The Indianapolis journal., 1891-06-24

PsnBsylvsnia's Second Mill in 0peraticn-How
Steel Is Covered with the Bright Mineral

Steel Is Covered with the Bright Mineral
Philadelphia Record.
1t is fact that the form of tin-plate
known as roofing plate is now made in
Philadelphia by taking imported steel-plate
of proper quality and coating it with
mixture of tin and lead. A mill near Front
and Laurel streets is turning ont every day
q score or more of boxes Of the
American roofing plate thus prepared.
This mill has been in opera
tion just two months. and, with the
exception of plant at Pittsburg, IL 10 tie
only one in Pennsylvanis, At the close OF
two months' operations the proprietors OF
the manufactory maintain that they can
produce first-class article of roofing TIM
plates as cheaply as they can be made In
England or Wales. plus the duty OF S44
ton. In other words, the consumer can
grade for as small q prIce as he can get the
British article. and pay the duty thereon
of Q rs oents. TO DO collected after July l,
1891. a...sas-
So far this mill has not attempted to pro-
duce bright tln. which is used for the man.
ufacture of tinware. However, the trm
has completed plans for the duplication OF
it's present plant, and still other additions
are anticipated. n. q u. lay ior Company,
Britain. and extensive importers, are max
ing an earnest test 20 determine definitely
whether or not they can hereafter make
their plates at home instead OF 5000 miles
away.
Tin-plate Is made of sheets of iron or
steel coated with pure tin, or mixture of
TIN and lead. When the sheets are covered
with pure tin the product ie called bright"
tin, and when the the coating 10 . mixture
of tin and lead the product is called roof
ing" tin. The value of both klnos depends
entirely upon the quality of iron
or steel used. the manner with
which the tin-plares are made and
the quality and quantity of the coating.
In making cheap tin plate Bessemer steel is
employed, and 10 coated by cheap process
acid being used as Q fux. and the plates
finally rolled to squeeze all the coating pos
sible of the steel, M leaving only enougn Ito TO
on the steel plates to make the coating
stick fast to it, or, as the Welsh say. to
make it "bite."
There are mills in England where rolls
are used which spread the coating OF tin SO
thinly upon the steel plates that ore pound
of the tin is sde TO cover one hundred
square feet of plate. This, OF course. is
w-grade article. As the steel costs but
pound there is general desire on the part
of manufacturers to put as little tin on the
plates as possible.
A 6rst-rste grade of bright" tin contains
ABOUT ten pOuQO6 Oh pure tln TO ONO nun
dred square feet of plate. This is put on
Siemens- Martin steel. An average OF six
and half pounds of tin to one hundred
square feet OF plate makes Q good article.
As lead costs but 4l2 cents pound. 1t 10
usually mixed in liberal quantities with the
tin to make tho coating metal. To be sure,
lead alone will not adhere to iron or steel.
and little tin Is absolutely necessary.
Tin-piates are usually made IN two sizes.
14x20 inches and 2OxS inches. They are
MAJ al in hnYa a
box of the best quality of bright tin. of the
l4x20 inches size sells for S11. A fair grade
sells for from $3.50 to 50. The steel before
it is coated 10 of two thicknesses. One size
is 14Il000 of an inch, and the other 10 $4,000.
The first is called the X and the second
tho G brand. On July the new tariff
duty of 22ll0 cents pound, or IA ton,
will 60 into effect.
new mill Of N. e. g. Taylor Company. near
Front aud Laurel streets, is an interestin nR
one. The company buys its steel plates in
England. The manner of converting them
ntO TIN is this, there being sixteen distinct
steps in the process:
/. The sheets of steel are cut into perfect
sizes by squaring machine.
2. From the squaring-machine the steel
is put into pickiing-box. This pickle
contains q good deal of sulphuric acid
and is applied for the purpose OF removi ng
rust.
3. Then the plates are lifted with swing
tongs from the pickiing-bOx into q trough
of water, where they are thoroughly
washed.
4. The next Is another water bath.
5. Then they are secured with sand to
remove the last particle of rust and to make
the plates bright and smooth.
d. A short distance away over q hot fur
mace are arranged six pots, the first OF
which contains boiling palm oil Into this
the steel plates are immersed.
Z. The second vat contains the mixture of
lead and tin metal. which is kept at the
boiling point, and here the plates get an
other bath.
s. A second pot of metal comes next, in
which the plates remain but q few minutes.
Q. The plates are then laid on tiL-cov-
cred table and both sides are vigorously
brushed with a heavy brush. This is to re-
move any little blisters that may have been
formed before the coating gets cold.
10. pot of metal similar to the other
mixtures is next. and into this hot plates
are swung
II. The plates are put in vat of boiling
II. Then they are dumped into pot of
metal once more and for the last time
Ii. One by one they 60 to bin of saw
dust and are rubbed on both sides.
II. Alongside of this is a bin of bran, and
here q boy again rubs the sides of the plate.
Is. The plates then go to q boy, who
sides thoroughly. This is the final touch
so far as the making OF tho tin is con-
cerned.
10. The plates 90 from the sheep-skins
to the stamping machine. Then they are
| packed into boxes and are ready for ship
ment.
From the time plate leaves the water
bath until it is stamped not more than
| twenty minutes elspse. The picking.
sand rubbing and washing processes do not
require nearly that long. The mills are run
| in SETS Each ''set" consists of the watts,
| pots, etc. mentioned above. To work
| them properly seven men and six boys are
| employed. Such q force turn out forty
| boxes of tIn-plates day. This is the ca
| pacity of the Tsylo mill.
Several new steel-plate mills are being
| built in this country. when it is expected
| the factories that make American tin will
| be able to purchase the black sheets at
more advantageous price than they can
now be gotten at from England. The
| greatest obstacle that is met with In man.
| ufacturing tin here is the scarcity of skilled
labOrers. 1t will require considerable
| time to educate home workmen up to tn 9
| point where they can hold their own with
Welshmen. who now operate early all the
tin-plate mills in existence.
Killed on the College Campus.