IMPROVEMENTS IN THE MANUFACTURE OF SILICA FIRE BRICKS SILICA FIRE CEMENT AND SILICA FIREWARE GOODS GENERALLY
Year: 1882

page_text: LETTERS PATENT to Henry Edwards of Braich-y-Cymmer in the County of
Glamorgan and Henry Harries of Glyn Neath in the County of Glamorgan
for an Invention of IMPROVEMENTS IN THE MANUFACTURE OF SILICA FIRE
BRICKS SILICA FIRE CEMENT AND SILICA FIREWARE GOODS GENERALLY
PROVISIONAL SPECIFICATION left by the said Henry Edwards and
Henry Harries at the Office of the Commissioners of Patents on the 27th
December 1882.
HENRY EDWARDS of Braich-y-Cymmer in the County of Glamorgan and Henry
HARRIES of Glyn Neath in the County of Glamorgan IMPROVEMENTS IN THE
MANUFACTURE OF SILICA FIRE BRICKS SILICA FIRE CEMENT AND SILICA
FIREWARE GOODS GENERALLY
This invention relates to improvements in the Manufacture of Silica Fire Bricks,
Silica Fire Cement and Silica Fireware Goods generally
Silica Fire Bricks are generally made by adding to the ground Silica a small
percentage of Lime water ranging from one to three per cent such Lime being in
the condition of milk of Lime and causing the siliceous base to become plastic and
enable the bricks &c to be moulded into whatever form desired. After moulding
such bricks have to be placed on a hot stove and carefully dried before being taken
to the kiln and the cost of the fuel used in such stove forms no inconsiderable item
in the prime cost of the goods. It is also necessary or desirable in this lime
process to allow the mixed Silica and Lime to remain in a heap for from twelve to
twentyfour hours to "mature" and then before it reaches the moulder the mass
has to be "tempered" by the treading of a workman. Further than that the
process of stove drying above alluded to is a lengthy one so that extensive and
expensive stove room is required even for a small daily make of bricks.
We have discovered that by the use of a small proportion of Portland Cement
either in addition to or in lieu of the lime an improved brick can be manufactured
which can be moulded straight from the mill without the necessity of "maturing
or "tempering" and which when moulded will set and dry in a very short period
22

page_text: with or without heat.
The effect is that the cost of manufacture is materially less
than the cost by the Lime process alone and the moulded article presents a better
shape and with sharper edges.
The "Silica" or siliceous material to which we apply the Portland Cement as
above indicated may consist of Calcined Flints Dinas Stone Millstone grit
Gannister Sandstone or Sands.
Such of the above materials as require grinding may be ground wet or dry and
the Portland Cement may be mixed with the material either in the grinding-mill
or by a separate mixing machine or by manual labor but we prefer to apply it in
the Mill during the process of grinding.
The proportion of Portland Cement may vary according to the material in use
and the amount of heat the manufactured goods may be intended to resist.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Edwards and Henry Harries in the Great Seal Patent
Office on the 23rd June 1883.
HENRY EDWARDS of Braich-y-Cymmer in the County of Glamorgan and HENRY
HARRIES of Glyn Neath in the County of Glamorgan IMPROVEMENTS IN THE
MANUFACTURE OF SILICA FIRE BRICKS SILICA FIRE CEMENT AND SILICA FIREWARE
GOODS GENERALLY
This invention relates to improvements in the manufacture of silica fire bricks,
silica fire cement and silica fireware goods generally. Silica fire bricks are
generally made by adding to the ground silica a small percentage of Lime ranging
generally from one to three per cent such lime being in the condition of milk of lime
and causing the siliceous base to become plastic and enable the bricks etc to be moulded
into whatever form desired. After moulding such bricks have to be placed on a
hot stove and carefully dried before being taken to the kiln and the cost of the fuel
used in such stove forms no inconsiderable item in the prime cost of the goods. It
is also necessary or desirable in this lime process to allow the mixed silica and lime
to remain in a heap for from twelve to twentyfour hours to "mature" and then
before it reaches the moulder the mass has to be "tempered" by the treading of a
workman Further than that the process of stove drying, above alluded to, is a
lengthy one, so that extensive and expensive stove room is required even for a
small daily make of bricks.
נו
We have discovered that by the use of a small proportion of Portland Cement
either in addition to or in lieu of the lime an improved brick can be manufactured
which can be moulded straight from the mill without the necessity of "maturing'
or "tempering" and which when moulded will set and dry in a very short period
with or without heat. The effect is that the cost of manufacture is materially less
than the cost by the lime process alone and the moulded article preserves a better
shape and with sharper edges.
The silica or siliceous material to which we apply the Portland Cement as
above indicated may consist of Calcined flints Dinas Stone Millstone grit,
Gannister Sandstone or sands. Such of the above materials as require grinding
may be ground wet or dry and the Portland Cement may be mixed with the
material either in the grinding mill or by a separate mixing machine or by manual
labor but we prefer to apply it in the mill during the process of grinding.
The proportion of Portland Cement may vary according to the material in use
and the amount of heat the manufactured goods may be intended to resist.
An appropriate mode of manufacturing is as follows:-the Siliceous material is
ground by Edge runners lime water or clear water, hot or cold, preferably hot,
being supplied to the material while grinding in sufficient quantity to moisten the
ground material fit for the moulder. As the charge is approaching the desired
fineness the Portland Cement is then introduced and becomes mixed properly with
the mass during the last few turns of the mill. The mixed material is then
removed from the mill and at once either thrown into or run into the moulds and
when set the Bricks or moulded articles are placed in the kiln and baked in the
ordinary manner
In making Fire Cement the proper proportion of Portland Cement is added and
mixed with the ground Siliceous material in a dry state and so delivered to the
customer, and is used in the way that ordinary mortar is used in common
brickwork to set the bricks or other moulded articles in the furnaces where they
are to be used and is also used as furnace lining and Juting and for repairing
furnaces.

page_text: The proportion of Portland Cement will vary according to the heat the bricks
are required to resist and will be larger when lime is not used than when it is.
We find that for bricks required to resist great heat it is well to add to the
Siliceous material one per cent of Lime and two and a half per cent of Portland
Cement.
Having thus described the nature of our invention and the manner of carrying
the same into effect we declare that we claim the use of Portland Cement (with or
without Lime) with the Siliceous material above. described for the purposes above
described.
In witness whereof we the said Henry Edwards and Henry Harries have
hereunto set our hands and seals this Twenty third day of June, 1883.