RU8420U1 - ONE-STAGE CENTRIFUGAL PUMP - Google Patents

Abstract

A single-stage centrifugal pump containing a front bearing and a rear bearing, which is a sliding bearing, a rotor with seals and an impeller of a two-sided input installed in the housing, as well as an inlet and an outlet nozzle, characterized in that two pipelines are additionally introduced into the device for supplying from the outlet nozzle to bearings of the lubricating fluid, which is the pumped fluid, two hydrofoils located towards each other, installed, like the bearings, in the housing, as the front under Ipnik used a plain bearing, which is closed by a cover with the mentioned seal installed in it, made by the end, and the rear bearing is closed by a blank cover mounted on the sharpening of the housing, while the bearings are made of antifriction material, and their covers have pipelines of calibrated cross-section to drain the pumped liquid from hidropyat to the inlet pipe.

Description

ONE-STAGE CENTRIFUGAL PUMP

The utility model relates to power engineering, in particular, to single-stage horizontal centrifugal pumps U can be used for pumping water, oil, oil products.

Existing centrifugal pumps can be divided into the following two groups. single and double entry pumps. At the same time, with comparable dimensions, the pumps of the first group pump liquid in approximately half the volume compared to the second, but at a higher pressure. The proposed pump belongs to the second group, which has a wide and predominant use in the power system, at U power plants in the housing and communal services.

Known two-stage centrifugal pump SI, belonging to the first group, containing a vertically split housing, in which two impellers are mounted, mounted on a shaft with two bearings - sliding bearings with rubber seals, a rolling bearing, inlet nozzles directed in opposite directions, with the front a shaft bearing with a seal is located inside the housing.

The pump also contains a clean water supply system used to lubricate the plain bearings and a container with oil or grease to lubricate the rolling bearings.

This pump allows you to pump liquid containing solid particles (inclusions) by supplying clean water to the plain bearings. The axial forces in this pump are unloaded by a rolling bearing.

F04D 1/00 F04D 1/06 The disadvantages of the analogue are,

- design complexity associated with the use of a rolling bearing and a clean water supply system from an external source;

- the complexity of operation, due mainly to the rapid destruction of the rolling bearing, leading to the subsequent destruction of rotor parts and impellers, as well as the need to use lubricating fluid;

- low reliability as a result of the specified destruction of structural parts U the use of short-lived rubber seals.

The closest in technical essence and the achieved result to the proposed pump is a single-stage centrifugal pump C23, belonging to the second group, containing a front angular contact rolling bearing, a rear plain bearing and a rotor with two seals installed in the housing U a double-sided impeller with different sealing rings diameter, as well as inlet and outlet nozzles. In the pump, the rolling bearing is made of steel, and the sliding bearing is made of babbitt, as seals are used I gland seals. Oil and grease containers are also included in the device to lubricate these bearings.

The prototype pump C2I1 provides a greater unloading of axial forces. U has a less complicated design due to the simplification of bearing assemblies, as well as lower cost.

However, its disadvantages are

-the complexity of the design, due, despite the decrease in the number of bearings compared to analogue C13, the presence of a rolling bearing itself, requiring lubrication

2

The technical problem to be solved by the proposed utility model was the development of a single-stage centrifugal pump, which allows to simultaneously abandon the use of oil as a lubricating fluid (the pumped fluid acts as a lubricating fluid) and to provide the possibility of increasing the overhaul period due to the operation of the pump with large wear of plain bearings, which does not result in to the destruction of the bearings themselves, as well as the rotor and impeller, as is the case when using a rolling bearing. The urgency of solving this problem is due to the great need in various sectors of the economy for fairly simple U-design, maintainable U highly reliable centrifugal pumps.

The problem is achieved in that in the well-known single-stage centrifugal pump containing a front bearing U, a rear bearing, which is a sliding bearing, a rotor with a seal installed in the housing and a double-entry impeller, as well as an input and output nozzle, according to the utility model, additionally two pipelines were introduced for supplying from the outlet pipe to the bearings of the lubricating fluid, which is the pumped fluid, two hydrofoils located towards each other, Mounted, like bearings, in the housing, a sliding bearing is used as a front bearing, which is closed by a cover with the mentioned seal installed in it, made by an end face, and the rear bearing is closed by a blind cover mounted on the body sharpening, while the bearings are made of antifriction material, and their covers have calibrated cross-section pipelines to divert the pumped liquid from the hydrofoils to the inlet pipe. with One of the essential features of the proposed utility model is the introduction of two additional hydrofoils. This allows the axial forces to be completely unloaded, and therefore not to control the axial movements of the rotor, to refuse to use the angular contact rolling bearing, oil for its lubrication U, as a result, to simplify the design pump, its operation, and also increase reliability. The location of the hitchhikers is critical. Only their arrangement towards each other in the pump casing makes it possible to unload axial forces from possible off-design disturbances and automatically maintain a given axial take-off. The location of the bearings in the pump housing and the use of a sliding bearing as the front bearing makes it possible to use the pumped liquid as a lubricant, which is supplied through two pipelines introduced additionally into the pump from the outlet pipe, that is, refuse oil lubrication, shorten the inter-rotor length, which helps to increase its rigidity, and therefore helps to exclude vibration with resonant frequencies, leading to the destruction of bearings and rotor. Another significant feature is the performance of the HUKOB sliding bearings made of anti-friction material. In the proposed design, this is the only possible material, since at the time of start-up, free rotation of the rotor should be ensured without the supply of lubricant. Also an essential group of signs are signs that characterize bearing caps.

An end seal is installed in the front bearing cover, which is not sensitive to the radial runout of the rotor, does not require maintenance, unlike the stuffing box, which as a result improves the reliability of the pump as a whole,

Finally, the last significant sign is the presence of pipelines to divert the pumped liquid from the discharge chambers of the hydrofoils to the inlet pipe.

These pipelines should have a calibrated cross-section, since only in this case the automatic operation of the hydrofoils located towards each other is ensured.

The proposed interdependent features in the aggregate are necessary and sufficient to solve the task, that is, they are significant.

The technical essence of the utility model is additionally illustrated by a figure, which shows the proposed pump in section. The following notation I is accepted in the figure

1- pump housing

2- rotor

3- impeller

4 front bearing

5- rear bearing

6- hydropaths of the front bearing

7- hydropaits of the back bearing

8- front bearing cover

9- rear bearing cover

10-face seal

11- pipelines for supplying the pumped liquid; all of the above units are designed for I-housing 1 for organizing the movement of fluid and for fixing pump assemblies; rotor 2 for impeller 3 for pumping fluid; plain bearings 4,5 for supporting the rotor along the axis of rotation J - 6.7 hydrofoils for unloading axial forces and limiting axial displacements of the rotor in both directions; -the front bearing cover 8 is the installation site of the mechanical seal Srotor-case5, as well as the front hydrofoam discharge chamber The bearings; - the rear bearing cap 9 is the unloading chamber of the rear bearing hydrofoam - the end seal 10 prevents leakage of the pumped fluid at the rotor-housing interface — pipelines 11 for supplying the pumped fluid to the bearings; -pipelines 12 for draining the pumped liquid from the discharge chambers of the hydrofoils; -the outlet pipe 13 for selecting the pumped liquid; -inlet pipe 14 for supplying the pumped liquid. The pump works in a fashionable way. When the impeller 3 rotates, a liquid with a pressure of P x. falls on his inputs. The energy of the wheel 3 is transferred to the fluid and there is pressure at the wheel outlet. Part of the fluid is taken from the outlet pipe 13 and the sub-pipelines 11 to the sliding bearings 4, 5.

u balancing the rotor in the axial direction, the fluid enters the bearing caps 8.9, which are discharge chambers, U is discharged through pipelines 12 to the pump inlet 14. Thus, the interaction of all pump components ensures its stable operation in a given mode,

An example of a specific implementation.

In the manufacture of the proposed pump, the pump rotor D-500 was used, on which the impeller D-500 was installed in its own housing. Plain bearings made of antifriction material of the type K15UV-5 or K15M-5 were installed in the bores of the pump casing of the indicated brand, intended for stuffing box seals. Two hydrofoils with a diameter of 80 mm were also installed in the pump casing, directed towards each other. The front bearing was closed by a cover with a mechanical seal type 6AR-7OE. The rear bearing was closed by a blank cover mounted on the body sharpening. Holes were drilled for installing pipelines at the inlet and outlet nozzles for supplying the pumped liquid to the bearing grease.

The manufactured centrifugal pumps were tested in real conditions at the South TPP Lenenergo SAkt N 31-01 / 770 from 08/05/94

attached J for pumping the following hot water liquids with

oo

temperature up to 160 C, oil with a temperature of 22 C. Pumping volumes were; Q 500 m / h, pressure 9 kgf / cm2.

In the process, the inventive centrifugal pump, indeed, did not require either clean water or lubricating fluid. The pump worked for ten thousand hours and never failed. At the same time, constant monitoring of the state of its nodes was not required.

Thus, as the tests showed, the proposed single-stage centrifugal pump, in comparison with the prototype, is indeed less complex in design, much simpler to operate - does not require the supply of clean water and lubricating fluid, as well as control over the flow of the latter, U is extremely reliable ,

-increases the stiffness of the shaft by reducing the inter-support length of the rotor;

- Prevention of the destruction of structural units due to the possibility of timely repair

in the prototype there is an instant destruction of the rolling bearing, and the sliding bearing is characterized by a gradual destruction that can be tracked,

An important advantage of the proposed pump is the automatic unloading of axial forces due to the use of hydrofoils, which is impossible when unloading is usually carried out by a rolling bearing,

A serious advantage of this pump is also an increase in fire safety due to the exclusion of the use of oil products as lubricants.

The last important technical and economic advantage is the lower cost of the claimed pump and the cost of its operation.

Currently, preparations are underway for the industrial production of these pumps.

LITERATURE

1. Two-stage centrifugal pump. Author's certificate N 186289. Russia, F04D1 / 06, authors V.A. Tatkov, P.I. Yurin, P.P. Vershinin, publ. 09/12/1966, Bull. M 18.

2. Centrifugal pump. Certificate of authorship

N 979706, Russia, F04D1 / 00, authors S.F. Kadygrob, E.P. Kreimer, V.N.Kolomets, publ. 12/07/1982, Bull. M 45

Claims (1)

A single-stage centrifugal pump containing a front bearing and a rear bearing, which is a sliding bearing, a rotor with seals and an impeller of a two-sided input installed in the housing, as well as an input and output nozzle, characterized in that two pipelines are additionally introduced into the device for supplying from the output nozzle to bearings of the lubricating fluid, which is the pumped fluid, two hydrofoils located towards each other, installed, like the bearings, in the housing, as the front under Ipnik used a plain bearing, which is closed by a cover with the mentioned seal installed in it, made by an end seal, and the rear bearing is closed by a blind cover mounted on the sharpening of the housing, while the bearings are made of antifriction material, and their covers have pipelines of calibrated cross-section for draining the pumped liquid from hidropyat to the inlet pipe.