AN IMPROVEMENT IN THE CONSTRUCTION OF IRON OR STEEL VESSELS
Year: 1884

page_text: I, JOHN IMRAY of No 28 Southampton Buildings Chancery Lane, in the county
of Middlesex, Consulting Engineer and Patent Agent do hereby declare the nature
of the said invention for "AN IMPROVEMENT IN THE CONSTRUCTION OF IRON OR
STEEL VESSELS" to be as follows:-
This invention relates to a mode of constructing iron or steel vessels, whereby,
with a given weight of material greater strength to resist flexure and penetration is
obtained than by the ordinary modes of construction, and leakage at the joints of
the plates is more effectually prevented, while great facility is given for removing a
damaged plate and substituting a sound plate, without disturbing adjoining plates.
For this purpose, instead of overlapping the plates of the successive tiers and
rivetting them to each other, there is interposed between each tier of plates and the
next in order a horizontal band forming a rib projecting inwards at right angles to
the contour. On each side of this band is rivetted an angle iron, and to these
angle irons are rivetted the plates of the two tiers, the edge of the band being made
to project a little beyond the external surface of the plates and being afterwards
caulked down by the hammer, so as to form a continuous burr or rivet covering the
edges of the adjoining plates. The bands are made of greater breadth in the lower
part of the hull and in the middle of the vessel than they are in the upper part of
the structure and towards the ends of the ve-sel, so as to form deeper ribs where
greater strength is required. Where a floor is required, it may be of wood fixed on
angle irons rivetted to the inner edges of the deep bottom ribs, or flat bars crossing
each other diagonally may be secured to these angle irons, so as to give increased
rigidity to the structure. The decks are laid on girders which at each end, where
they meet the sides of the vessel, are widened out in knee form and are secured by
angle irons to the plates and to the two inwardly projecting ribs, the one above
and the other below the knee end of the girder. The bulkheads are notched at the
sides for the passage through them of the continuous horizontal ribs and their
angle irons, which, as well as the plates are secured to the bulkheads by angle irons
and suitably bent covering plates rivetted to both. In constructing a vessel in
this manner, it is convenient in the first place to make the bulkheads with their
rh 017

page_text: notches in the proper places to receive the ribs, and to set them up at the required
distances apart, so as to form a framework to which, in the first place the horizontal
rib are attached, the plates being then rivetted to the ribs. When the distance
from bulkhead to bulkhead is too great to afford proper support to the ribs,
temporary framings can be erected between them to carry the ribs until the plating
is done. In order to prevent lodgement of water on the horizontal ribs, drainage
holes are cut through them at intervals, care being taken that these holes in the
several ribs do not come in vertical lines, which would have the effect of weakening
the structure in these places.
Dated thin 12th day of Tehran 1884

page_text: I, JOHN IMRAY of No 28 Southampton Buildings, Chancery Lane in the county.
of Middlesex, Consulting Engineer and Patent Agent, do hereby declare the nature
of my said invention for "AN IMPROVEMENT IN THE CONSTRUCTION OF IRON OR.
STEEL VESSELS" and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
This invention relates to a mode of constructing iron or steel vessels, whereby,
with a given weight of material, greater strength to resist flexure and penetration
is obtained than by the ordinary modes of construction, and leakage at the joints
of the plates is more effectually prevented, while great facility is given for removing
a damaged plate and substituting a sound plate without disturbing adjoining plates.
For this purpose, instead of overlapping the plates of the successive tiers and'
rivetting them to each other, there is interposed between each tier of plates and
the next in order a horizontal band forming a rib projecting inwards at right angles
to the contour. On each side of this band is rivetted an angle iron and to these
angle irons are rivetted the plates of the two tiers, the edge of the band being made
to project a little beyond the external surface of the plates and being afterwards
caulked down by the hammers so as to form a continuous burr or rivet covering
the edges of the adjoining plates. The bands are made of greater breadth in the
lower part of the bull and in the middle of the vessel than they are in the upper.
part of the structure and towards the ends of the vessel, so as to form deeper ribs
where greater strength is required. Where a floor is required, it may be of wood'
fixed on angle irons rivetted to the inner edges of the deep bottom ribs, or flat bars
crossing each other diagonally may be secured to these angle irons so as to give
increased rigidity to the structure. The decks are laid on girders which at each
end, where they meet the sides of the vessel are widened out in knee form and are
secured by angle irons to the plates and to the two inwardly projecting ribs, the
one above and the other below the knee end of the girder. The bulkheads are
notched at the sides for the passage through them of the continuous horizontal ribs.
and their angle irons which, as well as the plates, are secured to the bulkheads by
angle irons and suitably bent covering plates rivetted to both. In constructing a
vessel in this manner, it is convenient in the first place to make the bulkheads with
their notches in the proper places to receive the ribs and to set them up at the
required distance apart so as to form a framework, to which, in the first place, the
horizontal ribs are attached, the plates being then rivetted to the ribs. When the
distance from bulkhead to bulkhead is too great to afford proper support to the
ribs, temporary flamings can be erected between to carry the ribs until the plating
is done. In order to prevent lodgment of water on the horizontal ribs, drainage
holes are cut through them at intervals, care being taken that these holes in the
several ribs do not come in vertical lines, which would have the effect of weakening.
the structure in these places.
Figs 1, 2 and 3 of the accompanying drawings shew the manner of forming the
junction of the horizontal ribs with the skin plates of a vessel as above described.
Fig. 4 shews a part cross section of a screw steamer with water ballast the section
being taken at the engine room. Fig. 5 shews a part cross section towards the end
of the vessel. Fig. 6 shows a part cross section of a sailing vessel with spar deck.
Figs. 7 and 8 hew two arrangements of the bulkheads for screw steamers.
Figa. 9, 10 and 11 show details of the jun·tion of a bulkhead with the horizontal"

page_text: rìbs; figs. 12, 13, 14, 15, 16, 17 and 18 shew three arrangements of vertical
supporting ribs or distance plates between two horizontal ribs. Fig. 19 shews a
transverse section of a vessel having a wooden floor with its means of attachment.
Fig. 20 shews & developed plan of the same. Fig. 21 shews an arrangement with
metal floor applicable with this improved construction. Figs. 22 and 23 shew a
side view and section of a horizontal rib with its angle irons having holes formed
through them for the escape of water. Fig. 24 shews the details of the connections
of a beam of the main deck.
The plates A A of the vessel butt on either side against the horizontal ribs B, to
which they are secured by two angle irons C C rivetted both to the plates and to
the rib, as shewn at figs 1, 2 and 3, in addition to which the projecting edges of the
ribs are caulked down firmly against the edges of the plates by hammering. Fig. 1
shews the parts rivetted together before caulking down the protruding end of the
rib, Fig. 2 shews the manner of spreading the end of the rib laterally by means of
a chisel, and-fig 3 shews the caulking down completed. Each plate A is supported
by the contiguous ones; the angle irons are directly and strongly secured to the
outer edges and the deck beams are afforded a maximum effect against transverse
strain.
The application of this construction offers certain advantages, which may be
enumerated as follows:
It is evident that in applying this method of construction to existing forms of.
ships, no increase of weight will result. The horizontal ribs only take the place of
those parts of the old method of construction which constitute the overlapping
of the plates, the frames, angle irons, &c; thus, if the angle iron of the frames, and
the reversed angle iron be cut off in lengths corresponding to the intervals between
the frames and to this be added the amount of lap of the plates this will yield an
amount of metal equal to that of the horizontal ribs.
The number of tiers of plates being equal in both systems, the number of
horizontal ribs will also not be greater than that of the frames of the present
construction. In place of the dissimilar angle irons of the frames, and reversed
angle irons now employed two similar sections of angle irons are used of such a
form as to offer great rigidity against' penetration. For this purpose, the face of
the angle iron that is applied to the ship's plating is only made of the width
required for rivetting, while the other face is made of increased depth, in order to
withstand both longitudinal flexure and penetration.
The improved construction consequently offers the advantage of requiring skin
plates of a less width than heretofore and consequently capable of more easy
manufacture and manipulation.
The resistance to penetration of the existing constructions is comparatively small,
as even though the decks be framed in metal, they are over 6 feet apart, and the
beam plates are notched for the passage of the frames or they are simply stopped
short behind them and consequently either are weakened by the notching or leave
spaces in which the skin and its backing are unsupported, whereas by the improved
construction, the beam plates E (fig. 24) are carried through the skin A, and thus
form a solid structure therewith, affording great strength.
The resistance to longitudinal flexure is also greatly increased as will be readily
found on calculation of the effective parts of the section of the old construction
and the improved construction. The latter will also offer less resistance to speed,
I will not foul so readily, and will afford increased available room in the hull 'for
given dimensions.and angles.
As the beams D may, under the improved construction, be placed at any desired
distance apart they may be arranged to suit the positions of the masts, engines and
boilers and other fittings of the vessel.
Lastly, it will be seen that the fixing and rivetting as also the unrivetting and
removing of a skin plate can be effected with facility, without requiring to disturb
any of the contiguous plates för this purpose.

page_text: The application of the improved system of construction involves certain
modifications in the setting out of the ship, in the construction of the bulkheads,
floors, ceilings &c, which I will now describe.
First. In setting out the lines of the ship, the contours of the vertical ribs or
frames will not have to be considered, but only those of the horizontal ribs, the
curves of which will have to be set out according to the lines of the vessel. In
then starting from the main frame, the lines of the tiers of plates will have to be
marked out in order to set out on the templates the positions to be occupied by the
distance plates, of which one is shewn in elevation and section at figs. 12 and 13.
The numerous watertight bulkheads now employed will facilitate the construction,
inasmuch as these are erected in the first instance, having notches at the required
points for receiving the horizontal ribs, as shewn at F figs. 7 and 8, the notches a
being made sufficiently large to admit of the accurate adjustment of the ribs
therein.
Where the bulkheads are too far apart to support the intervening lengths of the
ribs efficiently, intermediate temporary supports may be applied. The ribs for the
lower deck will be first placed in position, in order that the beams and beam plates
may be at once fixed, as these when adjusted, will in their turn temporarily support
the parts to be fixed above and below them. As the horizontal ribs are placed in
position they will be regulated relatively to the next one by means of the distance
plates, which will have been previously constructed and the details of which are
shewn on the accompanying drawings. When only the skin plates remain to be
fixed, these are cut according to templates in such manner that they can be placed
freely between the ribs, and after rivetting them to the angle irons the projecting
edges of the ribs are trimmed and are then caulked down as already described.
Second. The watertight bulkheads F are secured to the sides by means of
lengths of angle iron and where the horizontal ribs B are situated covering pieces G,
figs, 9, 10 and 11, all moulded to one and the same profile are employed, the parts
indicated by black lines at c c being filled in with caulking to render them
watertight.
Third. The distance plates are shewn in elevation and section at figs. 12 and 13,
a separate view of the plate b being shewn at fig 4. Fig. 15 shews an elevation of
another construction, in which the plate 6 is of the form shewn at fig. 16, and
fig. 17 shews another modification of which the plate b is shewn at at fig 18.
The skin plates are rivetted to each angle iron of the horizontal ribs by either
one row or two rows of rivets, according to the dimensions.
Fourth. The ordinary floor beams are constructed as shewn on the drawings; at
the watertight bulkheads, they will form part of the latter while providing for the
passage of the horizontal ribs.
Fifth. At the rear end, should the width between two decks be considered too
great to admit of only two skin plates being used, a joint may be made by means
of a small piece of ordinary plating, such as is sometimes used in the first plate
under the tube of the stern post.
Sixth. The arrangement and mode of attachment of the flooring is shewn at
figs. 19, 20 and 21 of the drawings. At figs 19 and 20 is shewn a section and
developed plan of a wooden flooring, extending between the angle irons o o. Fig. 21
shews the flooring formed of diagonal bars d d crossing each other and rivetted at
their ends to the angle irons of o¹. The weight of this flooring will be the same
as that of the wooden one but a greater hold space will be obtained thereby.
Seventh: To allow the water to run off there are formed at distances of three
feet apart holes H in the horizontal ribs, as shewn at figs. 22 and 23; independently
of these holes there is provided for each compartment against the lowest partition
a metal conduit of large section.
The holes H are not arranged vertically one above the other in the different
horizontal ribs in order that they may not collectively form a weak section at any
one point.

page_text: Eighth. Fig. 24 shews the details of construction of a beam with knee shaped
ends for the main deck.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
The herein described improved method of constructing iron or steel vessels,
wherein the skin plates are secured to the angle irons of horizontal ribs the front
edges of which project between the contiguous edges of two plates and are caulķeḍ
down so as to form a watertight joint between them,
Dated this 7th day of November 1884.