IMPROVEMENTS IN COATING METALS AND IN APPARATUS EMPLOYED THEREIN
Year: 1879

page_text: LETTERS PATENT to Edmund Morewood, of Llanelly, in the County of
Caermarthen, Tin Plate Manufacturer, for the Invention of "IMPROVEMENTS
IN COATING METALS AND IN APPARATUS EMPLOYED THEREIN."
PROVISIONAL SPECIFICATION left by the said Edmund Morewood at the
Office of the Commissioners of Patents on the 26th September 1879.
EDMUND MOREWOOD, of Llanelly, in the County of Caermarthen, Tin Plate
Manufacturer. "IMPROVEMENTS IN COATING METALS AND IN APPARATUS EMPLOYED
THEREIN."
According to my Patent, No. 123, January 14th, 1863, amended by Disclaimer,
which was filed the 13th July 1869, I describe the use of a pair of stationary
guides for guiding the plates or sheets of iron or other metal in the process of
coating under the melted coating metal or flux from the entrance side of the pot or
vessel containing the flux or coating metal to the exit or finishing side, or to the
withdrawing rollers which revolve in contact with finishing flux or metal.
I there describe the use of guides when coating and finishing plates or sheets of
iron with other metal, by passing the plates through melted coating metal or flux,
contained in two or more pots arranged for the purpose of coating such sheets or .
plates of iron with other melted metal in more than one operation.
Now the object of my present Invention is to enable me to pass through more
work in a given time, or to do it with less labour or more soundly, or with a smaller
quantity of melted metal in use in the coating process at one time. And for this
purpose I so arrange a guide or guides in connection with the other machinery or
apparatus, of a pot or vessel containing melted metal and flux for the purpose of
coating, and what is termed finishing in one operation, that each sheet or plate in
process of coating shall have the opportunity of standing, dwelling, or staying
awhile under the flux or melted coating metal, or of occupying so long a time in
passing under the melted coating metal or flux, that when the sheet or plate in
process of coating leaves the finishing flux, or the finishing or withdrawing rollers
on the exit side of this apparatus or pot, a sound coating has been completed in one

page_text: operation, whilst using a flux of tallow, rosin, grease, or other matter which has
not the injurious tendency (in the coating of tin or terne plates), which fluxes of
metallic salts, such as chloride of zinc, when used on the entrance side of such
coating pot or apparatus have.
For this purpose I place guides so as to form two or more confined roads or lines
of travel for the sheets or plates of iron or other metal, when passing under the
melted coating metal or entrance flux in the process of coating.
And in practice I work so that when one sheet or plate is entering or laying
under the entrance flux or melted coating metal between guides forming one road
or confined line of travel, another sheet or plate is travelling out under or through
the coating metal, or into the finishing flux or finishing rollers, by another road
formed by means of other guides making another confined line of travel.
I find it important to shape or arrange the guide so that the sheet or plate in
process of coating, travelling along either or any of the confined roads formed by
such guides, will pass readily from such road or guide into and between the nip of
the same pair of withdrawing or finishing rollers.
Sometimes, especially when I wish to coat sheets or plates of comparatively
small size, as 20 + 14, I make use of shorter guiding or holding or carrying
instruments.
I arrange this shorter guiding or carrying instrument so that it can rise or
stand in or in contact with the flux on the entrance side of the pot or apparatus, or
be held back in or in contact with the coating metal such length of time as may be
desirable, and so that the plate can be deposited in or between it, or be held by
it whilst it is in contact with such entrance flux, and so that it can start therefrom
and travel thence to such a position as to place or introduce the plate it carries into
the nips of the withdrawing or finishing rollers. And I arrange in practice more
than one parallel line of road or travel for these short guides, so that one may be
travelling whilst another is loading, or standing, or delivering, or returning.
Such guiding, holding, or carrying instruments being comparatively short, have
to travel a portion of the distance between the entrance and the exit side of the
coating and finishing single pot under the melted coating metal or flux.
In practice I cause them to travel by a swinging movement, or by an endless
chain or other convenient arrangement, and to present the plate or sheet held or
contained therein to the finishing or withdrawing rollers revolving at or near the
exit side of this single pot or apparatus, so that such rollers can readily receive the
plate squarely and evenly, and pass it on to other rollers or out of the coating
metal or flux.
And I so make and arrange these carrying guides or instruments that the plates
can be readily placed or introduced therein, and so that when they arrive at the
proper distance from the withdrawing or finishing rollers, they are in a position to
enter evenly and squarely between them.
I make the guides or holding instruments, whether stationary or carrying, by
preference of cast iron or of steel.
I also make the rollers in the body of the melted coating metal of that
material.
The bottomless pot or compartment containing the finishing flux, and in which
I find it desirable to keep one or more pair of finishing rollers working, is so
arranged that a portion of such finishing flux and rollers sits or rests over or upon
or against the melted coating metal on the exit side.
And I find it desirable that the plates in process of coating should pass from the
melted coating metal into and through the rollers or finishing flux by the aid of
guiding instruments.
I find it well to arrange the finishing grease bath with barriers or air spaces, to
check the heat rising up from or communicated by the surface of the melted coating
metal, or imparted by the plates as they enter hot from the coating metal.
They also assist by suitable arrangements in heating up when the grease is.
too cool.

page_text: I also attach to this finishing pot or compartment, an end or ends which project
beyond the surface of the coating metal, so that the flux contained in such end or
ends rests upon a floor or bottom other than that of the melted coating metal, and
can consequently be kept comparatively cool, and be maintained at a temperature
different from that of the flux which rests on or against or is over the surface of
the melted coating metal.
Such flooring also forms a convenient rest for the deposit of scruff, dirt, or
settlings which are constantly being introduced into or forming in the hot
grease.
Scruff and dirt are introduced into the hot finishing grease by the plates in
process of coating rising up into it from the melted coating metal.
They also communicate to such finishing grease a portion of the heat which they
bring with them from the melted coating metal.
And as they travel up through such finishing grease, they keep it in a state of
motion and agitation, so that the scruff, dirt, and settlings seek rest in the quiet
and undisturbed end or ends of such finishing grease pot or compartment.
I also furnish such finishing grease pot with arrangements for the inflow and
outflow of grease, so as to enable me, when desirable, to have a circulation, and to
regulate the temper and quality of such finishing grease.
Further, I furnish such finishing rollers with troughs or supply arrangements
for giving such rollers a suitable supply of fresh coating metal and washing their
surface.
The end or ends of the finishing grease compartment containing a reservoir of
cool grease, assist in regulating the temperature of that part which is heated by
the travel of the hot plates from the coating metal, also by sitting on the melted
metal, and further by any heat from the arrangements for supplying fresh melted
metal to the finishing roller.
In some cases I cause the plates to pass from the metal compartment of the
coating pot into the compartment containing the grease or flux by a comparatively
narrow channel or spout, entering the finishing compartment at the side, and curved
or inclined upwards so that the mouth of the channel or spout is directed towards
the nip of the finishing rollers revolving in the finishing grease or flux. It is thus
only at the mouth of the spout or channel that the melted metal of the coating
compartment is in contact with the grease or flux, and hence this arrangement
affords great facility for regulating the temperature of the grease or flux in the
finishing compartment independently of that of the coating metal in the coating
compartment.
Also as the coating metal in the spout or channel is confined in a comparatively
narrow space, the arrangement affords facility for regulating the temperature of
this metal, which is near the point where the plates pass into the finishing flux or
grease, independently to a great extent of the temperature of the coating metal in
other parts of the coating compartment. In this way I am better able to ensure
the plates being sufficiently cooled before they reach the finishing grease or flux.
I find it advantageous to provide space in the finishing compartment beneath the
level at which the spout or channel above mentioned enters. This space receives
the drippings of coating metal from off the finishing rollers, and in it also any
impurities which may find their way into the finishing compartment will settle
down.
I also find it desirable to use a worm wheel to give motion to the rollers between
which the plates pass up through the finishing grease.
Such worm wheels give a steady and even motion to a series of pairs of rollers,
and in practise I find it desirable to use four or five finishing pairs of rollers in the
finishing grease.
Such worm wheel may be raised or depressed by means of a spring lever or elastic
matter connected therewith.
Or the bearings in which the necks of the rollers revolve may be connected with
a lever or spring or elastic matter.

page_text: If the worm is at such a temperature that fluid coating or finishing metal would
set upon it, I place it at such a distance from the fluid or melted metal that it will
be out of reach of splashing or overflowing of such fluid metal.
By preference, I place the worm and worm wheels which drive the rollers
revolving in the finishing grease outside such finishing grease.
I sometimes impart motion to the rollers by a crank or connecting rod.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edmund Morewood in the Great Seal Patent Office on the 25th
March 1880.
EDMUND MOREWOOD, of Llanelly, in the County of Caermarthen, Tin Plate
Manufacturer. "IMPROVEMENTS IN COATING METALS AND IN APPARATUS EMPLOYED
THEREIN."
"
This Invention has for its object to coat plates and sheets with tin or terne metal
or like alloy at one operation better and more expeditiously and economically than
by means hitherto employed or proposed. The coating is effected, as heretofore, by
passing the plate or sheet through flux into melted coating metal heated to a
sufficiently high temperature; and the plate or sheet is finished, as heretofore, by
passing it into grease and withdrawing it between rollers. Now in order to
prevent the grease becoming too highly heated, even when plates or sheets are
passed in rapid succession through the apparatus, and to admit of the temperature
of the grease being regulated independently of that of the coating metal, I cause
the plates or sheets in passing from the hot coating metal towards the grease to
traverse a cooling channel or "spout" leading out from the compartment of the
apparatus in which the hot coating metal is contained. This cooling channel or
spout" opens by a narrow mouth into the compartment containing the grease, so
that the grease is in contact with the molten inetal of the coating compartment
only at the narrow mouth in which the cooling channel or "spout" terminates,
and here also the coating metal is at a much lower temperature than it is where
the coating takes place, in consequence of the sides or walls of the cooling channel
or "spout" being cooled by radiation and by air currents or otherwise. The plates
or sheets passing through the apparatus also loose in great measure the high
temperature which they acquire in the coating part of the pot or apparatus as they
pass through the cooling channel or "spout" and before entering the grease. Thus
they carry forward to the grease much less heat than they otherwise would do, and
consequently the work may be carried on rapidly without the grease becoming
overheated. I also cause the grease compartment of the apparatus to extend below
the mouth of the cooling channel or "spout," and I so provide a space or pocket
where the grease may be comparatively at rest and undisturbed by the passage of
the plates or sheets, and in which it may deposit impurities. This pocket also
receives the metal which drips from the rollers, and a trap is provided by which

page_text: this can be ladled out. The pocket also increases the area of the sides of the grease
compartment, available for cooling and regulating the temperature of this part of
the apparatus.
The pot containing the coating metal has a curved bottom and flat parallel sides.
The cooling channel or "spout" is produced by fixing hollow barriers across the
pot, confining the molten metal on the exit side of the pot to a narrow passage.
The plates to be coated are carried, into the pot by carriers, which are caused to pass
down with the plates through the flux into the coating metal. The carrier and
plate pass on together until the leading edge of the plate reaches the rollers in the
grease compartment, and these rollers have their axes at right angles to the plane
in which the carriers travel, so that the plate is presented fairly to their nip. The
rollers seize the plate and take it out of the carrier, which then goes back to have
another plate put into it. Sometimes I mount the carriers upon curved arms,
which are caused by racks or cams or in other convenient way to rock about an
horizontal axis concentric or nearly so with the bottom of the pot containing the
coating metal.
When the pot is wide two or three carriers may be fixed upon one pair of arms,
to pass several plates simultaneously through the apparatus. Or in place of
mounting the carriers upon curved arms they may be carried upon endless chains
or steel bands contained within the pot.
In order to impart to the withdrawing rollers a smoother motion than can be
obtained when they are driven by means of spur wheels, which is the usual method
of driving such such rollers, I connect the axis or neck of one roller of each pair by
a crank arm with a rod which receives vertical and lateral movements from two
driving cranks on separate axes.
Or in some cases I prolong the neck of one roller of each pair through the end of
the grease compartment of the apparatus, and mount worm wheels on these necks
to gear with worms on an upright driving axis, and to give smoothness to tho
action of the driving gear I so mount the worms that they can slide on the driving
shaft, which nevertheless by a feather or like arrangement carries them round with
it. I apply strong springs to hold the worms in their places on the shaft, and
these springs yield when at work to the slight extent necessary to prevent jolts
being imparted to the rollers by the driving mechanism.
In order that my said Invention may be most fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed,
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a vertical section of coating apparatus constructed according to my
Invention; a, a, is a round bottomed pot with flat ends, when in use it is filled
with the coating metal about to the line a', al; b, b, are hollow barriers passing
from side to side of the pot, they serve to confine the the metal on the exit side of
the pot to a somewhat narrow channel or "spout.” The pot is heated by a fire
beneath, as is usual, and the fire place is constructed at the entrance side of the pot,
and does not, when the apparatus is at work, play beneath the pot on the exit side.
On the contrary beneath the pot on the exit side flues are or may be constructed,
through which cold air can be allowed to pass in order to cool to the desired extent
this part of the pot and the coating metal contained within the cooling channel or
spout." Cold air can also be passed through the hollow barriers b, b, with a like
object, and even, if need be, they may be cooled by the careful application of a
varifying spray of water. Nevertheless, for heating up the apparatus I cause
heated air from the main fire or from a separate fire to pass through the flues
beneath the pot on the exit side, and also it may be through the barriers b, b, and
through flues formed against the grease compartment c; the grease compartment c
is mounted over the mouth of the cooling channel or "spout," and the metal in the
channel or "spout" supports the grease, but being only in contact with it over the
small area exposed at the mouth, and the metal in the "spout" being comparatively
«

page_text: The
cool, the amount of heat imparted from the metal in the pot to the grease is not
such as to cause inconvenience, or to prevent the grease being kept at the
temperature best suited for finishing the coating upon the plates or sheets.
grease compartment c is made to descend below the mouth of the "spout" by which
the plates or sheets enter, so that at c' there is a pocket which receives the
drippings and scruff from the metal, and in which any impurities in the grease can
settle, as the grease here is but little disturbed by the passage of the plates. The
surface also exposed by this extension of the grease compartment facilitates
the regulation of the temperature of the grease; d, d, are tinned or coated rollers
within the grease compartinent, they are such as are now commonly employed in
finishing tin and terne plates. The necks of the rollers are held in bearings in the
frames d¹, d', and the rollers of each pair are held together by springs adjustable by
screws, as shown, and as is usual.
The rollers are geared together in pairs at one end by toothed pinions, and at the
other end the axis or neck of one roller of each pair is continued through bushed
holes in the holes in the end of the grease compartment, and they have small worm
wheels fixed upon them. For the purpose of driving the rollers d at the proper
speed for delivering the plates there is a vertical axis e with a bevilled wheel at its
upper end, gearing with a similar wheel on the horizontal driving shaft f. The
axis e carries a series of worms for driving the several worm wheels on the necks
of the rollers, and these worms, as already mentioned, whilst revolving with their
axis can slide upon it for a short distance; each worm has a strong spiral or disc
spring on either side of it, and these springs are held compressed by nuts screwed
upon the axis.
Figure 2 represents a plan of the grease compartment, and Figure 3 is a front!
view of the same.
The grease will not be found to escape to any material extent from the bushed
holes by which the necks of the rollers pass through the end of the grease compart-
ment, what does escape is collected by a trough which delivers it into a receiver.
A little packing may be applied around the necks of the rollers should any
inconvenience be experienced from the escape of the grease.
It will be observed that at the ends of the compartment beyond the bearings of
the rollers there are spaces of considerable dimensions where the grease is com-
paratively at rest, and is able to cool and settle. In order to isolate the ends to a
great extent from the other parts of the grease compartment, they are supplied
with bottom plates dropped in at about the level of the bottom of the bearing
frames below the lowest rollers. The metal dropping from the rollers flows beneath
one of these bottom plates to the opening or trap at c*, in which the metal stands
supporting the head of grease in the grease compartment; as the metal accumulates
it is removed with a ladle from time to time, or it may be allowed to run over into
a receptacle.
From one of the ends of the grease compartment when the apparatus is at work
a boy ladles the grease and pours it at the back of the uppermost pair of delivery
rollers d. Underneath this pair of rollers, and also beneath the pair of rollers
immediately below, troughs are arranged to contain melted tin or coating metal, so
that these rollers may be immersed in metal nearly up to their nip, and fresh clean
metal is supplied to these troughs with a ladle from time to time. The grease
compartment is kept filled with grease aboat to the line of the nip of the upper-
most rollers d, either a little above or a little below it, according to the appearance
it is desired to give to the plates. g is a flux box on the entrance side containing
the grease or flux through which the plates or sheets are passed on their way into
the coating metal; h is an horizontal axis on which the arms i, i, are mounted, so
that they are able to rock; k, k, are the plate carriers supported by the arms i, i, at
their outer ends. The Figures 4 and 5 show one of these carriers to a larger scale.
The carrier consists of two grids formed of light rods. The grids are fixed together 5
one in front of the other, leaving just the space between them which will admit of a
plate being inserted. The plate is put in from the top between the two grids when

page_text: the carrier is in the position of that shewn on the entrance side of the pot in
Figure 1. The grids being somewhat curved the plate becomes slightly bent when
it is placed between them, and the spring of the plate is sufficient to cause it to
press against the grids with as much force as is necessary to prevent the plate
falling out of the plate holder. The rods of which the outer grid is formed have
latch like heads k¹, k¹, which catch upon the upper edge of the plate when it is
inserted into the carrier, so that the plate may not be displaced in the carrier when
its leading edge is presented to the nip of the undermost pair of rollers d. In the
arrangement shown at Figure 1 there are three pairs of carrier arms, and on each
pair a set of plate carriers is fixed. The pot may be sufficiently wide to admit of
three carriers to form a set being placed side by side, allowing about a two inch
space between the edge of one plate and the next when the plates are in the
carriers, so that there may be no risk of the plates interfering the one with the other
as they pass up between the rollers d. The arins are also so formed or guided that
the carriers of the different sets may pass each other without collision. The carrier
arms, as represented in the Drawings, receive their movements from racks gearing
with spaced wheels on a driving shaft, and they are brought back by counterpoise
weights, but the carrier arms may if preferred be actuated and controled by cams
or otherwise. It is desirable that the carriers should travel slowly as they approach
the delivery rollers, so that the edge of the plate may be entered quietly between
the rollers, and there should be a dwell also at the time that the plate is introduced
into the holder. The return motion of the holder may also be more rapid than its
forward movement to avoid loss of time. The curved arms carrying the plate
holders may be thus controled by various well known mechanical means. Plate
carriers of this description and delivering to rollers in the manner described may be
employed in some cases where from the nature of the coating metal it is not necessary
or desirable to finish the plates through grease.
Figure 6 is a plan of an arrangement in which the plate carriers are hung upon
pivots on either side from two endless chains or metal bands 6, 1. The bands pass
around guide pulleys, as is shewn, and the pulleys at the lower extremity of the
course of the bands or chains are upon an axis within the pot, which is driven by
bevelled gear, as the Drawing indicates. m, m, are guide rods within the pot;
upon these the plate carriers are supported as they travel round; n is a guard to
protect the chains or bands and carriers from cooling influences as far as possible.
In Figure 6 is also shewn the way in which is actuated the delivery rollers d, d,
by means of cranks; o is a vertical rod jointed to crank arins upon the necks of one
roller of each pair; this rod receives a vertical movement from the driving crank o¹,
and a lateral movement from the auxiliary driving crank p, and in this way the
rollers d are very smoothly driven.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I claim my improvements in
coating metals and in apparatus employed therein substantially as described, that
is to say, I claim,-
First. My improvement in the process of coating sheets and plates with tin or
terne metal or like alloy, consisting in causing the plate or sheet to pass from a
compartment containing the coating metal at the temperature required for coating
into a compartment containing grease through a cooling channel or spout having a
narrow mouth where the grease rests upon the coating metal, by which means the
excessive transmission of heat from the melted coating metal to the grease is
avoided.
Second. My improved apparatus for coating plates and sheets with tin or terne
metal or like alloy, consisting of a pot containing the coating metal, and barriers on
the exit side of the pot confining the coating metal within a cooling channel or
spout terminating in a narrow mouth, over which there is a compartment containing

page_text: grease, and having rollers by which the plates or sheets are carried upwards through
the grease and delivered.
Third. The formation of the grease compartment with a pocket or space below
the level at which the cooling channel or spout enters it, such pocket or space
serving to receive the metal drippings, and being otherwise useful, as previously
explained.
Fourth. The arrangement for carrying the plates through the coating apparatus,
consisting of plate carriers propelled with the plates through the coating metal, and
presenting the plates to rollers having their axes perpendicular to the plane in which
the carriers travel, and by which rollers the plates are raised and delivered whilst
the carriers are drawn back to receive other plates, and so on.
Fifth. The method of driving the series of rollers between which the plates or
sheets pass by means of cranks.
Sixth. The method of driving the series of rollers between which the plates or
sheets pass by means of worm wheels on the necks of the rollers, and worms
gearing with these worm wheels, such worm wheels and worms being exterior of
the grease containing compartment, within which the rollers are situate.
Seventh. The apparatus for coating metals, substantially as described and repre-
sented in the annexed Drawings.
In witness whereof, I, the said Edmund Morewood, have hereunto set my
hand and seal, this Twenty fifth day of March, in the year of our Lord One
thousand eight hundred and eighty.
EDMUND MOREWOOD. (LS.)