Improvements in Discharging the Contents of Dredging Barges.
Year: 1893

page_text: Date of Application, 17th Jan., 1893
Complete Specification Left, 19th Aug., 1893-Accepted, 30th Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in Discharging the Contents of Dredging Barges.
I, LODEWYK JAN RUTGER HOLST, of 9, Hemony, Laam, Amsterdam,
Representative of the Naamlooze Vennootschap "Werf Conrad" of Haarlem, both
in the Kingdom of the Netherlands, do hereby declare the nature of this invention
to be as follows:
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་
This invention relates to an improved method of and means for discharging the
contents of dredging barges by suction.
4
In carrying out my invention I provide for lowering the suction pipe through the
contents of the barge to the bottom thereof by forcing a supply of water through
the said suction pipe whereby a passage will be cleared allowing the pipe to
gradually fall to the bottom of the barge. In order to obtain the necessary supply
of water through the suction pipe I advantageously connect the latter to the pipe
through which the water for diluting the contents of the barge passes, a suitable
valve being employed to shut off the water when required.
Dated this 16th day of January 1893
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
66
Improvements in Discharging the Contents of Dredging Barges.
I, LODEWYK JAN RUTGER HOLST, of 9, Hemony, Laam, Amsterdam,
Representative of the Naamlooze Vennootschap Werf Conrad," of Haarlem, both
in the Kingdom of the Netherlands, do hereby declare the nature of this invention
and in what manner the same is to be perforined, to be particularly described and
ascertained in and by the following statement:-
This invention relates to an improved method of and means for discharging the
contents of dredging barges by suction.
The removal of dredged material, from loaded barges, for instance, has hitherto
presented great difficulties, especially when the material in question is of a sandy
or clayey consistence. There is no difficulty in removing the supernatant fluid.
through the nozzles of pump-tubes, but on the other hand, the silt or clay remains
behind.
By my invention I overcome this difficulty by first lowering the nozzle of a
pump-tube on to the surface of the dredged material, and then driving a powerful
stream of water through the tube by means of a force pump, the water as it issues
washing up the dredged material which lies around and under the nozzle of the
pump-tube, and thereby, in conjunction with the weight of the tube, facilitates the
penetration of the nozzle into the mass of material. As soon as the nozzle has
reached the floor of the barge, the water from the force pump is conducted by to
suitable arrangement of cut-off mechanism into another tube and on to the dredged
material to stir it up and loosen it whilst a suction pump being placed in communi-
cation with the said nozzle lifts and removes the loosened mass.
As a feature, characteristic of the present arrangement, is to be noticed the fact
that the stream of water is only forced through the nozzle at the commencement of
the process, and only until the nozzle has reached the floor of the barge, and the water
is thereafter, by again operating the cocks, conducted on to the surface of the
dredged material through another tube, whilst in the forms of apparatus hitherto in
use, the stream of water is constantly directed to the foot of the pump.

page_text: Figure 1 is a cross section;
Figure 2 a longitudinal elevation partly in section; and,
Figure 3 a plan illustrating my arrangement for the removal of dredged material
from a barge; and,
Figure 4 is a cross section shewing the apparatus adapted for dredging the bed
of a river.
5
I will first describe the arrangement shewn in Figures 1 to 3. Two pumps a, b
are placed on the dredger A. The suction opening of the mud-pump a has connected
to it a suction tube consisting of separate sections a, a, a. A pipe is connected 1
to the pressure opening of the water-pump band to the water supply tube also
consisting of separate sections c, c', c. This water supply tube opens into the section a²
of the suction-tube of the pump a and terminates in a nozzle c* which can be turned
outside the dredger or be brought over the nozzle a*.
⚫the
pump
b
The tube sections a² and serve as extensions. The tube section a³ is suspended
by a rope running over pulleys to a derrick and its nozzle a is connected to it.
The tube section a' is movably jointed to the tube section a' in order that it may
be easily raised and lowered. In a similar way the tube section c² is movably
suspended from the section c¹.
The operation of lifting the material dredged from a barge B, Figures 1 and 3,
is as follows: The controlling cock d is first placed in the position shewn in the
dotted lines in Figure 3 and the cock d' closed so as to open communication between
6 and the tube sections a², a³ and to shut off the pump & from the tube
sections c, c. The pump 6 is then set in action and. the water drawn up by it
through the tube is forced through the tubes b, c, a³, a³, and the nozzle a which
is resting upon the dredged material in the barge B is let down on to the said
material, whereupon the nozzle a', as the result of the combined action of its own
When
weight and of the stream of water, penetrates into the dredged material.
the nozzle has entered the said material to a sufficient depth the position of the
controlling cock is altered to that shewn in full lines in Figure 3, whereby com-
munication between the pump b and the tube sections c¹³, c is established so that the.
water is directed through the nozzle of the section above the nozzle a. The.
cock dis then opened and the pump a set in action when the stirred up dredged
material will be sucked up by the pump a and conveyed onto the land by means
of the tube a³.
If the apparatus is required to be used for dredging the mud from the bed of a
river, it is only necessary to remove the tube sectious a', a, a, c', c² and to connect
the tubes e, f to the pump a, as shewn in Figure 4. The pump a then acts directly
upon the mud through the tubes e, f and conveys it to the place of collection. The
tube is movably jointed to the tube e so that it can be easily raised and lowered
by means of a rope. The various tube sections may be made up of several pieces
so as to allow of connection, disconnection, lengthening, or shortening being readily
effected in accordance with varying requirements.
The apparatus described can be equally well set up on land instead of on board
a dredger so as to work from the shore.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. An apparatus for raising and discharging dredged material from barges, in
which a nozzle is so combined with a water pump and a mud pump and connected
to a tube for supplying water under pressure and a tube for sucking up mud, each
provided with suitable cocks in such a way that when the cocks are correspondingly
set, the water from the water pump is first driven through the suction pipe of the
mud pump whereupon the nozzle of the suction pipe is lowered by the conjoint
action of the stream of water and the weight of the pipe and then, the position of
the cocks being changed, the water is driven out through. the water supply tube

page_text: whilst the mud pump sucks up and carries off the mud produced by the action of
the jet of water, the sucking action of the mud pump being rendered possible by
the effect of the jet of water from the water pump.
2. The improved apparatus for discharging the contents of dredging barges
S hereinbefore described and illustrated in the accompanying drawing.
Dated the 19th day of August. 1893.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant..