CN216666596U

CN216666596U - Pressure difference valve of generator sealing oil system

Info

Publication number: CN216666596U
Application number: CN202123200734.9U
Authority: CN
Inventors: 李峰; 高学斌; 张雷; 李兆远; 王硕; 吴家辉
Original assignee: Harbin Hakong Industry Co ltd
Current assignee: Harbin Hakong Industry Co ltd
Priority date: 2021-12-17
Filing date: 2021-12-17
Publication date: 2022-06-03
Anticipated expiration: 2031-12-17

Abstract

The utility model discloses a pressure difference valve of a generator sealing oil system, and belongs to the technical field of hydrogen-cooled turbine generator sealing oil systems. The pressure difference valve of the generator sealing oil system comprises a pressure measuring body and a valve body, wherein the pressure measuring body is arranged above the valve body, and a spring and a corrugated pipe are arranged in the pressure measuring body; be equipped with valve plug, valve rod and disk seat in the valve body, the disk seat is fixed in the valve body, the valve plug is located the disk seat, the valve rod is located the top of valve plug, valve rod and bellows swing joint, be equipped with sky side oil pressure gassing cock, sky side oil signal pipe and hydrogen oil pressure signal pipe on the pressure cell. The pressure difference valve of the generator sealing oil system is reasonable in design, reliable in action, accurate in control and convenient to operate, and completely meets the production requirements; the reliability and the high efficiency of the welding of the middle beam composition of the flat car are greatly improved; meanwhile, the device has good universality, lower manufacturing cost and convenient maintenance.

Description

Pressure difference valve of generator sealing oil system

Technical Field

The utility model relates to a pressure difference valve of a generator sealing oil system, and belongs to the technical field of hydrogen-cooled turbine generator sealing oil systems.

Background

The differential pressure valve is used in the shaft end oil sealing system of hydrogen-cooled turbine generator, tracks the change of hydrogen pressure of the generator, automatically adjusts the oil pressure at the air side, keeps the pressure value 84KPa higher than the hydrogen pressure in the generator, generates a layer of pressure oil seal in the sealing tile, and isolates the hydrogen in the generator from the outside air. The safe and normal operation of the generator set is ensured. Therefore, the differential pressure valve is a very important and indispensable key device in the generator sealing oil system.

The bellows quantity of traditional differential pressure valve all is more than 3 generally, and is in large quantity, and the leakage point also increases thereupon, has increased the leakage probability, has reduced the stability of unit operation work to traditional differential pressure valve exists the regulation time long, adjusts inconveniently, reliability greatly reduced when the unit operation.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defects of the prior art and provides a pressure difference valve of a generator sealing oil system, which reduces the number of corrugated pipes from 3 to 1 compared with the traditional pressure difference valve, greatly reduces leakage points, ensures that a unit runs more safely and reliably, has the characteristics of extremely small friction resistance and time constant, high tracking speed, short regulation time, flexible action, high reliability, extremely convenient pressure difference regulation, permission of regulation during the running of the unit and the like.

The pressure difference valve of the generator sealing oil system comprises a pressure measuring body and a valve body, wherein the pressure measuring body is arranged above the valve body, and a spring and a corrugated pipe are arranged in the pressure measuring body; be equipped with valve plug, valve rod and disk seat in the valve body, the disk seat is fixed in the valve body, the valve plug is located the disk seat, the valve rod is located the top of valve plug, valve rod and bellows swing joint, be equipped with sky side oil pressure gassing cock, sky side oil signal pipe and hydrogen oil pressure signal pipe on the pressure cell.

In an embodiment of the present invention, the valve plug and the valve stem are integrated into a single structure, and are coaxial and made of stainless steel.

In an embodiment of the utility model, an upper cover and a cover body are arranged above the pressure measuring body, the cover body is positioned above the upper cover, and an adjusting screw is arranged between the cover body and the upper cover.

In one embodiment of the utility model, one end of the adjusting screw is connected to the spring, and the spring is used for pressing the corrugated pipe.

In an embodiment of the present invention, a bottom cover is disposed below the valve body, and the bottom cover is connected to the valve body by a bolt.

In one embodiment of the present invention, the number of the valve seats is two, the valve plug penetrates through the two valve seats, oil flowing grooves are uniformly distributed on the valve plug at each valve seat position, and the sealing oil flows through the oil flowing grooves.

In one embodiment of the utility model, a bearing is arranged at the upper end of the valve rod, and the valve rod is movably connected with the corrugated pipe through the bearing.

In one embodiment of the present invention: the bellows divides the pressure measuring body into an upper chamber and a lower chamber, the upper chamber is connected with a hydrogen pressure signal of the generator through a hydrogen oil pressure signal pipe, and the lower chamber is connected with an oil supply pressure signal of a sealed oil air side of the generator through an air side oil signal pipe.

In one embodiment of the utility model, a throttle orifice plate is arranged at the joint of the air side oil signal pipe, a throttle orifice is arranged on the throttle orifice plate, and the aperture of the throttle orifice is 1-3 mm.

In one embodiment of the utility model, the pressure difference valve of the generator sealing oil system is suitable for hydrogen pressure of 0-0.5 MPa, outlet pressure of an air side oil pump of 0.5-1.0 MPa, hydrogen-oil pressure difference regulation range of 40-100 KPa, pressure difference regulation precision of less than or equal to 5KPa, and use flow of less than or equal to 400L/min.

Advantageous effects

1. For the traditional differential pressure valve, the number of the corrugated pipes is reduced from 3 to 1, leakage points are greatly reduced, the unit is safer and more reliable to operate, and the differential pressure valve has the characteristics of extremely small friction resistance and time constant, high tracking speed, short adjusting time, flexible action, high reliability, extremely convenient differential pressure adjustment, allowance for adjustment during the operation of the unit and the like.

2. The sealing oil system is used for sealing hydrogen in the generator, not only is the hydrogen prevented from leaking, but also the generator cannot be fed with oil, so that the sealing oil pressure needs to be kept to be larger than the hydrogen pressure 84Kpa, and the pressure difference valve is used for keeping the hydrogen-oil pressure difference to be the value. The pressure difference valve of the utility model tracks the hydrogen pressure by controlling the magnitude of the recirculation of the air side sealing oil, the hydrogen-oil pressure difference of 84KPa is realized by the spring force of the pressure difference valve, no thermal factors exist, the pressure difference valve is generated by a pure mechanical structure, and the magnitude of the hydrogen-oil pressure difference is changed by adjusting the compression amount of the spring. After the adjusting rod is positioned, the pressure difference valve automatically adjusts the recirculation of the air side sealing oil according to the introduced air side sealing oil pressure and hydrogen pressure signals, so that the air side sealing oil pressure is always higher than the hydrogen pressure of 84 Kpa.

3. The differential pressure valve can enable the differential pressure value between the oil pressure at the air side and the hydrogen pressure to be 84KPa, prevent hydrogen from entering air and ensure long-term stable operation of a unit. Because 2 corrugated pipes of a valve body part which is easy to damage of a conventional differential pressure valve are cancelled, the service life is longer, and the interval of the overhaul period is increased. The valve has high precision and rapid and stable tracking. The interface size may replace a conventional differential pressure valve.

4. The sealing oil flows through the oil flow groove, and the area of the flow passage is changed according to the difference of the relative positions of the valve plug and the valve seat, so that the flow passing through the differential pressure valve is adjusted, and the pressure value is further changed.

5. The valve rod is movably connected with the corrugated pipe, and the end part of the valve rod is provided with the bearing, so that possible internal blockage can be eliminated when the corrugated pipe stretches and retracts to drive the valve plug to move up and down, and the bearing ensures that the valve plug does not generate blockage phenomenon when rotating, and ensures that the valve plug generates free movement in the valve seat.

Drawings

FIG. 1 is a cross-sectional view of a generator seal oil system differential pressure valve of the present invention;

in the figure: 1-cover body, 2-adjusting screw, 3-upper cover, 4-hydrogen oil pressure deflation cock, 5-spring, 6-bellows, 7-pressure measuring body, 8-dead side oil pressure deflation cock, 9-bearing, 10-valve body, 11-bottom cover, 12-valve plug, 13-valve rod, 14-dead side oil signal pipe, 15-hydrogen oil pressure signal pipe, 16-valve seat and 17-oil flowing groove.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. In which like parts are designated by like reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the drawings. The terms "inner" and "outer" are used to refer to directions toward and away from, respectively, the geometric center of a particular component.

Example 1

A pressure difference valve of a generator sealing oil system comprises a pressure measuring body 7 and a valve body 10, wherein the pressure measuring body 7 is arranged above the valve body 10, and a spring 5 and a corrugated pipe 6 are arranged in the pressure measuring body 7; a valve plug 12, a valve rod 13 and a valve seat 16 are arranged in the valve body 10, the valve seat 16 is fixed in the valve body 10, the valve plug 12 is positioned in the valve seat 16, the valve rod 13 is positioned above the valve plug 12, the valve plug 12 and the valve rod 13 are of an integrated structure and made of stainless steel, the surface of the valve plug is subjected to quenching treatment, the surface strength is high, and the valve plug is corrosion-resistant; the upper end of valve rod 13 is equipped with bearing 9, and valve rod 13 passes through bearing 9 and is connected with bellows 6, be equipped with sky side oil pressure gassing cock 8, sky side oil signal pipe 14 and hydrogen oil pressure signal pipe 15 on the pressure cell 7, be equipped with upper cover 3 and cover body 1 above the pressure cell 7, cover body 1 is located the top of upper cover 3, is equipped with adjusting screw 2 between cover body 1 and the upper cover 3, adjusting screw 2's one end with spring 5 is connected.

Further, the valve plug 12 is coaxial with the valve stem 13.

Further, a bottom cover 11 is arranged below the valve body 10, and the bottom cover 11 is connected with the valve body 10 through a bolt.

Furthermore, a throttle orifice plate is arranged at the joint of the air side oil signal pipe 14, a throttle orifice is formed in the throttle orifice plate, and the aperture of the throttle orifice is 1-3 mm.

Further, the number of the valve seats 16 is two, the valve plugs 12 penetrate through the two valve seats 16, oil flowing grooves 17 are uniformly formed in the valve plugs 12 at the positions of the valve seats 16, sealing oil flows through the oil flowing grooves 17, and the flow area is changed according to the difference of the relative positions of the valve plugs 12 and the valve seats 16, so that the flow passing through the differential pressure valve is adjusted, and the pressure value is changed.

Further, valve rod 13 and bellows 6 are swing joint, and bearing 9 is installed to the tip simultaneously, and bellows 6 is flexible like this and can be eliminated inside possible jamming when driving valve plug 12 up-and-down motion, guarantees not to take place the jam phenomenon when bearing 9 makes valve plug 12 rotatory again simultaneously, ensures to take place free motion in disk seat 16.

The working principle of the utility model is as follows: the pressure measuring mechanism of the generator sealing oil system differential pressure valve is composed of a corrugated pipe 6 and a pressure measuring body 7, the corrugated pipe 6 is connected with a valve plug 12 through a valve rod 13, and the valve plug 12 moves synchronously when the corrugated pipe 6 stretches out and draws back, so that the opening degree of the differential pressure valve is controlled, and pressure is further controlled. The corrugated pipe 6 divides the pressure measuring body 7 into an upper chamber and a lower chamber, the upper chamber is connected with a generator hydrogen pressure signal through a hydrogen oil pressure signal pipe 15, and the lower chamber is connected with a generator sealing oil air side oil supply pressure signal through an air side oil signal pipe 14. And a spring 5 is arranged above the corrugated pipe 6, the spring 5 is used for pressurizing the corrugated pipe 6, and when the corrugated pipe 6 stretches, the difference value between the upper chamber pressure and the lower chamber pressure is equal to the sum of the compression force of the spring 5 and the gravity of the valve plug 12.

In normal working hours, the oil pressure of the air side sealing oil acts on the upper part of the corrugated pipe 6, the hydrogen pressure acts on the lower part of the corrugated pipe 6, only when the pressure difference between the upper part and the lower part of the corrugated pipe 6 is 84KPa, the corrugated pipe 6 stops moving and is located at a certain specific position, so that the difference value between the air side oil pressure and the hydrogen pressure is controlled, and the hydrogen pressure is constant, and the air side oil pressure changes along with the change.

The generator sealing oil system differential pressure valve is arranged on a side of a sealing oil side oil pump, namely is connected with an inlet and an outlet of the side oil pump, and plays a role in bypass pressure regulation.

When the hydrogen pressure rises, the pressure acting on the upper part of the corrugated pipe 6 is increased, the valve rod 13 moves downwards to drive the valve plug 12 to move downwards, the opening areas of the valve plug 12 and the valve seat 16 are reduced, the flow is reduced, namely, the bypass flow is reduced, the oil supply quantity on the air side is increased, the pressure is increased, and when the hydrogen-oil pressure difference reaches 85KPa again, the valve plug 12 stops moving after a new balance point is established again. On the contrary, when the hydrogen pressure decreases, the pressure acting on the upper portion of the bellows 6 decreases, the valve rod 13 moves upward, the valve plug 12 is driven to move upward, the opening area between the valve plug 12 and the valve seat 16 increases, the flow rate increases, that is, the bypass flow rate increases, the oil supply amount on the air side decreases, the pressure decreases, and when the hydrogen pressure difference reaches 85KPa again, the valve plug 12 stops moving after establishing a new balance point again.

Further, the pressure difference valve of the generator sealing oil system is suitable for hydrogen pressure of 0-0.5 MPa, outlet pressure of an air side oil pump of 0.5-1.0 MPa, hydrogen-oil pressure difference adjusting range of 40-100 KPa, pressure difference adjusting precision of less than or equal to 5KPa, and maximum using flow of 400L/min.

Further, the pressure difference valve of the generator sealing oil system is suitable for a conventional 300 MW-600 MW hydrogen cooling generator sealing oil system.

The bellows 6 moves when the upper chamber of the pressure measuring body 7, namely the hydrogen pressure, changes, and simultaneously drives the valve plug 12 to move, so that the position of the valve plug 12 changes, the flow of the air side oil changes, the pressure of the air side oil changes, and the air side oil is fed back to the lower chamber of the bellows 6 through the air side oil signal pipe 14, so that the bellows 6 is prevented from further changing until the pressure difference between the air side and the hydrogen pressure of the two chambers of the bellows 6 reaches a set value at a certain position again. The bellows 6 is made of stainless steel, the bellows 6 is combined with the spring 5 and is an adjusting component for realizing constant pressure difference of the pressure difference valve, and when the pressure of the system hydrogen changes, the bellows can push the valve plug 12 to move, so that the pressure difference of the system hydrogen and oil reaches the set pressure difference value again. When the pressure difference value is required to be adjusted during system debugging, the cover body 1 can be opened, the adjusting screw 2 is rotated, the compression amount of the spring 5 is changed, the pressure difference value is changed, the spring 6 is compressed, and the pressure difference value is increased.

The use process of the utility model is as follows: the generator seal oil system differential pressure valve is installed on a side oil pump bypass of a generator seal oil supply device, when the differential pressure valve is installed, an arrow → is marked on a valve body 10 of the differential pressure valve, the flow direction of a medium in the valve body 10 is indicated, as shown in fig. 1, the medium flows from the left side to the right side of the valve body 10, when the valve body 10 is installed, a valve needs to be installed strictly according to the mark, the differential pressure valve is provided with two signal pipe interfaces, a hydrogen oil pressure signal pipe 15 is connected with a hydrogen pressure signal, and an empty oil signal pipe is connected with a seal oil empty side pressure signal.

Because the pressure difference valve is in a completely closed state when the initial hydrogen pressure of the pressure difference valve is not signaled, when the pump is started for the first time, the system can generate an impact pressure instantly. Before starting, the pump bypass manual valve is opened, and after the system is stabilized, the bypass valve is gradually closed. If the system is started or in the running process, the periodic vibration of the system oil pressure occurs, the signal pipe joints at two positions of the differential pressure valve are slowly loosened, the hydrogen oil pressure and the idle side oil pressure signal pipeline of the differential pressure valve are exhausted, about 2 liters of hydrogen is exhausted, the signal pipe joints of the differential pressure valve are screwed under the condition that no gas is exhausted, if the phenomenon still occurs, the instrument valve on the idle side oil pressure signal pipeline of the differential pressure valve is immediately and gradually closed, the differential pressure valve is protected from being damaged, and after the system oil pressure is stable, the instrument valve is gradually opened as required. The closing and opening process time of the instrument valve is based on the disappearance of the periodic vibration of the oil pressure. The instrument valve should be opened immediately after disappearance. The opening degree of the instrument valve is that the instrument valve is opened reversely and rotates for 1-2 circles after the handle is closed. If the system is vibrated frequently, the instrument valve is opened for 1/4-1/2 circles, and if the opening degree cannot be accurately controlled, a throttle orifice plate needs to be added at the interface of an oil pressure signal pipe of the differential pressure valve. Closely paying attention to the numerical value of the hydrogen-oil pressure difference, if the pressure difference value is higher, the cover body 1 at the upper part of the pressure difference valve is removed, the adjusting screw rod 2 is rotated, the method is to screw downwards, the hydrogen-oil pressure difference can be increased, and otherwise, the hydrogen-oil pressure difference can be reduced.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the utility model can be made, and equivalents may be substituted for elements thereof without departing from the scope of the utility model.

Claims

1. The utility model provides a generator seal oil system differential pressure valve which characterized in that: the pressure measuring device comprises a pressure measuring body (7) and a valve body (10), wherein the pressure measuring body (7) is arranged above the valve body (10), and a spring (5) and a corrugated pipe (6) are arranged in the pressure measuring body (7); be equipped with valve plug (12), valve rod (13) and disk seat (16) in valve body (10), disk seat (16) are fixed in valve body (10), valve plug (12) are located disk seat (16), valve rod (13) are located the top of valve plug (12), valve rod (13) and bellows (6) swing joint, be equipped with air side oil pressure gassing cock (8), air side oil signal pipe (14) and hydrogen oil pressure signal pipe (15) on pressure cell (7).

2. The generator seal oil system differential pressure valve of claim 1, wherein: the valve plug (12) and the valve rod (13) are of an integrated structure, coaxial and made of stainless steel.

3. The generator seal oil system differential pressure valve of claim 2, wherein: an upper cover (3) and a cover body (1) are arranged above the pressure measuring body (7), the cover body (1) is positioned above the upper cover (3), and an adjusting screw (2) is arranged between the cover body (1) and the upper cover (3).

4. The generator seal oil system differential pressure valve of claim 3, wherein: one end of the adjusting screw (2) is connected with the spring (5), and the spring (5) is used for pressing the corrugated pipe (6).

5. The generator seal oil system differential pressure valve of claim 4, wherein: a bottom cover (11) is arranged below the valve body (10), and the bottom cover (11) is connected with the valve body (10) through bolts.

6. The generator seal oil system differential pressure valve of claim 5, wherein: the number of the valve seats (16) is two, the valve plugs (12) penetrate through the two valve seats (16), oil flowing grooves (17) are uniformly formed in the valve plugs (12) at the positions of the valve seats (16), and sealing oil flows through the oil flowing grooves (17).

7. The generator seal oil system differential pressure valve of claim 6, wherein: the upper end of the valve rod (13) is provided with a bearing (9), and the valve rod (13) is movably connected with the corrugated pipe (6) through the bearing (9).

8. The generator seal oil system differential pressure valve of claim 7, wherein: bellows (6) divide into two upper and lower cavities with pressure cell (7), and the upper chamber links to each other through hydrogen oil pressure signal pipe (15) and generator hydrogen pressure signal, and the lower cavity links to each other through air side oil signal pipe (14) and generator sealing oil air side fuel feeding pressure signal.

9. The generator seal oil system differential pressure valve of claim 8, wherein: and a throttling orifice plate is arranged at the joint of the air side oil signal pipe (14), a throttling orifice is formed in the throttling orifice plate, and the aperture of the throttling orifice is 1-3 mm.

10. The generator seal oil system differential pressure valve according to any one of claims 1 to 9, wherein: the pressure difference valve of the generator sealing oil system is suitable for hydrogen pressure of 0-0.5 MPa, outlet pressure of an air side oil pump of 0.5-1.0 MPa, hydrogen-oil pressure difference adjusting range of 40-100 KPa, pressure difference adjusting accuracy of less than or equal to 5KPa, and using flow of less than or equal to 400L/min.