IMPROVEMENTS IN THE MANUFACTURE OF TIN AND TERNE PLATE
Year: 1878

page_text: LETTERS PATENT to Edmund Morewood, of Llanelly, in the County of Caermar-
then, Tin Plate Manufacturer, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF TIN AND TERNE PLATE."
Sealed the 10th May 1878, and dated the 28th January 1878.
PROVISIONAL SPECIFICATION left by the said Edmund Morewood at the
Office of the Commissioners of Patents on the 28th January 1878.
EDMUND MOREWOOD, of Llanelly, in the County of Caermarthen, Tin Plate
Manufacturer. "IMPROVEMENTS IN THE MANUFACTURE OF TIN AND TERNE
PLATE."
This Invention has for its object improvements in the manufacture of tin and
terne plate.
For some years past I have been occupied with attempts to produce tin and terne
plate at one operation, with apparatus so arranged that a bare plate introduced into
it at one end is delivered a finished tin or terne plate at the other end. Until now
these attemps have not been completely successful.
I have found that success to a great extent depends on the employment of a
suitable flux at the entrance side of the apparatus. The flux which I now employ
is a mixture of rosin, tallow, and other grease, or rosin or tallow, either separately
or mixed with other grease, or together. But these fluxes can only be employed
when a high temperature is inaintained in the coating metal pot which necessarily
leads to the production of a certain amount of "scruff." Hence these fluxes are useless
for working in this manner, unless there be also special arrangements on the exit
side of the apparatus to prevent this scruff (which is carried forward by the plates)
accumulating on the surfaces of the finishing rollers, for it is essential to the produc-
tion of perfect plates, that the surfaces of the finishing rollers should be kept clean.
It is also essential to the practical use of the fluxes mentioned above that a suitable
flux box should be provided to contain them. I use a flux box or receptacle of a
funnel-like form, having a long and narrow opening at the bottom, where it dips
Ping G71

page_text: into the metal in the tinning pot, but widening out above to several times the area
of the opening at the bottom. The flux as it becomes heated, by the metal, at the
small area where it is in contact with it, rises and mixes with the larger body of
flux above. In this way overheating of the flux is avoided, and a suitable gra-
dation of temperature is maintained in the flux box, so that the moist plate as it
enters, meets first with comparatively cool flux, but traverses in descending hotter
flux suitable to prepare it for the coating metal.
I arrange apparatus in this flux box, so as to have more than one plate under the flux
at a time, and by means of a lever, or spring, or trap the plate is detained in its
passage through the flux, and when released is in a more suitable state for taking
the melted metal when it enters the coating metal than it would be if passed directly
through the flux.
The way in which I prevent the scruff from accumulating upon the surface of the
finishing rollers or the rollers revolving in the finishing grease is by keeping their
surfaces washed with clean coating metal supplied to them from a reservoir provided
for the purpose, and I place troughs underneath the rollers to retain this clean metal,
so that their under sides may be constantly immersed in it. With this arrangement
any particle of scruff which may be brought to the rollers, will at once, as the rollers
revolve, be transferred to the metal in the small troughs beneath, and will remain
floating in these troughs until it is skimmed off by the workman.
I also in some cases employ the clean coating metal supplied to the finishing part
of the apparatus to wash the surfaces of the plates before they reach the last pair
of rollers, so as, as far as possible, to prevent the scruff reaching the last pair of
rollers..
I arrange two surfaces of metal with a narrow space between them, through
which the plate rises, and as it comes up it meets clean coating metal flowing
down between the surfaces.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edmund Morewood in the Great Seal Patent Office on the 27th
July 1878.
EDMUND MOREWOOD, of Llanelly, in the County of Caermarthen, Tin Plate
Manufacturer, "IMPROVEMENTS IN THE MANUFACTURE OF TIN AND TERNE
PLATE."
This Invention has for its object improvements in the manufacture of tin and
terne plate.
For some years past I have been occupied with attempts to produce tin and terne
plate at one operation, with apparatus so arranged that a bare plate introduced into
it at one end is delivered a finished tin or terne plate at the other end. Until now
these attempts have not been completely successful.
I have found that success to a great extent depends on the employment of a
suitable flux at the entrance side of the apparatus. The flux which I now employ
is a mixture of rosin, tallow, and other grease, or rosin, or tallow, either separately
or mixed with other grease, or together. But these fluxes can only be employed
when a high temperature is maintained in the coating metal pot, which necessarily
leads to the production of a certain amount of "scruff." Hence these fluxes are
useless for working in this manner, unless there be also special arrangements on the
exit side of the apparatus to prevent this scruff (which is carried forward by the
plates) accumulating on the surfaces of the finishing rollers, for it is essential to the
production of perfect plates that the surfaces of the finishing rollers should be kept
'clean.
It is also essential to the practical use of the fluxes mentioned above, that a
suitable flux box should be provided to contain them. I use a flux box or receptacle
of a funnel-like form, having a long and narrow opening at the bottom, where it
dips into the metal in the tinning pot, but widening out above to several times the
area of the opening at the bottom. The flux, as it becomes heated by the metal at
the small area where it is in contact with it, rises and mixes with the larger body of
flux above. In this way overheating of the flux is avoided, and a suitable gradation of
temperature is maintained in the flux box, so that the moist plate as it enters meets
first with comparatively cool flux, but traverses in descending hotter flux suitable
to prepare it for the coating metal.
I arrange apparatus in this flux box, so as to have more than one plate under the
flux at a time, and by means of a lever or spring, or trap, the plate is detained in
its passage through the flux, and when released is in a more suitable state for taking
the melted metal when it enters the coating metal than it would be if passed
directly through the flux.
The way in which prevent the scruff from accumulating upon the surface of
the finishing rollers, or the rollers revolving in the finishing grease, is by keeping
their surfaces washed with clean coating metal supplied to them from a reservoir
provided for the purpose, and I place troughs underneath the rollers to retain this
clean metal so that their under sides may be constantly immersed in it. With this
arrangement scruff which may be brought to the rollers will at once, as the rollers
revolve, be transferred to the metal in the small troughs beneath, and will remain
floating in these troughs or become mixed with the flux at the back of the rollers, :
and may be skimmed off by the workman.
I also in some cases employ the clean coating metal supplied to the finishing part
of the apparatus to, wash the surfaces of the plates before they reach the last pair of
rollers so as, as far as possible, to prevent the scruff reaching the last pair of rollers.
I arrange two surfaces of metal with a narrow space between them, through
which the plate rises, and as it comes up it meets clean coating metal flowing
down between the surfaces.

page_text: In order that my Invention may be most fully understood and readily carried
into effect, I will proceed to describe the Drawings hereunto annexed, which
Drawings I may remark are similar to the Drawings which I aunex to the Specifi-
cation of another Patent granted to ine, bearing even date with the Patent of which
this is the Specification, the said Drawings being there employed to illustrate points
of Invention different from those which are claimed under the Patent to which this
Specification applies..
Figure 1 is a longitudinal section of apparatus intented especially for the manu-
facture of tin plate at one operation, but also very suitable for the manufacture of
terne plate.
A, A¹, is the pot in which the coating metal is contained, it is divided into two
parts by the air space or flue B, which serving as a heat barrier, obstructs the
passage of heat from one part of the pot to the other, and admits of the metal in
the part A being kept at a much higher temperature than the metal in the part A¹;
although there is a passage connecting the two parts of the pot of sufficient width
to give ready passage to the plates to be coated. The pot is set in brickwork as is
usual, and beneath the part A a fire-place is formed for heating the pot; and it is
so arranged that the heat from this fire shall not reach the bottom and outer sides
of the part A', beneath which however another fire-place is formed, the use of this
second fire being to warm the part A' when commencing work after the apparatus
has been allowed to get cold. At other times and when in regular work no fire is
used in the fire-place under the part A', but a current of cold air is allowed to pass
through it to the chimney whenever the temperature of the part A¹ of the pot tends
to rise higher than the workman desires, and this current of air carries away heat
from this part of the pot.
Air currents can also be allowed to pass to the chimney through the space or
flue B, and through the similar space or flue B₁; these air currents can be controlled
by means of dampers.
Other means may be taken to cool the end A¹ of the pot when requisite, but I
find the application of air currents the most convenient. C, C, are cast-iron frames
introduced into the part A of the pot at a short distance from the sides. These
frames carry the bearings of the metal-coated rollers D, D, which are geared
together by spur wheels contained in the spaces between the frames C and the
sides of the pot.
The arrangement of this driving gear is indicated by dotted lines. The part A¹
of the pot contains other rollers D', D¹, their bearings are held in frames similar to
the frames C, but not shown in the Drawing. These rollers are driven at the same
surface speed as the rollers D by gearing indicated by dotted lines; E is the
bath or vessel, in which is contained the finishing grease, usually palm oil, or a
mixture of palm oil and tallow. A plan of this bath or vessel is given in Figure 2.
Within the bath or vessel E, the frames F for holding the bearings of the rollers G
are received and secured; dotted lines show the gear for driving these rollers; H is
the entrance flux box; its lower and smaller end dips into the metal contained in
the part A of the pot.
The flux box H is charged with a flux consisting as I prefer of sixty-seven parts
of rosin, twenty-three parts of tallow, and ten parts of palm oil. Within the flux
box H there are stationary guides H', H', and in connection with these there are
other guides H2 which are moveable about centres H2*, and springs or weights tend
to close the lower ends of the moveable guides H2 against the fixed guides H'.
There are thus four spaces in the flux box H shown in the Drawing between the
fixed and the moving guides, and each of these spaces is adapted to hold a plate to
be coated. In working the apparatus each of these spaces in turn receives a plate
from the hand of the workman, who as he introduces each plate moves the guide. H²

page_text: corresponding to the space which he is charging, in order that the plate which the
space already contains may be able to pass out, and with the new plate he pushes
down the plates which is to pass out until the first pair of the rollers D take hold
of it. By this arrangement the plates are detained in the flux long enough to
bring them to a suitable state and temperature to enter the coating metal.
The number of plates which the flux box is adapted to retain at one time may
be varied, four however is a suitable number to ensure proper preparation when
working rapidly. The pot is filled with metal, so as completely to cover the first
pair of rollers D, and so that these rollers may be clear of the scruff or impurity
which floats upon the surface of the molten metal. The plates are carried forward
by the rollers D aided by the guides C', C¹, which are fixed to the side frames, and
in their passage the somewhat highly heated metal in the part A of the pot takes
on to the plate and gives to it a sound coating. The plate then passes on through
the narrow opening left for it into the cooler part A' of the pot. The temperature
of this plate is thus rapidly reduced, and the coating upon it is brought to a state
fit for finishing.
If any of the scruff which forms in the hot end of the pot should be carried
forward with the plate into the part A¹, a large portion of it will rise immediately
to the surface of the metal, and the flue B₁ acting as a barrier will prevent it
reaching the finishing grease contained in the bath or vessel E; the plate emerging
from the molten coating metal enters the finishing grease, and is carried up through
it by the coated rollers G. The distances between these rollers can be adjusted by
means of regulating screws acting through springs, and in the case of the upper-
most rollers, where it is necessary that the adjustment should be completely under
control, the screws act upon the bearings of the roller through spring levers.
Beneath the uppermost rollers G troughs I, I, are fixed, and in these troughs
clean coating metal is contained, and there is grease at the back of the rollers.
This metal serves to keep the surfaces of the rollers in good condition by washing
off scruff or impurities which is brought to them by the plates rising up through
the grease from the coating metal. A good supply of metal given to the troughs I
will cause the surfaces of the plates to be well washed.
The supply for the troughs I is drawn from supply vessels, which however are
not shown in the Drawings. There is a supply vessel for each trough. It is
arranged immediately in front of or behind the trough, as the case may be, and is
made long and narrow, so that it may occupy but little room in the bath or vessel E,
which however may be made somewhat wider than the Drawings represent, in
order the better to accommodate these supply vessels. The supply vessels are
immersed in the grease in the bath or vessel E, the heat from which serves to keep
the metal in the supply vessels in a molten state, and with the same object the
supply vessels may also be made deep, so that the lower part of the supply vessels
may dip down into the metal in the pot A¹, in order that the heat may be more
rapidly communicated from the metal in the pot to the supply vessels; or in place
of making the supply vessels of this great depth, they may be made with fins or
legs of metal long enough to become immersed at their lower ends in the metal in
the part A of the pot. Slits or orifices in the sides of the supply vessel allow the
metal to flow out into gutters or pipes, which lead the metal into the troughs I.
The supply can be regulated by slides covering the slits or orifices to a greater or
less extent.
The extensions E¹, E', of the bath or vessel E overhang the pot, and they have
floors or bottoms, whereas the central part of the bath or vessel E is without a
bottom, the grease in it resting on the melted metal on the exit side of the coating
pot. On one side of the pot a notch or recess is formed to allow of the bottom of
the extension E¹ on this side to be at a somewhat lower level than the edge or
flange of the pot, so that occasionally, as herein-after explained, the pot may be
filled sufficiently full of metal to cause it to flow over the bottom of the

page_text: extension E¹ on this side, although the ordinary level at which I work is just
beneath it.
Figure 3 is an elevation of the extension E'; it is closed by a slide E*, also seen
in section in Figure 4. The slide works in a groove, and a little packing of hemp
or hempen fabric may advantageously be placed in the groove, so that the slide
may work easily and yet remain tight. From the nature of the grease however but
little difficulty will be found in keeping the slide sufficiently tight, and any grease
which may leak out flows to a cistern in which it is collected.
When it is desired to draw off impurities from the surface of the metal beneath
the rollers G, metal is put into the pot until the metal rises into the end E¹ to
which the slide Ex is fitted, and then the slide is slightly raised, so that the metal
may flow out beneath it, and with this metal grease settlings & impurities floating
on its surface will pass out.
I prefer to arrange slides Ex in connection with the extension at each end of the
bath or vessel E, and I also provide other slides or moveable partitions, by which
the extensions can be shut off from the body of the bath or vessel E. By thus
closing for a time the communication between the bath and the connections the
warming up of the apparatus when commencing to work is facilitated, and the
extensions or ends are rendered more accessible for cleaning; as is seen in Figure
there is a pipe fitted with a tap in connection with each of the extensions or
ends E¹, they enter near to the bottom. One of these pipes is in connection with a
cistern at a higher level, in which a supply of cool but fluid and suitable grease is
kept, and by adjusting the tap, or preferentially by means of a float in the exten-
sion E¹, the amount of this cool grease flowing into the bath or vessel E can be
regulated.
The other pipe leads to a receiver at a lower level, and it serves for the outflow
of hot grease, and of grease which by use has become thick, and which requires to
be allowed to settle and deposit impurities before it will be again suitable. By
means of the tap the outflow can be adjusted, and so a perfect control is obtained
both of the temperature and quality of the grease in the bath or vessel E. The
supply of grease may be poured into the bath or vessel by hand from time to time,
although much less conveniently than by the arrangement which I have described;
but removal of the grease by baling out would not give any satisfactory result, as
the overheated and impure grease near the bottom could not be thus removed
conveniently.
Figure 5 is a longitudinal section of an apparatus which differs in some details
from that shown in Figure 1. This apparatus is intended especially for the manu-
facture of terne plate, but it may be used also for the manufacture of tin plates,
although I do not recommend it for that purpose. It is provided with a flux box
on the entrance side, which is of a funnel-like form, and it dips at its lower end into
the metal in the pot to a depth sufficient to maintain the column of the flux. On
the exit side the bath or vessel E has formed together with it troughs I containing
clean coating metal for the supply of the uppermost rollers. The bath or vessel E
has extensions E¹, as already described, but they are shallower than the extension
in Figure 1, as in this case the finishing grease stands considerably below the level
of the uppermost rollers; and there is an air space between the surface of the
*grease and the nip of these rollers.
Where the bath or vessel containing the grease on the exit side is deep, as it is
in the apparatus which I prefer for tin plate, I sometimes, in order to have more
complete control over the working, provide air flues in connection with it, as is
shown in Figure 6. In this Figure K, K, are flues running along the sides of the
bath or vessel E, and there are suitable connections provided with dampers, by
which either cold air to carry away heat can be admitted through these flues to the
chimney, or by which, in commencing to work when the apparatus is cold, hot air
from the fire may be conducted. In some cases I find it advisable to fix face plates
1

page_text: in the bath or vessel E, and the plates under treatment have to pass between them
as they rise to the uppermost rollers.
L, L, in Figure 6, represent the face plates made of steel or wrought iron; they
are themselves carefully coated before they are put to work, and they are supplied
with clean coating metal either by causing the troughs I, which supply the rollers
above, to overflow, or as is to be preferred a separate supply from the store vessel is
conducted to them by channels provided for the purpose. The face plates are set
at a distance apart, such that the plates can pass quite freely between them; but
nevertheless being stationary they retain to some extent the supply of coating metal
between them, and this metal washes the surface of the plate, and tends to prevent
impurities reaching the surfaces of the uppermost rollers.
Where face plates are not employed it is sometimes advisable to give a separate
supply of coating metal to a pair of the rollers G below the uppermost pair, and
for this purpose troughs I may advantageously be applied to such rollers. Thus I am
enabled to ensure that the plates shall be well washed with clean metal before they
reach the uppermost rollers without giving too liberal a supply of metal to the
uppermost rollers themselves, which might cause the plates to be coated more
thickly than was required.
Although I consider the most advantageous way of working is with a divided
pot kept at different temperatures at its different parts, as already described, never-
theless I can employ two separate pots of coating metal, the one hot, and the other
cool. This I do by providing rollers immersed in clean molten metal or in liquid
flux, such as grease, to convey the plates from one pot to another.
The arrangement is shewn in Figure 7. L, L, are a pair of conveying rollers,
one larger than the other in order that the plate may take a curved course in
leaving them. These rollers raise the plate out of the hotter pot; they are driven
at the same surface speed, and are provided with troughs kept supplied with clean
coating metal separate from that in the coating pot.
Any impurities which the plates may bring over with them will be removed from
the rollers by the metal in which they are bathed or mix with the flux on the back of
these trough rollers, and can be skimmed off by the workman from time to time from
the surface of the metal in the troughs at the back of the rollers. Curved guides
ensure the entrance of the plates, leaving the rollers L between the rollers M, M, and
these revolve in grease or flux supported upon the surface of the metal in the cooler
pot, the rollers themselves being above the level of the metal.
In consequence of the lower temperature maintained in this pot, grease or flux
can be maintained in good order upon its surface. Other rollers carry the plate
forward, as already described.
In the arrangement of apparatus, and the method of working herein-before
described, there are several different points of invention involved, and some of these
I claim under another Patent granted to me, and bearing even date with the Patent
of which this is the Specification. In this Specification, and under the Patent to
which it applies, I claim,-
First. In the manufacture of tin or terne plates, when, by causing them to traverse
through coating metal having a lower temperature at the exit side than at the entering
side, the plates are coated at one operation, causing the plates to enter the coating pot
through a flux consisting of a mixture of rosin, tallow, and other grease, or rosin or.
tallow, either separately or mixed with other grease, or together, and in emerging
to pass between finishing rollers supplied with clean coating metal, and revolving
in contact with grease.
Second. In the manufacture of tin or terne plates, as above, causing the plates to
enter the coating pot through a flux box, dipping at its lower end into the metal
contained in such pot, and capable of retaining the plates, and after they have been
held back for a time in the flux, delivering them one at a time into the melted
coating metal.
Third. Arranging a store vessel or reservoir immersed in the finishing grease to

page_text: retain in a melted state clean coating metal, which is allowed to pass by a regulated
passage from the store vessel to supply the rollers, face plates, or finishing
instruments.
In witness whereof, I, the said Edmund Morewood, have hereunto set my
hand and seal, this Twenty-seventh day of July, in the year of our Lord
One thousand eight hundred and seventy-eight.
מזוזווז.
HARDWOOD
EDMUND MOREWOOD. (L.B.)