IMPROVEMENTS IN ARCHITECTURAL AND ENGINEERING CONSTRUCTIONS, INCLUDING MODES, METHODS, PROCESSES, AND MATERIALS FOR CARRYING THE SAME INTO EFFECT
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Thaddeus Hyatt at the Office
of the Commissioners of Patents, with his Petition, on the 13th
September 1875.
I, THADDEUS HYATT, of No. 66, Gloucester Gardens, Hyde Park,
London, County of Middlesex, Manufacturer of Patent Lights, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
ARCHITECTURAL AND ENGINEERING CONSTRUCTIONS, INCLUDING MODES, METHODS,
PROCESSES, AND MATERIALS FOR CARRYING THE SAME INTO EFFECT," to be as
follows:-
My improvements, according to one part of my Invention, relate to
joists, beams, and girders or bridges with reference to certain principles
of construction and certain processes or methods of reducing them to
"practice, the processes relating in part to improved modes of casting the
joists, beams, and girders, and which processes also apply to the casting
of rails, axles, car wheels, and other engineering materials.
According to the prevailing theory of making beams, either all cast or
all wrought metal is employed in their construction, all efforts thus far
made towards incorporating the strength of the wrought with that of the

page_text: cast metal in a way to cause the two to come simultaneously into. action
having failed. My Invention consists in part in the discovery that to
obtain this result either the web must be wrought metal to admit of a
proper union of the tie or bottom flange with it by riveting or otherwise,
the cast being then readily added as a top flange (a rolled I beam pre-
senting the most convenient form of united web and tie for adding the
cast top flange to); or where the tie is to be attached to a cast metal
web, the cast metal should form a perfect beam in itself, the sectional
area of its bottom flange being preferably as great as would be employed
were no wrought metal added to it. The tie then becomes a guarantee
against the consequences of any sudden rupture of the cast iron, and the
tie lying parallel with the bottom flange, whether this flange be straight
or curved, obtains by the mode of its union the value or advantages of
the continuous connexion existing between the continuous web and
flange of the cast metal beam, and is thus enabled to exert its resistanco
to cross strain simultaneously with the cast metal of the beam.
According to one method of reducing the principles of my Invention
to practice, I make a cast-iron beam of usual section, and above the
bottom flange thereof I cast another flange or rib, one upon each side of
the web. Into the gutters or channels formed in this way I place the
ties, a tie in each gutter, one upon each side of the web. The ties I
prefer to make with solid heads and sufficiently short, so that when
lengthened by heat and dropped into the gutters they shall on cooling
draw the heads hard up, but not so as to strain the metal. I then bring
the two metals, the cast and the wrought, into union and tension, by a
system of wedging. all along the length of the ties, sufficient longitudinal
space for this purpose being provided in the channels.
For greator security and strength I sometimes add other ties above the
bottom one, suitable flanges or ribs being cast upon the web for the
purpose, the one at the centre or neutral line being made broader than
the others, so as to be rivetted to the web in addition to the wedging,
for the purpose of holding together the parts of the beam in case of
sudden rupture.
By a variation of the mode of attaching the ties, instead of applying
them to the beam I cast the beam upon the ties, the operation of pre-
ference being performed inside of a furnace, the molten metal being
there poured upon the ties previously placed and. heated in a mould

page_text: within the heated chamber, welding chemicals being in some cases used
to facilitate the union of the metals. This process of casting in hot
moulds in a heated chamber also tends to toughen the cast. metal, a
part of my Invention also consisting in casting spurs, indents, or other
preparation upon the beam for receiving and securely holding asbestos,
plastic, or equivalent heat-resisting material.
According to another process or method of uniting the tie to the
beam, I make the tie in a flat shape, as long and broad as the under side
of the bottom flange, against which it is placed, having first been heated,
the ends being made with solid heads to take into suitable recesses at the
ends of the beam. Although it may then be rivetted to the flange I prefer
to provide a special rivetting flange for it at the neutral line or centre of
the beam; and I prefer to scollop the edges of the bottom flange for the
purpose of allowing the rivetting bolts to pass by' said flange and go up to
the neutral line flange, where they are then secured by nuts or rivet heads.
This method I also propose to vary by the use of. welding chemicals,
so as to weld the flat tie to the face of the bottom flange in place of
rivetting, by placing the tie, suitably washed over or otherwise pre-
pared with the welding chemical, according to well-known methods of
employing such materials in welding metals, in a furnace with the
mould, and pouring the molten metal upon it, as already described.
According to another part of my Invention, my improvement consists
in attaching cast to wrought metal to make beams, the modes of doing
which are many.
One mode consists in employing a rolled beam of convenient section,
the for example, as the base upon which to cast, or form the top
flange of cast metal. By one method of attachment cast-iron blocks of
suitable size and shape are prepared and applied to the top of the web of
the shaped beam, which, when made fast by rivetting or otherwise,
and wedged closely together, form a solid top flange capable of acting
in concert with the wrought metal in resistance to cross strains.
By another method such blocks are cast upon the web aforesaid and
rivet themselves there, the beam having been placed in the flask with
suitable holes made along the web near its top edge, and the molten
metal then poured in upon it, dividing slips being used to form the
leole

page_text: are made use of, but by my improvement the brackets are cast upon the
beams, which simplifies and cheapens the construction.
According to another part of my Invention my improvement consists
in making illuminating lattice beams upon the principle of tie con-
struction herein set forth. In this process the gratings may be cast
upon the beam, or several gratings suitably proportioned may be bolted
together to form the beam, the ties being placed in the channels or
gutters and wedged up in the manner described.
The method of wedging herein-above set forth to produce a perfect
union between a wrought-iron tie and the beam to which it is attached
I also apply to brick, concrete, and stone constructions by substantially
the same mode of procedure.
According to another part of my Invention my improvement consists
in making cast metal joists, beams, girders, axles, rails, car wheels, and
other cast metal objects, wholly of cast metal by casting the same in
heated moulds in a heated chamber or furnace as herein-above set forth,
the moulds being heated sufficiently high before receiving the molten
metal to not suddenly rob it of its heat; this method gives the metal
longer time to cool, the effect of which is in a manner to anneal and
thus toughen it. .