IMPROVEMENTS IN BESSEMER CONVERTER AND FURNACE LININGS."
Year: 1881

page_text: LETTERS PATENT to David Evans and Alexander Edwin Tucker, both of
Rhymney Iron and Steel Works, South Wales, for an Invention of
"IMPROVEMENTS IN BESSEMER CONVERTER AND FURNACE LININGS."
PROVISIONAL SPECIFICATION left by the said David Evans and Alexander
Edwin Tucker at the Office of the Commissioners of Patents on the 17th June
1881.
"
DAVID EVANS and ALEXANDER EDWIN TUCKER, both of Rhymney Iron and
Steel Works, South Wales. 'IMPROVEMENTS IN BESSEMER ČONVERTER AND
FURNACE LININGS."
This Invention relates especially to the manufacture of Bessemer tuyeres and
bottoms. Hitherto it has been the practice to manufacture Bessemer tuyeres and
bottoms of the material known as ganister, a material consisting principally of
silica with just sufficient quantity of clay to form a plastic mass when treated with
water, which when moulded into the required form is air dried or burnt in an
ordinary kiln. The tuyeres are imbedded in ganister made plastic with water;"
the whole is then well dried and constitutes the complete bottom of the Bessemer
converter. This method has the following disadvantages:-1st. It is difficult to
thoroughly dry the mass, and on being exposed to the intense heat generated in
the converter steam forms, thus disintegrating the bottom and causing it to wear
out very quickly. 2nd. The ganister particles are not firmly bound or fused
together, consequently the bottom cannot well resist the abrasive action of the
blast blown in and the action of the agitated molten metal. From these causes
and the comparatively fusible character of the material used a large quantity of
silica is mixed up with the fluid metal, thereby delaying the complete conversion
of the crude iron into steel, and seriously affecting the quality and yield of the
finished product. The object of our Invention is to remedy these defects, and we
do this as follows:-We take the ordinary ground ganister or other similar
material, free from water, and mix it with a proper proportion of the residuum, or

page_text: the crude ends of heavy oils, preferably those distilled from minerals (such as coal
tar), substances capable of forming a plastic mass with ground ganister or other
material used, using such proportions of both as may be found best in practice or
suitable to the quality of the iron converted and the steel made. Also varying the
proportions of the residua, such as coal tar, in the material used for forming the
bottoms, and such proportions as may be best for the manufacture of tuyeres
alone, in accordance with the requirements of the crude metal used and the steel
inade. The tuyeres are moulded in the usual manner and are then either air dried
or heated in a properly constructed kiln or by any other convenient method,
thereby forming hard dense tuyeres free from water, and more capable of resisting
abrasion and chemical action than ordinary tuyores. The complete bottom is
formed in the usual manner, but using the mixture of ganister or other similar
material and the residue of heavy oils (such as coal tar) and is dried in the ordinary
way with a further exposure to heat, ns during the conversion of crudo iron into
steel the more volatile matters would be removed and the bottom be left as a hard
coherent mass, capable of great resistance to both mechanical and chemical action.
It is evident ordinary furnaces may be lined in a manner analogous to that above
described, but we consider our Invention particularly applicable for Bessemer
tuyeres and converter bottoms.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said David Evans and Alexander Edwin Tucker in the Great Seal
Patent Office on the 7th December 1881.
DAVID EVANS and ALEXANDER EDWIN TUCKER, both of Rhymney Iron and
Steel Works, South Wales. "IMPROVEMENTS IN BESSEMER CONVERTER AND
FURNACE LININGS."
This Invention relates especially to the manufacture of Bessemer tuyeres and
bottoms. Hitherto it has been the practice to inanufacture Bessemer tuyeres and
bottoms of the material known as ganister, a material consisting principally of silica
with just sufficient quantity of clay to form a plastic mass when treated with water,
which when moulded into the required form is air dried or burnt in an ordinary
kiln. The tuyeres are embedded in ganister made plastic with water, the whole is
then well dried and constitutes the complete bottom of the Bessemer converter.
This method has the following disadvantages:-1st. It is difficult to thoroughly
dry the mass, and on being exposed to the intense heat generated in the converter,
steam forins, thus disintegrating the bottom and causing it to wear out very
quickly. 2nd. The ganister or silicious particles are not firmly bound or fused
together, consequently the bottom cannot well resist the abrasive action of the
blast blown in, and the action of the agitated molten metal. From these causes
and the comparatively fusible character of the material used, a large quantity of
silica is mixed up with the fluid metal, thereby delaying the completo conversion of
the crude iron into steel, and seriously affecting the quality and yield of the finished
product. Again, when the addition of clay or similar material is made to increaso
the plasticity of the mass, the refractoriness of the whole is lowered, and hence it is
less capable of resisting chemical action. The rapid wearing away of the linings
and bottoms not only necessitates constant renewal and lower yields, but also the
production of a quantity of cinder which retards the conversion of the iron, and
requires much labor for its removal. The object of our Invention is to remedy
these defects, and to obtain a material in which the cement joining its particles
shall be infusible, and which material therefore is far more coherent and harder,
and offers greater resistance to the mechanical action of the blast and of the molten
inctal than ganister mixed with water. We secure this result by using coal or
wood tar (or any heavy oil residue), or similar hydrocarbons instead of water, the
tar or hydrocarbon compounds being mixed with the ganister or fireclay in such
proportions as to form a hard yet plastic mass. We always greatly prefer to use
tar when it is readily obtainable. Thus in applying our Invention to the making of
bottoms for Bessemer converters, we take tar which preferably has been boiled to
free it from water and light volatile oils in order that the bottom, when made, may
be more quickly dried, and so have less tendency to split by the undue generation
of gas in the converter. The tar at 20° C. should havo about the same consistency
as ordinary treacle at 20° C., which consistency we obtain by boiling it with solid
pitch or bituminous coal, crushed flour fine, or simply by prolonging the boiling.
We prefer however the use of bituminous coal. We then mix such tar while hot
with about ten times its weight of finely ground ganister (such as is ordinarily
used for making bottoms and linings) under edge runners or other suitable mixing
apparatus, until the mass has a tendency to flake and naturally cohere. In the
making of bottoms we then ram such mixture around either tuyeres or irou pins,
the latter being equal in number and diameter to the blast holes required. Wo
find it far best to use for this purpose red hot iron rammers. When the bottom is
complete it is dried at a temperature of about 100° C. for some twelve hours in
suitable ovens, after which period the heat is gradually increased to a black redness,

page_text: and continued at this point until no more combustible vapours are evolved; air
should be excluded as much as possible to prevent burning.
In making Bessemer tuyeres we use either finely ground ganister or dry
refractory silicious fireclay, and mix it intimately in a pug or other mill with tar
or equivalent substances; we then ram or press it into a tuyere mould provided
with tuyere holes and rods in the usual manner and dry at a low heat. In making
Bessemer converter linings and the hearths of Siemens' furnaces, the mixture before
described may be either rammed or slurried. When the mixture is to bo slurried,
that is, thrown in either on the hearth of a Siemens' furnace or the belly of a
Bessemer converter placed horizontally or between an iron pattern and the shell of
a converter without there being in any of these cases any subsequent ramming, the
proportion of tar or similar mixing or binding medium is increased so as to obtain
with the ground ganister or silicious material a mass which when piled up in a
heap has a tendency to run down and spread. A converter lining may however be
conveniently made by ramming the mixture, such as has been described as used for
bottoms, between the converter shell and a wooden or iron mould. We have
found as a result of practical working that a converter bottom made with water
and ganister in the usual way will only last from ten to thirteen blows, while the
average is less, and that in the same converter and with the same charge of iron
bottoms made and prepared from our compound will last from twenty to thirty-five
blows, this alone representing an economy for a pair of converters of several
thousand pounds sterling per year.
Having described our Invention and how the same may be practically employed,
what we claim and desire to secure by Letters Patent is,-
The herein described composition and use of a material for lining Bessemer
converters and furnaces, and especially for the making of Bessemer converter
bottoms and tuyeres, such composition consisting of ground ganister or sandstone
or similar ground silicious material mixed with tar or similar hydrocarbons,
preferably with the addition of a little coal dust, substantially in the proportions
and manner herein before described.
In witness whereof, we, the said David Evans and Alexander Edwin Tucker,
have hereunto set our hands and seals, this Seventh day of December, in the
year of our Lord One thousand eight hundred and eightyone.
DAVID EVANS.
(L.S.)
Signed, sealed, and delivered
by the said David Evans in
the presence of
DAVID ABRAHAM,
Rhymney.
Signed, sealed, and delivered
by the said Alexander
Edwin Tucker in
presence of
JOHN THOMAS,
the
ALEX. E. TUCKER. (L.S.)
Rhymney,