therefor, Partly Applicable to Flushing Sewers.
Year: 1884

page_text: therefor, Partly Applicable to Flushing Sewers.
BENJAMIN HOWARTH THWAITE and BRIERLEY DENHAM HEALEY both of 37
Victoria Street, Liverpool, in the County of Lancaster, Civil Engineers do hereby
declare the nature of our invention for AN IMPROVED METHOD OF REMOVING
SANDBANKS AND APPARATUS THEREFOR PARTLY APPLICABLE TO FLUSHING SEWERS,
to be as follows :—
Our invention consists in the utilisation of great hydraulic pressure for the
removal of sandbanks and the flushing of sewers, such pressuro being generated
by turbines plunger or piston pumps and steam or water motors.
In applying our invention to the removal of sandbanks or similar accumulations
we place the pressure generators on pontoons or other suitable floating vessels or
upon a suitable platform standing on piles or upon firin ground as may be required.
When the generators are placed upon floating vessels the pressure conduits are
provided with telescopic and ball joints to allow for the rise and fall of the tide
and permit continual connection with the main distributing pipe or pipos which
rest upon the material which it is intended to remove.
In order that the requisite pressure may be obtained uniformily at the numerous
nozzles which are provided along each distributing pipo we govern the discharge
by spring or other suitable valvular arrangements adjustable to the pressure
required and attached to each nozzle or between the pressure generators and the
distributors.
The pressure water escaping through the nozzlos scours away the sand or silt and
the telescopic joints allow the distributing pipe or pipes to fall with the altered
surface of the sand as it is continually removed. The nozzles are so placed that
the sand is not only removed but forced simultaneously by all the jets in a direction
leading at about 40 or 50° with the tidal current so that the sand may be carried
out to sea by the ebb tide.
In another application of our invention to the removal of sandbanks or sandbars
we use a vessel of requisito floating capacity which may be fitted up with its own
propeller and in general construction conform to a cassoon but with a rudder, cables,
anchors and other fittings necessary for safe navigation.
The bilges of such cassoon or vessel contain the distributing conduits, rows of
nozzles for efflux of pressure water, and couplings for trailing nozzles. The draught

page_text: of water may be regulated by water ballast in a manner well understood and the
pressure generators may be driven by independent engines or otherwise.
Such cassoon or vessel in cutting a way across a sandbar is ballasted so as to bring
her bilges near to the sand in which case the bilge nozzles are opened to scour
Away the sand.
When the depth of water is too great to allow of the bilges being
brought sufficiently near to the sand then we use the trailing nozzles which aro
suspended from unions attached to the bilges. In using such vessels we set them
head on to the ebb tide and tow them or propel them as may be desired.
In some instances the use of a hose pipe and jet controllable by divers is of
great advantage in removing sand by sustained pressure where the more powerful
apparatus previously described cannot be applied, and a similar contrivanco makes
our invention of easy application for the removal of silt in sewers where the
pressure water is directed by the workman on to the silt without injury to the
Bewer.
In applying our invention to flushing sewers and scouring silt from them when
using water pressure motors for generating the pressure, the waste from generator
flows into a receiver which supplies the pressure cylinder. The overflow from
receiver runs into the sewer and together with the water from pressure jet becomes
the carrier of the dislodged silt so that all the water from street mains which is
used for the pressure generator is used to the best advantage.
therefor, Partly Applicable to Flushing Sewers.
We, BENJAMIN HOWARTH THWAITE Civil Engineer 23 Fountain St Tranmere
Cheshire and BRIERLEY DENHAM HEALEY Civil Engineer 37 Victoria St
Liverpool do hereby declare the nature of our invention for AN IMPROVED
METHOD OF REMOVING BANDBANKS AND APPARATUS THEREFOR PARTLY APPLICABLE
TO FLUSHING SEWERS and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
Our invention consists in the utilisation of great hydraulic pressure for the
removal of sandbanks and the flushing of sewers such pressure being generated by
turbines plunger or piston pumps and steam or water motors.

page_text: In applying our invention to the removal of sandbanks or similar accumulations
we place the pressure generators on pontoons or other suitable floating vessels or
upon a suitable platform, standing on piles or upon firm ground as may be
required.
When the generators are placed upon floating vessels, the pressure conduits are
provided with telescopic and ball joints to allow for the rise and fall of the tide
and permit continual connection with the main distributing pipe or pipes which
rest upon the material it is intended to remove.
In order that the requisite pressure may be obtained uniformly at the numerous
nozzles which are provided along each distributing pipe we govern the discharge
by spring or other suitable valvular arrangements adjustable to the pressure
required and attached to each nozzle or between the pressure generators and
distributors--The pressure water escaping through the nozzles scours away the sand
or silt and the telescopic joints allow the distributing pipe or pipes to fall with the
altered surface of the sand as it is continually removed. The nozzles are so placed
that the sand or silt is not only removed but forced simultaneously by all the jets
in a direction leading at about 40 to 50° with the tidal current so that the sand
may be carried out to sea by the ebb tide Where necessary we support the
horizontal line of pipes containing the nozzles by one or more wheels heavily
constructed and with ball joints and flexible bearings.
In another application of our invention to the removal of sand banks or sand
bars we use a vessel of requisite floating capacity which may be fitted up with its
propeller and in general construction conform to a caisson but with a rudder cables
anchors and other fittings necessary for safe navigation.
The bilges of such caisson or vessel contain the distributing conduits, rows of
nozzles for efflux of pressure water and couplings for trailing nozzles.
The draught of water may be regulated by water ballast in a manner well
understood, and the pressure generators may be driven by independent engines or
otherwise.
Such caisson or vessel in cutting a way across a sandbank is ballasted so as to
bring her bilges near to the sand in which case the bilge nozzles are opened to
scour away the sand when the depth of water is too great to allow of the bilges
being brought sufficiently near to the sand then we use the trailing nozzles which
are suspended from unions attached to the bilges.
•
In using such vessels we set them head on to the ebb tide and tow them or propel
them by hydraulic propulsion as may be desired.
In some instances the use of a hose pipe and jet controllable by divers is of
great advantage in removing sand by sustained pressure when the more powerful
apparatus previously described cannot be applied and a similar contrivance makes
our invention of easy application for the removal of silt in sewers where the
pressure water is directed by the workmen on to the silt without injury to the
sewer.
In applying our invention to flushing sewers and scouring silt from them when
using water pressure motors for generating the pressure, the waste from generator
flows into a receiver which supplies the pressure cylinder.
The overflow from receiver runs into the sewer and together with the water
from pressure jet becomes the carrier of the dislodged silt so that all the water
from street mains which is used for the pressure generator is used to the best
advantage.
The accompanying drawings which are intended to form part of this specification
shew the application of our invention when applied for the removal of silt
accumulations, in mid-stream and during the maximum botton velocity of the ebb
tide but we wish it to be understood that we do not confine ourselves to the
particular arrangement shewn. Fig. 1 is a longitudinal section, shewing hollow
trunnion arrangement of supporting water pressure telescopic pipes or tubes,
Fig. 2 is a midship section shewing trunnion arrangement,

page_text: Fig. 3 is a detail of telescopic pipes shewing ball joint section of nozzle jet
distributing pipe, and manner of supporting the distributing pipe.
a. is the steam generator.
in the tushina
f. the guide for steadying movement of trunnion arm g.
h. the telescopic water pressure pipes.
i. the horizontal water pressure distributing pipes.
j. the ball joints.
k. valvular water jet nozzles.
Z. elevating lowering trailing and anchoring chains.
m. wheels supporting horizontal distributing pipe..
n. vessel caisson or pontoon.
Having now particularly described and ascertained the nature of our said
Invention we wish it to be understood that we do not claim the use of water
under pressure for the removal of silt as such a method was applied by M. Chas.
Bergeron in the Boulogne Harbour, but what we claim is as follows
1st The distribution of the water pressure for the purposes of our invention or
the removal of silt or sand accumulations by means of telescopic and ball jointed
tubes or pipes in the manner herein substantially described.
2nd The utilisation of valvular nozzles for governing the discharge and pressure
of the water through the nozzles or jet pipes.
3rd The arrangement of caissons or vessels containing discharge nozzles sub-
stantially as described.
4th The use of water pressure in the manner substantially as herein described for
flushing sewers and for diving operations.
5th The general arrangement as shewn by drawings, and substantially as
'described, for supplying telescopic cylinders with water pressure by means of hollow
'trunnions with circular guide arms.