CN108412776B

CN108412776B - Multistage deep sea mixed transportation pump adopting shaft sleeve structure

Info

Publication number: CN108412776B
Application number: CN201810073296.8A
Authority: CN
Inventors: 郭鹏程; 罗兴锜; 孙帅辉; 张乐福; 宋宇航; 李晨昊; 闫思娜
Original assignee: Xian University of Technology
Current assignee: Xian University of Technology
Priority date: 2018-01-25
Filing date: 2018-01-25
Publication date: 2020-04-21
Anticipated expiration: 2038-01-25
Also published as: CN108412776A

Abstract

The invention discloses a multistage deep sea mixed transportation pump adopting a shaft sleeve structure, which comprises a pump shell, wherein an inlet pump cover and an outlet pump cover are respectively and fixedly arranged at two ends of the pump shell, an outlet connecting pipe is fixedly connected at the other end of the outlet pump cover, an outlet bearing seat is coaxially arranged on the outlet pump cover, an inlet connecting pipe, a bearing box and a motor are sequentially and fixedly connected at the other end of the inlet pump cover, an inlet bearing seat is coaxially arranged on the inlet pump cover, a bearing box shaft is arranged in the bearing box, one end of the bearing box shaft, far away from the motor, extends into the inlet connecting pipe, a pump shaft sleeved with the shaft sleeve is arranged in the pump shell, one end of the pump shaft extends into the inlet connecting pipe and is connected with the bearing box shaft, the other end of the pump shaft is positioned in the outlet bearing seat, a plurality of static diffusers are sequentially and uniformly sleeved on, the pump shaft has high operation efficiency and long service life under the working condition of high gas content.

Description

Multistage deep sea mixed transportation pump adopting shaft sleeve structure

Technical Field

The invention belongs to the technical field of fluid machinery and engineering equipment, and particularly relates to a multistage deep sea mixed delivery pump adopting a shaft sleeve structure.

Background

With the rapid development of economy and industry of all countries in the world, the demand of mineral resources such as oil, gas and the like is increased day by day, while the mineral resources on land are reduced day by day, and the deep sea is used as the last undeveloped area in the world, so that scientists in all countries in the world are disputed and researched due to the abundant mineral resource.

The deep sea oil and gas mining and transportation technology researches how to collect and transport abundant mineral resources such as oil, gas and the like accumulated on the seabed to the sea surface, and a ore lifting technology for lifting the oil and gas resources from the seabed to the sea surface is one of core technologies of the deep sea oil and gas mining and transportation technology, namely a multiphase mixed transportation pump. Mineral resources such as oil gas and the like are distributed on the seabed of thousands of meters, the mining difficulty is high, the requirement on the conveying technology is high, the deep sea mining and conveying system also bears the action of ocean dynamic environments such as ocean currents, wind waves and seawater pressure in the operation process, the operation environment is very severe, and higher requirements are provided for the deep sea mining and conveying technology.

The multiphase pump is divided into a turbine multiphase pump and a volumetric multiphase pump according to the working principle. In many multiphase mixed transportation pumps, although a double-screw multiphase mixed transportation pump and a spiral axial flow multiphase mixed transportation pump are mostly applied in production practice at present, a multistage centrifugal multiphase mixed transportation pump has higher lift than a single-stage centrifugal pump and has larger flow than a piston pump, a diaphragm pump, a screw pump and the like, and the multistage centrifugal pump has the advantages of safe and stable operation, low noise, long service life, convenience in installation and maintenance and the like, and is widely applied to multiple fields of petrochemical industry, electric power, urban water supply and the like.

The multistage centrifugal pump consists of several rotating wheels and fixed guide vane diffusers, and is one kind of no-rod oil pumping unit capable of lifting petroleum with great displacement. But the operation condition of the system is poor under the working condition of high gas content, so that the system is less applied to the undersea mixed transportation system; meanwhile, for the scheme of the long shaft sliding bearing of the multistage pump at present, the arrangement mode that the main shaft is in direct contact with the sliding bearing on the diffuser is mostly adopted, because the deep sea multistage pump is mainly applied to the petroleum transportation engineering in deep sea, impurities such as water, petroleum and sand are contained in transported media, if the arrangement mode that the main shaft is in direct contact with the sliding bearing is adopted, the media are in direct contact with the main shaft, the surface abrasion of the main shaft is caused, in the work, the rotating speed of the main shaft is high, the generated friction force is large, the service life of the main shaft is reduced in the reciprocating work, and the long-term view is not favorable for saving the manufacturing cost.

Disclosure of Invention

The invention aims to provide a multistage deep sea mixed transportation pump adopting a shaft sleeve structure, which has high operation efficiency and long service life of a pump shaft under the working condition of high gas content.

The technical scheme adopted by the invention is as follows: a multi-stage deep sea mixed transportation pump adopting a shaft sleeve structure comprises a cylindrical pump shell, wherein an inlet pump cover and an outlet pump cover are fixedly arranged at two ends of the pump shell respectively, an outlet connecting pipe is fixedly connected at the other end of the outlet pump cover, an outlet bearing seat for communicating the pump shell with the outlet connecting pipe is coaxially arranged on the outlet pump cover, an inlet connecting pipe, a bearing box and a motor are fixedly connected at the other end of the inlet pump cover in sequence, an inlet bearing seat for communicating the pump shell with the inlet connecting pipe is coaxially arranged on the inlet pump cover, a bearing box shaft coaxially and fixedly connected with an output shaft of the motor is arranged in the bearing box, one end of the bearing box shaft, far away from the motor, extends into the inlet connecting pipe, a pump shaft is arranged in the pump shell, one end of the pump shaft penetrates through the inlet bearing seat and extends, a plurality of stages of static diffusers are sequentially and uniformly sleeved on the pump shaft between the inlet pump cover and the outlet pump cover along the axial direction, and one end of each diffuser, which is close to the inlet pump cover, is provided with a closed impeller fixedly sleeved with the pump shaft in a matching manner;

connecting sleeves sleeved on the pump shaft are arranged between the outlet bearing seat and the final-stage diffuser and between each stage of impeller and the previous-stage diffuser, outer bushings are fixed at the centers of the plurality of stages of diffusers, and inner bushings in sliding fit with the outer bushings are fixed at positions, close to the diffusers, on the pump shaft.

The present invention is also characterized in that,

the plurality of stages of diffusers are clamped on the inner wall of the pump shell and are connected with the pump shaft in a sliding mode, the diffusers at two ends are respectively abutted to the inlet pump cover and the outlet pump cover, and two adjacent diffusers are mutually clamped.

An inlet fluid director is arranged between the inlet bearing seat and the wheel cover of the first-stage impeller, the other end of the wheel cover of the first-stage impeller is connected to the first-stage diffuser, an outlet fluid director is arranged between the last-stage diffuser and the outlet bearing seat, and the wheel discs of the plurality of stages of impellers are fixedly sleeved with the pump shaft.

A support bushing is arranged at the position, extending out of the bearing box, of the bearing box shaft, an inlet bearing bushing is arranged at the position, penetrating through the inlet bearing seat, of the pump shaft, and an outlet bearing bushing is arranged at the position, penetrating through the outlet bearing seat, of the pump shaft.

First O-shaped sealing rings are arranged between the inlet pump cover and the inlet connecting pipe and between the outlet pump cover and the outlet connecting pipe; second O-shaped sealing rings are arranged between the plurality of stages of diffusers and the pump shell.

Spring retainer rings are arranged at one end of the pump shaft, which is positioned in the outlet bearing seat, and at one end of the pump shaft, which is positioned in the inlet bearing seat.

And antiwear rings are arranged at one end of the wheel cover of the impeller, which is close to the diffuser matched with the impeller.

The bearing box shaft is sleeved with a pump inlet mechanical seal and a water throwing ring in parallel, and the pump inlet mechanical seal is close to the inlet connecting pipe.

The impeller and diffuser are each provided with 25 stages.

The invention has the beneficial effects that: according to the multistage deep sea mixed delivery pump adopting the shaft sleeve structure, the problem of performance reduction of a centrifugal mixed delivery pump at high gas content is solved to a certain extent by adopting the multistage multiphase mixed delivery pump behind an ultrahigh pressure inlet, and the anti-cavitation capability of a blade is improved; the structural design that the axial force supporting device and the pump body are separately arranged enables comprehensive performance indexes such as the operation stability, the hydraulic efficiency under high gas content and the like of the multiphase pump to be remarkably improved; the inner bushing is driven by the pump shaft to rotate and forms a sliding bearing with an outer bushing on the diffuser, the ultra-long pump shaft can be effectively supported, the pump shaft is prevented from being eccentric, and the inner bushing is combined with the connecting sleeve to prevent a medium from being in direct contact with the surface of the pump shaft.

Drawings

FIG. 1 is a schematic structural diagram of a multistage deep sea mixing pump adopting a shaft sleeve structure according to the invention;

FIG. 2 is a schematic structural diagram of an impeller in the multistage deep sea mixing pump adopting a shaft sleeve structure according to the present invention;

FIG. 3 is a perspective view of an impeller of the multistage deep sea mixing pump using a shaft sleeve structure according to the present invention;

FIG. 4 is a schematic structural diagram of a diffuser in the multistage deep sea mixing pump adopting a shaft sleeve structure according to the invention;

FIG. 5 is a perspective view of a diffuser in the multistage deep sea mixing pump adopting a shaft sleeve structure according to the present invention;

FIG. 6 is a schematic view of a partial structure of an inlet of a multistage deep sea mixing pump using a shaft sleeve structure according to the present invention;

fig. 7 is a partially enlarged view of the multistage deep sea fluid mixing pump of fig. 6 using a sleeve structure according to the present invention.

In the drawing, 1, a pump shell, 2, an inlet pump cover, 3, an outlet pump cover, 4, an outlet connecting pipe, 5, an outlet bearing seat, 6, an inlet connecting pipe, 7, a bearing box, 8, a motor, 9, an inlet bearing seat, 10, a bearing box shaft, 11, a pump shaft, 12, a coupling, 13, a diffuser, 14, an impeller, 15, an inlet fluid director, 16, an outlet fluid director, 17, a support bushing, 18, an inlet bearing bushing, 19, an outlet bearing bushing, 20, a first O-shaped sealing ring, 21, a second O-shaped sealing ring, 22, a spring retainer ring, 23, 24, a pump inlet mechanical seal, 25, a water slinger, 26, a connecting sleeve, 27, an outer bushing and 28, an inner bushing are arranged.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

The invention provides a multistage deep sea mixed transportation pump adopting a shaft sleeve structure, which comprises a cylindrical pump shell 1, wherein an inlet pump cover 2 and an outlet pump cover 3 are respectively and fixedly arranged at two ends of the pump shell 1, an outlet connecting pipe 4 is fixedly connected at the other end of the outlet pump cover 3, an outlet bearing seat 5 for communicating the pump shell 1 with the outlet connecting pipe 4 is coaxially arranged on the outlet pump cover 3, an inlet connecting pipe 6, a bearing box 7 and a motor 8 are sequentially and fixedly connected at the other end of the inlet pump cover 2, an inlet bearing seat 9 for communicating the pump shell 1 with the inlet connecting pipe 6 is coaxially arranged on the inlet pump cover 2, a bearing box shaft 10 coaxially and fixedly connected with an output shaft of the motor 8 is arranged in the bearing box 7, a pump inlet mechanical seal 24 and a water throwing ring 25 are sleeved on the bearing box shaft 10 in parallel, the pump inlet mechanical seal 24 is close to the inlet connecting pipe 6, one end of the bearing box shaft 10 far away from the motor, a pump shaft 11 is arranged in a pump shell 1, one end of the pump shaft 11 penetrates through an inlet bearing seat 9 and extends into an inlet connecting pipe 6 and is connected with a bearing box shaft 10 through a coupling 12, the other end of the pump shaft 11 is positioned in an outlet bearing seat 5, 25-stage static diffusers 13 are sequentially and uniformly sleeved on the pump shaft 11 and positioned between the inlet pump cover 2 and the outlet pump cover 3 along the axial direction, the 25-stage diffusers 13 are clamped on the inner wall of the pump shell 1 and are in sliding connection with the pump shaft 11, diffusers 13 positioned at two ends are respectively abutted against the inlet pump cover 2 and the outlet pump cover 3, two adjacent diffusers 13 are mutually clamped, one end of each diffuser 13 close to the inlet pump cover 2 is provided with a closed impeller 14 fixedly sleeved with the pump shaft 11 in a matching way, and connecting sleeves 26 sleeved on the pump shaft 11 are arranged between the outlet bearing seat 5 and the diffuser 13 and between each stage, an outer bushing 27 is fixed at the center of each of the plurality of stages of diffusers 13, an inner bushing 28 which is in sliding fit with the outer bushing 27 is fixed at a position, close to the diffuser 13, on the pump shaft 11, an anti-wear ring 23 is arranged at one end, close to the diffuser 13 which is matched with the impeller 14, on the shroud of the impeller 14, an inlet fluid director 15 is arranged between the inlet bearing seat 9 and the shroud of the first-stage impeller 14, the other end of the shroud of the first-stage impeller 14 is connected to the first-stage diffuser 13, an outlet fluid director 16 is arranged between the last-stage diffuser 13 and the outlet bearing seat 5, and the wheel disc of the 25-stage impeller 14.

A support bush 17 is arranged at the position where the bearing box shaft 10 extends out of the bearing box 7, an inlet bearing bush 18 is arranged at the position where the pump shaft 11 passes through the inlet bearing block 9, and an outlet bearing bush 19 is arranged at the position where the pump shaft 11 passes through the outlet bearing block 5. First O-shaped sealing rings 20 are arranged between the inlet pump cover 2 and the inlet connecting pipe 6 and between the outlet pump cover 3 and the outlet connecting pipe 4; a second O-ring 21 is arranged between the 25-stage diffuser 13 and the pump casing 1. Spring retainer rings 22 are arranged at one ends of the pump shafts 11 in the outlet bearing seats 5 and the pump shafts 11 in the inlet bearing seats 9.

When the pump works, a liquid medium passes through the inlet bearing seat 9 on the inlet pump cover 2 through the inlet connecting pipe 6 and enters the pump shell 1, then flows through the inlet fluid director 15 and enters the wheel cover of the first-stage impeller 14, under the rotation action of the wheel disc of the impeller 14, the liquid flows into the diffuser 13 along the wheel cover of the impeller 14 in the radial direction, the kinetic energy of the liquid is converted into static pressure energy in the diffuser 13, and the static pressure energy is guided out into the outlet connecting pipe 4 through the outlet fluid director 16 through the outlet bearing seat 5 after sequentially passing through the 25-stage impeller 14 and the diffuser 13. The wheel disc of the impeller 14 and the guide vane of the diffuser 13 of the invention both adopt arc blades, so that the invention can still achieve higher operation efficiency under the working condition of high gas content, and simultaneously higher inlet pressure can also lead the gas phase to obtain certain volume compression in the conveying process without being gathered in a flow passage in a large amount to block the flow passage, thereby improving the operation efficiency of the mixed conveying pump, while the prior multi-stage pump needs two forms of guide vanes, namely a positive guide vane and a negative guide vane, to realize the flowing medium flowing from one stage to the next stage when the flow direction of the medium is changed between the stages, the guide vane designed by the invention realizes the flowing direction change of the fluid in the flow passage through one guide vane diffuser 13 and ensures that the fluid has smaller turbulent flow state when entering the next stage of the rotating wheel, the invention adopts the 25-stage impeller 14 and the diffuser 13 under the condition of ensuring stable flow state, the invention can achieve larger pressurization as far as possible, because the invention is applied to deep sea oil and gas exploitation, the aim is to realize the transportation of the medium from the exploitation port to the sea level directly by a group of multi-stage mixing transportation pumps;

the inner bushing 28 rotates under the driving of the pump shaft 11, and forms a sliding bearing with the outer bushing 27 on the diffuser 13, so that the overlong pump shaft 11 can be effectively supported, the pump shaft 11 is prevented from being eccentric, the inner bushing 28 is combined with the connecting sleeve 26 to prevent a medium from being in direct contact with the surface of the pump shaft 11, and only the inner bushing 28 and the connecting sleeve 26 need to be replaced after being worn, so that the method is economical and convenient compared with the replacement of the overlong pump shaft 11, if a shaft sleeve structure is not adopted, the surface of the pump shaft 11 needs to be treated, the hardness of the pump shaft is improved, and the cost for surface treatment on the whole long pump shaft 11 is high and the difficulty is high; if the shaft sleeve structure is adopted, only surface hardening treatment needs to be carried out on the shaft sleeve, so that the cost and the process difficulty are reduced.

The inlet fluid director 15 and the outlet fluid director 16 enable the flow channels to be smooth without large cavities or bulges, thereby reducing the flow loss and realizing the effect of stable backflow; the arrangement of the antiwear ring 23 enables the wheel disc of the impeller 14 to move towards the pump outlet side under the action of centrifugal force when the wheel disc works, so as to prevent the wheel disc from directly contacting and rubbing with the diffuser 13, reduce friction loss and prolong the service life of the wheel disc; the water slinger 25 is arranged to prevent working medium seeped out from the pump inlet mechanical seal 24 from entering the bearing box 7, and is matched with the pump inlet mechanical seal 24 for protection.

Through the mode, the multistage deep sea mixed transfer pump adopting the shaft sleeve structure meets ultrahigh pressure values in deep sea oil extraction, and the structures and the seals of all parts are designed and arranged according to the pressure bearing capacity of 30 MPa; the multi-stage design is adopted, the lift is high, the efficiency is high, the long-distance conveying is met, the high efficiency is maintained under the condition that the gas content is 30 percent, and the efficiency reaches more than 60 percent; each stage of diffuser 13 is provided with a radial sliding bearing to ensure that the diffuser 13 does not generate radial deflection, and the connecting structure of the diffuser 13 ensures that the diffuser cannot axially move through the compression of two ends; the inner liner 28 in combination with the connection sleeve 26 can prevent direct contact of the medium with the surface of the pump shaft 11, thereby increasing the service life of the pump shaft 11; the pump shaft 11 and the bearing box shaft 10 are connected in the inlet connecting pipe 6 through the coupler 12, the bearing box shaft 10 is sealed through mechanical sealing, axial force is borne by the independent bearing box 7, operation and maintenance are convenient, and stable operation of the multiphase pump is not affected.

Claims

1. A multi-stage deep sea mixed transportation pump adopting a shaft sleeve structure is characterized by comprising a cylindrical pump shell (1), wherein an inlet pump cover (2) and an outlet pump cover (3) are fixedly arranged at two ends of the pump shell (1) respectively, an outlet connecting pipe (4) is fixedly connected at the other end of the outlet pump cover (3), an outlet bearing seat (5) for communicating the pump shell (1) with the outlet connecting pipe (4) is coaxially arranged on the outlet pump cover (3), an inlet connecting pipe (6), a bearing box (7) and a motor (8) are fixedly connected at the other end of the inlet pump cover (2) in sequence, an inlet bearing seat (9) for communicating the pump shell (1) with the inlet connecting pipe (6) is coaxially arranged on the inlet pump cover (2), a bearing box shaft (10) coaxially and fixedly connected with an output shaft of the motor (8) is arranged in the bearing box (7), and one end, far away from the motor (8), of the bearing box shaft (, a pump shaft (11) is arranged in the pump shell (1), one end of the pump shaft (11) penetrates through an inlet bearing seat (9) and extends into an inlet connecting pipe (6) and is connected with a bearing box shaft (10) through a coupler (12), the other end of the pump shaft (11) is positioned in an outlet bearing seat (5), a plurality of stages of static diffusers (13) are sequentially and uniformly sleeved between the inlet pump cover (2) and the outlet pump cover (3) along the axial direction on the pump shaft (11), and one end, close to the inlet pump cover (2), of each diffuser (13) is provided with a closed impeller (14) fixedly sleeved with the pump shaft (11) in a matched mode;

connecting sleeves (26) sleeved on the pump shaft (11) are arranged between the outlet bearing seat (5) and the last-stage diffuser (13) and between each-stage impeller (14) and the last-stage diffuser (13), outer bushings (27) are fixed at the centers of the plurality of stages of diffusers (13), and inner bushings (28) in sliding fit with the outer bushings (27) are fixed at positions, close to the diffusers (13), on the pump shaft (11);

the diffuser (13) of each stage is clamped on the inner wall of the pump shell (1) and is in sliding connection with the pump shaft (11), the diffusers (13) at two ends respectively abut against the inlet pump cover (2) and the outlet pump cover (3), and two adjacent diffusers (13) are mutually clamped;

an inlet fluid director (15) is arranged between the inlet bearing seat (9) and the wheel cover of the first-stage impeller (14), the other end of the wheel cover of the first-stage impeller (14) is connected to the first-stage diffuser (13), an outlet fluid director (16) is arranged between the last-stage diffuser (13) and the outlet bearing seat (5), and wheel discs of the plurality of stages of impellers (14) are fixedly sleeved with the pump shaft (11).

2. The multistage deep sea mixing pump adopting the shaft sleeve structure according to claim 1, wherein a support bush (17) is disposed at a position where the bearing housing shaft (10) extends out of the bearing housing (7), an inlet bearing bush (18) is disposed at a position where the pump shaft (11) passes through the inlet bearing seat (9), and an outlet bearing bush (19) is disposed at a position where the pump shaft (11) passes through the outlet bearing seat (5).

3. The multistage deep sea mixing and transporting pump adopting the shaft sleeve structure as claimed in claim 1, wherein first O-ring seals (20) are respectively arranged between the inlet pump cover (2) and the inlet connecting pipe (6) and between the outlet pump cover (3) and the outlet connecting pipe (4); second O-shaped sealing rings (21) are arranged between the plurality of stages of diffusers (13) and the pump shell (1).

4. The multistage deep sea mixing and transporting pump adopting the shaft sleeve structure as claimed in claim 1, wherein a spring retainer ring (22) is arranged at one end of the pump shaft (11) positioned in the outlet bearing seat (5) and at one end of the pump shaft (11) positioned in the inlet bearing seat (9).

5. The multistage deep sea mixing and transporting pump adopting the shaft sleeve structure as claimed in claim 1, wherein one end of a wheel cover of the impeller (14) close to a diffuser (13) matched with the wheel cover is provided with an anti-wear ring (23).

6. The multistage deep sea multiphase pump adopting the shaft sleeve structure as claimed in claim 1, wherein a pump inlet mechanical seal (24) and a water slinging ring (25) are sleeved on the bearing box shaft (10) in parallel, and the pump inlet mechanical seal (24) is close to the inlet connecting pipe (6).

7. The multistage deep sea multiphase pump using the shaft sleeve structure according to claim 1, wherein the impeller (14) and the diffuser (13) are provided with 25 stages.