Note: Descriptions are shown in the official language in which they were submitted.
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 1 -
SLURRY PUMP AND COMPONENTS THEREFOR
Technical Field
[0001] This disclosure relates generally to centrifugal slurry pumps
and
components or parts for use in such pumps. The components or parts of
particular interest
are pump impellers, and pump liners including main liners as well as side
liners. Slurries
are usually a mixture of liquid and particulate solids, and are commonly found
in minerals
processing, sand and gravel and/or dredging industry.
Background Art
[0002] In one typical form centrifugal slurry pumps generally
comprise an outer
housing which encases an inner liner. The liner may include a main liner
(sometimes
referred to as a volute) and two side liners. The liners are generally formed
from hard
metals or elastomers. The liner is configured with a pumping chamber therein.
The main
liner has openings on opposite sides thereof one of which provides an inlet to
the pumping
chamber. A discharge outlet is provided at the periphery of the main liner and
may for
example extend generally in a tangential direction. An impeller is mounted
within the
pumping chamber for rotation about an axis of rotation. A drive shaft is
operatively
connected to the impeller for causing rotation thereof. The drive shaft is
disposed to one
side of the outer housing and main liner. This is often referred to as the
rear or back side
of the pump. An inlet is disposed to the other side of the outer housing and
liner. This is
often referred to as the front side of the pump. The inlet is typically
coaxial with the
impeller rotation axis. The pump further includes a discharge outlet typically
located at the
periphery of the main liner and outer housing.
[0003] One of the side liners is at the front side of the pump and is
often referred to
as the front liner, front liner suction plate or throatbrush. The front liner
provides for the
pump inlet and may typically comprise a sidewall which extends laterally with
respect to
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 2 -
the impeller rotation axis and an inlet conduit which extends from the side
wall the inlet
conduit being arranged generally co-axially with the impeller rotation axis.
In particular
applications where the pump is of the type referred to as a horizontal slurry
pump the inlet
conduit is disposed generally horizontally when in use.
[0004]
The other of the side liners is at the rear or back side of the pump and is
often referred to as the back side liner or frame plate liner insert. The back
side liner
comprises a generally circular disc-like body arranged such that when in use
one side of
thereof faces the impeller and the other side faces a seal assembly which may
comprise a
seal housing and seal chamber. The seal assembly may include a main seal which
may be
in the form of a stuffing box. The back side liner has a central passageway
through which
the drive shaft can pass.
[0005]
The impeller typically includes a hub to which a drive shaft is operatively
connected and at least one shroud. Pumping vanes are provided on one side of
the shroud
with discharge passageways between adjacent pumping vanes. In one form of
impeller,
two shrouds are provided with pumping vanes being disposed therebetween. The
pumping
vanes include a leading edge portion in the region of the inlet and a trailing
edge portion in
the region of the outer peripheral edge of the or each shroud. The impeller
further includes
an eye portion or nose which extends from one side of a shroud and is adjacent
the
pumping vanes leading edges and generally in the region of the impeller
rotation axis. In
one form, when assembled the hub is at least partially disposed within the
central
passageway of the back side liner.
[0006] Because
of the abrasive nature of slurries the pump, and in particular the
pump components such as the pump impeller and pump liner are subjected to
extreme
wear which leads to a significant reduction in the operational life of these
components.
[0007]
In operation slurry enters the impeller in the region of the centre or eye,
and
is then flung out to the periphery of the impeller and into the main pump
liner. Because
there is a pressure difference between the liner and the eye, there is a
tendency for the
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 3 -
slurry to try and migrate into gaps which are between the side-liners and the
impeller,
resulting in high wear on the side-liners.
[0008]
In order to reduce the driving pressure on the slurry in the gaps, as well as
create a centrifugal field to expel particles, slurry pumps often have
auxiliary or expelling
vanes on the front shroud of the impeller. Auxiliary or expelling vanes may
also be
provided on the back shroud. The expelling vanes rotate the slurry in the gaps
creating a
centrifugal field and thus reducing the driving pressure for the returning
flow, reducing the
flow velocity and thus the wear on the side-liner. The purpose of these
auxiliary vanes is
to reduce flow re-circulation through the gap. These auxiliary vanes also
reduce the influx
of relatively large solid particles in these gaps. Much of the wear on the
side-liners is a
result of the flow generated by the rotating auxiliary vanes. In particular,
there is wear
from the tip or outer edge of the auxiliary vanes due to the creation of fluid
vortices and
entrained particles.
[0009]
The rotating impeller causes slurry in the gaps between the impeller shroud
and the side liners to rotate thereby creating vortices. The slurry in these
gaps tend to
rotate more slowly then the impeller. At the rear or back side of the pump the
rotating
slurry is rotating as it enters the seal chamber. This can cause wear on the
seal which as
mentioned earlier may be in the form of a stuffing box. Furthermore, the
pressure in the
seal chamber can become unstable.
[0010]
The main liner is subjected to wear as a result of the turbulence in the
pumping chamber which causes a rough flow pattern as the slurry passes through
the main
liner.
[0011]
In horizontal slurry pumps larger and denser particulates or solids entering
the inlet conduit of the front side liner tend to gravitate towards a lower
region of the
conduit. This can cause problems for the impeller as a result of greater
concentration of
solids or particulates because of the velocity and flow patterns generated.
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 4 -
Summary of the Disclosure
[0012]
In a first aspect embodiments are disclosed of a centrifugal pump impeller
for use in a slurry pump which comprises a front shroud and a back shroud, the
front and
back shrouds each having an inner face and respectively the inner faces facing
one another,
the front and back shrouds and also having respective back faces and, the
front shroud has
an inlet opening through which slurry is delivered to an interior region of
the impeller, the
impeller is mounted for rotation about rotation axis, the impeller further
comprises a
plurality of pumping vanes within the interior region the pumping vanes
extending
between the inner faces and of the front and back shrouds and, each of the
pumping vanes
having a leading edge in the region of the rotation axis, the vanes also have
trailing edges
which are disposed outwardly from the leading edges, the pumping vanes being
spaced
apart from another so as to provide passageways between adjacent pumping
vanes, the
impeller further including a hub extending from the outer face of the back
shroud, the hub
being coaxial with axis and adapted to be connected to a drive shaft, and a
nose or eye
portion having a generally dome shaped profile with an apex in the region of
the axis,
characterised in that the impeller further includes two raised formations or
ribs on the nose
or eye portion, one formation or rib extending from the leading edge of
pumping vane in
the region where the leading edge is adjacent the back shroud over the nose or
eye portion
and through the apex to the leading edge of oppositely disposed pumping vane
in the
region where the edge is adjacent the back shroud, and the other formation or
rib extending
from the leading edge of pumping vane in the region where the leading edge is
adjacent the
back shroud over the nose or eye portion and through the apex to the leading
edge of
pumping vane in the region where the leading edge is adjacent the back shroud.
[0013]
In certain embodiments the formations or ribs and cross in the region of the
apex at approximately right angles with respect to one another. So as to
provide for four
auxiliary passageways or zones each passageway or zone being disposed between
respective adjacent formations or ribs.
[0014]
In a second aspect embodiments are disclosed of a main pump liner for use
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 5 -
in a slurry pump comprising: a main body which includes a pump chamber section
having
opposed sides each having an opening therein with a major axis extending
between the
sides; the pump chamber section having a pumping chamber therein, the pumping
chamber
having an inner surface which includes a curved peripheral surface portion and
side surface
portions one on either side of the peripheral surface portion and extending
from the
peripheral surface portion to a respective one of the openings; the main body
further
including a discharge outlet section having a discharge passageway therein
with an inner
surface which is in fluid communication with the pumping chamber, the
discharge
passageway being of a generally linear configuration with a linear axis which
extends
generally tangentially from the pumping chamber and terminates at a discharge
outlet port
characterised in that the pump liner comprises a continuous formation
projecting from the
inner surface of the discharge passageway and the peripheral surface portion
of the
pumping chamber the formation having a first end within the discharge
passageway and
spaced from the outlet port and a second end in the pumping chamber which
terminates
before a lateral axis so as to be spaced therefrom, the lateral axis extending
through the
major axis and being parallel to the linear axis.
[0015] In certain embodiments the formation when viewed in cross-
section
comprises a segment of the curved peripheral surface of the pumping chamber
and the
inner surface of the discharge passageway.
[0016] In certain embodiments that the cross-sectional area of the
segment is up to
10% of the cross-sectional area of the discharge passageway.
[0017] In certain embodiments the cross-sectional area of the segment is
about
1.5% of the cross-sectional area of the discharge passageway.
[0018] In certain embodiments the formation is cast with the side
liner.
[0019] In certain embodiments the formation is disposed in a plane which is
at
right angles to the major axis and centrally positioned with respect to the
inner surface of
the pumping chamber and discharge passageway.
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 6 -
[0020]
In a third aspect embodiments are disclosed of a front side liner for use in a
slurry pump comprising a main body having an inner side and an outer side, the
side liner
further comprising an intake section which extends outwardly away from outer
side of the
main body, the intake section including an intake passageway extending through
the intake
section having an entry end and an exit end, the intake passageway having an
inner surface
which is generally circular in cross-section, characterised in that the side
liner further
includes a guide formation on the inner surface of the intake passageway, the
guide
formation extending from the entry end of the intake passageway to the exit
end and
including a leading end portion at the entry end of passageway and a trailing
end portion at
the exit end, the guide formation further including a guide surface extending
between the
leading end portion and the trailing end portion.
[0021]
In certain embodiments when the side liner is in use the central axis (P-P) is
generally horizontally disposed and the guide formation is on a lowermost
region of the
inner surface of the intake passageway.
[0022]
In certain embodiments the side liner further includes one or more first
guides on a first portion of the inner surface of the passageway for directing
fluid passing
through the intake passageway so that in use said fluid leaves the exit end at
the first
portion with a first exit angle which is inclined relative to the central axis
(P-P), and a
second portion of the inner surface of the intake passageway which includes
one or more
second guides thereon for directing fluid passing through the intake
passageway so that in
use said fluid leaves the exit end at the second portion with a second exit
angle which is
inclined relative to the central axis, the second exit angle being greater
than the first exit
angle the formation being disposed between adjacent guides in the second
portion. In use,
when the central axis (P-P) is horizontally disposed, the second guides are
below the
central axis (P-P) with the formation being in a lowermost region between
adjacent second
guides.
[0023]
In certain embodiments the guide formation, when viewed in cross-section
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 7 -
comprises a segment of the curved inner surface of the intake passageway, the
guide
surface when viewed in cross-section comprises the chord of the segment, the
plane of the
guide surface being substantially parallel with a central axis of the
passageway which
extends between the ends thereof.
[0024]
In certain embodiments the leading end portion of the guide formation has
an inclined or ramped surface which extends from the inner surface of the
passageway to
the guide surface of the guide formation and the trailing end portion has an
inclined or
ramped surface which extends from the guide surface to the inner surface of
the
passageway, the angle of inclination of inclined surface is less than the
angle of inclination
of inclined surface.
[0025]
In a fourth aspect embodiments are disclosed of a back side liner for use in
a slurry pump which comprises a main body which includes a generally annular
disc
shaped wall having a front face and a rear face with a passageway extending
through the
main body from the front face to the rear face of the wall in the direction of
primary axis
the passageway having a peripheral wall characterised in that the side liner
further
comprises a plurality of vanes on the rear face, the vanes extending in a
generally radial
fashion with respect to the primary axis and including an inner edge and an
outer edge, the
inner edge being adjacent the peripheral wall of the passageway.
[0026]
In certain embodiments the rear face has a recess therein, the recess being
stepped inwardly towards the front face, the recess having a recessed surface
which is
disposed around passageway and includes an outer peripheral wall, the
plurality of vanes
been disposed within the recess, and extending in a radial fashion from the
outer peripheral
wall towards the passageway. In certain embodiments the recess wherein an
outer
peripheral wall which is of a wave like configuration comprising alternating
crests and
valleys, a plurality of vanes being disposed within the recess, the vanes
extending in a
radial fashion from the outer peripheral wall towards the passageway
terminating at the
periphery of the passageway, the vanes being arranged in spaced apart fashion
around the
passageway.
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 8 -
[0027] In certain embodiments the vanes comprise a first group and a
second
group, the first group being longer than the second group, the first group
extending from
the crests and second group extending from the valleys. In certain embodiments
the vanes
include an upper surface which tapers inwardly towards the inner edge thereof.
[0028] In a fifth aspect embodiments are disclosed of a combination
of a pump
impeller and front side liner both of which are in the form of the embodiments
described
above in the summary of the disclosure.
[0029] In a sixth aspect embodiments are disclosed of an assembly for a
slurry
pump assembly comprising a main liner, a front liner, a back liner and an
impeller each of
which is in the form of the embodiments described above in the summary of the
disclosure.
[0030] Other aspects, features, and advantages will become apparent
from the
following detailed description when taken in conjunction with the accompanying
drawings,
which are a part of this disclosure and which illustrate, by way of example,
principles of
inventions disclosed.
Brief Description of the Drawings
[0031] Notwithstanding any other forms which may fall within the
scope of the
method and apparatus as set forth in the Summary, specific embodiments of the
method
and apparatus will now be described, by way of example, and with reference to
the
accompanying drawings in which:
[0032] Figures 1 and 2 are schematic partial cross-sectional side
elevations of
typical pumps;
[0033] Figures 3 and 4 are isometric views of a main liner;
[0034] Figures 5 and 6 are sectional views of a main liner, according
to one
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 9 -
embodiment of the present disclosure with one view showing a part thereof in
dashed line;
[0035] Figure 7 is a sectional view of the main liner shown in figure
5 taken along
the line A-A;
[0036] Figure 8 is a further sectional view of the main liner shown
in figures 5 and
6;
[0037] Figure 9 is an isometric view of a front side liner according
to one
embodiment;
[0038] Figure 10 is a sectional view of the front side liner shown in
figure 9;
[0039] Figures 11 and 12 are end elevations of the side liners shown
in figures 9
and 10 viewed from opposite sides;
[0040] Figures 13 and 14 are isometric views of the side liners shown
in figures 9
to 12 viewed from opposite sides;
[0041] Figure 15 is an enlarged view of part of front side liner;
[0042] Figures 16 to 20 are various views of a front side liner
according to another
embodiment;
[0043] Figure 21 is an isometric view of a rear side liner according to one
embodiment;
[0044] Figure 22 is an end elevation of the rear side liner shown in
figure 21;
[0045] Figure 23 is a sectional view of the rear side liner shown in
figures 21 and
22;
[0046] Figure 24 is an isometric view of an impeller according to one
embodiment;
[0047] Figure 25 is an end elevation of the impeller shown in figure 24;
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 10 -
[0048] Figure 26 is a sectional view of the impeller shown in figures
24 and 25;
[0049] Figure 27 is an exploded partial sectional isometric view of
the impeller
shown in figures 24 to 26 and the front side liner shown in figures 9 to 14;
[0050] Figure 28 is an end elevation of an assembly comprising the
liners shown in
figures 6 to 23 and the impeller shown in figures 24 to 26;
[0051] Figures 29 and 30 are views partially in section of an assembly; and
[0052] Figures 31 and 32 are sectional side views of the assembly
shown in figures
28 to 31 together with a typical seal.
Detailed Description of Specific Embodiments
[0053] Referring to Figures 1 and 2 of the drawings, there is
generally illustrated
slurry pump apparatus 100 comprising a pump 10 and pump housing support in the
form of
a pedestal or base 112 (only partially shown) to which the pump 10 is mounted.
Pedestals
are also referred to in the pump industry as frames. The pump 10 generally
comprises an
outer casing 22 that is formed from two side casing parts or sections 23, 24
(sometimes
also known as the frame plate and the cover plate) which are joined together
about the
periphery of the two side casings sections 23, 24. The pump 10 is formed with
side
openings one of which is an inlet hole 28 there further being a discharge
outlet hole 29.
The arrangement is such that when in use in a process plant, the pump is
connected by
piping to the inlet hole 28 and to the outlet hole 29, to facilitate for
example pumping of a
mineral slurry.
[0054] The pump 10 further comprises a pump inner liner 11 arranged
within the
outer casing 22 and which includes a main liner 12 and two side liners 14, 30.
The side
liner (or back liner) 14 is located nearer the rear side of the pump 10 (that
is, nearest to the
pedestal or base 112), and the other side liner (or front liner) 30 is located
nearer the front
side of the pump.
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 11 -
[0055]
As shown in Figures 1 and 2 the two side casing parts 23, 24 of the outer
casing 22 are joined together by bolts 27 located about the periphery of the
casing parts 23,
24 when the pump is assembled for use. In some embodiments the main liner 12
can also
be comprised of two separate parts which are disposed within the side casing
parts 23, 24
and brought together to form a single main liner, although in the example
shown in figure
1 the main liner 12 is made in one-piece, shaped similar to a car tyre. The
liner 11 may be
made of materials such as rubber, elastomer or of metal.
[0056] When the
pump is assembled, the side openings in the main liner 12 are
filled by or receive the two side liners 14, 30 to form a continuously-lined
pumping
chamber 42 disposed within the pump outer casing 22. A seal comprising a seal
chamber
housing 114 and cover plate 115 encloses the side liner (or back liner) 14 and
is arranged
to seal the space or seal chamber 118 between drive shaft 116 and the pedestal
or base 112
to prevent leakage from the back area of the outer casing 22. The seal chamber
housing
takes the form of a circular disc section and an annular section with a
central bore, and is
known in one arrangement as a stuffing box 117. The stuffing box 117 is
arranged
adjacent to the side liner 14 and extends between the pedestal 112 and a shaft
sleeve and
packing that surrounds the shaft 116.
[0057]
As shown in figures 1 and 2 an impeller 40 is positioned within the main
liner 12 and is mounted or operatively connected to the drive shaft 116 which
is adapted to
rotate about a rotation axis X-X. A motor drive (not shown) is normally
attached by
pulleys to an exposed end of the shaft 116, in the region behind the pedestal
or base 112.
The rotation of the impeller 40 causes the fluid (or solid-liquid mixture)
being pumped to
pass from a pipe which is connected to the inlet hole through the pumping
chamber 42
which is within the main liner 12 and the side liners 14, 30 and then out of
the pump via
the discharge outlet hole.
[0058] As shown,
the front liner 30 (or throatbrush) includes a cylindrically-shaped
delivery section 32 through which slurry enters the pumping chamber 42 when
the pump is
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 12 -
in use. The delivery section 32 has a passage 33 therein with a first,
outermost end 34
operatively connectable to a feed pipe (not shown) and a second, innermost end
35
adjacent the chamber 42. The front liner 30 further includes a side wall
section 15 which
mates in use with main liner 12 to form and enclose the chamber 42, the side
wall section
15 having an inner face. In the embodiment of figure 1 the second end 35 of
the front liner
30 has a raised lip 38 thereat, which is arranged in a close facing
relationship with the
impeller 40 when in an assembled position. The back liner 14 comprises a disc-
like body
having an outer edge which mates with the main liner and an inner face.
[0059] The
impeller 40 includes a hub 41 from which a plurality of
circumferentially spaced pumping vanes 43 extend. An eye portion 47 extends
forwardly
from the hub 41 towards the passage 33 in the front liner 30. The impeller 40
further
includes a front shroud 50 and a back shroud 51, the vanes being disposed and
extending
therebetween and an impeller inlet 48. The hub 41 extends from the back liner
14. In
figure 2 the shrouds are arranged in planes which are generally at right
angles to the
rotation axis. In figure 1 the front shroud is inclined with respect to the
axis.
[0060]
The front and back shrouds include an inner face, an outer face and a
peripheral edge portion. The front shroud includes an inlet, and the vanes 43
extend
between the inner faces of the shrouds. The shrouds are generally circular or
disc-shaped
when viewed in elevation; that is in the direction of rotation axis X-X
(figure 1).
[0061]
As illustrated in figure 2, each shroud has a plurality of auxiliary or
expelling vanes on the outer faces thereof, there being a first group of
auxiliary vanes 60
on the outer face of the front shroud and a second group of auxiliary vanes 61
on the outer
face of the back shroud. In the embodiment of figure 1 there are auxiliary
vanes on the
front shroud only.
[0062]
With reference to Figures 3 to 8 there is illustrated a main slurry pump liner
120 which comprises a main body 122 which includes a pump chamber section 124
having
opposed sides 137, 138 (figure 8) each having an opening 139, 140 therein
(figure 8) with
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 13 -
a major axis Q-Q extending between the sides (figures 5 and 6). The pump
chamber
section 124 has a pumping chamber 142 therein with an inner surface 144 which
includes a
peripheral surface portion 145 and side surface portions 146, 147 one on
either side of the
peripheral surface portion and extending from the peripheral surface portion
to a respective
one of the openings. The main body 122 further includes a discharge outlet
section 150
having a discharge passageway 151 with an inner surface 152 which is in fluid
communication with the pumping chamber. The discharge passageway is of a
generally
linear configuration with a linear axis Y-Y which extends generally
tangentially from the
pumping chamber 142 and terminates at a discharge outlet port 154.
[0063]
The liner is provided with a continuous formation 156 on or projecting
from the inner surface 152 of the discharge passageway 151 and the peripheral
surface
portion 145 of the pumping chamber 142. As best seen in figure 5 the formation
156 has a
first or trailing end 157 within the discharge passageway 151 and spaced from
the outlet
port 154 and a second or leading end 158 in the pumping chamber 142 which
terminates
before a lateral axis Z-Z so as to be spaced therefrom. The lateral axis Z-Z
extends
through the major axis Q-Q and is parallel to the linear axis Y-Y.
[0064]
As illustrated the formation 156 is disposed in the region of an outermost
part of the peripheral surface portion 145 of pumping chamber inner surface
144 and inner
surface 152 of the discharge passageway 151. As shown, that part of the
formation 156 in
the discharge passageway is generally straight or linear and that part in the
pumping
chamber is generally curved or arcuate.
[0065] As best
shown in figure 8 the formation 156 when viewed in cross-section
comprises a segment 160 of the inner surfaces 144 and 152 of pumping chamber
and
discharge passageway. The chord 162 of the segment 160 forms an outer surface
159 of
the formation 156. The outer surface 159 is generally flat or planar. The
first and second
ends 157 and 158 of the formation 156 are inclined with respect to the outer
surface 159
from the inner surfaces 144 and 152. In the embodiment illustrated the cross-
sectional area
of the segment 160 is about 1.5% of the cross-sectional area of the discharge
opening.
When the slurry pump is operating the formation within the main liner tends to
split the
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 14 -
flow in the pumping chamber and discharge passageway. This leads to a
significant
reduction in turbulence effectively smoothing the flow pattern and increasing
wear life.
[0066]
Referring to Figures 9 to 15 there is illustrated a slurry pump side liner 200
which is a front liner for a pump the side liner 200 comprising a main body
202 having an
inner side 204 and an outer side 206. In an assembled position in a pump the
inner side
204 faces the pump impeller, as illustrated in figures 27 to 32. As clearly
illustrated in
figure 10 the side liner 200 further includes an intake section 210 which
extends outwardly
away from outer side 206 of the main body 202. The intake section 210 includes
an intake
passageway 212 extending through the intake section 210 having an entry end
214 and an
exit end 216. The intake passageway 212 has an inner surface 218 which is
generally
circular in cross-section. In use the intake section 210 is generally
horizontally disposed.
[0067]
The side liner 200 further includes a guide formation 220 on the inner
surface 218 of the intake passageway 212. The guide formation 220 extends from
the
entry end 214 of the intake passageway 212 to the exit end 216. The guide
formation 220
includes a leading end portion 222 at the entry end 214 of passageway 212 and
a trailing
end portion 224 at the exit end 216. The guide formation 220 further includes
a guide
surface 226 extending between the leading end portion 222 and the trailing end
portion
224.
[0068]
As shown more clearly in figure 15 the guide formation, when viewed in
cross-section comprises a segment 227 of the curved inner surface 218 of the
lowermost
portion of the intake passageway 218. The guide surface 226 when viewed in
cross-
section comprises the chord 228 of the segment 227. The plane of the guide
surface 226 is
substantially parallel with a central axis P-P of the passageway 212 which
extends between
the ends thereof. The leading end portion 222 of the guide formation 220 has
an inclined
or ramped surface 223 which extends from the inner surface 218 of the
passageway 212 to
the guide surface 226 of the guide formation 220. The trailing end portion 224
has an
inclined or ramped surface 225 which extends from the guide surface 226 to the
inner
surface of the passageway. The angle of inclination of inclined surface 223 is
less than the
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 15 -
angle of inclination of inclined surface 225.
[0069]
Another embodiment of a side liner is illustrated in figures 16 to 20. The
structure of this side liner is substantially the same as that described with
reference to
figures 8 to 15. This embodiment differs from the earlier embodiment in that
the inner
surface of the passageway also includes a first group of guides 230 on a first
portion of the
inner surface of the passageway and a second group of guides 232 on a second
portion of
the passageway inner surface. The formation 220 is disposed between adjacent
guides 232
which, in use, is the lowermost section of the passageway. The arrangement is
such that,
in use, said fluid leaves an exit end of the first group of guides 230 with a
first exit angle
which is inclined relative to the central axis and fluid leaves an exit end of
the second
group of guides 232 with a second exit angle which is inclined relative to the
central axis,
the second exit angle being greater than the first exit angle. Full details of
this structure is
described in European Patent Application 11750076.9 the contents of which are
incorporated herein by cross-reference. The cross-sectional area of the
segment 227 is from
about 0.5% to about 1.5% of the cross-sectional area of the intake passageway
212. In a
preferred form, and in the embodiment illustrated, the cross-sectional area of
the segment
227 is about 1.0% of the cross sectional area of the intake passageway 212.
[0070]
Referring to figures 21 to 23 of the drawings there is shown a slurry pump
side liner 300 (often referred to as a back side liner) which comprises a main
body 302
which includes a generally annular disc shaped wall 304 having a front face
306 and a rear
face 308 with a passageway 310 extending through the main body 302 from the
front face
306 to the rear face 308 of the wall 304 in the direction of primary axis P-P.
As shown the
passageway 310 has an inner surface 311 which is slightly frusto-conical in
shape. The
wall 304 has an outer peripheral rim 314 with a peripheral surface 315. The
front face 306
is generally planar.
[0071]
The rear face 308 has a series of bosses 317 for receiving fasteners which
secure the side liner 300 to the pump outer casing. The rear face 308 has a
recess section
316, the recess section 316 being stepped inwardly towards the front face 306.
The recess
section 316 has a recess surface 318 which is disposed around passageway 310.
The
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 16 -
recess 316 has an outer peripheral wall 320 which is of a wave like
configuration
comprising alternating crests 322 and valleys 324.
[0072] A
plurality of vanes 330 are disposed within the recess, the vanes extending
in a generally radial fashion from the outer peripheral wall towards the
passageway 310.
The recess 316 has an outer peripheral wall 320 which is of a wave like
configuration
comprising alternating crests 322 and valleys 324.
[0073]
As shown the vanes 330 have an inner edge 336 which terminates at the
periphery of the passageway 310 and an outer edge 337 which is at the wall
320. The
vanes 330 are arranged in spaced apart fashion around the passageway 310. As
shown
there are groups of vanes identified as a first group 332 and a second group
334. The first
group 332 are longer than the second group 334. The first group extend from
the crests
322 and second group extend from the valleys 324. The vanes separate the
recess into a
series of zones. The vanes 330 have an upper or outer surface 331 which is
tapered
inwardly from the outer edge 337 towards the inner edge thereof. The outer
edge of the
vanes is at a height which approximates the depth of the recess at the wall
320.
[0074]
Referring to figures 24 to 27 of the drawings there is shown a centrifugal
pump impeller 400 which comprises a front shroud 401 and a back shroud 402.
The front
and back shrouds each have an inner face 403 and 404 (figure 27) respectively
the inner
faces facing one another. The front and back shrouds 401 and 402 also have
respective
back faces 405 and 406. The front shroud has an inlet opening 450 through
which slurry is
delivered to an interior region 455 of the impeller 400. The impeller 400 is
mounted for
rotation about rotation axis B-B (figures 24 and 29).
[0075]
The impeller 400 further comprises a plurality of pumping vanes 410, 411,
412, 413 (figure 26) within the interior region 455 the pumping vanes
extending between
the inner faces 403 and 404 of the front and back shrouds 401 and 402. Each of
the
pumping vanes has a leading edge 420, 421, 422, 423 in the region of the
rotation axis B-
B. The vanes also have trailing edges (not shown) which are disposed outwardly
from the
leading edges. Each pumping vane 410, 411, 412, 413 is generally arcuate in
cross-
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 17 -
section and includes an inner leading edge 420, 421, 422, 423 and an outer
trailing edge
424, 425, 426, 427 and opposed faces 445 and 446, the side face 445 being a
pumping or
pressure side which is the leading face with respect to the direction of
rotation of the
impeller. The vanes are normally referred to as backward-curving vanes when
viewed with
the direction of rotation. The pumping vanes are spaced apart from another so
as to
provide passageways 414 between adjacent pumping vanes.
[0076]
The impeller 400 further includes a hub 415 extending from the outer face
of the back shroud. The hub is coaxial with axis B-B is adapted to be
connected to a drive
shaft. There is further provided a nose or eye portion 430 having a generally
dome shaped
profile with an apex 440 in the region of the axis B-B.
[0077]
The impeller 400 further includes two raised formations or ribs 435, 436 on
the nose or eye portion 430. Formation or rib 435 extends from the leading
edge 420 of
pumping vane 410 in the region where the leading edge is adjacent the back
shroud 402
over the nose or eye portion and through the apex 440 to the leading edge 422
of
oppositely disposed pumping vane 412 in the region where the edge is adjacent
the back
shroud 402. Similarly, formation or rib 436 extends from the leading edge 421
of pumping
vane 411 in the region where the leading edge is adjacent the back shroud 402
over the
nose or eye portion and through the apex 440 to the leading edge 423 of
pumping vane 413
in the region where the leading edge is adjacent the back shroud 402. The
formations or
ribs 435, 436 follow the shape of the pumping vane side faces 445, 446 with
which they
are associated and precede smoothly into the eye portion 430 of the impeller.
[0078] As shown
the formations or ribs 435 and 436 cross in the region of the apex
440 at approximately right angles with respect to one another. Furthermore,
the formations
or ribs 435 and 436 provides for four auxiliary zones 437 each zones being
disposed
between respective adjacent formations or ribs 435 and 436 and adjacent a
respective
passageway 414. This is clearly illustrated in figure 25. The height of the
formations or
ribs 435 and 436 (that is the distance the formations or ribs 435 and 436
project from the
back shroud and nose or eye of the impeller) is generally consistent along the
length of the
formations or ribs 435 and 436. The height of the formations or ribs 435 and
436 may be
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 18 -
about 10% of the distance between the inner faces 403, 404 of the front and
back shroud
401, 402. The width of the formations or ribs 435 and 436 may be about 50% of
the width
of the pumping vane 410, 411, 412 and 413.
[0079] Figures 28
to 32 illustrate an assembly which comprises main liner 120,
front side liner 200, rear side liner 300 and impeller 400 and the way the
various
components work together when in use. The assembly is suitable for use in
pumps such as
for example those described with reference to figures 1 and 2.
[0080] The
operation slurry enters the pumping chamber 124 via the intake section
210 of front side liner 200. The formation 220 tends to direct particulates or
solids towards
a central region of the passageway 212. Because of the orientation of the pump
when in
operation (that is its main axis is generally horizontally disposed) the
solids and
particulates gravitate towards a lower region of passageway 212. The formation
facilitates
a more even spread of the particulates in the flow stream as the slurry enters
the impeller
400 thereby smoothing the flow pattern and reducing wear on both the front
side liner and
the impeller.
[0081]
The raised formations or ribs 435 and 436 when used in conjunction with a
pre-swirl guide vane side liner as shown in figures 16 to 20, the dual benefit
is obtained
that is preconditioning of the slurry flow prior to reaching the impeller is
effected by the
pre-swirl vanes and the "lifting" movement of the new formation serves to move
particulates to a more central location, facilitating more even particle
distribution in the
impeller. The design of the formation is such that a lower angle of
inclination is present on
the inlet side of the front side liner, in order to effect a more gradual
change in the cross-
section and avoid problems of wear associated with rapid changes in cross-
section. This is
in contrast to the discharge side of the front side liner, where a steeper
angle is present.
The steeper angle effects a more pronounced lifting effect by encouraging
particles to
separate from the wall prior to entering the impeller on the eye portion 430
of the impeller
400 further improve the flow pattern tending to keep the solids in the slurry
in the middle
region of the flow stream. The formations of ribs 435 and 436 provide for a
pre-rotation of
the slurry in the region of the impeller eye portion 430 thereby reducing the
relative
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 19 -
velocity on the leading edge of the impeller pumping vanes and further tending
to keep
solids or particulates away from the back shroud this being a major wear rear
in slurry
pumps.
[0082] The slurry
enters the pumping chamber from the impeller with a substantial
turbulent flow pattern. The formation tends to split the flow in the pumping
chamber and
discharge passageways. This leads to a significant reduction in turbulence
effectively
smoothing the flow pattern and increasing wear life. By directing the flow in
this manner,
particles entrained in the flow are less likely to cause the wear which is
typical for slurries
in turbulent flow. The location of the formation is optimised for pumping
applications in
the high flow regime, which typically causes the greatest turbulence and wear
to be near to
the discharge passageway.
[0083]
Finally, the provision of the vanes 330 on the rear side liner 300 inhibits
rotational flow into the seal chamber and thereby stabilizes slurry pressure
in the seal
chamber and reduces wear on the seal. Furthermore, such rotational flow leads
to back
liner wear in cases where expelling vanes are not present on the adjacent
shroud of the
impeller. Incorporation of inhibitor vanes on the back liner can significantly
reduce this
wear problem, which otherwise has been resolved by incorporating impeller back
shroud
expeller or auxiliary vanes.
[0084]
In the foregoing description of preferred embodiments, specific terminology
has been resorted to for the sake of clarity. However, the invention is not
intended to be
limited to the specific terms so selected, and it is to be understood that
each specific term
includes all technical equivalents which operate in a similar manner to
accomplish a
similar technical purpose. Terms such as "top" and "bottom", "front" and
"rear", "inner"
and "outer", "above", "below", "upper" and "lower" and the like are used as
words of
convenience to provide reference points and are not to be construed as
limiting terms.
[0085] The
reference in this specification to any prior publication (or information
derived from it), or to any matter which is known, is not, and should not be
taken as, an
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 20 -
acknowledgement or admission or any form of suggestion that prior publication
(or
information derived from it) or known matter forms part of the common general
knowledge in the field of endeavour to which this specification relates.
[0086] In this specification, the word "comprising" is to be understood in
its
"open" sense, that is, in the sense of "including", and thus not limited to
its "closed" sense,
that is the sense of "consisting only of'. A corresponding meaning is to be
attributed to the
corresponding words "comprise", "comprised" and "comprises" where they appear.
[0087] In addition, the foregoing describes only some embodiments of the
invention(s), and alterations, modifications, additions and/or changes can be
made thereto
without departing from the scope and spirit of the disclosed embodiments, the
embodiments being illustrative and not restrictive.
[0088] Furthermore, invention(s) have been described in connection with
what are
presently considered to be the most practical and preferred embodiments, it is
to be
understood that the invention is not to be limited to the disclosed
embodiments, but on the
contrary, is intended to cover various modifications and equivalent
arrangements included
within the spirit and scope of the invention(s). Also, the various embodiments
described
above may be implemented in conjunction with other embodiments, e.g., aspects
of one
embodiment may be combined with aspects of another embodiment to realize yet
other
embodiments. Further, each independent feature or component of any given
assembly may
constitute an additional embodiment.
[0089] The reference numerals in the following claims do not in any way
limit the
scope of the respective claims.
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
-21 -
Table of Parts
Pump apparatus 100
Pump 10
Pedestal 112
Outer casing 22
Side casing sections 23, 24
Inlet hole 28
Discharge outlet hole 29
Inner liner 11
Main liner 12
Side liners (front and back) 14, 30
Bolts 27
Pumping chamber 42
Seal chamber housing 114
Cover plate 115
Drive shaft 116
Stuffing box 117
Impeller 40
Delivery section 32
Passage 33
Outer end 34
Inner end 35
Sidewall section 15
Inner face 16
Lip 38
Hub 41
Pumping vanes 43
Eye portion 47
Rotation axis X-X
Auxiliary vanes 60
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 22 -
Auxiliary vanes 61
Main liner 120
Main body 122
Pump chamber section 124
Opposed sides 137/138
Major axis Q-Q
Openings 139-140
Pumping chamber 142
Inner surface 144
Peripheral surface portion 145
Side surface portions 146/147
Discharge outlet section 150
Discharge passageway 151
Inner surface 152
Linear axis Y-Y
Discharge outlet port 154
Formation 156
First end 157
Second end 158
Lateral axis Z-Z
Segment 160
Side liner 200
Main body 202
Inner side 204
Outer side 206
Intake section 210
Intake passageway 212
Entry end 214
Exit end 216
Inner surface 218
Guide formation 220
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
-23 -
Leading end portion 222
Trailing end portion 224
Guide surface 226
Segment 227
Chord 228
First group of guides 230
Second group of guides 232
Central axis P-P
Back side liner 300
Main body 302
Annular disc shaped wall 304
Front face 306
Rear face 308
Passageway 310
Inner surface 311
Outer peripheral edge 312
Bosses 317
Recess 316
Primary axis P-P
Recess inner surface 318
Peripheral wall 320
Crests 322
Valleys 324
Vanes 330
Upper surface 331
Vanes first group 332
Vanes second group 334
Pump impeller 400
Front shroud 401
Back shroud 402
Inner face 403/404
CA 03043338 2019-05-09
WO 2018/000032 PCT/AU2017/050658
- 24 -
Outer face 405/406
Main/rotation axis B-B
Pumping vanes 410/411/412/413
Hub 415
Leading edge 420/421/422/423
Trailing edge 424/425/426/427
Eye portion 430
Raised formations 435/436
Pressure side face 445
Rear side face 446
Auxiliary passageway 447
Inlet opening 450
Interior region 455
Apex 440
