Improvements in Centrifugal Pumps, especially those used in Dredging Operations.
Year: 1899

page_text: Date of Application, 24th Apr., 1899-Accepted, 27th May, 1899
Improvements in Centrifugal Pumps, especially those used in
Dredging Operations.
I, RICHARD PICKUP PARK, of Morrisons, in the Colony of Victoria, Engineer,
do hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:
This invention has been devised for the purpose of overcoming certain defects
in centrifugal pumps where water containing frictional matter such as sludge,
clay, gravel, sand or the like earths, or gritty matters has to be passed through,
or operated upon, by the pump.
In dredging operations, that is to say where auriferous earths are drawn into,
and discharged from a centrifugal pump, it has been found that a portion of such
earth finds its way between the runner and the casing of the pump and enters into
the bearings of the said pump.
Now by the employment of the apparatus embodying my invention the pump
during its working automatically prevents the proceedure of frictional or undesirable
matter to the bearings as aforesaid.
My invention may be applied to existing pumps, but in practice I prefer the
pump to be specially constructed in accordance with my improvements.
My invention consists in increasing the diameter of the sides only of the runner
by the addition of circular flanges to existing pumps, or when the pump is
specially constructed to embody my invention, then by making the sides of the
runner of a larger diameter than they would have been under ordinary circum-
stances, and also by the addition of vanes or blades to the sides (so increased in
diameter) of the said runner in such a manner that they constitute independent or
synchronously working pumps; the said vanes or blades being calculated to pro-
duce enhanced pressure or pumping efficiency to that pressure or efficiency exist-
ing or ascertained at the peripheral delivery exit of the runner proper.
In order to make my invention clear reference may be made to the accompany-
ing drawings in which:-
Figure 1 is intended to represent the runner of a centrifugal pump used for
dredging and having my improvements attached thereto.
Figure 2 is a front view of same whilst
Figures 3 and 4 show how the circular flanges and vanes may be added to an
existing pump.
2
In these drawings "A" represents the runner of a centrifugal pump, "B" being
the casing thereof and C" the shaft running in its bearings at "D"
"E" "E" are the added flanges hereinbefore referred to and "A2" are the
angle irons by which said flanges may be added to an existing runner (Figures 3
"F"F" are the external vanes or blades extending beyond the
and 4).

page_text: diameter of the runner but not exceeding the diameter of the flange "E." These
vanes or blades F""F" being of greater rotatory diameter than the runner
proper "A" of the pump produce during their rotation a greater pressure between
the casing "B" and the runner " A than that produced at or in the peripheral
delivery line of the runner "A" at that line of diameter where the flanges "E"
are added.
This increase of pressure in such locality prevents or obviates the ingress between
the said runner A and casing "B" of frictional or undesirable matters to the
shaft Cor bearings at "D." It will be understood by any person skilled in
working such pumps that the greater the diameter of the runner the greater the
pressure will be near its periphery with a given number of revolutions per minute
and that the pressure being greater between the casing "B" and the runner
the gravel, sand, clay or such other frictional or undesirable matter cannot find
its way down from the peripheral delivery exit of the runner proper A” to the
said shaft or bearings.
66
A'
93
The annular channel A" around the periphery of the runner proper, that
is to say inside the added flanges "E" will be free or open for the facile escape
of the earths or sludgy matter being passed through the pump during its operation
for dredging purposes.
33
I would have it understood that I may employ the added flange "E" on one side
only of the runner "A" when a centrifugal pump of a correspondingly different
pattern is to be used, and that I do not confine myself to the depth or length of
the said vanes or blades "F""F," as their measurements may be modified for
local requirements without departing from the nature of my invention, but I would
point out that the said vanes or blades "F must of necessity exceed in length the
line of diameter on the runner proper at its point of delivery so as to project above
such line of diameter. I also desire to state that such vanes or blades should in
length preferably not exceed the outer diameter line of my added flanges "E"
that is to say in practice I prefer such vanes or blades to terminate at the peripheral
line E" of the said flanges
EE."
"
66
The vanes or blades "F"
"F" also are devised by me to overcome the thrust
of the pump; that is to say, by increasing the number of the side vanes or
blades F" "F" on one side over that of the other of the runner, so that during
rotation the increased vacuum owing to the increased number of vanes on one
side will control the thrust occurring in such pumps in the direction of the suction
pipe.
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
1. In centrifugal pumps-Vanes or blades whose diameters are greater than
the diameter of the runner at its point of delivery, added to or constructed on the
side of the runner substantially as and for the purposes set forth.
2. In centrifugal pumps :- Vanes or blades added to or constructed on the side
or sides of a runner in differential number or efficiency as regards one side to the
other of the said runner for controlling the thrust caused by the action of the
pump substantially as herein before set forth.
3. In centrifugal pumps :-In combination, flanges as "E"-"E" with vanes
or blades """F" and a runner substantially as and for the purposes set
forth.
4. In centrifugal pumps :-In combination a disc or discs whose diameter or
diameters exceeds the diameter of the runner at its point of delivery with vanes or
blades mounted upon said disc or discs substantially as and for the purposes set
forth, and illustrated in the accompanying drawings.
5. In centrifugal pumps: -The general combination and arrangement of the

page_text: several parts embodying my invention substantially as and for the purposes set
forth and as illustrated on the accompanying drawings.
Dated this 24th day of April 1899.
BOULT & WADE,
Agents for the Applicant.