Centrifugal pump and method of adjusting the distance of the wear plate from the impeller of a centrifugal pump

Abstract

A centrifugal pump (1) for lifting clean water or water with suspended solids comprises a hollow body (2) defining a center axis (L) and having a front opening (3) and a volute (4) with a delivery port (5), an impeller (8) accommodated in the body (2) and designed to be coupled to a motor and having blades (9) whose tips (10) are substantially coplanar at an annular peripheral area (11). A cover (12) is also provided for closing the front opening (3), which consists of a flange (13) with a central portion (14) and a substantially radial peripheral portion (16), a substantially annular wear plate (19), rigidly joined to the flange (13) and located at a predetermined axial distance (di) from the annular peripheral area (11) of the impeller (8) and adjustment means (24) for controlled adjustment of the axial distance (d1) of the wear plate (19). The adjustment means (24) are mounted to the flange (13) and can be accessed from the outside, and are designed to both calibrate the axial position of the wear plate (19) and to lock the latter in the calibrated position. A method of adjusting the axial distance (d1) of the wear plate (19) from an impeller (8) in a centrifugal pump (1) is disclosed.

Description

technical field [0001] The invention is generally applicable in the field of fluid machinery, and in particular relates to a centrifugal pump for lifting clean water or water with suspended solids. [0002] The invention also relates to a method of adjusting the distance between the wear plate and the impeller of a centrifugal pump. Background technique [0003] Wear plates are known to be used in fluid machinery and centrifugal pumps and are coupled to the suction flanges of the covers to reduce their wear and prolong the life of the pump. [0004] In particular, a wear plate is mounted to the inner surface of the flange facing the impeller and shields the inner surface of said flange from suspended solids impinging thereon when the liquid is lifted. [0005] The wear plates are internally coated with a wear reducing material, such as Teflon, and are positioned at a predetermined axial distance from the impeller blades, known in the art as a "wear gap". [0006] This axia...

AI Technical Summary

Problems solved by technology

[0011] The first disadvantage of this arrangement is that it requires the operator to disassemble the pump body to fit the seals and adjust the wear clearance

[0012] This disadvantage increases the complexity of the maintenance and assembly procedures, thereby prolonging the overall process time

[0013] Another disadvantage is that it is often difficult to find seals of different thicknesses in the field

[0014] Another disadvantage is that rubber seals and Teflon rings have the property of deforming over time, leading to undesirable variations in the tolerances specified by the pump unit manufacturer

[0015] Another disadvantage is that seals and rings are prone to rapid wear and must be replaced periodically by the operator to ensure consistent pump performance

[0016] Another disadvantage is that the disassembly procedure involves removing the suction flange which is not connected to the pump unit and which must be moved using appropriate lifting equipment

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