Improvements in the Process of and Apparatus for Moulding Briquettes of Cement or the like Material to be Employed for Testing the Qualities thereof.
Year: 1886

page_text: Date of Application, 6th Nov., 1886
Complete Left, 26th May, 1887.
Complete Accepted, 28th June, 1887
Improvements in the Process of and Apparatus for Moulding
Briquettes of Cement or the like Material to be Employed
for Testing the Qualities thereof.
I, THOMAS ARNOLD of West Hartlepool in the County of Durham, Cement Maker,
do hereby declare the nature of this invention to be as follows:-
My Invention relates to the process of moulding cement, or the like material, into
briquettes of the form usually employed for subjecting the cement to tensile or
compressive strains in order to test its quality.
My object is to secure the proper density of the cement in the briquettes by
compressing the cement to the required form in the dry state before water is added,
instead of the usual way of first mixing the water with the cement by hand and
afterwards moulding it in the wet state to the required form of briquette. The
density of the cement in briquettes moulded in the wet state depends upon the skill of
the moulder, and is often affected by the incorporation of air bubbles, which form
cavities in the briquette so that the specified sectional area of the briquette, at the
plane of fracture or least resistance, is that of the sectional area of cement available
for resisting the test, plus the area occupied by the air bubble cavaties, and the result
of the test is often misleading as to the quality of the cement in consequence of the
actual sectional area of the cement being only a part of the apparent or specified
sectional area of the briquette.
In carrying my invention into effect, I provide an apparatus divided into com-
partments or boxes for moulding the briquettes in the dry state, that is, in the state
in which cement is stored or kept ready for mixing with water. The compartments
or moulding boxes can of course be provided of any required dimensions and internal
form corresponding to the required size and configuration of the briquettes, but in
ordinary practice the square inch is the standard sectional area to which the test is
applied, and for this sectional area the moulds should be one inch wide and one and
three-quarters inch deep; the cement is poured into each mould from the spout of a
can, or by any other convenient method, a uniform density or distribution of the
Price 8d1

page_text: cement being secured in each briquette by constantly shaking each mould or com-
partment as the cement flows in; the amount of cement poured in is the same as
would be used by an expert hand in moulding a briquette of the same dimensions by
the wet process.
By pressing accurately fitting dies or stamps into the moulds or
compartments to a sufficient distance, as for instance, three-quarters of an inch in the
moulds for inch square briquettes, the cement is compressed to the required size of
the briquette, and for the purpose of applying the required pressure to the dies or
,stamps, any kind of mechanism may be employed by which the application of the
pressure can be easily controlled; on the removal of the dies or stamps the specified
or requisite quantity of water should be admitted to each mould or briquette which
absorbs it, the briquette may then be removed from the mould and is ready for the
testing machine.
Dated this 5th da. of Naomhan 100

page_text: Improvements in the Process of and Apparatus for Moulding
Briquettes of Cement or the like Material to be Employed
for Testing the Qualities thereof.
I, THOMAS ARNOLD, of West Hartlepool in the County of Durham, Cement
Manufacturer, 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 :-
My Invention relates to the process of moulding cement or the like material into
briquettes of the form usually employed for subjecting the cement to tensile or
compressive strains in order to test its quality or powers of resistance to fracture.
My object is to secure the proper density of cement in the briquettes by
compressing the cement to the required form in the dry state before water is added,
instead of the usual way of first mixing the water with the cement by hand and
moulding it in the wet state to the required form of briquette. The density of the
cement in briquettes moulded by hand in the wet state is liable to vary with the skill
of the moulder and therefore gives unreliable results when tested; this variation is
due to the incorporation of air bubbles which form cavities in the cement so that the
specified sectional area of the briquette at the plane of fracture or least resistance is
that of the sectional area of solid cement plus the area occupied by the air bubble
cavities, and the result of the test is often misleading as to the quality of the cement
in consequence; the actual sectional area of the cement available for resistance to
fracture being only a part of the apparent or gross sectional area of the briquette.
In carrying my invention into effect I provide an apparatus suitably constructed
for moulding the cement into briquettes of the intended form and proper density and
in the dry state, and for enabling the water to be subsequently absorbed into the
cement.
And in order that my invention may be fully understood I will now proceed to
describe the process of moulding the briquettes and for that purpose shall refer to the
accompanying drawings in which suitable means or apparatus for applying my
invention is illustrated.
Fig. 1. is a front elevation of a moulding machine constructed in a manner similar
to a letter press; Fig. 2. illustrates in plan a moulding box for moulding the cement,
and Fig. 3. the corresponding die for applying the requisite pressure; Fig. 4. is a
tray or pan containing water formed into separate divisions, if preferred each division
being capable of holding a moulding box, or the arrangement for separate divisions
may be omitted.
The moulding box a is placed in position in the tray bor in one of the divisions
thereof and is then supplied with the specified quantity by weight of dry cement
which is moulded to the proper form and density by sufficiently rapping or otherwise
vibrating the moulding box as the cement is poured in. One or more moulding
boxes a supported on the tray or soaking dish b are then placed in position under the

page_text: press c in order that the die d may be pressed into the moulding box to its intended
depth; for instance, until the top surfaces of both die and moulding box form one
level, this operation may be repeated with a series of moulding boxes all supported on
one tray or soaking dish. By supplying water to the tray or soaking dish the
requisite moisture is absorbed into the cement enclosed in the moulding box for
producing a hard set briquette of uniform density, or this may be effected by complete
immersion of the moulds in water.
It is of course obvious that as the object of my invention is to mould the briquettes
in the dry state and to add water for absorption afterwards as a quicker and more
reliable process than mixing the cement and water together first to he moulded by
hand, the particular construction of mechanical parts or apparatus by which my
invention may be carried out may be varied in design without departing from the
nature of my invention so long as the briquette is moulded in the dry state so as to be
of the proper density by avoiding the formation of air bubble cavities.
Having now described the nature of my invention and how the same may be
applied to the process of moulding cement briquettes, what I claim is :—
In the manufacture of briquettes of cement to be employed for testing the powers
of resistance thereof, the process of moulding the briquette in the dry state and
afterwards adding water thereto, substantially as and for the purpose as hereinbefore
described.