Front side cover for a pump

Description

FRONT SIDE COVER FOR A PUMP TECHNICAL FIELD

[001] The present invention relates to front side linings, in particular, a front side lining for a centrifugal slurry pump. FUNDAMENTALS OF THE TECHNIQUE

[002] Centrifugal slurry pumps typically include a pump casing comprising a main casing, or volute, and one or more side casings. An impeller is mounted for rotation within the main casing around an axis of rotation. The main casing has a discharge outlet and an inlet that is on one side of the main casing and coaxial with the axis of rotation of the impeller. One of the side casings forms an inlet and is often referred to as a front side casing or a throat bushing.

[003] For centrifugal slurry pumps, the throat bushing is where some of the most erosive wear occurs. To reduce wear, the throat bushing can be designed with extra thickness and can also be cast from a particular material.

[004] In some cases, for example, if the thickness is greater than the standard, casting the throat bushing in a single piece will be difficult because the alloys tend to shrink and crack during the cooling process.

[005] In addition, more erosive wear can occur on the throat bushing between an impeller surface that faces an inner face of the throat bushing where there is a small gap (sometimes referred to as a suction gap) to prevent friction of the rotating impeller against the throat bushing. Wear on the suction gap occurs on a radial inner surface of the throat bushing. In current designs, even if only the radial inner surface of the throat bushing adjacent to the suction gap wears, the entire throat bushing is replaced, resulting in greater waste, as the remainder of the throat bushing is still within operating specifications.

[006] It is among the objectives of the embodiments of the present invention to overcome or mitigate one or more of the above disadvantages or other disadvantages of the prior art or to provide a useful alternative. Petition 870260070587, dated 07 / 16 / 2026, page 10 / 38 2 / 8 SUMMARY OF THE INVENTION

[007] This summary is provided to present a selection of concepts that are better described below in the detailed description. This summary is not intended to identify indispensable features of the claimed object, nor is it intended to be used as an aid in limiting the scope of the claimed object.

[008] According to a first aspect, a front side casing is provided for a centrifugal slurry pump. The front side casing comprises an inner part and an outer part. The inner part comprises an annular body extending from an outer end to an opposite inner end and a raised portion extending radially outward at the opposite inner end of the annular body. The raised portion has an inner surface and an opposite outer surface defining an axial thickness between them. The outer part is an annular ring with an inner diameter dimensioned to receive the raised portion of the inner part. The outer part has an inner surface and an opposite outer surface defining an axial thickness between them that is equal to or less than the axial thickness of the raised portion.The protruding portion of the inner part is received within the outer part to form the front side covering, with the outer end of the annular body extending longitudinally, passing through the opposite outer surface of the outer part.

[009] Preferably, the front side panel includes connection means for connecting the outer and inner parts.

[0010] Preferably, the annular body is formed from a first material and the outer part is formed from a second material.

[0011] Preferably, the front side covering includes an annular reinforcement ring that is attachable to the outer surface of the outer part and to the outer surface of the raised portion.

[0012] Preferably, the front side panel also includes a sealing element fixed to a radial outer face of the outer part. The sealing element may also be fixed to a radial outer face of the reinforcing ring.

[0013] According to a second aspect, a front side casing assembly is provided for a centrifugal pump. The front side casing assembly includes an inner part that has an annular body from a Petition 870260070587, dated 07 / 16 / 2026, p. 11 / 38 The front side panel assembly includes a 3 / 8" outer end to an opposite inner end and a radially outward-extending raised portion at the opposite inner end with an axial thickness. The front side panel assembly further includes an outer part with an inner diameter dimensioned to receive the raised portion of the inner part and an axial thickness equal to or less than the axial thickness of the raised portion, wherein the raised portion of the inner part is received within the outer part to form the front side panel with the outer end of the annular body extending longitudinally outward, passing through the outer part. The front side panel also includes an annular reinforcing ring fixed to an outer surface of the raised portion and an outer surface of the outer part to fix the inner and outer parts together, and a sealing element fixed to a radial outer face of the outer part and a radial outer face of the annular reinforcing ring.

[0014] According to a third aspect, a centrifugal pump is provided. The centrifugal pump comprises a pump casing and an impeller positioned within the inner casing of the pump casing. The impeller is connected to a drive shaft that imparts rotation to the impeller around an axis of rotation. The centrifugal pump also comprises a front side casing assembly according to the second aspect, wherein the inner end of the front side casing is positioned adjacent to the impeller and wherein the reinforcing ring is fixed to the pump casing. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] These and other aspects of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows an exploded view of the front of a front side cladding according to the present invention; Figure 2 shows an exploded sectional view of the front side cladding of Figure 1; Figure 3 shows an exploded view of the rear part of the front side cladding of Figure 1; Figure 4 shows a front view of the front side cladding of Figure 1; and Petition 870260070587, dated 07 / 16 / 2026, page 12 / 38 4 / 8 Figure 5 shows a sectional view along line AA of the front side cladding, as shown in Figure 4; and Figure 6 shows a sectional view along line BB of the front side cladding, as shown in Figure 4. DETAILED DESCRIPTION OF SPECIFIC MODALITIES

[0016] Figures 1, 2 and 3 show exploded views of a front side cover 10, or throat bushing, according to an embodiment of the present invention. The front side cover 10 extends longitudinally along an axis xx and includes an inner part 12, an outer part 14, a reinforcing ring 16 and a sealing element 18. During use, the front side cover 10 is housed within a pump casing (not shown) at the front end of the pump casing adjacent to an inlet hole (not shown). The front side cover 10 is attached to a suction cap (not shown) of the pump casing (not shown) such that an inner end 24 of the front side cover 10 is oriented toward and adjacent to an impeller (not shown) housed within the pump casing (not shown).

[0017] The inner part 12 includes an annular body 20 extending along the xx axis from an outer end 22, which, during use, is oriented outward from the pump casing (not shown), to the opposite inner end 24, which, during use, is oriented inward from the pump casing (not shown) and, during use, is adjacent to the impeller (not shown). The inner part 12 further includes a raised portion 26, indicated by the dashed line portion shown in Figure 2, which extends radially outward from the annular body 20 at the opposite inner end 24. In this embodiment, the inner part 12 includes a step formation 28 positioned adjacent to an outer face 30, which is oriented towards the outer end 22 of the raised portion 26 and extends radially outward from the annular body 20. The step formation 28 has a smaller outer diameter compared to the outer diameter of the raised portion 26.The raised portion 26 includes an inner face 32, oriented towards the inner end 24, with an axial thickness, t1, measured between the inner face 32 and the outer face 30.

[0018] The outer part 14 is an annular ring that is dimensioned to receive the raised portion 26 of the inner part 12. In other words, the outer part 14 has Petition 870260070587, dated 07 / 16 / 2026, page 13 / 38 5 / 8 an internal diameter dl dimensioned to accommodate the raised portion 26 of the internal part 12. The external part 14 has an external face 34, oriented towards the external end 22, and an internal face 36, oriented towards the internal end 24, with an axial thickness, t2, measured between the external face 34 and the internal face 36 that is equal to or less than the axial thickness, t1, of the raised portion 26. In other words, the external part 14 has an axial thickness similar to or less than the raised portion 26 of the internal part 12 and, as such, only the raised portion 26, or part of the raised portion 26, is received within the external part 14 with the remainder of the internal part extending longitudinally, passing through the external part 14.

[0019] The annular body 20 of the inner part 12 further defines a hole 38 that extends longitudinally through the annular part 20 along the xx axis. The hole 38 includes a substantially cylindrical outer portion 40, with an inner diameter d2, and a profiled inner portion 42, with an inner diameter d3. The inner diameters, d2 and d3, may be determined by the application, or type of fluid paste. It should be noted that the profiled inner portion 42 may be substantially cylindrical, frustoconical in shape, or any alternative shape. The diameter d3 of the profiled inner portion 42 may be smaller than the diameter d2 of the outer portion 40, so that an internal step formation 43 is defined between the inner portion 42 and the outer portion 40. Advantageously, the outer portion 14 may accommodate inner portions 12 with different inner diameters and / or different profiled inner portions (e.g., reduced eye or standard eye) for different service conditions.

[0020] The inner part 12 and the outer part 14 can be cast in different alloys or molded in rubber to meet different wear objectives. For example, due to internal recirculation and variable service operating points, the inner part 12 may experience more wear and different wear patterns than the outer part 14.

[0021] Furthermore, it is possible to independently replace the internal parts 12 or external parts 14 if, for example, one wears out faster than the other.

[0022] The reinforcing ring 16 is fixed to the outer face 30 of the raised portion 26 and to the outer face 34 of the outer part 14. In the example embodiment with the thickness Petition 870260070587, dated 07 / 16 / 2026, page 14 / 38 6 / 8 axial t2 of the outer part 14 being smaller than the thickness t1 of the raised portion 26, the reinforcing ring 22 includes a profiled inner wall 44 that is turned and placed against the outer faces 30 and 34 of the raised portion 26 and the outer part 14.

[0023] The inner part 12 includes a plurality of openings 46 located on the outer face 30 of the raised portion 26. The plurality of openings 46 are spaced circumferentially around the hole 38. Each of the plurality of openings 46 can be arranged to receive a threaded spacer 48 (shown in Figure 5). Each spacer 48 can also be arranged to receive, by threading, a fastener 50 to secure the reinforcing ring 16 to the inner part 12. It should be noted that spacers with variable axial lengths can be used. Advantageously, the two-part throat bushing and the use of spacers with variable axial lengths allow the inner part 12 to be adjusted forward, in other words, inward, so that a clearance between the innermost point of the inner part and the impeller housed within the pump casing is reduced or maintained independently of wear, regardless of the outer part 14.Adjusting the inner part 12 forward further reduces recirculation, which in turn reduces wear.

[0024] The outer part 14 includes a plurality of protrusions 52 that are circumferentially spaced and extend from the outer face 34 of the outer part 14. The reinforcing ring 16 may include corresponding recesses 54 into which the plurality of protrusions 52 fits. The plurality of protrusions 52 includes threaded openings 56 into which fasteners 58 are threaded to secure the reinforcing plate 16 to the outer part 14.

[0025] During use, the reinforcing ring 16 includes a plurality of openings 60 on an outer face 62 of the reinforcing ring in which fasteners are received, in a threaded manner, to attach to a cover plate and, subsequently, the inner part, the outer part and the reinforcing ring to the pump casing or to the cover plate.

[0026] The sealing element, in this embodiment, a rubber seal 18, is fixed or molded to a radially external surface 64 of the outer part 14 and a radially external surface 66 of the reinforcing ring 16 using Petition 870260070587, dated 07 / 16 / 2026, page 15 / 38 7 / 8 hot press molding to ensure the bond between the outer part 14 and the reinforcing ring 16 and prevent any leakage. The sealing element 18 further creates a fluid-tight seal between the outer part 14 and the reinforcing ring 16 and the pump casing (not shown).

[0027] Unlike current front side panels, where the reinforcement plate, sealing member, and outer part are of unitary construction, the present invention provides a front side panel where these components are formed separately, which allows a throat bushing with a thickness greater than the standard to be cast as separate pieces (inner and outer parts) to alleviate the problems encountered due to the tendency of alloys to shrink and crack during the cooling process. The separate components of the front side panel, moreover, allow the different components to be constructed from different materials and individual replacement of the separate components.

[0028] The above describes only some embodiments of the inventions, and changes, modifications, additions and / or alterations may be made without departing from the scope of the embodiments disclosed, the embodiments being illustrative and not restrictive. LIST OF REFERENCE NUMBERS front side cladding inner part outer part reinforcing ring sealing element annular body of the inner part outer end inner end raised portion of the inner part step formation of the inner part Petition 870260070587, dated 07 / 16 / 2026, page 16 / 38 8 / 8 outer face of the raised portion inner face of the raised portion outer face of the outer part inner face of the outer part hole of the annular body outer portion of the hole profiled inner portion of the hole step formation of the hole profiled inner wall of the reinforcing ring opening in the inner part spacers fasteners protrusions of the outer part recesses of the reinforcing ring openings in the protrusions fasteners openings in the reinforcing ring outer face of the reinforcing ring radially outer surface of the outer part radially outer surface of the reinforcing ring Petition 870260070587, dated 07 / 16 / 2026, page 17 / 38

Claims

1. Front side casing for a centrifugal slurry pump, the front side casing characterized in that it includes: an inner part having an annular body extending from an outer end to an opposite inner end and a raised portion extending radially outward from the annular body at the opposite inner end, the raised portion having an axial thickness; and an outer part with an inner diameter dimensioned to receive the raised portion of the inner part and outer and inner surfaces defining an axial thickness between them, which is equal to or less than the axial thickness of the raised portion, wherein the raised portion of the inner part is receiveable within the outer part to form the front side casing with the outer end of the inner part extending longitudinally outward, beyond the outer surface of the outer part.

2. Front side panel, according to claim 1, characterized in that it further includes an annular reinforcing ring to secure the inner and outer parts.

3. Front side panel, according to claim 1, characterized in that the annular reinforcing ring is fixed to an outer surface of the protruding portion of the inner part and an outer surface of the outer part.

4. Front side cladding, according to claim 1, characterized in that the inner part is formed from a first material and the outer part is formed from a second material.

5. Front side cladding, according to any of the preceding claims, characterized in that it further includes a sealing element fixed to a radial outer face of the outer part.

6. Front side panel, according to claim 5, characterized in that the sealing element is further fixed to a radial outer face of the annular reinforcement ring.

7. Front side casing assembly for a centrifugal slurry pump Petition 870260070587, dated 07 / 16 / 2026, page 22 / 38 2 / 2, the front side casing assembly characterized in that it includes: an inner part having an annular body extending from an outer end to an opposite inner end and a raised portion extending radially outward from the annular body at the opposite inner end, the raised portion having an axial thickness;an outer part with an inner diameter dimensioned to receive the raised portion of the inner part and outer and inner surfaces that define an axial thickness between them equal to or less than the axial thickness of the raised portion, wherein the raised portion of the inner part is received within the outer part to form the front side cladding with the outer end of the inner part extending longitudinally outwards, beyond the outer surface of the outer part; an annular reinforcing ring fixed to an outer surface of the raised portion of the inner part and the outer surface of the outer part to fix the inner and outer parts together; and a sealing element fixed to a radial outer face of the outer part and a radial outer face of the annular reinforcing ring.

8. Centrifugal slurry pump, characterized in that it comprises: a pump casing; an impeller positioned within the inner casing of the pump casing, the impeller being connected to a drive shaft that imparts rotation to the impeller around an axis of rotation; and the front side casing assembly, as defined in claim 7, wherein the inner end of the front side casing is positioned adjacent to the impeller and wherein the reinforcing ring is fixed to the pump casing.

Images