Improvements in the Method of and Apparatus for Preparing Sheet Iron and Steel in the Manufacture of Tin and Terne Plates, or for Galvanizing.
Year: 1896

page_text: Date of Application, 28th Apr., 1896-Accepted, 30th May, 1896
COMPLETE SPECIFICATION.
Improvements in the Method of and Apparatus for Preparing
Sheet Iron and Steel in the Manufacture of Tin and Terne
Plates, or for Galvanizing.
I, JOHN DAVID GREY, of Tondu, near Bridgend, Glamorganshire, Manu-
facturer, 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 :-
This invention relates to improvements in the method of and apparatus for
preparing sheet iron and steel in the manufacture of tin and terne plates or for
galvanizing, the object of the invention being to dispense with the usual trouble-
some and costly process of black annealing, forming part of the treatment to which
sheet iron and steel, as hitherto prepared in the manufacture of such plates, has
been subjected, and generally to simplify the treatment of the sheet iron and steel,
with the view to turning out an increased quantity in less time and cost than at
present, and to attain an improved result.
I will firstly describe the process heretofore practised in the treatment of the
sheet iron or steel.
After the sheets have been rolled, and trimmed to the desired size in packs of
about eight sheets in each, and opened apart singly, they are pickled in a bath of
sulphuric acid diluted with water, for the purpose of reinoving the oxide or scales
from their surface, and after they have remained sufficiently long in such bath,
they are removed therefrom and placed into a tank of water, for the purpose of
cleansing them from any adhering acid. After such pickling process, the sheets,
while wet, are placed onto a cast iron stand and covered over with a cast or
wrought iron box, all then being placed into an annealing furnace, and generally
left to remain therein from ten to twelve hours, for the purpose of annealing and
cleansing the surface of the plates, preparatory to the cold-rolling process. The
process just described is called by the trade "black annealing," and is not only
objectionable on account of the rusting and uneven colouring of the plates, but is
also a very expensive operation, on account of the stands and boxes being very
soon burned, by the heat to which they are subjected in the annealing furnace, and
also by reason of the time and labour involved in carrying the plates through the
treatment.
Now, according to my improved method, instead of subjecting the pickled and
washed sheets to said black annealing process before cold-rolling them, as hitherto
practised, I effect the desired result by the much less troublesome, inexpensive and
more expedient means of subjecting them to a drying treatment in a drying oven
or stove situated intermediate of and in convenient relation respectively to the
washing tank and the cold-rolling mill, passing the sheets into said stove or oven
immediately after removing them from the washing tank, for the purpose of
immediately drying them to prevent them from oxidizing or becoming discoloured,
as they do in the black annealing process, and then passing them singly through

page_text: the cold-rolling mill immediately after they leave the oven, to smooth their
surface and close the pores thereof.
The improved combination of apparatus employed in carrying out said improved
method is represented, on the accompanying drawings in sectional elevation in
Fig. 1; Fig. 2, representing a transverse sectional elevation of the drying apparatus
on the line 1-1, Fig. 1.
The pickling, washing and rolling apparatus illustrated, are, respectively, of an
ordinary arrangement well known to those skilled in the manufacture to which the
invention relates, and, therefore, need not be described herein.
In carrying out the invention, I transfer each rack a, with its load of pickled and
washed sheets, from the washing bath b, directly and immediately to a carriage c
or the sheets can be transferred from the rack a, to a racked carriage c, placed
conveniently to the bath b, and to, and resting on rails d, running through, the
drying oven or stove e, which is or may be heated by gas or other fuel in fireplaces f,
or by hot air or otherwise in any convenient manner.
The carriages c, are then successively drawn slowly through the drying oven e,
by means of an endless chain g, to which they are detachably secured by hooks,
the chains being drawn. by sprocket wheels i, operated by steam or other con-
venient motive power, for the aforesaid purpose of drying them immediately after
they are taken from the washing tank. As each carriage c, emerges from the
drying oven, its hook h, is disconnected from the chain g, by one of the teeth of the
forward sprocket wheel striking against the lower side of the hook, throwing it up
and disconnecting it from the chain; whereupon, the carriage comes to a standstill,
adjacent to the rolling mill j, permitting of the sheets being immediately unloaded
from the carriage and passed through the mill, after which they are passed through
the white-annealing process and are finished in the ordinary way. The loaded
carriages c, may, however, be traversed through the oven e, by any other convenient
means.
I am enabled, by said improved method, to effect an economy of two days' time
in the process of manufacturing tin and terne plates, besides dispensing with said
costly and troublesome process of black annealing, and avoiding the disadvantages
attendant thereon, and, withal, obtain an improved product.
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 improved method of preparing sheet iron and steel in the manufacture of
tin and terne plates or for, galvanizing;-consisting in, pickling. and. washing the
sheets in a usual manner; immediately thereafter drying them in. an oven or stove
as hereinbefore described, in lieu of and, as distinguished from black-annealing
them and immediately thereafter cold-rolling them singly in a usual manner,
Preparatory to white-annealing and finishing them in a usual manner.
2. In said manufacture, subjecting the sheets to a drying treatment in an oven
or stove, in lieu of and, as distinguished from black-annealing them, subsequently
to pickling and washing them and previously to cold rolling them, and conducting
such operations in immediate succession, as described.
3. The improved apparatus for preparing sheet iron and steel in said. manu-
facture, consisting in the combination with a
cold-rolling mill, of a drying oven or stove placed intermediate of the pickling and
pickling and washing plant, and a
washing plant and the rolling mill, and in such relation thereto that the racks of
washed sheets or the latter can be immediately transferred from the washing bath
to carriages. arranged to traverse the drying oven, and slowly traversed through
the latter, and that the dried sheets, cap be singly transferred from the.carriages,
after having traversed the oven, to, the cold-rolling mill, as.set forth.
4. In apparatus employed, in, said manufacture, the employment of an oven
having rails extending through it, sprocket wheels arranged outside of the oven

page_text: and connected by an endless chain also passing through the oven, means for
actuating the sprocket wheels, and carriages for the sheets having hooks adapted
to connect the carriages to the chain and to be automatically disconnected
therefrom by the teeth of the sprocket wheels, as and for the purpose described.
Dated this 27th day of April 1896.
DAY, DAVIES & HUNT,
Chartered Patent Agents,
321, High Holborn, London, W.C., Agents for the Applicant..