RU18561U1 - MULTI-STAGE CENTRIFUGAL PUMP - Google Patents

Abstract

(54) Multistage centrifugal pump

(57) Use: pumping water into oil flaps to maintain reservoir pressure during oil production. The essence of the utility model: in a multisectional housing with inlet and outlet nozzles 5.6, a drive shaft 8 with impellers 9 according to the number of sections and an unloading disk O with a discharge chamber 11 is installed. The shaft 8 is sealed by double mechanical seals 12 with a locking fluid (mineral oil) , which circulates along the circuit 20, being cooled in the lower compartment 24 of the tank 21, where the refrigerator 22 is installed. In the upper compartment 23 of the tank connected to the pump inlet 5 and filled with working fluid, a rod 27 is attached, attached below the end to the membrane 25. The rod 27 is equipped with a load 29, the pressure of which through the membrane 25 to the shutter fluid in the lower compartment 24 provides an excess of pressure in the circuit 20 of the shutter fluid over the pressure of the working fluid in the pump. The inlet and outlet of the refrigerator 22 are in communication with the inlet pipe 5. On the pipe connecting the pipe 5 with the inlet of the refrigerator. throttle 32 is installed, behind which

1 s.p. f-ly, I ill. a drain chamber is connected to it

Description

2001100474

MULTI-STAGE CENTRIFUGAL PUMP

The utility model relates to pump engineering and can be used to pump water into oil beds during oil production in order to maintain reservoir pressure.

Known multistage centrifugal pump from the catalog Centrifugal pumps M., TsINTIkhimnefteman, 1975, p. 4.

It contains the inlet and outlet covers and a casing, sandwiched between them by means of tie rods, consisting of several sections. A drive shaft with impellers passes through the housing and covers in the number of sections and the front and rear end seals of the stuffing box type.

The known pump has low reliability due to stuffing box seals, which lose elasticity during operation.

The fragility of stuffing box packing leads to their frequent replacement, which in turn reduces the efficiency of the pumps.

Known multistage centrifugal pump from the book of A.I. Golubev Mechanical seals of rotating shafts, M., Mechanical Engineering, 1974, p. 200, fig. 155.

Iasos includes inlet and outlet valves and a housing with inlet and outlet nozzles sandwiched between them by means of couplers. The body is made of several sections docked between each other and the covers. A drive shaft with impellers installed one in each section passes through the corsus and covers. On the side of the output cover, a discharge disk is installed on the shaft with the formation of a drain chamber behind it.

To seal the drive shaft, double end seals are used as end seals with the supply of the shut-off fluid (mineral oil) from the tank and vice versa, but the circulation circuit including the throttle. There is a refrigerator inside the tank. The overpressure in the circulation circuit is ensured by a pump and a valve mounted on the circulation circuit.

IPC F04D 1/06

The disadvantage of the prototype is the low reliability due to the complex system of maintaining the pressure and temperature of the gate fluid in the end seals of the drive shaft.

The task, the solution of which is directed by a utility model, is to increase the reliability of a multistage centrifugal pump by improving the system for supplying a shutter fluid to double mechanical seals.

The specified technical result is achieved by the fact that in the well-known multistage centrifugal pump, it contains the inlet and outlet covers, the housing with the inlet and outlet nozzles sandwiched between them by means of couplers, made of several sections, passing through the housing by a drive shaft with impellers installed one at a time in each section, by a discharge disk on the side of the outlet cover with the formation of a drain chamber and mechanical end seals connected to the shutter fluid circuit, including a tank with a built-in refrigerator, according to a utility model, the tank cavity is divided into upper and lower compartments using a membrane ycTatmB above the refrigerator, the shutter fluid circuit is connected to the lower tank compartment, and a coaxial rod is installed in the upper compartment of the tank communicated with the pump inlet , the lower end of which is attached to the membrane, and the upper - brought out and supplied with cargo.

In addition, the inlet and outlet of the refrigerator are in communication with the pump inlet pipe, and a throttle is installed on the pipeline connecting the pump inlet pipe to the refrigerator inlet, after which a drain chamber is connected to it.

Due to the communication of the upper compartment of the tank with the pump inlet pipe and the additional force created by the load through the separation membrane to the shutter fluid in the lower compartment in the circulation circuit, the constant overpressure between the shutter fluid and the pumped liquid that is not pumped by the pump is necessary for the seal to work. Thus, the fluid pressure in the circulation circuit is provided due to the pressure of the working fluid itself. This simplifies the system and increases its reliability, as no additional energy is required, there is no need for control and regulation devices.

In addition, the working fluid is also used to cool the shutter fluid due to the communication of the inlet and outlet of the chilli ch.

The proposed multistage centrifugal pump is illustrated by drawings, where

in FIG. 3 - Diagram of the system for ensuring the seal operation.

A multistage centrifugal pump contains an inlet and an outlet cap 1.2 and a housing 4 clamped between them by means of ties 3 with an inlet and outlet nozzles 5, 6. The housing is made of several sections 7 joined together with the covers 7. The drive shaft passes through the housing and covers for 8 s 9 impellers installed one in each section. On the side of the output cover 2, an unloading disk 10 is installed on the shaft with the formation of a discharge chamber behind it 11. To seal the drive shaft, mechanical seals 12 are used as end seals.

The mechanical seals 12 are double (Fig. 2): the inner seal 13 is in contact with the working fluid, the seal 14 is external. Through the inlet and outlet openings 15 and 16, the seal is connected to the circulation fluid of the barrier fluid. To increase the efficiency of circulation, a built-in discharge element 17 in the form of a labyrinth-screw impeller is made. To collect the leakage of the chamber, chamber 18 with a nipple 19 outward.

The circulation fluid of the shutter fluid 20 (Fig. 3), indicated by the dashed line, includes a tank 21 with an integrated refrigerator 22. The cavity of the tank is divided into upper and lower compartments 23 and 24 with a membrane 25 mounted above the refrigerator. The circulation loop 20 is connected to the lower compartment 24 of the tank. The upper compartment 23 is connected to the pump inlet 5 by a pipeline 26. A rod 27 is installed coaxially in the upper compartment, the lower end of which is attached to the membrane 25, and the upper end is brought out through the seal 28 and is equipped with a load 29.

The inlet and outlet of the refrigerator 22 are in communication with the inlet pipe 5 of the pump by pipelines 30 and 31. A throttle 32 is installed on the pipe 31 connecting the pipe 5 to the refrigerator inlet, after which the drain chamber 11 is connected to it by a pipe 33.

A multistage centrifugal pump operates as follows.

During the rotation of the drive shaft 8, the working fluid enters through the inlet pipe 5 into the pump housing, where it is accelerated by the impellers 9 and, passing successively through all sections, cools down under the most pressure through the outlet pipe 6 to the consumer.

The axial forces acting on the pump shaft are absorbed by the discharge disk 10, which is under high pressure of the working fluid, which then merges through the drain chamber 11 to the pump inlet.

The shaft is sealed by mechanical seals 13 and 14, the space between which is filled with a barrier fluid (mineral oil). In order to avoid overheating of the seals, the shutter fluid is circulated by means of a screw impeller 17. The internal mechanical seal 13 is additionally washed by the working fluid. The gate fluid, passing through the seals, enters the lower cavity of the tank 21, where it is cooled using the refrigerator 22, through which the working fluid is pumped, drained from the discharge chamber of the discharge disk through the pipe 33.

To maintain the necessary pressure of the coolant through the refrigerator 22, a throttle is installed on the pipe 31, which creates resistance to a note of fluid from the drain chamber 11 in the pump inlet 5.

The pressure of the gate fluid in the circulation circuit 20 should be higher than the pressure of the working fluid. This is ensured, firstly, by the assembly of the upper compartment 23 of the tank with an inlet pipe and, secondly, by means of a load 29, which creates the necessary excess pressure on the liquid in the lower compartment 24 of the tank through the membrane 25.

Thus, replacing existing stuffing box seals with maintenance-free long-life mechanical seals can increase the reliability of the pump, eliminate leakage of pumped formation water into the environment, can solve environmental problems and reduce operating costs.

The system for ensuring the circulation of the gate fluid using guaranteed constant pressure over the working fluid with the help of the load does not require monitoring and regulation devices, simplifies and increases the reliability of its operation.

Claims (2)

1. A multistage centrifugal pump containing an inlet and an outlet cover, a housing with inlet and outlet nozzles sandwiched between them by means of ties, made of several sections, a drive shaft passing through the housing with impellers installed one in each section, an unloading disk on the outlet side lids with the formation of a drain chamber and end seals of the end type, connected to the circulation circuit of the shutter fluid, including a tank with a built-in refrigerator, characterized in that the cavity the tank is divided into upper and lower compartments with the help of a membrane mounted above the refrigerator, the circulation circuit of the gate fluid is connected to the lower compartment of the tank, and in the upper compartment, in communication with the pump inlet pipe, a coaxial rod is installed, the lower end of which is attached to the membrane, and the upper - brought out and supplied with cargo. 2. The multistage centrifugal pump according to claim 1, characterized in that the inlet and outlet of the refrigerator are in communication with the inlet of the pump, while on the pipeline connecting the inlet of the pump to the inlet of the refrigerator, a throttle is installed, behind which a drain chamber is connected to it.