CN212203271U

CN212203271U - Bellows balancing spring type pilot valve for steam of nuclear power station

Info

Publication number: CN212203271U
Application number: CN202020702409.9U
Authority: CN
Inventors: 王秋林; 周辰; 顾朝党
Original assignee: SHANGHAI VALVE FACTORY CO Ltd
Current assignee: SHANGHAI VALVE FACTORY CO Ltd
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2020-12-22
Anticipated expiration: 2030-04-30

Abstract

The utility model discloses a bellows balance spring formula pilot valve for nuclear power station steam, including bellows subassembly and piston. The lower valve seat of the pilot valve is arranged at the bottom of the valve body, the lower valve clack is arranged on the lower valve seat, the upper valve seat is arranged at the upper part of the inner cavity of the valve body, the upper valve clack is arranged on the upper valve seat, a push rod guide sleeve with a push rod arranged inside is arranged between the lower valve clack and the upper valve seat, and the push rod is over against the center of the lower valve clack; the upper valve clack is arranged in a valve clack seat of the corrugated pipe assembly, the upper valve clack and the corrugated pipe assembly are arranged in a guide sleeve, and the guide sleeve is arranged at the top of an inner cavity of the valve body; the piston is installed in the tip of valve rod, and the valve rod sets up in bellows subassembly, and the outside of piston is equipped with the piston uide bushing, and the piston uide bushing outside is equipped with a spacer sleeve, and the spacer sleeve is installed on the last plane of uide bushing. The utility model discloses safe and reliable can well adapt to the service environment of nuclear power station.

Description

Bellows balancing spring type pilot valve for steam of nuclear power station

Technical Field

The utility model relates to a bellows balance spring formula pilot valve for nuclear power station steam for nuclear power field.

Background

In the fields of petrochemical industry, thermal power stations and the like, a pilot safety valve is frequently used, a pilot valve of the pilot safety valve is directly emptied (namely no additional back pressure exists at the discharge outlet of the pilot valve), and the pilot safety valve cannot be used in the working condition with additional variable back pressure. The pilot valve is not provided with an adjusting ring adjusting structure and cannot adjust the excess pressure and the opening and closing pressure difference. The pilot valve of the pilot operated safety valve used in the petrochemical industry basin has low service temperature which is generally not more than 200 ℃, and the valve sealing element used in the pilot valve is a rubber O-shaped ring and can not be applied to high-temperature and high-pressure working conditions.

The medium of part of the system of the nuclear power station has radioactivity, the medium is high temperature and high pressure, the medium discharged by the pilot valve cannot be directly discharged, and the discharge port has variable additional backpressure, so that the pilot operated safety valve used in the prior art is difficult to be applied to the use scene of the nuclear power station environment.

SUMMERY OF THE UTILITY MODEL

The utility model aims at overcoming the not enough of prior art, provide a nuclear power station is bellows balance spring pilot valve for steam, it can well adapt to the service environment of nuclear power station, and the reliability is good.

One technical scheme for achieving the above purpose is as follows: a balance spring type guide valve of a corrugated pipe for steam of a nuclear power station comprises a valve body, a valve rod, a valve seat component and a valve clack component, wherein the valve seat component and the valve clack component are arranged in an inner cavity of the valve body;

the valve seat assembly comprises a lower valve seat and an upper valve seat, the valve clack assembly comprises a lower valve clack and an upper valve clack, the lower valve seat is arranged at the bottom of the valve body, the lower valve clack is mounted on the lower valve seat, the upper valve seat is arranged at the upper part of an inner cavity of the valve body, the upper valve clack is mounted on the upper valve seat, a push rod guide sleeve is arranged between the lower valve clack and the upper valve seat, a push rod is mounted in the push rod guide sleeve, and the push rod is opposite to the center;

the bottom of the corrugated pipe assembly is provided with a valve seat, the middle section of the corrugated pipe assembly is of a corrugated pipe structure, the top of the corrugated pipe assembly is provided with a flange, the upper valve clack is arranged in the valve seat, the upper valve clack and the corrugated pipe assembly are arranged in a guide sleeve, and the guide sleeve is arranged at the top of the inner cavity of the valve body;

the piston is installed in the tip of valve rod, the valve rod set up in the bellows subassembly, the outside of piston is equipped with the piston uide bushing, the lower surface of this piston uide bushing with the ring flange contact of bellows subassembly, the piston uide bushing outside is equipped with a spacer sleeve, the spacer sleeve is installed on the upper plane of uide bushing.

Furthermore, the bottom end of the push rod is of a round head structure, and a round groove matched with the round head structure is formed in the top surface of the lower valve clack.

Furthermore, an adjusting ring is sleeved on the outer side of the guide sleeve.

Furthermore, the valve body is provided with an adjusting hole leading to the adjusting ring, and the adjusting ring is fixed by an adjusting ring support pin.

Furthermore, a limiting sleeve is sleeved outside the valve rod, the limiting sleeve is arranged above the piston guide sleeve, a limiting nut is sleeved outside the valve rod, and the limiting nut is located inside the limiting sleeve.

The utility model discloses a bellows balance spring formula pilot valve for nuclear power station steam has following advantage:

1) the utility model discloses a measure of the double balance backpressure of bellows and piston makes setting pressure of valve not receive the influence of backpressure. Meanwhile, the corrugated pipe plays a role in isolating the medium from the environment, and the piston plays a role in motion guiding.

2) The utility model discloses be provided with the uide bushing regulating ring for regulating flap's excess pressure, the uide bushing regulating ring is opened and close differential pressure to the valve simultaneously and also has certain regulatory action.

3) The structural design of disk seat, lower valve clack, push rod and push rod uide bushing makes the utility model discloses a pilot valve is under the condition of opening, and pressure differential will lead to the medium to produce continuous effort and act on valve clack down, makes the pilot valve keep the state of opening.

4) The utility model discloses a metal seal has improved the service temperature of pilot valve.

Drawings

Fig. 1 is a front cross-sectional view of a bellows balance spring type pilot valve for steam of a nuclear power station of the present invention;

fig. 2 is the utility model discloses a lateral section view of bellows balanced spring type pilot valve for nuclear power station steam.

Detailed Description

In order to understand the technical scheme of the utility model better, combine below the utility model discloses a nuclear power station is bellows balanced spring formula guide valve's for steam embodiment of assembly flow explains in detail:

referring to fig. 1 and 2, an assembly process of a bellows balanced spring type pilot valve for steam in a nuclear power plant according to the present invention includes the following steps.

1) The push rod guide sleeve 27 is connected to the valve body 23 through threads, and a gasket is arranged between the push rod guide sleeve 27 and the valve body 23 for sealing.

2) The upper valve seat 29 is screwed to the valve body 23, and a gasket is sealed between the upper valve seat 29 and the valve body 23.

3) The lower flap 24 is installed in the valve body 23 such that the sealing surface of the lower flap 24 is opposed to the sealing surface of the pushrod guide sleeve 27.

4) The lower valve seat 1 is connected to the valve body 23 through threads, and a gasket is arranged between the lower valve seat 1 and the valve body 23 for sealing. The lower opening of the lower valve seat 1 is the induction pressure interface 11 of the pilot valve.

5) The push rod 25 is installed in the push rod guide sleeve 27 from top to bottom, so that the round head of the push rod 25 is opposite to the round groove on the lower valve clack 24.

6) The adjusting ring 33 is screwed on the guide sleeve 35 through threads, the guide sleeve 35 is installed on the valve body 23 through the positioning spigot, and a gasket is arranged between the guide sleeve 35 and the valve body 23 for sealing.

7) The spacer 38 is mounted on the upper plane of the guide sleeve 35 through the positioning spigot on the valve body 23, and a sealing gasket is arranged between the spacer 38 and the guide sleeve 35.

8) The upper flap 30 is mounted on the flap seat of the bellows assembly 32 by means of a snap spring, and then the assembly of the upper flap 30 and the bellows assembly 32 is mounted in the guide sleeve 35, the sealing surface of the upper flap 30 being in contact with the sealing surface of the upper valve seat 29, the flange of the bellows assembly 32 being mounted in the spigot of the spacer 38, the flange being sealed with a gasket between the spacer 38.

9) The piston guide sleeve 41 is arranged in the spigot of the spacer sleeve 38, and the lower plane of the piston guide sleeve 41 is in contact with the plane of the flange of the bellows assembly 32.

10) The piston 40 is attached to the end of the valve stem 37 by a retainer ring, and the retainer nut 43 is screwed to the valve stem 37. The valve stem assembly is installed into the bellows assembly 32. The stop collar 42 is mounted through the valve stem 37 to the piston guide 41 as shown in fig. 1.

11) The lower spring seat 48 is attached to the stem 37, the spring 49 is attached to the lower spring seat 48, and the upper spring seat 51 is attached to the spring 49.

12) The bonnet 50 is connected to the valve body 23 through the valve stem 37 by a stud nut.

13) A lock nut 56 is threaded onto the adjustment screw 54, the adjustment screw 54 is threaded through the valve stem 37 to the bonnet 50, and the adjustment screw 54 is rotated to compress the spring 49.

14) The protective cap 60 is connected to the bonnet 50 by a stud nut.

15) An adjustment collar stud 65 is threadably mounted to the valve body 23 to fix the position of the adjustment collar 33. A gasket is arranged between the adjusting ring support pin 65 and the valve body 23 for sealing.

Wherein, the position of the adjusting limit nut 43 can limit the opening height of the pilot valve, the adjusting screw 54 can adjust the setting pressure of the pilot valve by compressing or loosening the spring 49, the locking nut 56 is used for fixing the position of the adjusting screw 54, and the adjusting ring support pin 65 is used for fixing the position of the adjusting ring 33.

The balance spring type pilot valve of the corrugated pipe for the steam of the nuclear power station cannot be used independently and needs to be arranged on a main valve to complete the overpressure protection function. During assembly, the pilot valve's sensing pressure port 11 is connected to the main valve's inlet, the pilot valve's control pressure port 12 is connected to the main valve's chamber, and the pilot valve's exhaust port 13 is connected to a closed vessel or exhaust line.

Under normal operating conditions, the pressure at the sensing pressure port 11 is the same as the pressure at the control pressure port 12. When the system pressure rises to the opening pressure of the valve, the upper valve flap 30 of the pilot valve is opened, the pressure (main valve cavity pressure) at the pilot valve control pressure interface 12 is reduced, the lower valve flap 24 is closed upwards under the action of the pressure difference, the push rod 25 is pushed under the action of the medium action force and acts on the upper valve flap 30, so that the pilot valve is kept opened, and the main valve is opened. As the main valve opens, the system pressure drops, and when the system pressure drops to the back seat pressure, the upper valve flap 30 of the pilot valve closes, while the upper valve flap 30 opens the lower valve flap 24 downwards via the push rod 25, and the pressure at the pilot pressure interface 12 of the pilot valve (the main valve chamber pressure) rises, closing the main valve. Thereby realizing the control of the opening and the closing of the main valve through the opening and the closing of the pilot valve.

It will be appreciated by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as limitations of the present invention, and that changes and modifications to the above described embodiments will fall within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.

Claims

1. The utility model provides a nuclear power station is bellows balancing spring formula pilot valve for steam, includes valve body, valve rod and sets up in disk seat subassembly, the valve clack subassembly of valve body inner chamber, its characterized in that still includes bellows subassembly and piston:

the bottom of the corrugated pipe assembly is a valve clack seat, the middle section of the corrugated pipe assembly is of a corrugated pipe structure, the top of the corrugated pipe assembly is a flange, the upper valve clack is arranged in the valve clack seat, the upper valve clack and the corrugated pipe assembly are arranged in a guide sleeve, and the guide sleeve is arranged at the top of the inner cavity of the valve body;

2. The bellows balance spring type pilot valve for nuclear power plant steam as defined in claim 1, wherein the bottom end of the push rod is round-head structure, and the top surface of the lower valve flap is provided with a round groove matching with the round-head structure.

3. The balance spring type pilot valve of the corrugated pipe for the steam of the nuclear power station as claimed in claim 1, wherein an adjusting ring is sleeved outside the guide sleeve.

4. The balance spring type pilot valve of corrugated pipe for steam in nuclear power station as claimed in claim 3, wherein the valve body is provided with an adjusting hole leading to the adjusting ring, and an adjusting ring support pin fixes the adjusting ring.

5. The balance spring type pilot valve with the corrugated pipe for the steam in the nuclear power station as claimed in claim 1, wherein a limiting sleeve is sleeved outside the valve rod, the limiting sleeve is arranged above the piston guide sleeve, a limiting nut is sleeved outside the valve rod, and the limiting nut is located inside the limiting sleeve.