Grooved side bushing for centrifugal pump

Abstract

A side liner for a centrifugal pump is disclosed. The side liner includes an aperture for access to a central chamber of the centrifugal pump through the side liner. The side liner also includes a plurality of grooves on a surface that contacts material pumped by the centrifugal pump, the plurality of grooves extending radially from an inner edge of the surface near the aperture to an outer edge.

Description

Technical Field

[0001] This invention relates generally to the field of centrifugal pumps. More specifically, this invention relates to a side bushing for a centrifugal pump. Background Technology

[0002] One type of centrifugal slurry pump typically includes an outer pump casing enclosed by bushings. The bushing has a pumping chamber therein, which can be a volute, semi-volute, or concentric configuration, and is arranged to house an impeller mounted to rotate within the pumping chamber. A drive shaft is operatively connected to the pump impeller to rotate it, and the drive shaft enters the pump casing from one side. The pump also includes a pump inlet, which is typically coaxial with respect to the drive shaft and located on the side of the pump casing opposite the drive shaft. A discharge outlet is also present, typically located at the periphery of the pump casing. The bushing includes a main bushing (sometimes called a volute) and front and rear bushings, which are enclosed within the outer pump casing. The front bushing is often referred to as a front bushing suction plate or throat sleeve. The rear bushing is often referred to as a frame plate bushing insert.

[0003] An impeller typically includes a hub and at least one shroud, with a drive shaft operatively connected to the hub. Pumping blades are disposed on one side of the shroud, with a discharge passage between adjacent pumping blades. The impeller can be enclosed, with two shrouds provided, and the pumping blades disposed between them. The shrouds are commonly referred to as the front shroud and rear shroud adjacent to the pump inlet. The impeller can also be an open-face type comprising only one shroud.

[0004] One of the main wear areas in a slurry pump is the front and rear side bushings. Slurry enters the impeller from the center or eyelet, is then thrown to the periphery of the impeller, and enters the pump casing. Because of the pressure difference between the casing and the eyelet, the slurry tends to try to migrate into the gap between the side bushings and the impeller, resulting in high wear on the side bushings.

[0005] When a slurry pump operates, the impeller's rotational motion provides energy to the slurry. The slurry flows centrifugally and is collected by the main bushing, which directs the slurry towards the discharge outlet. Due to the shape of the main bushing, the water distribution area affects the flow pattern of the recirculated slurry. The side bushings come into contact with the slurry within the impeller shroud cavity. The proximity of the main bushing water distribution angle of the typical impeller outer shroud or impeller blades and frame plate bushing in a centrifugal slurry pump can affect the erosion rate experienced by the side bushings. In mill circuits that typically operate at low flow rates, the erosion rate of the side bushings increases due to the increased internal recirculation rate, leading to the side bushings eventually becoming short-life components due to localized wear (sometimes referred to as "gowing").

[0006] To minimize wear in the gap area, slurry pumps employ auxiliary blades or discharge blades on the front shroud of the impeller. These blades can also be located on the rear shroud. The discharge blades cause the slurry to rotate within the gap, creating a centrifugal field that reduces the backflow driving pressure, lowers the flow velocity, and thus reduces wear on the side bushings. The purpose of these auxiliary blades is to reduce recirculation of the flow through the gap. These blades also reduce the inflow of relatively large solid particles into the gap.

[0007] References to any existing publications (or information derived from existing publications) or any known matters in this specification are not, and should not be construed as, an admission or acceptance or, in any way, an implication that existing publications (or information derived from existing publications) or known matters constitute part of the general knowledge in the field covered by this specification. Summary of the Invention

[0008] This summary is provided to introduce some concepts in a simplified form, which will be further described in the detailed description below. This summary is not intended to identify essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter.

[0009] In a first embodiment, a side bushing for a centrifugal pump is provided by way of example, the side bushing comprising: an orifice for access to the central chamber of the centrifugal pump through the side bushing; and at least four grooves on a surface in contact with material pumped by the centrifugal pump, the at least four grooves extending radially from an inner edge of the surface near the orifice to an outer edge.

[0010] In one embodiment, each of the at least four grooves is an arc having curvature in a direction opposite to the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0011] In one embodiment, each of the at least four grooves is an arc having curvature in the same direction as the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0012] In one embodiment, each of the at least four grooves is a radially extending straight line.

[0013] In one embodiment, each of the at least four grooves is a radial straight line angled in a direction opposite to the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0014] In one embodiment, each of the at least four grooves is a radial straight line angled in the same direction as the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0015] In one embodiment, the curvature of the arc lies in a plane parallel to the surface.

[0016] In one embodiment, the depth of each of the at least four grooves varies on the surface.

[0017] In one embodiment, the depth of each of the at least four grooves decreases toward the outer edge.

[0018] In one embodiment, the depth of each of the at least four grooves decreases toward the inner edge.

[0019] In one embodiment, the curvature of each of the at least four grooves is substantially similar to the curvature of the main pumping blades of the impeller.

[0020] In one embodiment, the depth of each of the at least four grooves is deepest in the middle region located between the outer edge and the inner edge of the surface.

[0021] In one embodiment, the width of each of the at least four grooves is larger in the middle region located between the outer edge and the inner edge of the surface.

[0022] In one embodiment, each of the at least four grooves has a matching shape.

[0023] In one embodiment, the at least four grooves are recessed grooves.

[0024] In one embodiment, the at least four grooves are protruding grooves.

[0025] In one embodiment, the at least four grooves include recessed grooves and protruding grooves.

[0026] In one embodiment, the side bushing is a front side bushing.

[0027] In one embodiment, the orifice provides an inlet for the slurry to enter the central chamber of the centrifugal pump.

[0028] In one embodiment, the side bushing is a rear side bushing.

[0029] In one embodiment, the orifice provides an inlet for the impeller shaft.

[0030] In one embodiment, the side bushing has fewer than 100 grooves.

[0031] In one embodiment, each of the at least four grooves has a depth of at least 10 mm.

[0032] In one embodiment, a centrifugal pump is provided by way of example, the centrifugal pump comprising: a side bushing, the side bushing including: an orifice for access to a central chamber of the centrifugal pump through the side bushing; and at least four grooves on a surface in contact with material pumped by the centrifugal pump, the at least four grooves extending radially from an inner edge of the surface near the orifice to an outer edge.

[0033] In one embodiment, the centrifugal pump includes: a second side bushing, the second side bushing including: an orifice for access to the central chamber of the centrifugal pump through the second side bushing; and at least four grooves on a surface in contact with material pumped by the centrifugal pump, the at least four grooves extending radially from an inner edge of the surface near the orifice of the second bushing to an outer edge.

[0034] In one embodiment, the side bushing is a rear side bushing, and the second side bushing is a front side bushing.

[0035] In one embodiment, each of the at least four grooves of the side bushing is an arc having curvature in a direction opposite to the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0036] In one embodiment, each of the at least four grooves of the side bushing is an arc having curvature in the same direction as the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0037] In one embodiment, each of the at least four grooves of the side bushing is a radially extending straight line.

[0038] In one embodiment, each of the at least four grooves of the side bushing is a radial straight line angled in a direction opposite to the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0039] In one embodiment, each of the at least four grooves of the side bushing is a radial straight line angled in the same direction as the curvature direction of the main pumping blades of the centrifugal pump impeller.

[0040] In one embodiment, the curvature of the arc lies in a plane parallel to the surface.

[0041] In one embodiment, the depth of each of the at least four grooves of the side bushing varies on the surface.

[0042] In one embodiment, the depth of each of the at least four grooves is deepest in the middle region between the outer edge and the inner edge of the surface of the side bushing.

[0043] In one embodiment, the at least four grooves of the side bushing are recessed grooves.

[0044] In one embodiment, the side bushing has fewer than 100 grooves.

[0045] In one embodiment, each of the at least four grooves has a depth of at least 10 mm. Attached Figure Description

[0046] Exemplary embodiments are provided in the following description of at least one preferred but non-limiting embodiment, given only by way of example and in conjunction with the accompanying drawings.

[0047] Figure 1 This is a schematic partial cross-sectional side view of a pump device according to one embodiment;

[0048] Figure 2 yes Figure 1 A more detailed schematic partial cross-sectional side view of a part of the pump unit;

[0049] Figure 3 This is a view of the impeller based on one implementation scheme;

[0050] Figure 4 yes Figure 3 An alternative view of the impeller;

[0051] Figure 5A and Figure 5B These are alternative auxiliary blades for an impeller according to one implementation scheme;

[0052] Figure 6A A side bushing with a curved groove is shown according to one embodiment;

[0053] Figure 6B A side bushing with a straight radial groove is shown according to one embodiment;

[0054] Figure 6C A side bushing with straight, angled radial grooves is shown according to one embodiment;

[0055] Figure 7 A rear bushing with a curved groove is shown according to one embodiment; and

[0056] Figure 8 It shows Figure 6A The cross-section of the side bushing;

[0057] Figures 9A to 9F The depth profile of the groove in the side bushing according to one embodiment is shown;

[0058] Figures 10A to 10E A cross-section of the groove in the side bushing according to one embodiment is shown;

[0059] Figures 11A to 11D The slurry velocity on the pump bushing according to at least one embodiment is shown; and

[0060] Figure 12 A groove in the side bushing according to one embodiment is shown. Detailed Implementation Plan

[0061] The following patterns are described only as examples to provide a more precise understanding of the subject matter of one or more preferred embodiments.

[0062] Exemplary side bushing for a centrifugal pump

[0063] A side bushing for a centrifugal pump is described. When installed in a centrifugal pump, the side bushing can contact a material such as slurry pumped by the centrifugal pump. The side bushing has an orifice for access to the central chamber of the centrifugal pump through the side bushing. Located on the surface are multiple grooves that extend radially from an inner edge of the surface near the orifice to an outer edge. The side bushing can also be installed as part of the centrifugal pump.

[0064] Side bushings can be referred to as patterned side bushings for centrifugal pumps. A patterned side bushing has multiple grooves on its surface that comes into contact with the material pumped by the centrifugal pump. The grooves on the side bushing surface can extend radially from near the inner edge of the surface, located near the side bushing orifice, to the outer edge of the surface. The grooves of the side bushing can have an arc shape with curvature in the opposite direction to the curvature direction of the main or auxiliary blades on the centrifugal pump impeller.

[0065] Please refer to the attached diagram for details. Figure 1 The diagram generally illustrates a pump assembly 200, which includes a pump 10 and a pump housing support, which is in the form of a base or pedestal 112 on which the pump 10 is mounted. The base is also referred to as a frame in the pump industry. The pump 10 generally comprises an outer casing formed by two side casing portions or sections 23, 24 (sometimes also referred to as frame plates and cover plates) joined together around the periphery of two side casing sections 23, 24. The pump 10 has side openings, one of which is an inlet port 28, and another is a discharge outlet port 29. When used in processing equipment, the pump is connected to the inlet port 28 and the outlet port 29 via piping, for example, to facilitate pumping mineral slurries.

[0066] Pump 10 also includes an inner pump bushing 11 disposed within the housing and comprising a main bushing 12 and two side bushings 14, 30. The side bushing 14 is located near the rear end of pump 10 (i.e., closest to the base or seat 112), while the other side bushing (or front bushing) 30 is located near the front end of the pump and inlet port 28. Side bushing 14 is also referred to as the rear portion or frame plate bushing insert, and side bushing 30 is also referred to as the front portion or throat. The main bushing includes two side openings. Figure 2 As shown, the rear bushing 14 includes a disc-shaped body 100 having an inner edge 17 and an outer edge 13. The body 100 has a first side 15 and a second side 18 having a side surface 16.

[0067] like Figure 1 As shown, when the pump is assembled and in use, the two side shell parts 23, 24 of the housing are connected together by bolts 27 located around the periphery of the shell parts 23, 24. In some embodiments, the main bushing 12 may also comprise two separate parts assembled within each of the side shell parts 23, 24 and brought together to form a single main bushing, but... Figure 1 In the example shown, the main bushing 12 is made as a single piece, shaped like a car tire. The bushing 11 can be made of materials such as rubber, elastomer, or metal.

[0068] When assembling the pump, the side opening in the main bushing 12 is filled or accommodated by two side bushings 14, 30 to form a continuous bushing pumping chamber 42 disposed within the pump housing. A sealing chamber shell 114 encloses the side bushings (or rear portion) 14 and is arranged to seal the space or chamber 118 between the drive shaft 116 and the base or seat 112 to prevent leakage from the rear region of the housing. The sealing chamber shell takes the form of a circular disc segment and an annular segment with a central hole, and is known in one arrangement as a stuffing box 117. The stuffing box 117 is arranged adjacent to the side bushings 14 and extends between the base 112 and the shaft sleeve and the packing surrounding the drive shaft 116.

[0069] like Figure 1 and Figure 2 As shown, impeller 40 is positioned within main bushing 12 and is mounted or operatively connected to drive shaft 116, which is adapted to rotate about axis of rotation XX. A motor drive (not shown) is typically attached by pulleys to the exposed end of shaft 116, located in an area behind base or pedestal 112. Rotation of impeller 40 causes the pumped fluid (or solid-liquid mixture) to flow from a conduit connected to an inlet port through pump chamber 42, located within main bushing 12 and side bushings 14, 30, and then out of the pump through a discharge outlet port.

[0070] The impeller 40 includes a hub 41 from which a plurality of circumferentially spaced pumping blades 43 extend. An eye portion 47 extends forward from the hub 41 toward a channel 33 in the front bushing 30. The impeller 40 also includes a front shroud 50 and a rear shroud 51, as well as an impeller inlet 48, with the blades 43 disposed between and extending therebetween the front and rear shrouds. The hub 41 extends through an aperture formed by the inner edge 17 of the rear bushing 14.

[0071] The impeller front shroud 50 includes an inner surface 55, an outer surface 54, and a peripheral edge portion 56. The rear shroud 51 includes an inner surface 53, an outer surface 52, and a peripheral edge portion 57. The front shroud 50 includes an inlet 48 serving as an impeller inlet, and blades 43 extend between the inner surfaces of the shrouds 50 and 51. When viewed from the front (i.e., along the axis of rotation XX), the shrouds are generally circular or disc-shaped.

[0072] Each impeller shroud may have multiple auxiliary blades or discharge blades on its outer surface 52, 54. Auxiliary blades are optional features of the impeller, which will be positioned below relative to... Figure 3 and Figure 4 To provide a more detailed description.

[0073] The front bushing 30 has a cylindrical inlet section 32 extending from the outermost end 34 to the innermost end 35. When the pump 10 is operating, the outermost end 34 can be connected to a feed pipe (not shown), through which slurry is fed to the pump 10. The innermost end 35 has a raised lip 38, which, when in the assembled position, is arranged to be in close contact with the impeller 40. The front bushing 30 has a surface 37 facing the pump chamber 42 and an outer edge 26 that contacts the pump 10 during pump operation.

[0074] Now refer to Figure 3 and Figure 4 The description can be used for an exemplary impeller of pump 10. Figure 3 The impeller 300 is shown as a view from the pump inlet side, with the front shroud 320 also shown. Figure 4 The impeller 300 is shown as a view from the drive shaft inlet side, with the rear shroud 325 also shown. That is, Figure 3 and Figure 4 Impeller 300 is shown from opposite sides.

[0075] The pump inlet is coaxial with respect to the drive shaft and located on the side of the pump casing opposite to the drive shaft. The drive shaft is attached to the impeller 300 via a hub 305. The impeller 300 has circumferentially spaced pumping blades 310 with leading edges 315. The circumferentially spaced pumping blades 310 draw slurry from the pumping chamber of the centrifugal pump and pump the slurry out of the pumping chamber. Elongated, flat-topped protrusions 330 are located between the circumferentially spaced pumping blades 310. The protrusions 330 have an outer end 335 adjacent to the outer peripheral edge of the rear shroud 325 and an inner end 340 located approximately in the middle of the channel formed by the circumferentially spaced pumping blades 310.

[0076] Auxiliary blades are located on each face of the impeller 300. Auxiliary blades 345 and 350 are located on the rear surface of the impeller 300, i.e., the surface closest to the rear bushing of the pump. Auxiliary blade 355 is located on the front surface of the impeller 300, i.e., the surface closest to the front bushing of the pump. When viewed from the direction of rotation of the impeller 300, the circumferentially spaced pumping blades 310 are generally referred to as backward-curved blades. Auxiliary blades, such as auxiliary blades 345, 350, and 355, are also curved to varying degrees and are shown as having a curvature in the same direction as the circumferentially spaced pumping blades 310. Similar to the circumferentially spaced pumping blades 310, the auxiliary blades can be considered backward-curved.

[0077] Figure 5A and Figure 5B An alternative design for auxiliary blades on the rear surface of the impeller is shown. Impeller 500 has a plurality of evenly spaced blades 510. Impeller 520 also has a plurality of evenly spaced blades 530. However, the blades 530 extend to an annular protrusion 540 located at the edge of the surface of impeller 520. The annular protrusion 540 has a channel 550 to allow slurry in the pump to flow through the annular protrusion 540. When viewed from the direction of rotation of impeller 500 or impeller 520, both blades 510 and blades 530 are rearwardly curved blades.

[0078] Although the auxiliary blades of impellers 300, 500, and 520 have different designs, they all contribute to the pumping of slurry in a centrifugal pump. The auxiliary blades can work in conjunction with other blades, such as the circumferentially spaced pumping blades 310 of impeller 300, to move slurry from the inlet to the outlet of the centrifugal pump. However, as the slurry moves within the centrifugal pump, it can cause wear on the front bushing, side bushings, and main bushing. Alternatively, the centrifugal pump can use impellers without auxiliary blades, relying solely on the main blades to move the slurry within the pump.

[0079] Now relative to Figure 6ADescribing a side bushing, this figure illustrates a patterned side bushing 600, more specifically, a rear side bushing with a radial vortex pattern for use in centrifugal pumps such as pump 10. As described above, the radial vortex pattern on side bushing 600 can reduce localized wear on the side bushing compared to a side bushing with a flat surface. Reduced wear can increase the service life of the patterned side bushing. Typically, side bushings such as side bushing 600 are replaceable parts in centrifugal pumps made of suitable materials such as rubber, elastomers, or metals. Side bushing 600 is in a similar manner to... Figure 1 The side bushing 14 is operated in the manner described.

[0080] The side bushing 600 has a centrally located orifice 610. The orifice 610 allows a shaft to enter the pumping chamber of the centrifugal pump to rotate an impeller (such as impeller 40 or impeller 300 as described above). The side bushing 600 has a surface 615 facing the pumping chamber and in contact with the slurry pumped by the centrifugal pump. The surface 615 has an inner edge 620 that forms the edge of the orifice 610 and seals against a drive shaft (such as drive shaft 116 as described above). The outer edge 630 of the surface 615 can form a seal with a main bushing (such as main bushing 12 as described above).

[0081] Multiple grooves 640 are located on surface 615. The grooves 640 are formed in surface 615 and can extend radially from inner edge 620 to outer edge 630, such as... Figure 6A As shown. The groove 640 can be considered to be in a plane parallel to surface 615. The groove 640 may have what will be shown below relative to... Figures 10A to 10E A more detailed description of the cross-section. The depth of the groove 640 can vary above the surface 615. One example of the depth profile of the groove 640 is that the groove 640 is shallower closer to the inner edge 620 and the outer edge 630. Using this depth profile, the deepest part of the groove 640 can be located at or near the intermediate region 650 between the inner edge 620 and the outer edge 630. The depth profile of the groove 640 can vary in different ways, which will be discussed below relative to... Figures 9A to 9D To explain.

[0082] Figure 6A The groove 640 is not a straight line, but an arc or a curve. The direction of curvature of the arc can play a role in reducing the planing of the side bushing 600. The groove 640 is formed as an arc with curvature in the opposite direction to that of the main pumping blades of the centrifugal pump impeller. If auxiliary blades are fitted, the curvature of the groove 640 is also opposite to that of the auxiliary blades of the impeller. Therefore, when observing the slotted surface of the bushing, the direction of curvature between the front and rear bushings will be different. Compared to the backward-curving blades of the impeller, the front and rear bushings have grooves that can be described as forward-curving when viewed from the direction of impeller rotation.

[0083] Now relative to Figure 6B Describing a side bushing, the figure shows a radially grooved side bushing 690 with a groove 660 extending radially in a straight line from the inner edge 620 to the outer edge 630. The radially grooved side bushing 690 is similar to the one described above relative to the one with an alternative groove pattern, except that it has an alternative groove pattern. Figure 6A The side bushing 600 is described. Like the side bushing 600, the radially grooved side bushing 690 can be used in centrifugal pumps such as pump 10. Compared to a flat-surfaced side bushing, the pattern on the radially grooved side bushing 690 can reduce localized wear on the side bushing. Reduced wear can increase the service life of the patterned side bushing. Typically, side bushings such as the radially grooved side bushing 690 are replaceable parts in centrifugal pumps made of suitable materials such as rubber, elastomers, or metals. The radially grooved side bushing 690 is similar in design to... Figure 1 The side bushings 14 and 600 are operated in the manner described.

[0084] Now relative to Figure 6C Describing a side bushing, the figure shows an angled radial grooved side bushing 695 with a groove 670 extending radially but at an angle or obliquely from an inner edge 620 to an outer edge 630. That is, the angled radial grooved side bushing 695 has angled or oblique radial grooves compared to the pure radial groove 660 of the radial grooved side bushing 690. The angled radial grooved side bushing 695 is similar to the side bushing 600 or radial grooved side bushing 690 described above, except that it has an alternative groove pattern. Like the side bushing 600 and radial grooved side bushing 690, the angled radial grooved side bushing 695 can be used in centrifugal pumps such as pump 10. Compared to a flat-surfaced side bushing, the pattern on the angled radial grooved side bushing 695 can reduce localized wear on the side bushing. Reduced wear can increase the service life of the patterned side bushing. Typically, side bushings such as angled radial grooved side bushings 695 are replaceable parts in centrifugal pumps, made of suitable materials such as rubber, elastomers, or metals. Angled radial grooved side bushings 695 are similar to... Figure 1 It operates in the manner of side bushing 14, side bushing 600 and radial groove side bushing 690.

[0085] Figure 6C The angled radial grooved side bushing 695 shown has a groove 670 that is angled in the same direction as the curvature of the groove 640 of the side bushing 600. That is, the groove 670 is angled in a direction opposite to the curvature direction of the main pumping blades of the centrifugal pump impeller. In an alternative embodiment, the groove 670 may be angled in the same direction as the curvature of the main pumping blades of the impeller.

[0086] relative to Figure 7 The diagram describes a front bushing characterized by a radial vortex pattern of curved grooves. The figure illustrates a front bushing 750 that can be used in a centrifugal pump such as pump 10. The front bushing 750 has an orifice 755 that allows slurry to enter the pumping chamber of the centrifugal pump. A surface 780 extends from an inner edge 760 to an outer edge 765. When the front bushing 750 is installed in an operating centrifugal pump, the surface 780 can contact the slurry in the pumping chamber. The surface 780 has a plurality of recessed radial grooves 770, which are arc-shaped and extend from the inner edge 760 to the outer edge 765. The curvature of the arcs is in the opposite direction to the curvature of the blades or auxiliary blades of the centrifugal pump impeller. When the front bushing 750 is on the opposite side of the impeller, the curvature direction of the grooves 770 is in the opposite direction to the curvature of the impeller blades or auxiliary blades of the centrifugal pump. Figure 6A The grooves 640 of the side bushing 600 are in the opposite direction. The depth of the plurality of grooves 770 can vary on the surface 780, with the deepest portion of the grooves 770 located at the intermediate region 775. In an alternative embodiment, the grooves 770 can be curved in the same direction as the curvature of the impeller blades. Alternatively, the front bushing 750 can have other groove patterns, such as a straight radial groove pattern of the radial groove side bushing 690, an angled radial groove pattern of the angled radial groove side bushing 695, or an angled radial groove pattern that is angled in the same direction as the curvature of the impeller's main pumping blades.

[0087] Now relative to Figure 8 The side bushing 800 is described in cross-section. The side bushing 800 has an orifice 810 and an inner edge 820 and an outer edge 830 of a surface 835. Grooves are recessed into the surface 835. Due to the curved shape of the grooves, the cross-section of the side bushing 800 shows more than one groove, which intersects the cross-section at different angles. Since the grooves on the surface 835 are shallowest near the inner edge 820 and the outer edge 830, the inner edge groove 840 appears to have a shallow cross-section. As can be seen from grooves 850, 860, 870, and 880, the depth of the grooves increases towards the midpoint of the surface 835. Figure 8 The shape of the groove varies with the angle at which the groove intersects the cross-section. Therefore, groove 850 is shown as having a wider cross-section than groove 880. However, all grooves on surface 835 can be formed with the same or matching cross-sections.

[0088] Now relative to Figures 9A to 9FDescribes the depth profile of the grooves in the side bushing. Depth profiles can be used for bushings such as side bushings 14 and 30, side bushing 600, radially grooved side bushing 690, angled radially grooved side bushing 695, and front side bushing 750. The depth profile is the depth of the groove traveling along the groove from the inner edge of the bushing to the outer edge of the bushing surface. Typically, deeper grooves will persist for a longer period as the bushing is worn down by the slurry.

[0089] Each element in the profile is shown on a graph having a distance from the central axis 910 in the x-direction and a depth axis 920 in the y-direction. Marked at a distance from the central axis 910 are the inner edge 930 from the center of the surface, the midpoint 940 of the surface, and the outer edge 950 of the surface. The depth of the groove is shown from the inner edge 930 to the outer edge 950.

[0090] The depth profile of the groove can vary in different ways, and Figures 9A to 9F The profiles shown are six instances, with each of the depth profiles being deepest near the midpoint of the bushing's surface. Figure 9A A V-shaped profile 900 is shown, where the depth of the groove varies linearly from a shallow point near the inner edge 930 and the outer edge 950 to a deepest point near the midpoint 940. Figure 9B An alternative profile is shown, in which a flat-bottomed V-shaped profile 901 with the deepest part of the depth profile appears above the extended area of ​​the surface. This shape can be changed by altering the extent of the flat portion of the profile or the rate of change of the profile at each end.

[0091] Figure 9C A continuously curved U-shaped profile 902 is shown, wherein the deepest part of the groove appears near the midpoint 940, and the groove is shallowest near the inner edge 930 and the outer edge 950. Various aspects of the curve can be modified and changed, such as the "flatness" of the bottom of the curved U-shaped profile 902, the initial slope near the inner edge 930 and the outer edge 950, or the rate of change of the curved U-shaped profile 902. Figure 9D A flat-bottomed U-shaped profile 903 is shown, which can be considered to have a flat bottom similar to a flat-bottomed V-shaped profile 901, but with curved side profiles similar to a curved U-shaped profile 902. Like the flat-bottomed V-shaped profile 901 and the curved U-shaped profile 902, aspects of the flat-bottomed U-shaped profile 903 can vary, such as the size of the flat portion or the initial slope of the depth profile near the inner edge 930 and the outer edge 950.

[0092] Alternative depth profiles can make the groove depth decrease only towards the inner edge of the bushing surface or only towards the outer edge of the bushing surface. This profile can be called a J-shaped profile. Examples of this profile are found in... Figure 9EThe diagram shows a curved asymmetrical profile 904, where the deepest part of the groove is located between the midpoint 940 and the outer edge 950. Although the curved asymmetrical profile 904 has a curved profile, other profiles are also possible. Figure 9F A straight asymmetric profile 905 is shown, in which the deepest portion of the groove is located between the midpoint 940 and the outer edge 950. While both the curved asymmetric profile 904 and the straight asymmetric profile 905 have the deepest portion of the groove positioned toward the outer edge 950, in an alternative, the deepest portion of the groove may be positioned closer to the inner edge 930.

[0093] The groove depth can have an average of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 35, 40, 45, or 50 mm. The maximum groove depth can be any of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 35, 40, 45, or 50 mm. The groove depth can have an average depth of at least 10 mm, at least 20 mm, at least 30 mm, at least 40 mm, or at least 50 mm. Due to the abrasive nature of the slurry, the groove depth should be deep enough so that the groove does not wear out too quickly. The average groove depth can also be expressed as a percentage of the bushing thickness, such as 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, or 20%. Alternatively, the average groove depth as a percentage of the bushing thickness can be expressed as a range, such as 11% to 16%, 10% to 17%, or 10% to 20%. The groove width can be an average of at least 10 mm, at least 20 mm, at least 30 mm, at least 40 mm, or at least 50 mm.

[0094] Now relative to Figures 10A to 10E Describes an exemplary groove cross-section. The groove cross-section represents the shape of a groove cut or cast into the surface of the bushing, and is perpendicular to the top relative to... Figures 9A to 9D The grooves are seen in the cross-section of the depth profile discussed. The grooves can be formed in the bushing as part of a mold used to manufacture the bushing, or they can be cut into the surface of the bushing after it has been cast. Typically, the grooves on the side bushings have the same or matching cross-sections.

[0095] Figure 10AA semi-circular profile 1000 is shown. The radius of the semi-circular profile 1000 can be 5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 mm. The radius of the semi-circular profile 1000 can also be expressed as a percentage of the bushing thickness, such as 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, or 20%. The percentage of the radius of the semi-circular profile 1000 to the bushing thickness can be expressed as a range, such as 11% to 16%, 10% to 17%, or 10% to 20%. In one example, the radius of the semi-circular profile 1000 is constant, while the depth of the groove is varied. Alternatively, the radius of the semi-circular profile 1000 can vary above the length of the groove, with the values ​​listed above used for the deepest part of the groove. Figure 10B A narrow semi-elliptical profile 1010 is shown, with a depth greater than its width. This profile can be used when the depth of a groove is greater than its width. The opposite of the narrow semi-elliptical profile 1010 is a wide semi-elliptical profile 1020, as shown... Figure 10C As shown. This profile is useful when a relatively shallow groove is required.

[0096] You can also use a contour with straight edges. An example is... Figure 10D V-shaped profile 1030 or Figure 10E The flat-bottomed V-shaped profile 1040 has the advantage over curved groove cross-sections because the angle between the bushing surface and the groove is constant until the groove wears down. For curved profiles, the angle between the surface and the groove changes as the bushing surface wears down.

[0097] The angle between the groove and the bushing surface can be important for ensuring proper operation of patterned side bushings. During operation, the groove in the side bushing can cause turbulence in the slurry over a region of the side bushing surface. Turbulence can prevent planing of the side bushing by slowing down the slurry and dissipating energy from the slurry flow. Therefore, a very shallow angle between the groove and the side bushing may not generate sufficient turbulence, and planing of the side bushing may occur, although at a lower rate compared to a flat-surface bushing.

[0098] Variations of the groove cross-section described above can also be used. Examples include combinations of flat bottoms and semicircles, narrow semi-ovals, or wide semi-ovals. Grooves can also be positioned adjacent to each other, so that two grooves form a larger groove. One example is two V-shaped profiles forming a W-shaped profile.

[0099] The width of the groove in the side bushing can vary on the surface of the side bushing. For those with the above... Figures 10A to 10DThe groove width of any of the contours discussed can vary with the depth of the groove. For example, the V-shaped contour 1030 will be narrower in the shallow section of the groove and wider in the deeper section. A similar variation in groove width may also occur for the semi-circular contour 1000, the narrow semi-elliptical contour 1010, the wide semi-elliptical contour 1020, and the flat-bottomed V-shaped contour 1040. In some embodiments, the cross-section of the groove can be varied to change the groove width while maintaining a constant depth. This can be achieved, for example, by changing the angle of the V in the V-shaped contour 1030.

[0100] Although relative to Figures 6A to 6C and Figure 7 The described grooves are shown as arcuate or curved grooves, but alternative shapes can be used. In one embodiment, the groove may be straight and extend radially from the center orifice to the edge of the bushing. Alternatively, the groove may be straight but at an angle to the radial line. Typically, the groove will be angled in the direction opposite to the direction of rotation of the impeller's main or auxiliary blades. That is, the groove is angled forward when viewed from the direction of rotation of the impeller. Alternatively, if auxiliary blades are fitted, the straight groove may be angled in the same direction as the main or auxiliary blades. That is, the groove is angled backward when viewed from the direction of rotation of the impeller. In one alternative, the grooves of the front and rear bushings have matching patterns. Alternatively, the groove patterns may be different. For example, the front bushing may have curved grooves in the direction opposite to the main blades on the impeller, while the rear bushing may have curved grooves in the same direction as the blades on the impeller.

[0101] Another alternative is to arrange each of the grooves into multiple straight line segments to approximate a curve. In one example, only two straight line segments can be used for the groove, with an angle between the two segments. The angle between the two segments can be set to approximate a backward-curving groove or a forward-curving groove. More than two straight line segments can also be used. When the curve is approximated by straight line segments, these segments can be connected or disconnected. However, the gap between each straight line segment may increase the planing of the bushing surface because there are no grooves to disrupt the flow of the slurry. Grooves with approximate curves composed of straight lines can be curved in the opposite direction to the main or auxiliary blades of the impeller, or in the same direction as the main or auxiliary blades of the impeller. That is, when viewed from the direction of rotation of the impeller, the groove can be backward-curved or forward-curved.

[0102] The shape or curvature of the groove's arc can also vary. In one embodiment, the curvature can be similar to or substantially similar to the curvature of the impeller's main blades. Alternatively, the groove's curvature can match the curvature of auxiliary blades on the impeller. Another alternative to the groove's curvature could be a curvature independent of any of the blades on the impeller. Instead, the curvature can be chosen based on the impeller's expected speed. For example, a slower impeller speed might have a groove with a smaller curvature compared to a faster impeller speed, and vice versa.

[0103] Now relative to Figures 11A to 11D The description illustrates simulation results showing the velocity of materials such as slurry flowing through the pump bushing. Each of the figures shows a pump bushing with a rear bushing and a portion of a main bushing with a different rear bushing design. The impeller of the pump used in the simulation is not equipped with auxiliary blades.

[0104] Figure 11A A pump bushing 1100 with a flat rear side bushing is shown. The pump bushing has a main bushing and a high-speed zone 1105 near the main bushing dividing angle. The high-speed zone extends from the main bushing to the surface of the side bushings. A medium-speed zone 1115 of the side bushings covers most of the side bushings, and a high-speed zone 1110 of the main bushings is shown, in which the slurry moves around the main bushing toward the outlet 1120.

[0105] Figure 11B A pump bushing 1125 with a rearwardly curved rear bushing is shown. The grooves on the rear bushing curve in the same direction as the blades on the impeller. A mixing velocity zone 1130 of the side bushing is located near the water separation angle of the main bushing, and both high-speed and low-speed slurry zones are shown. The surface of the side bushing has numerous high-speed slurry contact zones, such as the side bushing high-speed zone 1135. The pump bushing also has a main bushing high-speed zone 1140 leading to an outlet 1145. Due to the curvature of the grooves on the rear bushing, the grooves have a groove angle 1147, which is the angle between the beginning and end of the groove when measured from the center of the bushing. The groove angle 1147 is marked from one end of the groove at its inner edge to the other end at its outer edge. For each of the 50 grooves, the grooves of the pump bushing 1125 have the same groove angle of approximately 40 degrees.

[0106] Figure 11CA pump bushing 1150 with a forward-curved rear bushing is shown. The grooves on the rear bushing are curved in the opposite direction to the blades on the impeller. The main bushing high-speed zone 1155 is located near the water-dividing angle of the main bushing; however, the side bushing mixing speed zone 1160 has low-speed and medium-speed zones that show the effect of the grooves on the slurry velocity on the side bushing surface. The slurry velocity above the slotted surface of the side bushing is lower than in the adjacent zone of the main bushing. Like pump bushings 1100 and 1125, there is a main bushing high-speed zone 1165 leading to the outlet 1170. Because the grooves on the rear bushing are curved, the grooves have a groove angle 1172 similar to the groove angle 1147. For each of the 50 grooves, the grooves of pump bushing 1150 have the same groove angle of approximately 40 degrees. In one example, the groove angle 1172 can be a negative angle, opposite to the positive groove angle 1147. A front bushing with grooves can also have a groove angle.

[0107] Figure 11D A pump bushing 1175 with a straight radial rear bushing is shown. The grooves on the rear bushing are straight and extend radially in a straight line from near the orifice 1178. The high-speed zone 1180 of the main bushing is located near the water-cutting angle of the main bushing; however, the slurry velocity on the surface of the bushing is generally low, and the highest velocity on the surface of the side bushing is the medium-speed zone 1185 of the side bushing, located near the high-speed zone 1180 of the main bushing. As with other main bushings, there is a high-speed zone 1190 of the main bushing leading to the outlet 1195. The pump bushing 1175 has a zero-degree groove angle because the grooves begin and end at the same angle from the center of the pump bushing 1175.

[0108] The aforementioned groove has a groove angle of approximately 40 degrees. Other angles are also possible, such as 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, and 180 degrees. The groove can also be in the range of 10-45, 10-90, 20-45, 20-90, 30-45, 30-90, 40-45, 40-90, 50-90, 60-90, and 70-90 degrees. The number of grooves on the bushing can be 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, or 150. Alternatively, the number of grooves can be expressed as a range, such as 10-50, 10-80, 20-50, 20-80, 30-50, 30-80, 40-50, 40-80, 50-80, 60-80, or 70-80. Alternatively, the number of grooves can be expressed as more than four, more than eight, more than 16, or more than 32. The number of grooves can also be less than 100, less than 90, less than 80, less than 70, less than 60, or less than 50. The groove can also be any combination of the listed ranges, such as greater than 4 and less than 100, greater than 8 and less than 100, or greater than 8 and less than 90.

[0109] Figure 12A side bushing 1210 with a groove 1220 is shown. The groove 1220 extends from an inner edge 1270 to an outer edge 1280. The groove 1220 has an inner edge angle 1240, which is the angle between the groove 1220 and the inner edge tangent 1230 of the groove 1220 contacting the inner edge 1270. The groove 1220 also has an outer edge groove angle 1260, which is the angle between the groove 1220 and the outer edge tangent 1250 of the groove 1220 contacting the outer edge 1280. The inner edge groove angle 1240 can be 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 degrees. Similarly, the outer edge groove angle 1260 can be 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 degrees. Each of the grooves in the side bushing 1210 has a groove radius of curvature 1290. The groove radius of curvature 1290 can vary along the groove and can be measured at a centerline path, where the centerline path is the middle of the groove between the inner edge 1270 and the outer edge 1280. The size of the groove radius of curvature 1290 can vary based on the size of the side bushing 1210, with larger side bushings 1210 having larger groove radius of curvature 1290. The groove curvature radius 1290 can be expressed as a percentage of the outer diameter of the side bushing 1210, and can be 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35%. The groove curvature radius 1290 as a percentage of the outer diameter can also be expressed as a range, such as 30% to 32%, 25% to 35%, 30% to 40%, or 25% to 40%.

[0110] Although the aforementioned grooves are recessed into the surface of the bushing, alternative bushings may have grooves protruding from the surface of the bushing. Protruding grooves may also have characteristics similar to recessed grooves, such as varying protrusion distances on the bushing surface. Protruding grooves may also have a protruding distance profile, similar to the depth profile of recessed grooves. The cross-section of the protruding groove may also vary and can be, for example, a square, rectangle, rounded square, rounded rectangle, semicircle, semi-ellipse, V-shape, flat semicircle, flat semi-ellipse, flat V-shape, W-shape, or some other shape, including possible combinations of the aforementioned cross-sections.

[0111] One potential problem with using protruding grooves is that the grooves may wear down, leaving flat areas on the bushing surface. These flat surfaces may then need to be planed. To overcome this problem, the bushing surface can use a combination of recessed and protruding grooves, such as alternating recessed and protruding grooves. Once the protruding grooves wear down, the recessed grooves will continue to provide the aforementioned benefits.

[0112] In one instance, the groove described above may have a varying curvature or radius. The radius of the groove may vary between the inner and outer edges. In one instance, the radius of the groove may gradually change between the inner and outer edges as the radius increases or decreases. In another instance, the radius of the groove may be modified in one or more discontinuous steps between the inner and outer edges. In yet another instance, the groove may have a constant radius.

[0113] advantage

[0114] As mentioned above, one advantage of patterned or slotted side bushings is that they reduce localized wear or planing compared to flat side bushings. Specifically, side bushings with arcuate grooves curving in the opposite direction to the impeller's main blades reduce planing compared to flat side bushings. This reduction in planing allows for extended operating time for the centrifugal pump between maintenance downtimes to replace or even inspect the side bushing for wear. Reduced maintenance requirements can lead to lower operating costs for the centrifugal pump because the lifespan of the side bushing can be increased. Increased pump availability is also possible.

[0115] Throughout the specification and the subsequent claims, unless the context otherwise requires, the word “comprise” and its variations such as “comprises” or “comprising” shall be understood to imply inclusion of the said integer or step or a set of integers or steps, but not to exclude any other integer or step or a set of integers or steps.

Claims

1. A side liner for a centrifugal slurry pump having main pumping vanes, the side liner comprising: a centrally located bore; and at least four grooves for disrupting flow of a mineral slurry on a surface that contacts the mineral slurry pumped by the centrifugal slurry pump, each of the at least four grooves being an arc extending radially from an inner edge of the surface near the bore to an outer edge of the surface and having a beginning and an end between the inner edge and the outer edge, wherein the depth of each of the at least four grooves is deepest at a middle region between the inner edge and the outer edge and shallowest near the inner edge and the outer edge.

2. The side liner of claim 1, wherein the curvature of the arc is in a parallel plane of the surface.

3. The side liner of claim 1, wherein the depth of each of the at least four grooves decreases from the middle region toward the outer edge and from the middle region toward the inner edge.

4. The side liner of claim 1, wherein the curvature of each of the at least four grooves is substantially similar to a curvature of the main pumping vanes of an impeller.

5. The side liner of claim 1, wherein each of the at least four grooves is gradually shallower between the middle region and the outer edge and between the middle region and the inner edge.

6. The side liner of claim 1, wherein a width of each groove is greater at a middle region between the outer edge and the inner edge of the surface than at regions near the inner edge and the outer edge of the surface.

7. The side liner of claim 1, wherein the at least four grooves are recessed grooves and protruding grooves.

8. The side liner of claim 1, wherein the side liner is a front side liner, or wherein the side liner is a back side liner.

9. A centrifugal slurry pump having the side liner of claim 1.

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