RU109236U1 - CENTRIFUGAL PUMP WITH TWO-SIDED INPUT WHEEL - Google Patents

Abstract

The utility model “Centrifugal Pump with Impeller of Two-Way Entrance” refers to the hydraulic engineering industry and can be used to supply water in heating networks. The pump housing contains the upper part (cover) and the lower part. The semi-spiral approach and spiral exit are formed by cavities in the upper and lower parts. The horizontal housing connector is sealed with fiber-based (FA) core material. A stand-alone device for cooling mechanical seals includes a distributor mounted on the cover for selecting a pumped medium, as well as manifolds and throttle washers for supplying it to the chambers of mechanical seals. Slotted rings of the impeller seals are made of wear-resistant material. Upstream axle wheels are installed in front of the impeller. The technical result is an increase in the reliability and durability of the pump.

Description

The utility model relates to the field of hydraulic engineering, namely, to centrifugal single-stage pumps and can be used to supply water in heating networks.

A well-known type CE pump is a centrifugal, single-stage with a double-acting inlet impeller, a pump housing with a horizontal connector, cast iron with a semi-spiral inlet and a spiral outlet. The rotor bearings are rolling bearings with liquid lubrication, one of which perceives a radial load, and the second - radial and residual axial loads. Shaft end seals - stuffing box type. [Pumping equipment of nuclear plants / Under the general editorship of PNPak. M .: Energoatomizdat, 2003 - p.333].

Significant disadvantages of such a pump include:

- the use of the packing does not reduce the leakage of the pumped medium and power loss, which affects the reliability of the pump;

- if it is necessary to operate the pump at low values of the allowable cavitation margin, the existing design does not provide the necessary anti-cavitation qualities and limits the scope of the pump,

The closest in design is a pump type NML, which eliminated the above disadvantages. By design, the pump is a single-stage centrifugal pump with an impeller of a two-way inlet containing a housing consisting of an upper part (cover) and a lower part, which form a horizontal connector, sealed with gasket material, a half-spiral inlet, and a spiral outlet. The shaft end seals are mechanical end seals with a device for cooling them with a pumped medium. The shaft rests on rolling bearings. Upstream axle wheels are installed in front of the impeller. [Malyushenko V.V. Dynamic pumps: Atlas. - M.: Mechanical Engineering, 1984, - p.21, Fig. 144].

The operating experience of such a pump revealed the following disadvantages:

- mechanical mechanical seals are cooled by supplying them with a pumped medium through collectors directly from the pressure cavity in the cover through two openings made in the pressure part of the cover. These places of fluid withdrawal are subject to erosion erosion and corrosion wear, exacerbated by the possibility of leakage of the working medium, which causes a decrease in the reliability of the pump;

- the use of gaskets for sealing the horizontal connector of the pump casing asbestos-containing material (paronite), along with the failure to meet the requirements for environmental friendliness of the material, reduces the reliability of the pump due to the low strength characteristics of the material. Leaks in the area of the horizontal connector, due to the properties of the gasket material and leading to leaks of the working medium, also increase the corrosive wear of the connected elements of the housing.

The task to which the claimed utility model is directed is to increase the reliability of the pump and increase its durability by reducing the leakage of the working environment.

The technical result is achieved in that in a centrifugal pump with an impeller of a two-way inlet, comprising a housing consisting of an upper part (cover) and a lower part forming a horizontal connector sealed with gasket material, a half-spiral inlet and a spiral outlet, upstream axial wheels mounted in front of the working mechanical seals of the mechanical type, equipped with a device for cooling, as end seals of a shaft supported by rolling bearings, a mechanical cooling device mechanical seals of the mechanical type are equipped with a distributor for the selection of the pumped medium located on the pump cover, and the gasket material for sealing the horizontal connector of the pump housing is a fiber-based material, for example, AFM 34 material.

The installation of a distributor for the selection of the pumped medium located on the pump cover allows reducing the number of holes on the cover to one, which reduces erosive and corrosive wear of the cover by reducing the possibility of leakage of the working medium and, as a result, corrosion wear at the location of the holes, and therefore increases the reliability and durability of the pump.

The use of fiber-based gasket material for sealing the horizontal connector, for example, AFM 34, improves the tightness of the pump working cavity due to the high elastic properties of the environmentally friendly material and its ability to withstand high pressure, which helps to prevent leakage of the working medium in the zone horizontal connector and, therefore, corrosive wear of the upper and lower parts of the housing, which increases the reliability and durability of the pump.

The utility model is illustrated in the figure, which shows a longitudinal section of a centrifugal pump with an impeller of a two-way inlet.

The centrifugal pump contains a housing, consisting of the upper part of the housing (cover) 1 and the lower part of the housing 2, forming a horizontal connector, sealed with a fiber-based cushioning material, for example, AFM 34 material (not shown in the figure).

The semi-spiral inlet 3 and the spiral outlet 4 are formed by cavities in the upper part of the housing (cover) 1 and the lower part of the housing 2. The impeller of the double-sided input 5 and the upstream axial wheels 6 are mounted on a shaft 7, which is supported by rolling bearings 8. Slot rings 9 of the impeller seals 5 are made of wear-resistant material. The end seals 10 of the shaft 7 - mechanical end type. A device for cooling mechanical seals 10 includes a distributor 11 mounted on the cover 1 for selecting a pumped medium, as well as manifolds 12 and throttle washers 13 for supplying it to the chambers of mechanical seals 10.

The pump operates as follows. When the shaft 7 is rotated from the drive motor, the fluid pumped through the floor is a spiral supply 3, the upstream axial wheels 6 enter the blades of the impeller of the bilateral input 5 and exit the spiral outlet 4 under the pressure created by the impeller 5.

The utility model allows to reduce the leakage of the working medium during the operation of the pump, which reduces corrosion on the casing elements of the pump and increases the reliability and durability of its operation.

Claims (2)

1. A centrifugal pump with an impeller of a two-way inlet, comprising a housing consisting of an upper part (cover) and a lower part forming a horizontal connector, sealed with gasket material, a semi-spiral inlet and a spiral outlet, upstream axial wheels mounted in front of the impeller and equipped with a device for cooling mechanical seals of mechanical type as end seals of a shaft supported by rolling bearings, characterized in that the device for cooling mechanical seals tor The centrifugal type is equipped with a distributor for the selection of the pumped medium located on the pump cover. 2. The pump according to claim 1, characterized in that the cushioning material for sealing the horizontal connector is a fiber-based material, for example AFM 34.