IMPROVEMENTS IN APPLYING TIN OR OTHER COATING METAL TO METAL SHEETS AND OTHER SURFACES OF METAL. PROVISIONAL SPECIFICATION
Year: 1873

page_text: LETTERS PATENT to Edmund Morewood, late of Rock Cottage, Briton
Ferry, in the County of Glamorgan, now of Llanelly, in the County
of Carmarthen, and John Henry Rogers, of Llangennech Park,
near Llanelly, in the County of Carmarthen, Tin Plate Manu-
facturers, for the Invention of "IMPROVEMENTS IN APPLYING TIN OR
OTHER COATING METAL TO METAL SHEETS AND OTHER SURFACES OF METAL.
PROVISIONAL SPECIFICATION left by the said Edmund Morewood and
John Henry Rogers at the Office of the Commissioners of Patents,
with their Petition, on the 24th September 1873.
We, EDMUND MOREWOOD, late of Rock Cottage, Briton Ferry, in the
County of Glamorgan, now of Llanelly, in the County of Carmarthen,
and JOHN HENRY ROGERS, of Llangennech Park, near Llanelly, in the
County of Carmarthen, Tin Plate Manufacturers, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN APPLYING TIN OR OTHER
COATING METAL TO METAL SHEETS AND OTHER SURFACES OF METAL," to be as
follows:-

page_text: coating metal, especially from the first coating or tinning pot, and also
by the deterioration of the melted coating metal coating kept at the
ordinary heat of the tinning or first coating pot.
In order to avoid much of this loss, and to perform the tinning or
coating with a smaller quantity of coating metal in a melted state, we
arrange machinery, vessels, and melted metal so as to make it
unnecessary to submerge the plates, either partially or wholly, in the
melted metal; we proceed as follows:-We prepare the cleaned iron
plates, which are to be coated by immersing them in a pot or vessel
filled with melted grease or flux, and after allowing them sufficient time
therein to get their surfaces properly prepared (or having prepared them
by any convenient mode for taking the melted coating metal) we pass
them between rollers provided with feeding troughs containing coating
metal. The surfaces of the rollers are thus coated with melted metal
and fed with the coating metal, in contact with which they revolve.
Sometimes we use other similar rollers and troughs supplied with a
sharp flux; the rollers revolving in contact with the sharp flux will so
act upon the surfaces of the plates passing between them that the
succeeding pair of coating rollers will readily plant a coating on the
surface of the plate. In such case the immersion and standing in flux
is not necessary.
We arrange and shape the troughs and rollers so that we have the
means of regulating the height of the coating metal in the troughs, and
the quality and quantity of the supply of the melted coating metal
furnished to the rollers.
We make the troughs of such size and form and place them so that
the lower part of the coated roller dips into the melted metal contained
in them.
"Sometimes we arrange the rollers gathering coating metal from the
trough so as to feed a pair of other rollers revolving against them, and
having their surfaces in contact with them, and then the latter rollers
coat the plates instead of the rollers which gather the metal. In this
case the upper part of the coating roller may be fed instead of the
lower.
We also form and place the troughs so that the melted coating metal
therein can be freed from scruff or other impurities from time to time.
In thus performing the coating without making use of the first tinning

page_text: or coating pots or the wash pot, or the process of brushing over, we find
it important to use more than one pair of coating rollers, having
coating metal on their surfaces working in connection with troughs as
described.
Sometimes we cause the plates to pass direct from one pair of rollers
to another from the commencement to the completion of the coating
processes. In other cases the rollers may be arranged in two or more
separate series.
Sometimes we immerse coating rollers provided with feeding troughs
as above described in a bath of heated flux or grease. Before passing
from the flux into the nip of the coating rollers or in an after stage of
the process a slight or imperfect coating may be given to the plate in
process of coating by a dip into a pan or vessel of shallow metal melted,
but we find this unnecessary.
The object of causing the plates to pass between several pairs of
rollers is to complete and improve the quality and soundness of the
coating. By having this arrangement of several troughs in connection
with several coating rollers we are enabled to feed with various qualities
and kinds of metal, and various qualities and kinds of flux at different
stages of the process, and we substitute flux in some of the troughs for
metal when we wish to vary the quality or kind of flux at different
stages of the process, or to economise the quantity in use.
When the plates of iron or other metal pass through a second or after
pair of coating rollers we aim to keep the coating metal supplied to the
after rollers so clean and of such character as to wash and improve the
coating on the surface of such plates, and travelling through flux
between successive pairs of rollers so acts upon the surface of the plates
as to fit them for being mended and improved by the after pair of rollers.
Wire may be coated in a similar manner.
When we use in the earlier stage of this coating process such a flux
as it is desirable but difficult afterwards to remove from the surface of
the plate, we cause the plates to pass through an after pair or pairs of
coated rollers, whose nip is kept as clear from flux as possible, and the
roller is kept clean by a backing of suitable flux, as described in my
(Edmund Morewood's) Patent of 27th March 1869, No. 942, and also
have a drain chamber or space beneath the rollers.
:

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edmund Morewood and John Henry Rogers in the
Great Seal Patent Office on the 24th March 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, EDMUND
MOREWOOD, late of Rock Cottage, Briton Ferry, in the County of
Glamorgan, now of Llanelly, in the County of Carmarthen, and JOHN.
HENRY ROGERS, of Llangennech Park, near Llanelly, in the County.of
Carmarthen, Tin Plate Manufacturers, send greeting.
J
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of September, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said Edmund Morewood and John Henry
'Rogers, Her special license that we, the said Edmund Morewood and
John Henry Rogers, our executors, administrators, and assigns, or such
others as we, the said Edmund Morewood and John Henry Rogers, our
executors, administrators, and assigns, should at any time agree with
and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN APPLYING TIN OR OTHER COATING METAL TO METAL SHEETS
AND OTHER SURFACES OF METAL," upon the condition (amongst others) that
we, the said Edmund Morewood and John Henry Rogers, our executors
or administrators, by an instrument in writing under our or their hands
and seals, or under the hand and seal of one of us or them, should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Edmund Morewood, on behalf of
myself and the said John Henry Rogers, do hereby declare the nature
of the said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following
statement thereof, that is to say :-

page_text: In coating plates of iron with tin or other coating metal in a melted
state it is well known that there is a great loss by evaporation of the
coating metal especially from the first coating or tinning pot, and also by
the deterioration of the melted coating metal kept at the ordinary heat
of the tinning or first coating pot.
In order to avoid much of this loss and to perform the tinning or
coating with a smaller quantity of coating metal in a melted state
we arrange machinery, vessels, and melted metal, so as to make it
unnecessary to submerge the plates either partially or wholly in the
melted metal, and this we do by causing the molten coating metal to be
supplied to the sheets or other surfaces whilst they are travelling
through a bath of heated flux, which is effected by rollers which are kept
perpetually supplied with coating metal.
In applying coating metal according to our Invention to metal sheets
or suitable surfaces (which we shall speak of as plates) by means of
coating rollers we proceed as follows:-We first clean or pickle the
plates of metal with hot and strong acid, or as it is usully termed
"high," and after washing them well in clean water we use them fresh,
say an hour or two after they have been cleaned and without allowing.
them to stand long in water. We then place them wet or damp and
separately by preference in a grease pot or vessel heated to about the
melting point of the metal with which they are to be coated.
.
The grease pot is provided with an overflow gutter or pipe and an
arrangement for the return in a more solid state of the grease which
froths up and flows over when the wet iron plates are deposited in
the hot grease. Such an arrangement as that described in Edmund
Morewood's Patent of 22nd June, 1870, No. 1780, will answer.. In this
grease pot we usually have at one time say 40 or 50 iron plates of the
size technically described as 20×14.C thickness, keeping them as much
apart as we conveniently can by means of pins or otherwise.
The plates are deposited and removed as nearly as may be in rotation,
and whilst in this grease pot they are immersed in hot and tolerably solid
grease. From this grease pot we withdraw the hot plates and treat
them by our improved process, according to which we place them
between a pair of coating rollers contained in a bath of suitable flux,
such as grease, if coating with melted tin, such grease or other flux being
kept, say at about 100 degrees Fahrenheit above the melting point of

page_text: .
.
the coating metal. These rollers pass the plates in succession to other
rollers, all contained in the same bath of flux. We keep the coating
rollers on the entrance side of the coating bath of grease or other flux
well supplied with melted coating metal.
In practice we use a pump for pumping up the coating metal which
drops or runs down from the coating rollers to the bottom of the bath
or pot. Such pump being worked by the engine which drives the
rollers. We cause the metal thus pumped up to flow between the
entrance coating rollers, and sometimes we place nip pieces between the
ends of the pair of rollers, as stated in a Provisional Specification filed by
us, and dated the 23rd day of March 1874, in order to prevent the fluid
coating metal running out too quickly from between the coating rollers.
We make no claim under the present Patent in respect to such nip
pieces.
We give a supply of metal of better quality to the pairs of rollers on
the after or exit side of this pot or bath of grease or flux.
Between the entrance and the exit rollers we arrange intermediate
rollers, the comparatively long travel through flux between successive
pairs of rollers in the manner proposed by us mends and improves
the first hasty and imperfect coating and fits it for being well and
soundly finished by the after pairs of rollers.
We have two and sometimes three pairs of coating rollers on the
entrance side, and two and sometimes three pairs on the exit side, some
iron plates taking coating with more difficulty than other plates. We
make these coating rollers about six inches diameter. We place iron
troughs under these rollers. These troughs contain coating metal or
flux, and the surface of the rollers is coated or washed or fed by revolving
therein.
We regulate the height of the coating metal in the troughs by the
supply produced from the pump working at a quicker or a slower speed.
The quality of that pumped up from the bottom of the bath will be
inferior in consequence of use to the fresh melted metal from the
reservoir which is supplied to the exit rollers. When starting the
process we completely coat the surface of the coating rollers by
immersing them in stale grease at a temperature above that of the
molten metal and keeping them revolving while coating metal is
supplied to them.

page_text: r
Drawing No. 1 represents the coating grease pot with troughs and
rollers and machinery, together with a reservoir; also with a revolving
drum and arms and guides. This mechanism is also described in our
Provisional Specification, dated the 23rd day of March, 1874, and it is
not claimed under the present Patent. Or the plates may be caused to
travel between the drum and small rollers and guides, as shewn in
· Drawing 2, an arrangement which with some of its adjuncts our said
Provisional Specification also describes, and to which under the present
Patent we make no claim. In this case we coat the drum with melted
coating metal.
We make the drum of wrought iron, and fill it with sand, whiting, or
plaster of Paris.
Drawing No. 1 is a vertical section. The plate is placed in the flux
box A, and at the right moment the finger H, acted upon by a catch
and suitable levers as shewn, allows the plate to fall into the nip of the
· rollers B, B, below which there is an iron receiver C, C, which collects
the coating metal as it drops from the rollers B, B, and brings it into
contact with the plate as it passes downwards. The rollers B, B, are
supplied with melted coating metal by the pump and gutter J. After
the plate leaves the lower rolls B, B, it falls on to pegs K. fixed in the
drum E, and is carried round between the drum E and the guides D, D,
until it enters the nip of the rollers F, F, through which it makes its
exit. The rollers F, F, are supplied with coating metal of good quality
from the tank G. The supply to the tank G may be by means of a
pump. Any metal which falls from the rollers F, F, is taken up by the
pump J and supplied to the rollers B. Thus the rollers F, F, always
receive the fresh metal, and after being used upon them the metal passes
to the rollers B, B, or the supplies may be kept entirely distinct, that to
the rollers F being of the better quality.
The Drawing No. 2 shews a vertical section of a somewhat different
arrangement. Here the plate passes through the flux box A into the
nip of the rollers B, B. These are fed with coating metal from the
gutters C, C, which are supplied by a pump or by other convenient
means. The rollers also revolve in troughs D, D, which contain melted
coating metal, and are replenished by the metal supplied to the rolls.
The plate then passes on by guides E, E, between rollers F, F, and the
drum G, thence through the guides H, H, into the nip of the rollers J, J,

page_text: "
which also revolve in troughs of melted coating metal L, L, and from
between the upper pair of rollers J, J, the plate makes its exit from this
coating bath. The troughs L, L, of the upper pair of rollers J, J, are
supplied with melted coating metal of a better quality from a small
tank K. At the ends of the rollers B, B, and J, J, there are nip pieces
B2, B2, which ride in grooves in the rollers and hinder the coating metal
from running out at the ends of the rollers as fast as it would do other-
wise. The drum and rollers are all driven by wheels gearing into each
other, so that they have the same surface speed. The hollow box M
displaces a large amount of grease or flux, so that by raising or lowering
it the level of the grease is readily altered.
It will be desirable after the sheets are delivered by the upper or exit
rollers J, J, Figure 2, or F, F, Figure 1, to submit them to a finishing
process. We prefer that the process should be that described in our
Specification, No. 3126, bearing even date herewith. The finishing
process may form a separate operation, but we prefer that it should be
performed as the sheets rise out of the coating pot from the upper
rollers J, J. These rollers may if necessary be placed somewhat lower
than the Drawing shows in order to admit of the finishing rollers and
apparatus being placed above them.
If we are coating with tin only, and if it is important that the plates
should have the usual color, finish, and appearance of tin plates made
in the ordinary way, we finish them by bringing them out through
coated rollers which revolve in contact with grease up to and an inch or
two above their nip.
When we use a sharper flux than grease for coating with tin or terne
metal, say rosin or chloride of zinc, we omit the soaking of the plates in
a preparatory pot of hot grease. If we use chloride of zinc we add a
little water to it occasionally if it becomes too dry, and from time to time
we strain and clean it. We make the upper pair of the coating rollers
on the entrance side of the coating pot about 8 inches in diameter. Above
and between the nip of these rollers we place a flux box about 10 inches
high, which we keep supplied with the rosin or chloride of zinc flux.
The metal into which the mouth of the flux box dips keeps the flux in the
flux box above the general level of the bath. We keep the nip of these
rollers well supplied with coating metal, and the nip pieces as described
in our Provisional Specification before mentioned are useful in this
‹ respect.

page_text: We also keep about 2 or 3 inches of coating metal at the bottom of
the bath, and from this supply, which is further fed by the droppings
from the rollers, we keep the coating rollers on the entrance side of the
bath supplied. Immediately below these 8 inch rollers are another pair
of coating rollers, of the same diameter. We make the upper pair of
such rollers revolve in troughs containing melted coating metal or flux,
as already described, and as the Drawings shew. The lower pair are fed
with coating metal which escapes downwards from the upper pair, but
if this is not sufficient we give them an additional supply by a gutter
from the pump or from a reservoir of fresh coating metal.
We shape the troughs so that there is a space of 4 or 5 inches of
melted metal or flux on the surface behind the rollers, and by a tool
shaped like a very small spade with an iron handle we are enabled to
keep the surface clean and free from scruff.
Hoop iron may be coated in a similar way to that shewn in Drawing
No. 2 by passing it between a series of coating rollers from the com-
mencement to the completion of the process, also wire if passed between
rollers with suitable grooves.
As already indicated the coating metal or flux which the plate gathers
in the first stages of coating may be of a quality less suited to give
finish and color to the plates than that contained in the troughs of the
after or finishing rollers. Thus we give the first coating of tin with tin
of a thicker or inferior character, and the after or finishing coating with
metal of better color, more liquid, or more free from impurity.
If coating with terne metal the mixture for the first coating may
contain rather less than one-third tin to two-thirds lead. In the
mixture for finishing or the after coating we use two-fifths tin and three-
fifths lead.
When using grease flux, that which we use in the flux box is thick
and stale, it acts more efficiently in causing the plates to take the coating
metal. That in the troughs which feed the rollers for finishing is more
fresh, or clean, or liquid.
If we use chloride of zinc in the early stages of the process for coating
with lead, tin, or terne metal, we pass all the plates through two coating
baths and leave them to stand ten or twelve hours in tanks of water
between the first and second baths (as described in the Specification of
Edmund Morewood's Patent of 4th February 1869, No. 349). .

page_text: If coating with spelter or zinc we use muriate of ammonia or sal
ammoniac as a flux mixed with the chloride of zinc, which sal
ammoniac or muriate of ammonia gather from the surface of melted
zinc when used as a flux upon it, and we refresh it with fresh sal
ammoniac and clean it from time to time.
When coating iron of heavy gauge or of such a nature as to take the
coating less readily we sometimes form a deeper trough of coating metal
by raising the nip pieces which we place between the ends of the rollers
to a level with the top of the coating rollers on the entrance side of the
bath, and we keep the trough thus formed supplied with coating metal
by a pump, as described, in our Provisional Specification, dated 23rd
day of March 1874, and to which under our present Patent we make no
claim. In such case the plates in process of coating pass through this
trough of melted metal on their way to the nip of the coating rollers
and immediately before reaching them.
We are aware that exit rollers by which plates are withdrawn from
baths of flux and passed from the nip of the rollers instantaneously into
the air have heretofore been supplied with coating metal by means more
or less imperfect. Such rollers are described in the Specification of a
Patent granted to Edmund Morewood, 14th January 1873, No. 123.
Our Invention does not consist in the use of such exit rollers as it is
essential to our method that a plate after coating metal has been applied
to its surface by rollers should travel for a considerable distance through
flux before emerging so that the flux may have time to act on and
repair the imperfections of the coating.
Whenever a plate is withdrawn from the coating bath whilst the
Leonting is imperfect the air acts unon it and forms a film which it is
1st. The process of coating iron or other metal sheets or surfaces with :
tin or other coating metal without previously immersing them in the
coating metal by applying melted coating metal to them as they enter
or travel beneath flux, the metal being applied by means of coating
rollers, which while revolving in contact with flux are fed and kept
constantly in contact with melted coating metal, substantially as
described.

page_text: 2nd. When coating iron or other metal sheets or surfaces with tin or
other coating metal, the application of melted coating metal to them as
they enter or travel beneath flux by means of coating rollers, which
while revolving in contact with flux are fed and kept constantly in
contact with melted coating metal, substantially as described.
3rd. When coating iron or other metal sheets or surfaces with tin or
other coating metal, passing them between rollers arranged in succession.
in a flux bath, when such rollers while revolving in contact with flux
are supplied respectively with coating metal of different qualities (either
originally so or from use), so that the best metal may be last brought
into contact with the sheet or surface, substantially as described.
In witness whereof, I, the said Edmund Morewood, have hereunto
set my hand and seal, this Twenty-fourth day of March, in the
year of our Lord One thousand eight hundred and seventy-
four.
EDMUND MOREWOOD. (L.S.)