A New or Improved Process for Treating Steel Armour Plates.
Year: 1893

page_text: Date of Application, 15th Apr., 1893
Complete Specification Left, 15th Jan., 1894-Accepted, 17th Feb., 1894
PROVISIONAL SPECIFICATION.
A New or Improved Process for Treating Steel Armour Plates.
I, ALFRED LONGSDON, of 9 New Broad Street in the City of London Civil
Engineer do hereby declare the nature of this invention (a communication to me
from abroad by Louis Grambow of Rixdorf near Berlin in the Empire of Germany,
Merchant) to be as follows :--
This invention refers to a process for improving the quality of steel armour
plates consisting in the combination of the three following operations in the order
indicated.
1. Hardening the plates by immersing the whole plates in oil, water, or other
media, after having previously raised them to a temperature at which the molecules
have acquired the capability of ready re-arrangement.
2. Annealing the plates at a temperature which is as high as possible without
however reaching the temperature at which said capability of ready re-arrangement
begins.
3. Hardening the plates on one side or face at the same or at a lower
temperature than that specified in the preceding or second operation.
In order to avoid great deviations from the form desired to be given to the plates
through the last of the three above named combined operations, that is through
the hardening of the side exposed to the projectile, the present invention consists in
interposing between the second operation of annealing and the last operation a
further new operation namely the hardening of the dead or false side of the plate
not exposed to the projectile. For this hardening the annealing heat may
be used.
By this interposed operation, the hardening effect of which is nullified or
destroyed by the heating of the last operation, the plate undergoes an alteration of
form which is counteracted by or opposite to the alteration of form produced by or
resulting from the last hardening by which the side or face exposed to projectiles
is hardened so that the form of the finished hardened plate corresponds with the
form before the commencement of the operations.
For the same purpose the process may be carried out also in a simplified manner,
consisting in substituting the first operation of chilling the whole mass of the
plates, by chilling only the side or face of the plate, which is not to be exposed to
projectiles then glowing the whole mass of the plate and finally hardening by
chilling the side or face of the plate which is to be exposed to projectiles.
By the subsequent hardening of both sides of the plate and by the intervening
reheating between the two hardening operations exactly the same properties are
given in the case of thinner plates, to the main mass of the latter, while the central
layer of the metal of very thick plates does not receive these excellent properties
in a quite perfect degree.
By this invention I provide a process for the one side hardening of armour plates
consisting in that the plates are in the first place hardened throughout their entire
mass by chilling, then annealed in their entire mass, then hardening the side not
exposed to the action of the projectile, and finally after reheating again hardening
by chilling the side or face to be exposed to projectiles; or hardening armour
plates on one side consisting in that the plates are first hardened by chilling upon

page_text: the side not exposed to the action of projectiles, then annealed in their entire mass
and finally hardening again by chilling the plates on the exposed side.
Dated this 15th dow of Anvil 1002
BREWER & SON,
London and Leeds, Agents for Applicant.
COMPLETE SPECIFICATION.
A New or Improved Process for Treating Steel Armour Plates.
I, ALFRED LONGSDON, of 9 New Broad Street, in the City of London, Civil
Engineer, do hereby declare the nature of this invention (a communication to me
from abroad by Louis Grambow of Rixdorf near Berlin in the Empire of
Germany, Merchant) and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
This invention refers to a process for improving the quality of steel armour
plates, consisting in the combination of the three following operations, in the order
indicated.
1. Hardening the plates by immersing the whole plates in oil, water, or other
media, after having previously raised them to a temperature at which the molecules
have acquired the capability of ready re-arrangement.
2. Annealing the plates at a temperature which is as high as possible, without
however reaching the temperature at which said capability of ready re-arrangement
begins.
3. Hardening the plates on one side or face at the same or at a lower
temperature than that specified in the preceding or second operation.
In order to avoid great deviations from the form desired to be given to the
plates through the last of the three above named combined operations, that is
through the hardening of the side exposed to the projectile, the present invention
consists in interposing between the second operation of annealing, and the last
operation, a further new operation, namely the hardening of the dead or false side
of the plate, not exposed to the projectile. For this hardening the annealing heat
may be used.
By this interposed operation, the hardening effect of which is nullified or
destroyed by the heating of the last operation, the plate undergoes an alteration of
form which is counteracted by or opposite to the alteration of form produced
by, or resulting from the last hardening, by which the side or face exposed to
projectiles is hardened, so that the form of the finished hardened plate corresponds
with the form, before the commencement of the operations.
For the same purpose the process may be carried out also in a simplified manner,
consisting in substituting the first operation of chilling the whole mass of the
plates, by chilling only the side or face of the plate, which is not to be exposed to
projectiles, then glowing the whole mass of the plate, and finally hardening by
chilling the side or face of the plate which is to be exposed to projectiles.
By the subsequent hardening of both sides of the plate and by the intervening
re-heating, between the two hardening operations, exactly the same properties are
given in the case of thinner plates, to the main mass of the latter, while the central
layer of the metal of very thick plates does not receive these excellent properties
in quite a perfect degree.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what
I claim is :-
:-
1. The new or improved process for hardening armour plates on one side or face,
consisting in that the plates are in the first place hardened throughout their entire
mass by chilling, then annealed in their entire mass, then hardening the side not

page_text: exposed to the action of the projectile, and finally after reheating, again hardening
by chilling the side or face to be exposed to projectiles, substantially as and for the
purposes set forth.
2. The new or improved process for hardening armour plates on one side,
consisting in hardening them by chilling upon the side or face not exposed to the
action of projectiles, then annealing the whole body of the plates in their entire
mass, and finally hardening again by chilling the plates on the side exposed to
projectiles, all substantially as and for the purposes set forth.
Dated this 15th day of January 1894.
BREWER & SON,
London and Leeds, Agents for Applicant.