CN219570399U

CN219570399U - Front-mounted pump for peak shaving of power plant

Info

Publication number: CN219570399U
Application number: CN202320288543.2U
Authority: CN
Inventors: 王翚; 沈昕; 孙铭泽
Original assignee: Wenergy Hefei Power Generation Co ltd
Current assignee: Wenergy Hefei Power Generation Co ltd
Priority date: 2023-02-17
Filing date: 2023-02-17
Publication date: 2023-08-22
Anticipated expiration: 2033-02-17

Abstract

The utility model belongs to the technical field of energy conservation and consumption reduction of power plant generator sets, and particularly relates to a front pump for peak shaving of a power plant, which comprises a pump body motor shaft, an impeller shaft, and a permanent magnet coupler for connecting the motor shaft and the impeller shaft, wherein the permanent magnet coupler at least comprises: the magnetic rotor back plate, and a first magnet and a second magnet which are arranged in the magnetic rotor back plate, wherein the first magnet is fixedly arranged at the shaft end of the motor shaft, and the second magnet is arranged at the shaft end of the impeller shaft through a spacer; the pre-pump with the permanent magnet coupling solves the problem that the pre-pump in the prior art does not have the capability of automatically reducing the rotating speed to match with the output of the steam-driven water supply pump, effectively solves the problem that the steam pump recirculation adjusting door is frequently opened in the deep peak-shaving process, can greatly reduce the energy consumption of the pre-pump and the steam-driven water supply pump, improves the safety of a water supply system and prolongs the service life of equipment.

Description

Front-mounted pump for peak shaving of power plant

Technical Field

The utility model belongs to the technical field of energy conservation and consumption reduction of power plant generator sets, and particularly relates to a pre-pump for peak shaving of a power plant.

Background

When the power grid further requires the thermal power generating unit to carry out deep peak shaving, the generating load of the unit is reduced to below 30% of the rated load, and the auxiliary equipment of the steam turbine is required to operate under the working condition of being far away from the design value, so that the operating environment of the equipment is poor, and the energy consumption of the auxiliary equipment is increased.

For the current unit adopting the different axial arrangement of the front-end pump and the steam feed pump, the problems of increased energy consumption and damaged operation safety can be brought. If the front-end pump is coaxial with the steam-driven water supply pump, when the load is reduced, the rotating speed of the steam-driven water supply pump is reduced, so that the rotating speed of the front-end pump is driven to be reduced, the flow and the lift of the front-end pump are reduced, the power consumption is reduced, and the radial and axial thrust of the rotating shaft of the front-end pump is reduced, so that the operation safety of the front-end pump is ensured. The front pumps with different shafts are driven by separate motors, the water feed pump is driven by a small steam turbine, the rotating speed of the water feed pump is reduced along with the reduction of the load of the unit, and the flow and the lift are also reduced along with the reduction of the load of the unit; however, the speed of the front-end pump is difficult to be reduced when the load is reduced due to the adoption of the constant-speed motor, the power of the front-end pump is not greatly changed, the flow is reduced, the lift is increased, the radial thrust and the axial thrust of the rotating shaft of the front-end pump are greatly increased, and the operation safety and the operation service life of the front-end pump are influenced.

In addition, when the unit is in deep peak regulation operation, the front-end pump cannot automatically reduce the rotating speed to be matched with the output of the steam-driven water supply pump, and the water supply recycling adjustment door is opened to adjust, so that energy loss and waste are caused, and meanwhile, the reliability of the water supply recycling adjustment door is reduced.

Disclosure of Invention

The utility model aims to provide a pre-pump for peak shaving of a power plant, so as to solve the problem that the safe operation life of the pre-pump and a water supply recycling adjusting door of a power plant generator set provided in the background art is easily influenced in the deep peak shaving process.

The utility model realizes the above purpose through the following technical scheme:

the utility model provides a pre-pump for peak shaving of power plant, includes pump body motor shaft, impeller shaft, still includes the hookup the motor shaft with the permanent magnet coupling of impeller shaft, the permanent magnet coupling includes at least:

the magnetic rotor back plate, and a first magnet and a second magnet which are arranged in the magnetic rotor back plate, wherein the first magnet is fixedly arranged at the shaft end of the motor shaft, the second magnet is arranged at the shaft end of the impeller shaft through a spacer, the first magnet and the second magnet are arranged in parallel, a gap is reserved between the first magnet and the second magnet, and the spacer is positioned in the gap;

the translation mechanism and the actuator thereof are used for electrically controlling and driving the spacer to move so as to adjust the gap between the first magnet and the second magnet.

As a further optimization scheme of the utility model, the translation mechanism comprises a sleeve arranged at the side end of the magnetic rotor backboard, a screw shaft and a screw nut which are arranged in the sleeve and are in threaded connection, the screw shaft is rigidly connected with the isolating piece through a connecting shaft, and the screw nut and the actuator are driven to rotate.

As a further optimized scheme of the utility model, the actuator is specifically a gear meshed with the outer end face of the screw nut for transmission.

As a further optimization scheme of the utility model, the impeller shaft is rotationally and hermetically connected with the magnetic rotor back plate and the sleeve through flange nuts.

As a further optimization scheme of the utility model, the isolation piece is specifically a semi-open frame piece, and the semi-open surface faces to the joint of the impeller shaft and the magnetic rotor backboard.

As a further optimization scheme of the utility model, the translation mechanism further comprises an annular limiting plate for supporting the isolating piece to rotate, and the annular limiting plate is arranged on the magnetic rotor backboard.

The utility model has the beneficial effects that:

(1) The pre-pump with the permanent magnet coupling solves the problem that the pre-pump in the prior art does not have the capability of automatically reducing the rotating speed to match the output of the steam-driven water supply pump, effectively solves the problem that a steam pump recirculation adjusting door is frequently opened in the deep peak-shaving process, can greatly reduce the energy consumption of the pre-pump and the steam-driven water supply pump, improves the safety of a water supply system and prolongs the service life of equipment;

(2) The spacer for realizing the adjustment of the gaps between the magnets is particularly a semi-open frame, and the semi-open surface faces the joint of the impeller shaft and the magnetic rotor back plate, so that the non-contact connection is realized, the gas and the heat at the joint of the impeller shaft and the magnetic rotor back plate can be prevented from flowing out and being transferred to the motor shaft as little as possible, the effect of isolating the heat and the air flow is achieved, and the sealing effect is improved.

Drawings

FIG. 1 is a block diagram of a conventional system of a prior art power plant genset;

FIG. 2 is a schematic illustration of a pump coupling configuration in accordance with the present utility model;

fig. 3 is a schematic view of the structure of the separator in the present utility model.

In the figure: 1. a deaerator; 2. a front pump inlet shutoff valve; 3. a pre-pump; 4. a feed pump turbine; 5. a pneumatic feed pump; 6. a load; 31. a magnetic rotor back plate; 311. a motor shaft; 312. a first magnet; 313. a second magnet; 314. a spacer; 315. an annular limiting plate; 32. a sleeve; 321. an impeller shaft; 322. a screw shaft; 323. a screw nut; 324. an actuator; 33. a flange nut; 34. and a connecting shaft.

Detailed Description

The present utility model will be described in further detail with reference to the accompanying drawings, wherein it is to be understood that the following detailed description is for the purpose of further illustrating the utility model only and is not to be construed as limiting the scope of the utility model, as various insubstantial modifications and adaptations of the utility model to those skilled in the art can be made in light of the foregoing disclosure.

Example 1

As shown in fig. 1, in the prior art, water is deoxidized and heated in a deaerator 1, enters a pre-pump 3 through a pre-pump inlet stop valve 2, is pressurized in the pre-pump 3 and then enters a steam-driven water feed pump 5, the steam-driven water feed pump 5 is driven by a water feed pump turbine 4, and after being further pressurized in the steam-driven water feed pump 5, the water feed is collected in a load 6, wherein the load 6 in the prior art can be a boiler; whereas the backing pump 3 is driven by a constant speed motor, the backing pump 3 in this embodiment is preferably an adjustable speed backing pump, and the preferred scheme is as follows:

referring to fig. 2-3, the utility model provides a pre-pump for peak shaving of a power plant, which comprises a pump body motor shaft 311, an impeller shaft 321, and a permanent magnet coupling connecting the motor shaft 311 and the impeller shaft 321, wherein the permanent magnet coupling at least comprises:

the magnetic rotor backboard 31, and the first magnet 312 and the second magnet 313 arranged in the magnetic rotor backboard 31 are sealed frames, the first magnet 312 is fixedly arranged at the shaft end of the motor shaft 311, the second magnet 313 is arranged at the shaft end of the impeller shaft 321 through the spacer 314, the first magnet 312 and the second magnet 313 are arranged in parallel, a gap is reserved between the first magnet and the second magnet, and the spacer 314 is positioned in the gap;

the translation mechanism and its actuator 324 are used to electrically drive the movement of the spacer 314 to adjust the gap size between the first magnet 312 and the second magnet 313.

The utility model replaces the front-end pump coupler with permanent magnet to transfer torque, and is arranged between the motor and the impeller shaft, and the actuator 324 is arranged to automatically adjust the distance between the permanent magnets in the coupler, thereby achieving the rotation speed control, and when the translation mechanism is electrically controlled, the remote transmission DCS can coordinate and control the rotation speed of the front-end pump according to the flow rate and the inlet pressure of the pneumatic water supply pump.

The translation mechanism in this embodiment includes a sleeve 32 disposed at a side end of the magnetic rotor back plate 31, a screw shaft 322 and a screw nut 323 disposed in the sleeve 32 and in threaded connection, where the screw shaft 322 is rigidly connected to the spacer 314 by a connecting shaft 34, and the screw nut 323 is driven to rotate by an actuator 324; the actuator 324 is specifically a gear meshed with the outer end surface of the lead screw nut 323 for transmission.

In this embodiment, the lead screw nut 323 is specifically connected in the sleeve 32 in an axially fixed connection and radially movably connected manner, so that the lead screw nut 323 can keep rotating along with the actuator 324.

In the embodiment, the translation mechanism can be specifically controlled manually, and when the rotation speed of the front-end pump needs to be coordinated in time in the deep peak regulation process of the power plant, the manual control is that a worker rotates a gear manually to enable a screw nut 323 to rotate, and drives a screw shaft 322 in threaded connection with the screw nut 323 to move so as to drive a spacer 314 to move, so that the gap size between the magnet I312 and the magnet II 313 is adjusted; the control mode can also be an electric control mode, and the adjustment can be realized by installing a motor to drive the gear to rotate so as to drive the screw nut 323 to rotate.

In this embodiment, the impeller shaft 321 is rotationally and hermetically connected with the magnetic rotor back plate 31 and the sleeve 32 through the flange nut 33, specifically, the spline flange nut is rotationally and hermetically connected, and the spline connection realizes a connection mode of axially movable connection and radially fixed connection, so that the screw shaft 322 can rotate along with the impeller shaft 321 and simultaneously has an axial movement interval, and a precondition is provided for adjusting the gap between the first magnet 312 and the second magnet 313.

In order to realize non-contact connection between the impeller shaft 321 and the motor shaft 311, the spacer 314 is specifically a semi-open frame, and the semi-open surface faces the connection position of the impeller shaft 321 and the magnetic rotor back plate 31, so that the design not only realizes non-contact connection, but also can prevent the gas and heat at the connection position of the impeller shaft 321 and the magnetic rotor back plate 31 from being transferred to the motor shaft 311 as little as possible, plays a role in isolating heat and air flow, and improves the sealing effect.

The translation mechanism in this embodiment further includes an annular limiting plate 315 for supporting the rotation of the spacer 314, where the annular limiting plate 315 is disposed on the magnetic rotor back plate 31, so as to further ensure that the spacer 314 does not separate when rotating with the impeller shaft 321, and improve the rigidity.

The pre-pump with the permanent magnet coupling solves the problem that the pre-pump in the prior art does not have the capability of automatically reducing the rotating speed to match with the output of the steam-driven water supply pump, effectively solves the problem that the steam pump recirculation adjusting door is frequently opened in the deep peak-shaving process, can greatly reduce the energy consumption of the pre-pump and the steam-driven water supply pump, improves the safety of a water supply system and prolongs the service life of equipment.

The foregoing examples illustrate only a few embodiments of the utility model and are described in detail herein without thereby limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model.

Claims

1. The utility model provides a pre-pump for peak shaving of power plant, includes pump body motor shaft (311), impeller shaft (321), its characterized in that: also included is a permanent magnet coupling the motor shaft (311) and the impeller shaft (321), the permanent magnet coupling comprising at least:

the magnetic rotor comprises a magnetic rotor backboard (31), a first magnet (312) and a second magnet (313) which are arranged in the magnetic rotor backboard, wherein the first magnet (312) is fixedly arranged at the shaft end of the motor shaft (311), the second magnet (313) is arranged at the shaft end of the impeller shaft (321) through a spacer (314), the first magnet (312) and the second magnet (313) are arranged in parallel, a gap is reserved between the first magnet and the second magnet, and the spacer (314) is arranged in the gap;

and the translation mechanism and an actuator (324) thereof are used for electrically driving the spacer (314) to move so as to adjust the gap size between the first magnet (312) and the second magnet (313).

2. A pre-pump for peak shaving in a power plant as set forth in claim 1, wherein: the translation mechanism comprises a sleeve (32) arranged at the side end of the magnetic rotor backboard (31), a screw rod shaft (322) and a screw rod nut (323) which are arranged in the sleeve (32) and in threaded connection, the screw rod shaft (322) is rigidly connected with the isolating piece (314) through a connecting shaft (34), and the screw rod nut (323) and the actuator (324) are driven to rotate.

3. A pre-pump for peak shaving in a power plant as set forth in claim 2, wherein: the actuator (324) is specifically a gear meshed with the outer end face of the screw nut (323) for transmission.

4. A pre-pump for peak shaving in a power plant as set forth in claim 2, wherein: the impeller shaft (321) is rotationally and hermetically connected with the magnetic rotor back plate (31) and the sleeve (32) through flange nuts (33).

5. A pre-pump for peak shaving in a power plant as set forth in claim 2, wherein: the spacer (314) is in particular a semi-open frame, and the semi-open face is directed towards the junction of the impeller shaft (321) and the magnetic rotor back plate (31).

6. A pre-pump for peak shaving in a power plant as set forth in claim 2, wherein: the translation mechanism further comprises an annular limiting plate (315) for supporting the isolating piece (314) to rotate, and the annular limiting plate (315) is arranged on the magnetic rotor backboard (31).