RU57392U1 - BILATERAL INPUT PUMP - Google Patents

Abstract

The claimed technical solution of the double-entry pump relates to mechanical engineering and can be used in pumps with a semi-spiral inlet and a spiral outlet with a double helix. The double-entry pump includes stator and rotor parts. The stator part contains a housing 1 with a hydraulic cavity, with an inlet 2 and a pressure pipe (pressure pipe in the FIG. Not shown) and covers 3, 4. The rotor part includes a shaft 5 with an impeller 6 of the two-side input shaft 5 is connected to the stator part by sliding bearings 7 , 8, and a mechanical seal 9. The pump is equipped with two identical axial-force unloading units. The units are two rings 10, 11, and 12, 13 of a thrust bearing. Rings 10, 12 are fixed, mounted on the housing, and 11, 13 are movable relative to fixed 10, 12 mounted on to olesa. Between each other, rings 10, 11 and rings 12, 13 were formed along the throttling slots 14, 15, and a radial clearance 16, 17 was formed on both sides of the impeller 6 and the stator part. The annular cavities 18, 19, bearings 7, 8 are connected by channels ( in Fig. not shown) with the pressure part of the hydraulic cavity of the pump housing. An open seal 9 is installed on the open side of the shaft. 1 n.p. crystals, 4 FIG.

Description

The claimed technical solution, a double-inlet pump relates to mechanical engineering and can be used in pumps with a semi-spiral inlet and a spiral outlet with a double-scroll spiral, for example, in condensate second rise, emergency low pressure, double-inlet pumps, as well as in network pumps.

Known double-sided pump type D, comprising a housing with a hydraulic cavity, inlet and discharge nozzles and a cover mounted on the housing. The body and cover have a common horizontal connector with gasket between the flanges. End seals are integrated in the housing on both sides. The rotor part includes a shaft with an impeller of a two-sided input, and it is connected to the stator part by ball bearings installed in the remote part (outside the housing) on both its sides.

Such a case has a number of design flaws that negatively affect the technical result. So, the horizontal connector is blurred when the pump is running, in addition, when pumping a liquid having a high temperature, the connector is subjected to the action of internal forces arising, both in the housing and in the cover. The above reasons lead to a violation of the tightness of the connection and, as a result, there is a leak of pumped liquid. The use of ball bearings provides a short service life, and they are used in low-power pumps. Installing bearings outside the housing increases the distance between the bearings, which leads to shaft deflection, vibration and wear of the end seals. This also leads to depressurization of the pump.

A number of pumps are also known [2, 3, 4, 5], in which there is a horizontal connector between the housing and the cover, end seals are located in the housing, and remote sliding bearings are mounted with angular contact bearings.

Such pumps are designed for a larger load than the previously specified pump. However, all the disadvantages described above are inherent in this series of pumps. In addition, the use of a sliding bearing and an angular contact bearing increases and complicates the design of the assembly and does not eliminate the disadvantage of reducing the distance between the bearings. Along with the drawbacks, these pumps have an important advantage - a hydraulic cavity with a well-calculated and designed half-helical inlet and a spiral outlet with a double helix in the pump casing.

Given the positive qualities and the elimination of these shortcomings, the task was to design and manufacture an improved design pump by reducing the distance between the bearings of the sliding bearings, and without a horizontal connector between the housing and the cover, without violating the existing and practically tested geometry of supply and exhaust in the pump housing.

To solve this problem, a double-entry pump has been proposed, including a stator and rotor part, while the stator part contains a housing with a hydraulic cavity, inlet and discharge nozzles and covers, and the rotor part includes a shaft with a double-entry impeller and it is connected to the stator part by sliding bearings and a mechanical seal, with a radial clearance formed on both sides of the impeller and the stator part.

In contrast to the known, the inventive pump is equipped with two identical axial force unloading units located on both sides of the impeller and representing two rings, one of which

mounted on the outer side of the impeller inlet, and the other ring is located opposite the first, on the stator part, forming an end throttling slot between each other, in addition, sliding bearings located in the housing covers, the annular cavity of which is connected by a channel with the pressure part of the pump hydraulic cavity, in addition, the mechanical seal is mounted on the transmission side of the torque.

Distinctive features of a double-entry pump have a number of positive qualities that affect the technical result, namely:

- the pump is equipped with two identical nodes of the axial force unloading. The presence of two identical nodes of the axial force unloading allows you to compensate the axial force, both on the one and the other side with respect to the impeller caused by the operation of the pump. The cause of the axial force may be the heterogeneity of the fluid being pumped, the mechanical inclusions in it, and the imperfection of the geometry of the flow part of both the housing and the impeller.

- Unloading units are located on both sides of the impeller. Thus, the resulting axial force on the wheel is compensated in the immediate vicinity of the wheel. This means that the resulting axial force acts on the shaft only in the area of the wheel. The rest of the shaft is not valid.

- the axial force unloading units are two rings, one of which is installed on the outside of the impeller entrance, and the other ring is located opposite the first, on the stator part. This design is the most simple and technologically feasible. The units work like a thrust bearing.

- the installed rings form between themselves an end throttling gap. The specified gap is the size of the gap, which is necessary to move the rotor part when compensating axial force.

Thus, the presence of a throttling gap between the rings and a radial clearance between the stator part and the wheel, made it possible to combine the thrust bearing with the unloading device for axial shaft movement (hydraulic spot).

- plain bearings located in the housing covers. This allows you to reduce the distance between the axes of the bearings, which increases the stiffness of the shaft and eliminates or reduces its deflection. Positive effect on vibration and noise characteristics of the entire pump.

- the annular cavity of the plain bearings is connected by a channel with the pressure part of the hydraulic cavity. Since the pressure in the hydraulic cavity of the discharge part is greater than in any other part of the hydraulic cavity, a certain amount of pumped fluid flows through the annular cavity of the plain bearings. Thus, both bearings are lubricated and cooled.

- the mechanical seal is installed on the transmission side of the torque. This made it possible to simplify the design of the pump, reduce its dimensions and weight, since one end of the shaft has a mechanical seal, and the other end of the shaft is shortened and covered with a cover.

The distinguishing features listed above are necessary and sufficient to solve the task. All the distinguishing features are in a causal relationship with the result obtained and allow, at a high technical level, to create a design of a double-entry pump, in which

bearings are structurally combined with a hydraulic spot, the actions of which are aimed at balancing axial forces. In addition, plain bearings are integrated directly into the housing covers. This arrangement gives the wag rigidity. Compared with known pumps, the inventive is reduced in size and weight.

The essence of the technical solution is illustrated by the drawings:

In Fig.1 - shows a pump of a two-way input (sectional view);

figure 2 - callout I; Figure 3 - callout II;

figure 4 - callout III.

The double-entry pump includes stator and rotor parts. The stationary part comprises a housing 1 with a hydraulic cavity, with an inlet 2 and a pressure pipe (pressure pipe in Fig. Not shown) and a cover 3, 4. The rotor part includes a shaft 5 with an impeller 6 of the two-way inlet. The shaft 5 is connected to the stator part by sliding bearings 7, 8, and a mechanical seal 9. The pump is equipped with two identical axial force unloading units. The units are two rings 10, 11, and 12, 13 of a thrust bearing. Rings 10, 12 are fixed, fixed on the body, and 11, 13 are movable relative to fixed 10, 12 mounted on the wheel. Between themselves, rings 10, 11 and rings 12,13 formed along the throttling slots 14, 15, and a radial clearance of 16.17 was formed on both sides of the impeller 6 and the stator part. The annular cavity 18,19, the sliding bearings 7, 8 are connected by channels (not shown in Fig.) With the pressure part of the hydraulic cavity of the pump housing. On the open side of the shaft installed mechanical seal 9.

The double-sided pump operates as follows. The pumped liquid enters the inlet pipe 2, then it moves along the semi-spiral supply to the impeller 6 of the two-way entrance. A rotating wheel 6 under the action of centrifugal force gives additional energy to the pumped liquid, which through

a spiral outlet with a double helix spiral is sent to the discharge pipe. At the same time, a part of the working fluid exiting the impeller 6 passes into the end throttling slots 14, 15 through the radial clearances 16, 17. Thus, the movable and fixed rings 11, 13 and 10, 12, which formed the throttling slots 14, 15, are resistant. bearings perceiving axial force acting on the rotor part. In aggregate, the throttling slots 14, 15 and the radial clearance 16, 17 act as a hydrofoam, which automatically sets the impeller 6 to the optimal position. So, under the action of axial force on the rotor from right to left, the impeller 6 is shifted along the axis of rotation to the left - the end throttling slot 15 decreases. As a result, in the cavity between the end throttling slot 15 and the radial clearance 17, the fluid pressure increases, which counteracts the axial force. In an emergency situation, when the hydrofoil does not have time to react and counteract the axial force, the ring 13 mounted on the impeller 6 abuts against the ring 12 located on the stator part. Thus, the rings 12, 13 act as a thrust bearing, and the rings 10, 11, on the right side, form an enlarged throttling gap 14. Therefore, the liquid in the cavity between the throttling gap 14 and the radial clearance 16 is at a lower pressure and helps to move the rotor to the right .

When the rotor is moved to the right, the right side, i.e. rings 10, 11, a throttling slit 14 and a radial clearance 16. At the same time, the left part is unloaded, thereby helping to soften the rotor movement force.

Thus, self-regulation of the position of the impeller in the pump is ensured.

At the same time, the working fluid from the pressure part of the hydraulic cavity is fed into the annular cavity 18, 19 of the sliding bearings 7, 8 channels. This is due to the pressure difference in the pressure part of the hydraulic cavity and part of the lower pressure hydraulic cavity. Therefore, the pumped liquid provides lubrication and cooling for the plain bearings integrated in the housing covers.

On the output side of the shaft 5 from the pump, the mechanical seal 9 prevents fluid from flowing through the shaft.

Thus, the inventive double-entry pump is made with a new constructive solution, namely: plain bearings built into the housing covers, thrust bearings are located in the immediate vicinity of the impeller, while they are combined with a hydroheel.

Compared with the same type of pumps, the inventive pump is more technologically advanced in manufacture, easier to assemble, commission, and more reliable in operation.

Claims (1)

The double-entry pump, including the stator and rotor parts, moreover, the stator part contains a housing with a hydraulic cavity, inlet and discharge nozzles and covers, and the rotor part includes a shaft with a double-entry impeller and it is connected to the stator part by sliding bearings and mechanical seal, while a radial clearance is formed on both sides of the impeller and the stator part, characterized in that the pump is equipped with two identical axial force unloading units located on both sides of the impeller and representing two rings, one of which is installed on the outer side of the entrance to the impeller, and the other ring is located opposite the first, on the stator part, forming an end throttling gap between themselves, in addition, the annular cavities of the sliding bearings located in the housing covers are connected by channels with the pressure part of the hydraulic cavity of the pump, moreover, the mechanical seal is installed on the transmission side of the torque.