A steam turbine independent control steam extraction regulating valve

Abstract

The present invention provides a steam turbine independent control steam extraction regulating valve, comprising three independently installed and jointly working first valves, second valves and third valves, the second valve is a normally open valve, the first valve and the third valve are normally closed valves with the same structure; the first valve comprises a valve seat, a valve body, a guide valve sleeve, a guide rod and a valve head, the valve seat is a hollow sleeve structure; the lower part of the valve body is fitted with a clearance to extend into the valve seat and corresponds to the upper part of the valve body; the upper part of the valve body is provided with a guide rod coaxial with the valve seat and sliding up and down through the guide valve sleeve; the lower part of the valve body is provided with a valve head which is installed and connected to the lower end of the guide rod to slide in and out of the valve body and whose lower part is in contact and sealed with the inner hole of the lower part of the valve seat; the upper end of the guide rod extends out of the guide valve sleeve and is connected to the oil motor through a coupling. The present invention provides a steam turbine independent control steam extraction regulating valve, which coordinates the steam flow through three sets of valves arranged compactly side by side to meet the operation requirements of the steam turbine under different working conditions.

Description

Technical Field

[0001] The invention relates to the technical field of steam turbine valve equipment, and in particular to an independently controlled steam extraction regulating valve for a steam turbine. Background Art

[0002] Steam turbine is the main equipment of thermal power plant. The steam inlet and exhaust flow control of steam turbine is mainly realized through the action of various regulating valves. Among them, the extraction regulating valve is the valve that regulates the flow of extraction cylinder, which is responsible for the secondary ring holding and tertiary ring holding steam inlet flow. This valve can correspond to the units equipped with medium pressure regulating valves on the market. The difference is that the medium pressure regulating valves are respectively arranged on both sides of the medium pressure cylinder and are provided with their own steam inlet and outlet to control the flow.

[0003] The valve stem and valve body of conventional steam extraction regulating valve or medium pressure regulating valve are matched with valve sleeve for sliding and sealing. The valve sleeve is a full-length structure, and the inner hole is sprayed with Stellite or nitrided before sliding with the valve stem. Due to the long valve stem, the spray layer will fall off after long-term operation, the straightness is easy to exceed the tolerance, the oxide scale is serious, and the jamming phenomenon is frequent.

[0004] The valve seat of a conventional extraction steam regulating valve or medium-pressure regulating valve is assembled to the valve body by interference fit and fixed by welding. It is generally impossible to disassemble it. After long-term operation, if the valve seat is damaged, it can only be broken down and replaced with a new one. The maintenance and installation costs are high and it is not easy to operate on site.

[0005] During the operation of the steam turbine unit, the valve stem and valve head are required not to rotate relative to the valve seat. Usually, an anti-rotation key and a positioning pin are set between the valve stem and the valve head to connect and fix them. The structure is complex in design, and after long-term operation, it is affected by superheated steam, and the connection position is severely oxidized, making disassembly and maintenance difficult. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a steam turbine independently controlled steam extraction regulating valve, which coordinates the steam flow through three sets of valves arranged compactly side by side to meet the operation requirements of the steam turbine under different working conditions.

[0007] The technical solution adopted by the invention is: a steam turbine independently controlled steam extraction regulating valve, comprising a first valve, a second valve and a third valve which are independently installed and work together, the second valve is a normally open valve, and the first valve and the third valve are normally closed valves with the same structure;

[0008] The first valve comprises a valve seat, a valve body, a guide valve sleeve, a guide rod and a valve head, wherein the valve seat is a hollow sleeve structure, the upper part of the valve seat is clamped in a preset stepped groove of the high-pressure cylinder and partially extends out of the high-pressure cylinder, the middle part of the valve seat extends downward to the inside of the high-pressure cylinder and a steam inlet hole is provided along the circumferential direction of the side wall, and the lower part of the valve seat is clamped in cooperation with the steam inlet of the extraction cylinder in the high-pressure cylinder; the lower clearance of the valve body is fitted to extend into the valve seat and corresponds to the upper part of the valve body, and the top surface of the valve body corresponding to the valve seat is provided with a disc-shaped structure extending outward with a stopper and clamped and fixed with the valve seat, and the outer side of the stopper extends outward and is provided with a flange with a flange hole for connecting with the high-pressure cylinder; the upper part of the valve body is provided with a guide rod coaxial with the valve seat and sliding up and down through the guide valve sleeve; the lower part of the valve body is provided with a valve head which is connected to the lower end of the guide rod and slides in and out of the valve body and whose lower part is in contact and sealed with the inner hole of the lower part of the valve seat; the upper end of the guide rod extends out of the guide valve sleeve and is connected to the oil motor through a coupling;

[0009] The guide valve sleeve is installed in a step-shaped guide hole opened at the upper port of the valve body, and the upper end of the guide valve sleeve is installed with a locking nut whose lower part is screwed on the upper inner wall of the guide hole through threads and whose upper part extends out of the guide hole;

[0010] The guide rod is connected to the valve head through a locking rod nut, the lower end of the guide rod is set as a step shaft structure, the locking rod nut is inserted from the top of the guide rod and installed on the step shaft at the lower end of the guide rod, the outer wall of the lower part of the locking rod nut is screwed into the threaded blind hole preset in the center of the top of the valve head through an external thread, and a radial positioning pin for fixing and preventing loosening is installed between the locking rod nut and the valve head;

[0011] The upper part of the valve head is installed in the end hole below the guide hole of the valve body through the guide sleeve and slides up and down along the guide sleeve;

[0012] The lower part of the valve head extends outward from the bottom of the guide sleeve and extends horizontally outward, then folds back vertically upward to form a cup-shaped structure with an open upper part. A circle of axial balancing through holes is provided in the extended section of the valve head. The inner side wall of the folded section of the valve head slides with a convex ring preset on the outer valve body of the guide sleeve. The outer side wall of the connection between the extended section of the valve head and the folded section is processed into a circular arc sealing surface that contacts and seals with a circular arc surface preset in the inner hole of the lower part of the valve seat.

[0013] The valve head is provided with a central through hole along the axis, an axial steam hole connected to the central through hole is provided at the lower part of the step shaft at the lower end of the guide rod, a radial steam hole connected to the axial steam hole is provided at the upper part of the step shaft, and a balancing steam hole connected to the radial steam hole and the top of the inner hole of the valve head installation end is provided at the upper part of the lock rod nut;

[0014] Compared with the structure of the first valve, the second valve is additionally provided with a travel lock assembly installed between the locking nut and the coupling. A guide rod through hole is provided in the center of the travel lock assembly. The lower part of the travel lock assembly is sleeved on the upper part of the locking nut and the protruding end of the locking nut is tightened by the internal thread. The top surface of the travel lock assembly is installed with a plurality of adjustable gaskets and gaskets that are against the bottom surface of the coupling through screws to adjust the height of the guide rod to drive the valve head to leave the valve seat.

[0015] As a further limitation of the above technical solution, a guide block is fixedly installed on the outer side wall of the upper part of the valve head, a knockout thread for disassembly is arranged on the guide block, and an axial guide groove cooperating with the guide block is arranged on the guide sleeve.

[0016] As a further limitation of the above technical solution, the guide sleeve is a stepped sleeve that is smaller at the top and larger at the bottom. A locating pin is installed on the end face of the stepped hole provided in cooperation with the valve body. A locating groove is provided on the stepped surface of the guide sleeve correspondingly. An exit threaded hole is provided axially on the large head end of the guide sleeve.

[0017] As a further limitation of the above technical solution, a convex ring matching the inner diameter of the return section is provided at the large head end of the guide sleeve corresponding to the valve body, and an annular groove extending to the bottom surface is provided on the outer wall in the middle of the convex ring, and a piston ring and a spacer ring are installed in the upper part of the annular groove, and a circle of locking grooves is provided on the side wall of the annular groove corresponding to the bottom surface of the spacer ring, and a locking ring is embedded in the locking groove, the inner side of which is fastened to the convex ring by rivets and the outer side supports the spacer ring.

[0018] As a further limitation of the above technical solution, the guide valve sleeve includes a plurality of graphite ring groups and carbon pressure ring bushings pressed on both ends, and the carbon pressure ring bushing includes a body and a graphite ring embedded in the body.

[0019] As a further limitation of the above technical solution, an adjusting wrench for providing tightening force is fixed to the upper portion of the locking nut of the first valve extending out of the guide hole.

[0020] As a further limitation of the above technical solution, the coupling includes a main body, a safety plate and a T-nut. The lower part of the output shaft of the oil motor is installed in a threaded hole pre-opened in the center of the top of the main body through threaded matching. The lower part of the main body is provided with a notched groove that is transparent front and back and passes through the threaded hole. The top of the notched groove is clamped and fixed with a safety plate that is pre-set in a directional flat fit with the bottom of the output shaft of the oil motor; the notched groove below the safety plate is provided with a T-slot with a vertical cross-section that is transparent front and back and is T-shaped. A T-nut is installed in the T-slot, the upper end of the guide rod is threadedly installed in the threaded hole pre-set in the center of the T-nut, and the side of the T-nut is provided with a screw that radially extends into the pre-set anti-rotation groove in the side wall of the guide rod.

[0021] As a further limitation of the above technical solution, the directional flat is a cuboid with a rectangular cross-section, and a positioning groove matching the directional flat is opened in the center of the safety plate. The groove edge of the positioning groove fits tightly with the short side of the directional flat and has a gap with the long side of the directional flat.

[0022] As a further limitation of the above technical solution, the oil motor is fixedly connected to the valve body through a hollow oil motor valve column, and the two ends of the oil motor valve column are connected to the oil motor and the valve body through a flange with a stop structure and bolts;

[0023] A heat insulation plate is installed on the top surface of the main body, and a heat dissipation hole is arranged on the side wall of the oil motor valve column.

[0024] As a further limitation of the above technical solution, the upper portion of the locking nut is a smooth rod nut head whose diameter is smaller than the inner diameter of the thread of the mating section of the travel lock assembly, and the travel lock assembly has a corresponding stepped hole and is arranged as a two-half structure that is positioned by a locating pin and locked by a screw, and the outer wall of the travel lock assembly has a dial hole for easy dialing and tightening.

[0025] By adopting the above technology, the advantages of the present invention are:

[0026] The present invention discloses a design structure and control function of an independently controlled steam extraction regulating valve for a steam turbine. The valve adopts a modular design and is composed of three independent regulating valve bodies to form an extraction regulating valve, which is directly installed on the high-pressure cylinder body. The inlet steam is the steam after the first-stage holding ring in the high-pressure cylinder has done work. The steam outlets of the three valves are all connected to the extraction cylinder sleeve provided in the high-pressure cylinder, and the steam is output to the second-stage holding ring and the third-stage holding ring to do work through the extraction cylinder sleeve. Each valve can independently act to adjust its own steam flow rate, and can also coordinate the steam flow rate together to meet the operation requirements of the steam turbine under different working conditions. They are arranged side by side with a compact structure, which can save installation space to the maximum extent, and are particularly suitable for the operation control of reaction steam turbines.

[0027] In the present invention, the guide rod slides up and down in the guide valve sleeve. The guide valve sleeve is set to replace the traditional valve sleeve and adopts supersonic spraying Stellite technology and nitriding technology, which effectively avoids the problems of Stellite falling off, layer loss, low life of hardened layer, and jamming after long-term operation. The guide valve sleeve has the characteristics of low hardness, high temperature resistance, corrosion resistance, and wear resistance, effectively protects the contact surface of the valve stem and improves the service life.

[0028] The present invention adopts a replaceable valve seat structure, one end of which is mounted on the cylinder port of the high-pressure cylinder, and the other end is mounted on the end face of the valve body. This process can replace traditional valve seats that are difficult to disassemble or even cannot be disassembled, such as welded fixed valve seats or interference fit valve seats, and can meet the needs of rapid repair or replacement of valve seats during on-site maintenance, greatly reducing maintenance time and reducing maintenance costs.

[0029] In the present invention, the guide rod and the valve head are two-body structures, the valve head slides in the guide sleeve, and the valve rod slides in the guide valve sleeve. At the same time, the guide rod and the valve head are provided with independent anti-rotation structures, which makes disassembly and maintenance faster. This modular design structure can not only meet the ultra-large flow diameter required by the valve head, but also meet the requirements of rapid disassembly during on-site shutdown and maintenance, thereby reducing maintenance time and maintenance costs.

[0030] In the present invention, the output shaft of the oil motor is connected to the guide rod through the coupling, and the oil motor is connected to the valve body through the oil motor valve column, so that the effective connection of the valve components is achieved. The heat insulation plate arranged on the coupling and the heat dissipation holes arranged on the oil motor valve column can block the influence of steam heat on the oil motor and ensure its normal operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the first valve and the third valve of the present invention;

[0032] Figure 2 for Figure 1 A magnified view of middle;

[0033] Figure 3 for Figure 1 Enlarged view of middle B;

[0034] Figure 4 It is a structural schematic diagram of the guide valve head of the present invention;

[0035] Figure 5 It is a schematic diagram of the connection between the coupling and the oil motor of the present invention;

[0036] Figure 6 for Figure 1 Sectional view of EE;

[0037] Figure 7 for Figure 1 Cross-sectional view of the middle DD;

[0038] Figure 8 is a schematic structural diagram of a second valve of the present invention;

[0039] Fig. 9 It is a structural schematic diagram of the travel lock assembly of the present invention;

[0040] Fig.10 It is a schematic diagram of the connection between the valve of the present invention and the high-pressure cylinder and the steam extraction cylinder.

[0041] In the figure: 1-valve seat; 111-steam inlet hole;

[0042] 2-valve body;

[0043] 3-guide valve sleeve; 301-graphite ring set; 302-carbon pressure ring bushing; 303-locking nut; 304-adjusting wrench;

[0044] 5-valve head; 501-guide sleeve; 502-guide block; 503-axial guide groove; 504-exit threaded hole; 505-balance through hole; 506-convex ring; 507-piston ring; 508-spacer ring; 509-locking ring; 510-rivet; 511-locking rod nut; 512-axial steam hole; 513-radial steam hole; 514-balance steam hole; 515-flanging feature;

[0045] 6-high pressure cylinder; 7-guide rod;

[0046] 8-coupling; 801-main body; 802-safety plate; 803-T-nut; 804-directional flat; 805-heat insulation board;

[0047] 9- oil motor; 901- oil motor valve column; 902- heat dissipation hole;

[0048] 10-travel lock assembly; 101-adjustable gasket; 102-backing plate; 103-dial hole;

[0049] 11-Pump cylinder. DETAILED DESCRIPTION

[0050] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0051] Example 1

[0052] like Figure 1-10 As shown, a steam turbine independently controlled steam extraction regulating valve includes three independently installed first valves, second valves and third valves working together on the high-pressure cylinder. The second valve is located in the middle and is a normally open valve, and maintains a certain valve opening. The first valve and the third valve are located at both ends and have the same structure and are both normally closed valves. The steam outlets of the three valves correspond to the three steam inlets of the steam extraction cylinder 11 and jointly adjust the steam inlet flow rate to meet the requirements of the second and third stage ring holding work of the steam turbine.

[0053] like Figure 1 As shown, the first valve comprises a valve seat 1 , a valve body 2 , a guide valve sleeve 3 , a guide rod 7 and a valve head 5 .

[0054] The connection between the exhaust regulating valve and the high pressure cylinder 6 and the exhaust cylinder 11 is as follows: Fig.10As shown, the valve seat 1 is a hollow sleeve structure. The upper part of the valve seat 1 is clamped in the preset stepped groove of the high-pressure cylinder 6 and partially extends out of the high-pressure cylinder 6. The middle part of the valve seat 1 extends downward to the inside of the high-pressure cylinder 6 and opens a steam inlet hole 111 along the circumferential direction of the side wall. The lower part of the valve seat 1 is clamped at the steam inlet of the extraction cylinder 11 in the high-pressure cylinder 6. The lower part of the valve body 2 is fitted with a clearance to extend into the valve seat 1 and corresponds to the upper part of the valve body 2. The valve body 2 is provided with a disc-shaped structure with a stopper extending outward on the top surface of the valve seat 1 and is clamped and fixed with the valve seat 1. The outer side of the stopper extends outward and is provided with a flange with a flange hole for connecting with the high-pressure cylinder 6. The upper part of the valve body 2 is provided with a guide rod 7 coaxial with the valve seat 1 and sliding up and down through the guide valve sleeve 3; the lower part of the valve body 2 is provided with a valve head 5, which is installed and connected to the lower end of the guide rod 7 and slides in and out of the valve body 2, and the lower part of the valve head 5 is in contact and sealed with the inner hole of the lower part of the valve seat 1, so as to realize the closing and opening of the air extraction regulating valve. The upper end of the guide rod 7 extends out of the guide valve sleeve 3 and is connected to the oil motor 9 through the coupling 8.

[0055] The number of the steam inlet holes 111 is 6-8, and the axis of the steam inlet hole 111 forms an acute angle with the axis of the valve seat 1, which is used to reduce steam resistance and increase steam extraction flow rate. The flange hole on the top surface of the valve body 2 corresponding to the valve seat 1 is equipped with studs and nuts to fix the valve body 2 to the upper cylinder of the high-pressure cylinder 6, and then the valve body 2 is clamped on the valve seat 1.

[0056] The upper part of the valve head 5 is a cylindrical structure, which is arranged in an end hole opened inside the valve body 2 and connected to the lower part of the guide hole through a guide sleeve 501. The valve head 5 slides up and down along the guide sleeve 501, and the sliding positioning function is realized by setting the guide sleeve 501. The axis of the valve head 5, the axis of the valve seat 1, and the axis of the valve body 2 are coaxially arranged to ensure that the guide sleeve 501 and the outer wall of the valve head 5 slide in cooperation. The outer wall of the upper part of the valve head 5 is installed with a guide block 502 by screws. The guide block 502 is a rectangular key. The guide block 502 is provided with a knockout thread for disassembly. An axial guide groove 503 cooperating with the guide block 502 is provided on the guide sleeve 501 along the vertical axis. The guide block 502 can move up and down along the axial guide groove 503, thereby realizing the anti-rotation function of the valve head 5.

[0057] The guide sleeve 501 is heat-fitted onto the valve body 2 in an interference fit manner. The guide sleeve 501 is a stepped sleeve with a small top and a large bottom. The end face of the valve body 2 is the stepped hole end face that matches the guide sleeve 501. A positioning pin is installed on the stepped hole end face. A positioning groove is correspondingly provided on the stepped surface of the guide sleeve 501, thereby realizing the anti-rotation function of the guide sleeve 501. The exit threaded hole 504 is provided axially at the large end of the guide sleeve 501. During the disassembly process, a disassembly tool is screwed into the exit threaded hole 504. After the disassembly tool supports the stepped hole end face of the valve body 2, the guide sleeve 501 is ejected in the reverse direction. After the guide sleeve 501 is installed in place, the flange feature 515 pre-set at the bottom can be bent as a whole and filled into the groove provided in the corresponding inner hole of the valve body 2, thereby ensuring the stability of the guide sleeve 501 during the operation of the unit.

[0058] The lower part of the valve head 5 extends out from the bottom of the guide sleeve 501 and extends horizontally outwards and then folds back vertically upwards to form a cup-shaped structure with an open upper part. The extended section of the valve head 5 is provided with a circle of axial balance through holes 505. A convex ring 506 is preset on the valve body 2 outside the guide sleeve 501. The convex ring 506 is slidably matched with the inner side wall of the folded section of the valve head 5. The outer side wall of the connection between the extended section of the valve head 5 and the folded section is processed into a circular arc sealing surface that contacts and seals with the preset circular arc surface of the lower inner hole of the valve seat 1, and cooperates with the seal to realize the opening and closing of the exhaust regulating valve.

[0059] The connection between the valve head 5 and the valve body 2 is as follows Figure 2 As shown, the diameter of the small end of the guide sleeve 501 corresponding to the valve body 2 is smaller than the inner diameter of the return section of the valve head 5, and a convex ring 506 is provided at the large end of the guide sleeve 501 corresponding to the valve body 2, and the convex ring 506 matches the inner diameter of the return section. The outer wall of the middle part of the convex ring 506 is provided with a ring groove extending to the bottom surface, and the upper part of the ring groove is sequentially installed with a piston ring 507 and a spacer ring 508 from top to bottom. The side wall of the ring groove corresponding to the bottom surface of the spacer ring 508 is provided with a circle of locking grooves, and a locking ring 509 is embedded in the locking groove. The inner side of the locking ring 509 is fastened to the convex ring 506 by rivets 510, and the outer side supports the spacer ring 508. The locking ring 509 is protected by the spacer ring 508 and the axial movement of the piston ring 507 is blocked. The outer side of the piston ring 507 is provided with high and low slopes, the high end direction is the same as the direction of the valve seat 1, and the low end direction is opposite to the direction of the valve seat 1, thereby realizing the self-lubrication and sealing function of the folded section of the valve head 5 during the forward and backward movement.

[0060] The connection between the valve head 5 and the guide rod 7 is as follows Figure 3As shown, the top of the valve head 5 is connected to the guide rod 7 through a locking rod nut 511, and the lower end of the guide rod 7 is set as a stepped shaft structure with an inner blind hole and an outer optical axis. The locking rod nut 511 passes through the top of the guide rod 7 and is installed on the stepped shaft of the guide rod 7. A threaded blind hole is preset at the top center of the valve head 5, and the outer side wall of the lower part of the locking rod nut 511 is screwed into the threaded blind hole through an external thread. When the locking rod nut 511 and the valve head 5 are tightened, a positioning pin is installed at a radial position. The locking rod nut 511 and the valve head 5 are fixed and prevented from loosening.

[0061] The valve head 5 is provided with a central through hole along the axis, the lower part of the step shaft at the lower end of the guide rod 7 is provided with an axial steam hole 512 connected to the central through hole of the valve head, the upper part of the step shaft is provided with a radial steam hole 513 connected to the axial steam hole 512, and the upper part of the lock rod nut 511 is provided with a balance steam hole 514 connected to the radial steam hole 513 and below the guide hole. The axial steam hole 512, the radial steam hole 513 and the balance steam hole 514 are all connected. When the valve head moves to open, the steam enters the valve seat 1 from the steam inlet hole 111, and flows into the balance steam hole 514 along the central through hole, and finally reaches between the valve body 2 and the guide sleeve 501, that is, the top of the lower end hole of the valve body 2 and the position below the guide hole, so that the steam at the valve head 5 and the valve seat 1, and the steam at the valve head 5 and the valve body 2 are connected and the pressure is the same in the working state, ensuring the normal stroke action of the valve head 5 and the guide rod 7.

[0062] The structure of the guide valve sleeve 3 is as follows: Figure 4 As shown, the guide valve sleeve 3 is installed in the step-shaped guide hole opened at the upper port of the valve body 2, and the guide valve sleeve 3 is used to realize the sliding guide and steam sealing functions. The guide valve sleeve 3 includes a plurality of graphite ring groups 301, and the graphite ring groups 301 are formed by stacking 6-8 groups of graphite sealing rings. Carbon pressure ring bushings 302 are pressed at both ends of the graphite ring group 301 to protect the graphite ring group 301. The carbon pressure ring bushing 302 includes a body made of heat-resistant alloy steel and a graphite ring embedded in the body. The graphite ring has the characteristics of low hardness, high temperature resistance, corrosion resistance, and wear resistance, which effectively protects the contact surface with the guide rod 7 and improves the service life. The upper end face of the carbon pressure ring bushing 302 located at the top is installed with a locking nut 303, and the lower part of the locking nut 303 is screwed on the upper inner wall of the guide hole through a thread, and the upper part extends out of the guide hole.

[0063] The connection between the coupling 8 and the oil motor 9 is as follows Figure 5 , Figure 6As shown, the coupling 8 includes a main body 801, a safety plate 802 and a T-nut 803. The lower part of the output shaft of the oil motor 9 is provided with an external thread, and the lower end of the external thread is processed with a rectangular parallelepiped directional flat 804. A threaded hole is provided at the top center of the main body 801, and the lower part of the output shaft of the oil motor 9 is installed in the threaded hole through threaded matching. The top surface of the main body 801 is installed with a heat insulation plate 805 by screws, which blocks the heat conduction of the high temperature of the valve body 2 to the oil motor 9 under the working state. A notch groove that is transparent from front to back and passes through the threaded hole is provided at the lower part of the main body 801, and the top of the notch groove is clamped and fixed with a safety plate 802. The center of the safety plate 802 is provided with a positioning groove that matches the directional flat 804, and the groove edge of the positioning groove is tightly matched with the short side of the directional flat 804, and is gap matched with the long side of the directional flat 804. The safety plate 802 is matched with the directional flat 804 preset at the bottom of the output shaft of the oil motor 9, so that the fixed anti-rotation function of the output shaft of the oil motor 9 and the coupling 8 is realized.

[0064] The notch below the safety plate 802 is provided with a T-shaped vertical cross section that is transparent from front to back, and a T-shaped nut 803 is installed in the T-shaped slot. A threaded hole is provided in the center of the T-shaped nut 803, and the upper end of the guide rod 7 is installed in the threaded hole through a thread, and the connection between the guide rod 7 and the output shaft of the oil motor 9 is fixed by the coupling 8. A radial screw is installed on the side of the T-shaped nut 803, and the radial screw extends into the anti-rotation groove preset in the side wall of the guide rod, thereby realizing the relative anti-rotation function between the guide rod 7 and the T-shaped nut 803, and the anti-rotation groove is a keyway or a countersunk hole.

[0065] The oil motor 9 is fixedly connected to the valve body 2 through a hollow oil motor valve column 901. The two ends of the oil motor valve column 901 are connected to the oil motor 9 and the valve body 2 through flanges with stopper structures and bolts. The stopper structures at both ends of the oil motor 9 are positioned to achieve the coaxiality of the output shaft of the oil motor 9 and the guide rod 7. The side wall of the oil motor valve column 901 is provided with heat dissipation holes 902. The number of the heat dissipation holes 902 is 4-6. The shape of the heat dissipation holes 902 is a square hole or a round hole. The oil motor valve column 901 is set up to quickly dissipate high temperature, thereby ensuring the normal operation of the oil motor 9.

[0066] When the oil motor 9 and the coupling 8 are disassembled, the output shaft of the oil motor 9 is withdrawn through the oil motor 9, and the coupling 8 and the guide rod 7 are withdrawn at the same time. When the bottom surface of the coupling body 801 leaves the top surface of the valve body 2, it is the maximum withdrawal position. By removing the bolts and nuts fixing the oil motor valve column 901, the coupling 8, the oil motor valve column 901, and the oil motor 9 are separated from the T-slot of the T-nut 803, and then the oil motor 9, the coupling 8 and the guide rod 7 are disassembled.

[0067] The structure of the second valve is as follows Figure 8As shown, the structure of the second valve is basically the same as that of the first valve, except that a travel lock assembly 10 is additionally provided. Fig. 9 As shown, the travel lock assembly 10 is installed between the locking nut 303 and the main body 801 of the coupling. A guide rod through hole is provided in the center of the travel lock assembly 10; the lower part of the travel lock assembly 10 is sleeved on the upper part of the locking nut 303, and the protruding end of the locking nut 303 is tightened by the internal thread; the top surface of the travel lock assembly 10 is installed with a plurality of adjustable gaskets 101 and pads 102 from bottom to top by screws, and the pad 102 located at the top is against the bottom surface of the main body 801. By increasing or decreasing the thickness of the adjustable gasket 101 and the pad 102, the height of the guide rod 7 driving the valve head 5 to leave the valve seat 1 is adjusted, thereby adjusting the opening of the valve. The adjustable gasket 101 and the pad 102 are composed of a plurality of stainless steel sheets of unequal thickness. The stainless steel sheets are all in a two-half structure, and the thickness is set to 0.15mm, 0.2mm, 0.5mm, 3mm and other specifications.

[0068] In order to facilitate installation, the upper part of the locking nut 303 is a bare rod nut head with a diameter smaller than the inner diameter of the thread of the matching section of the travel lock assembly 10. The travel lock assembly 10 has a corresponding hole for clamping the nut head, and the travel lock assembly 10 has a corresponding stepped hole and is set as a two-half structure that is buckled. In order to ensure that the internal thread of the travel lock assembly 10 is engaged and aligned, it is necessary to first insert the positioning pin into the pin hole for positioning, and then tighten it with a screw. The outer wall of the travel lock assembly 10 is provided with a shifting hole 103 that is radially connected to the side wall of the nut head and is easy to turn and tighten. By inserting a shifting rod into the shifting hole 103, the travel lock assembly 10 and the locking nut 303 can be smoothly tightened and fixed.

[0069] Adjustment wrench Figure 7 As shown, in order to facilitate the adjustment of the appropriate clamping force, the upper part of the locking nut 303 of the first valve and the third valve extending out of the guide hole is fixed with an adjusting wrench 304 for providing the tightening force. By rotating the adjusting wrench 304 to a certain angle, the locking nut 303 can be screwed into the valve body 2 and the carbon pressure ring bushing 302 can be pressed to provide a suitable matching clamping force, thereby achieving the best self-lubrication and sealing performance when the guide rod 7 and the valve body 2 slide.

[0070] The present embodiment describes a steam turbine independently controlled steam extraction regulating valve. During operation, the second valve is a normally open valve to ensure a certain amount of air intake. The oil motor 9 of the first valve and the third valve drives the guide rod 7 to move up and down in the guide valve sleeve 3 through the coupling 8. The guide rod 7 drives the valve head 5 to move up and down in the guide sleeve 501. During the upward movement of the valve head 5, the arc sealing surface of the valve head 5 leaves the arc surface of the valve seat 1, and the steam enters the valve seat 1 from the steam inlet hole 111 and is transported to the steam extraction cylinder 11. By adjusting the distance between the valve head 5 and the valve seat 1, the purpose of adjusting the steam flow is achieved.

[0071] The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technical solution obtained by any technician familiar with the field within the technical scope disclosed by the present invention by equivalent replacement or change based on the technical concept of the present invention should be included in the protection scope of the present invention.

Claims

1. A steam turbine independently controlled steam extraction regulating valve, characterized in that: It comprises a first valve, a second valve and a third valve which are independently installed and work together, the second valve is a normally open valve, and the first valve and the third valve are normally closed valves with the same structure; The first valve comprises a valve seat (1), a valve body (2), a guide valve sleeve (3), a guide rod (7) and a valve head (5); the valve seat (1) is a hollow sleeve structure; the upper part of the valve seat (1) is clamped in a preset stepped groove of the high-pressure cylinder (6) and partially extends out of the high-pressure cylinder (6); the middle part of the valve seat (1) extends downward to the inside of the high-pressure cylinder (6) and is provided with a steam inlet hole (111) along the circumference of the side wall; the lower part of the valve seat (1) is clamped in a matching manner at the steam inlet of the extraction cylinder (11) in the high-pressure cylinder (6); the lower part of the valve body (2) is clearance-matched to extend into the valve seat (1) and corresponds to the upper part of the valve body (2); the valve body (2) corresponds to the valve seat (1 ) is provided with a disc-shaped structure with a stopper extending outward and fixed to the valve seat (1), and the outer side of the stopper extends outward and is provided with a flange with a flange hole for connecting to the high-pressure cylinder (6); the upper part of the valve body (2) is installed with a guide rod (7) coaxial with the valve seat (1) and sliding up and down through the guide valve sleeve (3); the lower part of the valve body (2) is provided with a valve head (5) which is installed and connected to the lower end of the guide rod (7) and slides in and out of the valve body (2), and the lower part of which is in contact and sealed with the inner hole of the lower part of the valve seat (1); the upper end of the guide rod (7) extends out of the guide valve sleeve (3) and is connected to the oil motor (9) through the coupling (8); The guide valve sleeve (3) is installed in a step-shaped guide hole opened at the upper port of the valve body (2); the upper end of the guide valve sleeve (3) is installed with a locking nut (303) whose lower part is screwed on the upper inner wall of the guide hole through a thread and whose upper part extends out of the guide hole; The guide rod (7) is connected to the valve head via a locking rod nut (511); the lower end of the guide rod (7) is arranged as a stepped shaft structure; the locking rod nut (511) is inserted from the top of the guide rod and installed on the stepped shaft at the lower end of the guide rod (7); the outer wall of the lower part of the locking rod nut (511) is screwed into a threaded blind hole preset in the center of the top of the valve head via an external thread; a radial positioning pin for fixing and preventing loosening is installed between the locking rod nut (511) and the valve head (5); The upper part of the valve head (5) is installed in the end hole below the guide hole of the valve body (2) through the guide sleeve (501) and slides up and down along the guide sleeve (501); the lower part of the valve head (5) extends out of the bottom of the guide sleeve (501) and extends horizontally outward and then folds back vertically upward to form a cup-shaped structure with an open upper part. The extended section of the valve head (5) is provided with a circle of axial balancing through holes (505). The inner side wall of the folded section of the valve head (5) is slidably matched with a convex ring (506) preset on the outer valve body (2) of the guide sleeve (501). The outer side wall of the connection between the extended section and the folded section of the valve head (5) is processed into a circular arc sealing surface that contacts and seals with the circular arc surface preset in the lower inner hole of the valve seat (1); The valve head (5) is provided with a central through hole along the axis, an axial steam hole (512) communicating with the central through hole is provided at the lower part of the step shaft at the lower end of the guide rod (7), a radial steam hole (513) communicating with the axial steam hole (512) is provided at the upper part of the step shaft, and a balancing steam hole (514) communicating with the radial steam hole (513) and the top of the mounting end hole of the valve head (5) is provided at the upper part of the locking rod nut (511); Compared with the structure of the first valve, the second valve is additionally provided with a travel lock assembly (10) installed between the locking nut (303) and the coupling (8); a guide rod through hole is provided at the center of the travel lock assembly (10); the lower part of the travel lock assembly (10) is sleeved on the upper part of the locking nut (303) and the protruding end of the locking nut (303) is screwed through the internal thread; the top surface of the travel lock assembly (10) is installed with a plurality of adjustable gaskets (101) and gaskets (102) that are against the bottom surface of the coupling (8) and are used to adjust the height of the guide rod (7) driving the valve head (5) to leave the valve seat (1); A guide block (502) is fixedly mounted on the outer side wall of the upper part of the valve head (5), a push-out thread for disassembly is provided on the guide block (502), and an axial guide groove (503) cooperating with the guide block (502) is provided on the guide sleeve (501); The guide sleeve (501) is a stepped sleeve with a smaller top and a larger bottom. A positioning pin is installed on the end face of the stepped hole provided in cooperation with the valve body (2). A positioning groove is provided on the stepped surface of the guide sleeve (501) correspondingly. An exit threaded hole (504) is provided on the large end of the guide sleeve (501) along the axial direction.

2. The steam turbine independently controlled steam extraction regulating valve according to claim 1, characterized in that: A convex ring (506) matching the inner diameter of the folded section is arranged at the large end of the guide sleeve (501) corresponding to the valve body (2); an annular groove extending to the bottom surface is arranged on the outer wall in the middle of the convex ring (506); a piston ring (507) and a spacer ring (508) are installed in the upper part of the annular groove; a locking groove is arranged on the side wall of the annular groove corresponding to the bottom surface of the spacer ring (508); a locking ring (509) is embedded in the locking groove, the inner side of which is fastened to the convex ring (506) by rivets and the outer side of which supports the spacer ring (508).

3. The turbine independent control steam extraction regulating valve according to claim 1, characterized in that: The guide valve sleeve (3) comprises a plurality of graphite ring groups (301) and carbon pressure ring bushings (302) pressed on both ends, and the carbon pressure ring bushings (302) comprise a body and a graphite ring embedded in the body.

4. The steam turbine independently controlled steam extraction regulating valve according to claim 1, characterized in that: An adjusting wrench (304) for providing tightening force is fixed to the upper portion of the locking nut (303) of the first valve that protrudes out of the guide hole.

5. The steam turbine independently controlled steam extraction regulating valve according to claim 1, characterized in that: The coupling (8) comprises a main body (801), a safety plate (802) and a T-shaped nut (803); the lower part of the output shaft of the oil motor (9) is installed in a threaded hole pre-opened in the center of the top of the main body (801) through threaded matching; the lower part of the main body (801) is provided with a notched groove that is transparent from front to back and passes through the threaded hole; the top of the notched groove is clamped and fixed with a safety plate (802) that is matched with a directional flat (804) pre-set at the bottom of the output shaft of the oil motor (9); the notched groove below the safety plate (802) is provided with a T-shaped vertical cross-section that is transparent from front to back, and the T-shaped nut (803) is installed in the T-shaped groove; the upper end of the guide rod (7) is installed in the threaded hole pre-set in the center of the T-shaped nut (803) through threaded matching; and the side of the T-shaped nut (803) is provided with a screw that radially extends into the anti-rotation groove pre-set in the side wall of the guide rod (7).

6. The steam turbine independently controlled steam extraction regulating valve according to claim 5, characterized in that: The directional flat (804) is a cuboid with a rectangular cross section. A positioning groove matching the directional flat (804) is provided at the center of the safety plate (802). The groove edge of the positioning groove is tightly matched with the short side of the directional flat (804) and has a gap with the long side of the directional flat (804).

7. The turbine independent control steam extraction regulating valve according to claim 5, characterized in that: The oil motor (9) is fixedly connected to the valve body (2) via a hollow oil motor valve column (901), and the two ends of the oil motor valve column (901) are connected to the oil motor (9) and the valve body (2) via a flange with a stop structure and bolts; A heat insulation plate (805) is installed on the top surface of the main body (801), and a heat dissipation hole (902) is provided on the side wall of the hydraulic motor valve column (901).

8. The steam turbine independently controlled steam extraction regulating valve according to claim 1, characterized in that: The upper portion of the locking nut (303) is a smooth rod nut head having a diameter smaller than the inner diameter of the thread of the section that cooperates with the travel lock assembly (10); the travel lock assembly (10) is provided with a corresponding stepped hole and is arranged as a buckled two-half structure positioned by a positioning pin and locked by a screw; the outer side wall of the travel lock assembly (10) is provided with a dial hole (103) for easy dialing and tightening.

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