
is lessened and the output is increased.
As the finishing mills are worked in a regular or continous manner they are
kept at substantially the same temperature and hence preserve the same shape so
that a uniform action is obtained, giving a better product than was heretofore
possible.
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page_text: Improvements in the Manufacture of Black Plates or Sheets.
I, WILLIAM BURGELAND JOHNSON, of 4, Clayton Square, Liverpool, in the County
of Lancaster, 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, reference being had to the accompanying
drawings, forming part of this specification, in which:
_
Figures 1, 2 and 3 are diagramatic plan views, partly in section, showing
different forms of plants for the manufacture of black sheet or plate constructed
in accordance with my invention.
Heretofore in the manufacture of black plate or fine sheets, where two stands
of rolls have been employed, one for roughing and the other for finishing, a double
furnace has been employed, having two heated chambers, the operation being as
follows:
The tin plate bars are heated in one of these furnace chambers and then rolled
into plates upon the roughing train. The plate or plates are then placed in the
other heating chamber of the furnace and being brought to the proper temperature
are then rolled in the, finishing train and doubled. They are then replaced in the
same chamber, and again heated and rolled in the finishing train and doubled into
fours. After the doubling and trimming of one of the fours the pack, which has
cooled considerably, is replaced in the same furnace chamber which contains the
other packs of doubles. After the doubles are all rolled into fours one pack is
taken out, rolled and doubled into eights, during which operation the pack again
cools, and is again put back into the same furnace with the remaining packs of
fours, this cool pack tending to cool and harden the other packs in the furnace.
The remaining packs of fours are similarly rolled successively into eights and
replaced in the same furnace chamber and the packs of eights are then successively
taken out and rolled and finished. The placing of the cooled packs of fours in with
the doubles tends to harden and chill the doubles and render them unfit for rolling
and the cooled packs of eights have the same action upon the packs of fours. This
hardening of the packs being heated is overcome to some extent by raising the
temperature and making the heat more intense, but this action is objectionable as it
tends to scale the iron and to pit its surface. The heating of the packs demands
a high degree of skill as there are several packs in the same chamber at the same
time and cach pack inserted must be placed so that it will not interfere with the
taking out of the other packs to be worked.
Moreover, in the prior system of operation the rolling of the sheets has been a
difficult operation on account of the alternate heating and cooling of the rolls.
When the iron was rolled in the roughing train the finishing train remained idle
and hence would cool and contract, and after the iron had been roughed, the rough-
ing mill would stand idle and contract and cool, and hence both sets of rolls would
often break from the expansion and contraction consequent upon this alternate
heating and cooling.
Moreover, the cooling of the rolls changes their contour, so that it is extremely
difficult for the roller to obtain accurately rolled sheets. This is especially the case
in the finishing rolls which are turned in such a way that when they are heated
to a certain point their surfaces will be of the correct shape for rolling sheets; and
hence as the temperature falls while these rolls remain inactive, it will readily be
seen that the sheets cannot be properly rolled upon them after they have cooled
down.
Where a single stand of rolls was employed, upon which both the roughing and
finishing were carried out, this set of rolls would work in a more continuous

page_text: manner, but as the roughing of the heavy bars causes the rolls to expand much
more than after reduction, the sheets could not be rolled uniformly as the rolls
were constantly changing in shape and contour.
My invention overcomes these difficulties and it consists in roughing in one mill
and then passing the metal packs in a regular or continuous manner through a
finishing mill or mills so that the finishing rolls will be continuously maintained
at about the same temperature. These rolls can therefore be turned so that they
will be of the proper shape at this temperature and can be kept substantially of
this shape. It also consists in passing the metal continuously or regularly through
the roughing rolls, thus maintaining these rolls continuously at the same teni-
perature, as well as in passing the metal simultaneously and regularly or
continuously through both the roughing and the finishing rolls. It further con-
sists in so arranging and operating the furnaces that after each rolling the metal
is placed in a furnace chamber separate from that from which it was taken and
kept separate from the packs of greater gauge being heated, so that they are not
chilled by the pack being inserted and may be subjected to a soft mild heat so
as to prevent scaling.
There is no objection to placing the plates first rolled, back into the furnace
from which the bars are being worked, as the bars have been subjected to a good
soaking heat and the plates can be piled between the bars that are being worked
and heated to a good advantage, without hardening the bars. It should be under-
stood that the plates can be made from one bar instead of matching the plates from
two or more bars, and they can be finished on the fours, sixes, eights, or any
number of ply, depending upon the gauge of plate and weight of the bar worked.
In the drawings, referring to the form of Figure 1, 2 represents a roughing
mill and 3 and 4 finishing mills each provided with a doubling apparatus 5. 6, 7,
and 8 are heating furnaces, each preferably provided with two separate chambers,
these furnaces being preferably arranged one in front of each pair of rolls as shown.
In making black sheet with this plant, the bars are heated in the chamber à
of furnace 7 and then taken out and rolled into plate in the roughing mill 2.
The plates are then taken to the empty chamber e of furnace 6 and reheated, and
being taken to the rolls 3 are rolled and doubled into fours by the doubler 5, two
plates having been matched and rolled together. The fours are then reheated in
the chamber of furnace 6, again rolled in the train 3 and doubled at 5 into
eights. The eights are then placed in the empty chamber e of furnace 6 and then
taken out and finished in the rolls 3.
While the eights are being rolled, the bars are being roughed on the mill 2 and
the plates successively placed in the empty chamber f of furnace 6 so that the
finishing roller as soon as he has finished the last pack, can begin with another
heat and work the finishing mill continuously. At the same time that the abové
operations are proceeding, other bars are heated in the furnace chamber 6 of
furnace 7. roughed on the mill 2, and then taken to the finishing rolls 4 and finished
thereon, the operation with these rolls and the furnace 8 being the same as above
described with reference to the rolls 3 and the furnace 6. It will be seen that in
this operation the doubles, the fours, and the eights are each successively placed
in an empty furnace chamber so that the entering pack does not chill adjacent
packs of less gauge, as formerly, and little or no skill is required in manipulating
the packs, as they do not have to be arranged with reference to other packs in
the same chamber.
It will be understood that the two furnace chambers of each furnace may com-
municate with each other by openings in the separating partition, or that the
artition may be removed giving one large chamber in each furnace, this chamber
aving two or more doors and in which substantially the same results may be
obtained.
In the form of Figure 2, 9 represents a pair of roughing rolls and 10 a pair of
inishing rolls, 11 being the doubler for the rolls. 12 represents a furnace having

page_text: two chambers I and h and located in front of the roughing rolls; and 13 a furnace
having the two chambers and and located in front of the finishing train.
With this plant the bars are heated in chamber g, rolled into plate in rolls 9,
then reheated in chamber h, again rolled at 9 and doubled by the doubler 11.
The fours thus formed are then placed in chamber k of the furnace, 13, rolled in
train 10, doubled at 11, and placed in chamber 7 of furnace 13 as eights. The
eights then being heated are finished in rolls 10.
It will be seen that in this form as in the form of Fig. 1, the packs of similar
gauge are placed in a furnace chamber separate from the prior packs and the
finishing mill is worked continuously.
It should be understood that in rolling the doubles on the roughing mill they
may not have as fine a surface as where they are rolled on a separate mill, but any
slight imperfections of the plate that are produced here can be overcome in the
succeeding reduction or reductions. Where the plates are finished on the fours,
the doubles can be worked partly on the roughing mill and partly on the finishing
mill, so as to divide the work and keep each mill working regularly
In Fig. 3 I show a further form of plant, wherein 14 is the roughing mill; 15 the
mill for rolling the doubles; 16 the mill for rolling the fours, and 17 the mill for
finishing the eights. In front of these rolls I locate the furnaces 18, 19, 20, and 21,
each having two furnace chambers. 22 are the doublers for doubling the packs.
In operating this plant the bars are heated in the furnace 18 and then roughed
upon the mill 14. The bars thus formed are heated in the furnace 19 and being
matched together, the doubles are rolled in the mill 15 and doubled into fours upon
the adjacent doubler 22. The fours are reheated in the furnace 20, rolled upon
the mill 16 and doubled into eights upon the other doubler 22. The eights are
then heated in the furnace 21 and finished the rolls 17. If suitable bar is employed
the bar may be rolled long enough upon the first rolling so as to double it thus
saving one heating and rolling and requiring one less mill and two less furnaces.
But in any case the furnaces should be so arranged that the finishing mill can work
continuously and remain expanded to the same extent.
It will be seen that in any form of my invention the roughing is being done
while the finishing mill is in operation so that as soon as one pack is finished,
another is ready to be acted upon by the finishing mill. The doubles are all
finished and placed in a heating chamber before rolling the fours, and similarly
with the fours and eights, the packs of similar gauge all being successively placed
in the same furnace chamber or portion of the chamber separate from the packs
of greater gauge, i.e. those subjected to one less rolling operation.
In any of the furnaces shown, or in other suitable furnaces which may be
employed in carrying out my invention, a single large chamber may be employed
with separate openings closed by doors or with a long opening closed by a series
of doors.
In Fig. 3 I have shown one set of rolls for roughing. It is preferable, however,
to have two rolls for this purpose arranged side by side and divide the work on the
two rolls, as this reduction is much harder on the rolls than any succeeding reduc-
tion, and these rolls should be placed close together, so that either of them can
be reached conveniently from the furnace, and the roller can use them alternately.
The advantages of my invention will be apparent to those skilled in the art.
The placing of the packs in proximity to other packs in the furnace is avoided so
that the chilling of the packs is prevented, allowing them to be brought to a
much better condition for working. Moreover, the high degree of skill before
necessary in inserting and replacing the packs is done away with, and this opera-
tion may be carried out with cheap unskilled labor. The danger of scaling the
sheets is lessened and the output is increased.
As the finishing mills are worked in a regular or continuous manner they are
kept at substantially the same temperature and hence preserve the same shape so
that a uniform action is obtained, giving a better product than was heretofore
possible.

page_text: Many changes may be made in the form and arrangement of the furnace, the
rolls and the doublers, without departing from my invention.
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. In the manufacture of black plate or sheets, the method of keeping the finish-
ing rolls of the same shape, consisting in roughing upon another mill and passing
the packs in a continuous or regular manner through the finishing rolls.
2. In the manufacture of black plate, the method of obtaining uniform sheets,
consisting in passing metal simultaneously through the roughing and finishing
rolls.
3. The method of making uniform sheets consisting in passing the metal simul-
taneously through the roughing and finishing rolls, and operating both the rolls
in a continuous or regular manner.
4. The method of making black sheets consisting in heating the metal, breaking
it down upon the roughing rolls inserting it in a furnace chamber at a point remote
from the packs being reduced, rolling and doubling the plates, heating these plates
in a separate chamber, and then finishing rolling the sheets.
5. The method of making black sheets consisting in heating the doubles in a
furnace chamber, rolling and doubling them into fours, placing the fours in a fur-
nace chamber at a point remote from the doubles so as to avoid chilling the doubles,
rolling the fours into eights, heating them separately from the fours, and then
rolling the eights into finished sheets.
6. The method of making black sheets consisting in heating a pack, rolling and
doubling it, and inserting it in a furnace chamber at a point remote from the packs
being rolled so as to avoid chilling them.
7. The method of making black plate consisting in rolling the packs in a con-
tinuous manner upon a finishing mill and reheating each doubled pack by placing
it in a furnace chamber at a point remote from the other packs which have been
subjected to one less rolling operation.
8. The method of making black sheets consisting in breaking down the metal
upon roughing rolls during the operation of the finishing rolls, and operating the
finishing rolls in a regular manner upon the plates from the roughing rolls.
9. The combination with a roughing mill and a finishing mill, of a furnace in
front of each mill, the furnace being so arranged that each set of similar gauge
are inserted in an empty furnace chamber.
Tutad thin
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