Process for Coating Metals with Tin.
Year: 1894

page_text: Date of Application, 20th Oct., 1894
Complete Specification Left, 16th Mar., 1895-Accepted, 4th May, 1895
Process for Coating Metals with Tin.
I, LOUIS BANGERT, of 66 Movenstrasse, Libau, Russia, do hereby declare the
nature of this invention to be as follows:-
-:
My invention relates to an improved process for coating metals with tin which
is carried out as follows.
A vessel containing molten tin is divided into three compartments. The first
and second compartments are separated from each other by a partition reaching
down from the top to a certain distance into the molten metal, leaving the two
compartments in communication with each other at bottom.
In the first compartment the tin is covered with a layer of chloride of zinc, and
in the second with a mixture of oils, the partition having the object of keeping the
chloride of zinc and the oil separate from each other. The third compartment
contains pure tin covered with the oil mixture.
The oil mixture consists preferably of from 45 to 50 p.c. of palm oil and
50 to 55 p.c. of mineral oil, such as naphtha.
The metal sheets after pickling in. dilute sulphuric acid, are introduced wet into
the tin bath, and by a suitable device are brought under the partition from the
first to the second compartment, through which it is raised up. It is then seized
by a pair of tongs and immersed into the third compartment.
After withdrawal from this, the sheet is then passed through a vessel filled with
the above named oil mixture, in which are a series of revolving pairs of rollers
by means of which the sheets are carried through the bath. The plates after
leaving this bath are lastly scoured with bran. In the ordinary timing process
with brushes, the pickled plates are boiled in oil or tallow and are then passed
through the tin bath, and after removal therefrom they are brushed for removing
the oxide of tin and dirt. In this process the metal sheets are subject to oxidation
and a great loss of tin is caused by the brushing operation. By the use of the
above described improved process this loss is avoided, so that a saving of at least
1 lb. of tin is effected in a box of 112 sheets measuring 14 in. x 20 in.
The oil vessel contains by preference five pairs of rollers of which two pairs are
situated one above the other, and there is a suitable lever arrangement for guiding
the plates into the lowest rollers.
By the use of the above described oil mixture a remarkably pure tinned
surface of great lustre is obtained, such as is not attainable by any other process.
Dated this 20th day of October 1891
ABEL & IMRAY,
Agents for the Applicant.

page_text: I, LOUIS BANGERT, of 66 Movenstrasse, Libau, Russia, 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 :-
My invention relates to an improved process for coating metals with tin
which I will describe with reference to the accompanying drawings in which
Fig. 1 shews a longitudinal section of the apparatus employed for carrying out
the process as applied to the tinning of iron sheets, Fig. 2 shows a plan and Fig. 3
a cross section on line X X Fig. 1.
The apparatus consists firstly of the tinning tank A, secondly the oil tank with
squeezing rollers B, and thirdly the water tank C. The tinning tank is divided
into three compartments 1, 2 and 3, of which Nos. 1 and 2 are only divided at
the upper part by a partition which extends downwards about 12 inches from the
top of the tank and dips about 6 inches into the molten tin, below which point the
two compartments communicate.
In the first compartment the tin is covered with zinc chloride, and in the second
one with a special mixture of oils to be presently described, the object of the
partition being to keep the zinc chloride and oil mixture separate from each
other.
In compartment No. 1 is a lever device a for bending the metal sheets to be
tinned that descends through the first compartment, past the under edge of the
partition into the second compartment. No. 1 also contains a lifting device b, for
raising the sheets up through the compartment No. 2. Compartment No. 3 is
entirely separated from Nos. 1 and 2 by a partition and contains pure tin covered
with the said oil mixture.
The oil bath B which is filled with the said oil mixture contains five rollers, of
which two pairs ele², e³ e, are arranged vertically one above the other and serve
to squeeze the superfluous material from the sheets as they pass through them.
The fifth roller e serves to clear the upper pair of rollers. The bath B also
contains a lever device for bending and raising the sheets between the pairs of
rollers.
The water tank C serves as a receptacle for the pickled iron sheets previous to
the tinning and is simply filled with water.
The process. is carried out as follows. The operator first takes the plates
previously pickled in dilute sulphuric acid one by one from the vessel Cand
immerses them in the compartment No. 1 of tank A, through the zinc chloride
covering the lever a is then moved over to the left so as to bring the immersed
sheet past the lower edge of the partition into compartment No. 2. A second
operator then moves the lever b to the right and thereby raises up the tinned
sheet up out of compartment No. 2, and seizing the sheet by a pair of tongs he
immerses it into the compartment No. 3, after which he introduces it into the oil
bath B. A third workman then operates the lever f of this bath so as to raise
the sheet up through the pairs of rullers, and the finished tinned sheet is then
placed upon a table on which it is scoured with bran for removing the oil.
The above mentioned mixture of oils employed in this process consists of about
25 parts of palm oil, 25 parts of tallow, and about 55 parts of mineral oil such as
naphtha; it has the advantage over the use of palm oil or tallow alone, that by
means thereof a remarkably pure tinned surface of great lustre is obtained, while
the mineral oil employed costs only about one fourth as much as the other oils.
The above described tinning process differs from those heretofore generally
used, in that the pickled plates are not first boiled in oil or tallow before being

page_text: dipped in the tin bath, nor are they scrubbed with brushes on removal therefrom
for removal of scum and dirt.
As in these processes the tinned sheets are subject to oxidation before the
tinning is complete, a considerable loss of time results, which is entirely avoided
with my process, so that with the latter a saving of from 25 to 30 per cent. of
tin is effected.
My process has also the advantage over the more recent processes in which the
scrubbing. with brushes is done away with, that a much more brilliant and pure
tinned surface is obtained.
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. The herein described process of tinning sheet metal, wherein the sheets are
first passed down through a compartment of the tinning bath containing tin covered
with zinc chloride, are then passed from the lower part of this compartment up
through a second compartment in which the tin is covered by an oil mixture, and
after being again dipped in a third compartment containing tin covered with the oil
compound, the sheets are lastly immersed in a bath of the oil compound in which
they are passed through pressing rollers, the pickled sheets being stored in a tank
of water before being subjected to the said tinuing process.
2. The use for tinning processes, of an oil compound consisting of about
25 parts of palm oil, 25 parts of tallow, and 55 parts of mineral oil such as
naphtha.
Dated this 16th day of March 1895.
ABEL & IMRAY,
Agents for the Applicant.