A NEW OR IMPROVED METHOD OF MANUFACTURING, BY HOT ROLLING IRON OR STEEL, PLATES, BARS, GIRDERS, BEAMS, AND THE LIKE, AND THE NEW APPLICATION IN SUCH MANUFACTURE OF SPECIALLY PREPARED ROLLERS OR CYLINDERS FOR THAT PURPOSE
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Just Larue at the Office of the
Commissioners of Patents on the 14th March 1881.
JUST LARUE, of 17, Boulevard Saint-Martin, Paris, France, Engineer. "A NEW
OR IMPROVED METHOD OF MANUFACTURING, BY HOT ROLLING IRON OR STEEL,
PLATES, BARS, GIRDERS, BEAMS, AND THE LIKE, AND THE NEW APPLICATION IN
SUCH MANUFACTURE OF SPECIALLY PREPARED ROLLERS OR CYLINDERS FOR
THAT PURPOSE."
My Invention relates to a new or improved method of manufacturing, by hot
rolling iron or steel, the articles herein after mentioned, and the new application in
such manufacture of specially prepared rollers or cylinders for that purpose.
1. All forms or types of truss work, lattice-girders, and half lattice girders
hitherto made, by using iron or steel bars connected with each other by riveting.
2. A new class of mixed forms which I term panelled truss work.
3. Sheets, plates, and bars, perforated whilst hot by rolling, superseding those
perforated when cold, by the ordinary methods.
For obtaining truss work I cut or engrave the finishing rolls or cylinders with
grooves or channels either oblique to or parallel with the axis of such rolls or
cylinders, the outline, depth, and direction of these grooves or channels being
determined according to the kind of truss required.
Heretofore the rolls or cylinders of rolling mills have been grooved or channelled
in the lathe, consequently in the direction of their circumference, but the hardness
of the rolling surfaces has hitherto prevented their being made with grooves or
channels parallel with or oblique to their axis.
In the practical manufacture of my rolling cylinders I can use for cutting
the grooves or channels, either screw-cutting lathe, milling machinery, planing
machinery, or other machine tools, such as emery'wheels, and the like; if necessary
the rolls or cylinders may be cast, and receive in the casting the requisite grooves
or channels according to the type or pattern to be produced.
By using rolls or cylinders thus prepared, I am enabled to manufacture either
truss-work having isosceles triangles between the flanges of the girder or beam
(Fig. 1), and those with scalene triangles of all kinds (Figs. 2 & 3), or truss-work

page_text: on Towns' system, having one or several meshes or reticulations formed by the
crossing of the bars which obliquely connect the upper and lower flanges of the
girder or beam (Fig. 4).
The bars forming the truss-work, of whatever pattern or type, may have the
outline either of the plates or bars so frequently used, or an outline imparting
greater rigidity by projecting ribs on one or on each face of the bars of the truss-
work, and it will be sufficient for producing the same to engrave the desired outline
or shape upon one or both the finishing rolls or cylinders.
By making the grooves or channels of a suitable outline only in the direction of
the axis of the rolls or cylinders, vertical stays will be produced, which will form
between the flanges of the girder or beam I shaped bars, squares, or panels, having
a very slight body or web (ame) between the stays (Fig. 5).
If cross bars be added between the stays, a type, or Paxton's, or pattern of
X shape will be produced (Fig. 6).
In lattice girders with oblique crossed bars, vertical stays may be produced at
the same time, thereby maintaining the flanges of such a girder at their normal
distance from each other when a load is placed upon the same (Fig. 7.)
By engraving the rolls or cylinders with suitable designs the flanges may also be
connected together by ornamental work, which will effect, as nearly as possible, the
theoretical conditions of resistance of the above mentioned types.
I must remark that the metal prepared by the roughing rolls or cylinders in the
various shapes required, such as in bars of I; T, LU - form and in
sheets, will be trussed by the engraved finishing rolls or cylinders, but they will be
what I term panelled trussed-work, for the metal strongly compressed between the
ribs which form the truss-work remains in the shape of panels of thin sheet metal
between these ribs, so that my method thus originates a new class of mixed forms
or patterns which should be termed panelled truss-work, while the ordinary trellis
will be termed open truss-work.
To manufacture open truss work by my method it will be sufficient to clear away
or punch out, when cold, their thin panels, either by an automatic punching
machine or by a stamping mill, one roll or cylinder of which will be engraved
according to the design corresponding to the truss-work to be cleared or opened,
but the relief of which will be higher and sharper so as to enable it to drive the
slight panels out of the reticulations or meshes of the truss-work.
Now according to my Invention truss-work lattice girders of considerable
dimensions can be produced by means of the apparatus at present in use in iron
works, by simply modifying the rolls or cylinders by engraving them with grooves
or channels, arranged as above indicated; by more powerful and special apparatus
larger pieces can be produced, from which girders or beams of greater size can be
constructed, but under the present conditions large girders or beams can be
constructed by superimposing trussed pieces until the required size be attained,
and by well riveting the same at the junction ribs or flanges A, B, (Fig. 8) their
solidity will be ensured.
For I bars of medium size the upper and lower flanges will be directly obtained
by the ribs being formed in the same piece as the truss work by rolling; for large
sizes, however, the flat top and bottom plate will be attached to the ribs by riveting,
as indicated in Figure 9, and this will allow the width and thickness of the plates
or flanges to be varied, as may be required, by increasing the number of sheets or
plates, and by modifying their proportions. If a tubular girder with several
internal webs (âmes) is required (Fig. 10), it would be produced in like manner by
placing the requisite number of webs (âmes) between the plates or flanges, and by
superimposing the same if necessary as above stated for attaining the desired size.
It is also evident that by crossing or breaking the joints of the plates or flanges
on those of the trussed girder, girders of any length may be produced, and that by
giving to the said plates or flanges in the centre of the girder the swelling. in cross
section, determined by calculation, it will be sufficient to place thereon the number
of plates deemed necessary. For making plates or bars perforated while hot, the

page_text: finishing rolls or cylinders are provided with projections of the form of the required
perforations, which projections are either raised on the body of the cylinders or
produced by steel punches with cone shaped ends fitted into one or both the
rolls or cylinders; the sheets, bars, angle irons, and the like, perforated while hot
in this way, can be used in building and in boiler making for receiving the
connecting rivets in their perforations.
The advantage offered by my method is that it allows of the economical
production of bars, plates, and sheets, for metal trussed girders or beams which,
whether opened or panelled, utilize the metal better with regard to uniformity of
weight, as the criticisms on girders or beams, by eminent engineers of various
countries, are based on the following observations:-"The flexures of trussed
girders or beams for an equal quantity of the material employed are much greater
than those of well made solid sided girders;" this evil has no other cause than the
want of solidity of the crossed and riveted bars which constitute the trussed
girder, and of its attachment to the plates or flanges; in fact, this solidity can not
be absolute, the riveted joints under the influence of a load soon become loose to a
certain extent, which consequently increases the flexures; furthermore, the bars of
the truss-work really only resist in proportion to the number of fibres corresponding
to the section of the rivets. By my method of manufacture this is not the case, the
bars of 'the truss work being joined to the plates or flanges by their entire sectional
area, as they are rolled from the same piece; not having any rivet holes which
render ineffective all the longitudinal fibres corresponding therewith, the whole of
the metal is operative in its sectional area, there is nothing further to be feared,
neither the shearing of the rivets nor of their working loose in their holes, nor
what may be termed "hinging" at the joints, which are the only causes "of the
greater flexures of latticed or trussed girders or beams and truss bridges."
My method also effects a considerable saving of metal by the non superposition
of the bars at the points of intersection or crossing of the truss work and at the
joints with the plates or flanges thereof.