An angle-type large pressure difference molten salt regulating valve

Abstract

An angle-type large-pressure-difference molten salt regulating valve belongs to the technical field of solar thermal power generation and energy storage. The present invention aims to solve the problem of large pressure difference in existing molten salt regulating valves, which easily causes valve core vibration. The valve body comprises a throttling sleeve assembly provided on the flow path of the medium, the throttling sleeve assembly comprising a main valve sleeve, a four-stage valve sleeve, a three-stage valve sleeve, a two-stage valve sleeve, and a first-stage valve sleeve, which are sequentially sleeved on the main valve sleeve from the inside to the outside, a plurality of throttling flow holes provided on the first-stage valve sleeve, and a plurality of throttling stepped holes provided on the four-stage valve sleeve, the three-stage valve sleeve, the two-stage valve sleeve, and the main valve sleeve. The throttling stepped holes are composed of a contraction hole section and an expansion hole section connected inside and outside. The plurality of throttling flow holes and the plurality of throttling stepped holes on the two-stage valve sleeve, the three-stage valve sleeve, the four-stage valve sleeve, and the main valve sleeve are connected in sequence in a one-to-one correspondence. When the medium flows through the throttling sleeve assembly, the energy of the medium is consumed more, thereby better suppressing the vibration of the valve core and more significantly reducing the valve noise.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar thermal power generation and energy storage, and in particular relates to an angular large pressure difference molten salt regulating valve. Background Art

[0002] The high-pressure differential molten salt regulating valve, installed in the molten salt pipeline below the CSP generator, controls the flow of molten salt. Its control performance is crucial to the safe and reliable operation of the entire unit. Its operating characteristics are: a medium temperature of 575°C, a pressure differential of 4-5 MPa, and a flowing medium of binary or ternary molten salt.

[0003] Current problems with large-pressure-difference molten salt regulating valves include: Due to the large pressure differential of large-pressure-difference molten salt regulating valves, the existing single-stage window throttling method is prone to valve core vibration. Some use labyrinth disc throttling, which is prone to blockage and salt accumulation. In addition, the flow capacity of labyrinth regulating valves of the same caliber is small and cannot meet the flow requirements of the unit. The existing valve flange is sealed with a spiral wound gasket. Due to the high medium temperature during the day and the low temperature during shutdown at night, the spiral wound gasket is exposed to the temperature alternation for a long time and fails, resulting in medium leakage from the flange. Due to the high medium temperature and high density of molten salt, the existing gap between the valve core and the sleeve is too large, causing valve vibration and loud noise. In some cases, the gap between the valve core and the sleeve is too small, causing the valve stem to become stuck and difficult to operate.

[0004] Therefore, it is crucial to solve the bottleneck problem of large pressure difference molten salt regulating valve and propose a structural design of angle-type large pressure difference molten salt regulating valve. Summary of the Invention

[0005] The purpose of the present invention is to provide an angle-type large pressure differential molten salt regulating valve to solve the problem of large pressure differential in existing molten salt regulating valves, which easily causes valve core vibration. The technical solution adopted by the present invention is as follows:

[0006] An angle-type large-pressure-differential molten salt regulating valve comprises a valve body, a valve stem, and a valve core. The valve body is provided with a valve cavity, through which the upper opening, lower opening, and side opening of the valve body are connected. The side opening of the valve body is a medium inlet, and the lower opening of the valve body is a medium outlet. A valve seat and a pressure-reducing and sound-reducing orifice plate are provided above and below the medium outlet. A pressure-reducing and sound-reducing orifice plate is provided in the medium inlet. The pressure-reducing and sound-reducing orifice plate is provided with a plurality of pressure-reducing holes. A valve cover seals the upper opening.

[0007] The throttling sleeve assembly includes a main valve sleeve, a four-stage valve sleeve, a three-stage valve sleeve, a two-stage valve sleeve and a first-stage valve sleeve, which are sequentially sleeved on the main valve sleeve from the inside to the outside, and a plurality of throttling flow holes are provided on the first-stage valve sleeve, and a plurality of throttling stepped holes are provided on the four-stage valve sleeve, the three-stage valve sleeve, the two-stage valve sleeve and the main valve sleeve, the throttling stepped hole is composed of a contraction hole section and an expansion hole section connected inside and outside, the diameter of the expansion hole section is larger than the diameter of the contraction hole section, the diameter of the contraction hole section is equal to the diameter of the throttling flow hole, a plurality of the throttling flow holes, a plurality of the throttling stepped holes on the two-stage valve sleeve, a plurality of the throttling stepped holes on the three-stage valve sleeve, a plurality of the throttling stepped holes on the four-stage valve sleeve and a plurality of the throttling stepped holes on the main valve sleeve are connected in sequence in a one-to-one correspondence, the lower side of the throttling flow hole is aligned with the lower side of the corresponding expansion hole section on the two-stage valve sleeve, and the lower sides of the contraction hole sections on the two-stage valve sleeve, the three-stage valve sleeve and the four-stage valve sleeve are all aligned with the lower side of the expansion hole section corresponding to the inner circumference;

[0008] The upper end of the main valve sleeve is connected to the valve cover, the inner periphery of the bottom of the main valve sleeve cooperates with the outer periphery of the valve seat, the first-level valve sleeve is located in the valve cavity, and a working space is provided between the outer periphery of the first-level valve sleeve and the side wall of the valve cavity. The outer periphery of the valve core slides with the inner periphery of the main valve sleeve to close or open several throttling stepped holes on the main valve sleeve. The top end of the inner periphery of the valve seat is provided with a first sealing cone surface, and the bottom end of the outer periphery of the valve core is provided with a second sealing cone surface. The first sealing cone surface and the second sealing cone surface are abutted against each other for sealing or separation. The lower end of the valve stem is connected to the valve core, and the upper end of the valve stem passes through the valve cover and slides and seals with the valve cover.

[0009] Furthermore, the inner hole of the valve seat is composed of a straight hole section and a tapered hole section connected up and down, and the valve seat is connected to the valve body by welding.

[0010] Furthermore, the main valve sleeve is welded and sealed to the valve cover.

[0011] Furthermore, the pressure-reducing silencer orifice plate includes an outer ring plate portion, a cone sleeve portion and a center circular plate portion. The small diameter end of the cone sleeve portion is connected to the outer periphery of the center circular plate portion, the large diameter end of the cone sleeve portion is connected to the inner periphery of the outer ring plate portion, the center circular plate portion is raised against the flow direction of the medium, the pressure-reducing holes on the outer ring plate portion are arranged perpendicular to the outer ring plate portion, the pressure-reducing holes on the cone sleeve portion are arranged perpendicular to the side wall of the cone sleeve portion, and the pressure-reducing holes on the center circular plate portion are arranged perpendicular to the center circular plate portion.

[0012] Furthermore, the lower end of the valve stem is provided with a frustum structure which gradually converges from bottom to top, and the axis of the valve core is provided with a conical hole structure which gradually converges from bottom to top. The frustum structure cooperates with the conical hole structure, and a clamping ring is threadedly sleeved on the valve stem. The valve cover and the clamping ring are connected by a conical pin, and the lower end face of the clamping ring is abutted against the upper end face of the valve core.

[0013] Furthermore, a heat-conducting column structure is provided on the upper end surface of the valve cover, and the valve stem passes through the valve cover via the heat-conducting column structure, and a heating device is wrapped around the heat-conducting column.

[0014] Furthermore, a stuffing box is processed on the upper end surface of the heat-conducting column structure, and the valve stem passes through the valve cover from the stuffing box. A stuffing assembly is provided in the stuffing box, and the stuffing cover is connected to the valve cover. The stuffing cover presses the stuffing assembly onto the bottom surface of the stuffing box through a pressing sleeve, and the valve cover and the valve stem are slidably sealed by the stuffing assembly.

[0015] Furthermore, the diameter of the expansion hole section is 2 to 3 times the diameter of the contraction hole section.

[0016] Furthermore, three annular grooves are processed on the upper part of the outer circle of the valve core, and metal piston rings are installed in the annular grooves. The valve core slides with the inner periphery of the main valve sleeve through the three metal piston rings, and several balance holes that are transparent from top to bottom are drilled on the valve core.

[0017] Furthermore, the valve cover and the valve body are sealed and connected by an octagonal gasket, and a concave stop is processed on the lower end surface of the main valve sleeve. The circumference of the concave stop cooperates with the outer circumference of the valve seat, and a gap is provided between the end surface of the concave stop and the upper end surface of the valve seat.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. There is enough space between the throttle sleeve assembly and the valve cavity so that the medium can evenly pass through the throttle sleeve assembly from the surrounding and reduce pressure. The pressure-reducing and muffler orifice at the medium inlet can take on part of the pressure-reducing task, thereby helping to reduce the vibration of the throttle sleeve assembly. The contraction hole section can reduce pressure and throttle the medium, and the expansion hole section can fully expand the medium. When the medium flows through the throttle sleeve assembly, it flows through the corresponding throttle flow hole, several throttle stepped holes on the secondary valve sleeve, several throttle stepped holes on the tertiary valve sleeve, several throttle stepped holes on the quaternary valve sleeve and several throttle stepped holes on the main valve sleeve in sequence, so that the medium is throttled once first. The pressure is reduced, and then it undergoes four times of expansion followed by throttling. The reduced pressure differential of the medium flowing through the throttling sleeve assembly is borne jointly by the main valve sleeve, the fourth-level valve sleeve, the third-level valve sleeve, the second-level valve sleeve and the first-level valve sleeve. Since the lower side of the throttling flow hole is aligned with the lower side of the expansion hole section corresponding to the second-level valve sleeve, the lower sides of the contraction hole sections on the second-level valve sleeve, the third-level valve sleeve and the fourth-level valve sleeve are all aligned with the lower side of the expansion hole section corresponding to the inner circumference. Compared with the prior art, when the medium flows through the throttling sleeve assembly, the flow direction of the medium is forced to be upward, the resistance that the medium needs to overcome is greater, and the energy consumed by the medium is greater, thereby better suppressing the vibration of the valve core and more significantly reducing the valve noise.

[0020] 2. The cone angle of the conical sleeve of the pressure-reducing and noise-reducing orifice plate is 120° to 160°, which is used to change the flow direction of the medium, effectively avoiding the impact force on the throttling sleeve assembly after the medium enters the valve body from the medium inlet, and can make the medium converge toward the center when flowing from the medium outlet to the valve body, thereby reducing the erosion of the medium on the inner wall of the pipeline and playing a role in protecting the pipeline. In the existing technology, the conical pressure-stabilizing and noise-reducing plate does not have pressure-reducing holes on the edge. After research, it was found that if all pressure-reducing holes are set perpendicular to the conical surface, when the medium flows through the conical pressure-stabilizing and noise-reducing plate, a significant vortex will be formed at the rear edge of the conical pressure-stabilizing and noise-reducing plate, causing the medium to rub and impact the valve body or the inner wall of the pipeline, aggravating the wear of the valve body or pipeline and generating noise. The medium streamlines at the outer edge of the pressure-reducing and silencer orifice plate of the present application are parallel to the pipeline, and the internal medium streamlines converge toward the center. By consuming the medium energy through interaction, the impact force of the medium on downstream parts can be reduced. Compared with the existing technology, the pressure-reducing and silencer orifice plate of the present invention can eliminate the vortex formed on the pressure-reducing side and extend the service life of the valve body.

[0021] 3. The valve cover and the valve body are connected by fastening bolts. Tightening the bolts can make the octagonal gasket play a sealing role to avoid medium leakage at the connection between the valve body and the valve cover. The compression of the octagonal gasket is not limited by other parts. When the medium temperature is high during the day and the temperature is low at night when it is shut down, the octagonal gasket fails in the temperature alternating environment. When the fastening bolts are further tightened, the octagonal gasket is further compressed and deformed. An assembly gap of 3mm to 4mm is reserved between the end face of the concave stop and the upper end face of the valve seat to provide space for the main valve sleeve to move downward.

[0022] 4. Since the lower side of the throttling hole is aligned with the lower side of the expansion hole section corresponding to the secondary valve sleeve, the lower sides of the contraction hole sections on the secondary valve sleeve, the third valve sleeve and the fourth valve sleeve are all aligned with the lower sides of the expansion hole sections corresponding to the inner circumference. The throttling hole is 1.5 mm lower than the corresponding contraction hole section on the main valve sleeve. The throttling hole to the throttling stepped hole on the corresponding main valve sleeve forms a stepped pressure-reducing structure, which allows the molten salt medium to be freely discharged from the throttling hole under the action of gravity when the unit is stopped, thereby avoiding valve blockage and failure caused by molten salt crystallization. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the present invention;

[0024] Figure 2 is a cross-sectional view of the throttle sleeve assembly;

[0025] Figure 3 yes Figure 1 A magnified view of point A;

[0026] Figure 4 It is a cross-sectional view of the pressure-reducing and muffler orifice plate;

[0027] Figure 5This is the medium streamline diagram of the simulation analysis of the existing conical voltage stabilizing and noise reducing plate;

[0028] Figure 6 This is a simulation analysis medium streamline diagram of the inlet pressure-reducing and silencer orifice plate of the present invention.

[0029] In the figure, 1. valve body, 2. pressure-reducing and silencer orifice plate, 21. center circular plate, 22. tapered sleeve, 23. outer ring plate, 24. pressure-reducing hole, 3. valve seat, 4. packing gland, 5. throttling sleeve assembly, 51. first-stage valve sleeve, 52. second-stage valve sleeve, 53. third-stage valve sleeve, 54. fourth-stage valve sleeve, 55. main valve sleeve, 56. throttling stepped hole, 6. valve core, 7. metal piston ring, 8. clamping ring, 9. tapered pin, 10. valve stem, 11. octagonal gasket, 12. heating device, 13. valve cover, 14. packing assembly. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions, and advantages of the present invention more clearly apparent, the present invention is described below using specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely illustrative and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0031] The connections mentioned in the present invention are divided into fixed connections and detachable connections. The fixed connection refers to a non-detachable connection, including but not limited to conventional fixed connection methods such as hem connection, rivet connection, adhesive connection, and welding connection. The detachable connection refers to but not limited to conventional detachable connection methods such as bolt connection, snap connection, pin connection, and hinge connection. When the specific connection method is not clearly specified, it is assumed that at least one connection method can be found among the existing connection methods to achieve the function. Those skilled in the art can choose according to their needs. For example, a welded connection is selected for a fixed connection, and a bolted connection is selected for a detachable connection.

[0032] The present invention will be further described in detail below with reference to the accompanying drawings. The following embodiments are provided to explain the present invention, but the present invention is not limited to the following embodiments.

[0033] Example: Figures 1 to 6 As shown, an angle-type large pressure difference molten salt regulating valve includes a valve body 1, a valve stem 10 and a valve core 6. The valve body 1 is provided with a valve cavity. The upper opening, lower opening and side opening of the valve body 1 are connected through the valve cavity. The side opening of the valve body 1 is a medium inlet, and the lower opening of the valve body 1 is a medium outlet. A valve seat 3 and a pressure-reducing and sound-reducing orifice plate 2 are provided above and below the diameter of the medium outlet. A pressure-reducing and sound-reducing orifice plate 2 is provided on the diameter of the medium inlet. The pressure-reducing and sound-reducing orifice plate 2 is provided with a plurality of pressure-reducing holes 24. The valve cover 13 closes the upper opening.

[0034] The throttle sleeve assembly 5 includes a main valve sleeve 55, a fourth-stage valve sleeve 54, a third-stage valve sleeve 53, a second-stage valve sleeve 52 and a first-stage valve sleeve 51 which are sleeved on the main valve sleeve 55 from the inside to the outside in sequence. The first-stage valve sleeve 51 is provided with a plurality of throttling flow holes, and the fourth-stage valve sleeve 54, the third-stage valve sleeve 53, the second-stage valve sleeve 52 and the main valve sleeve 55 are provided with a plurality of throttling stepped holes 56. The throttling stepped hole 56 is composed of a contraction hole section and an expansion hole section which are connected inside and outside. The diameter of the expansion hole section is larger than the diameter of the contraction hole section, and the diameter of the contraction hole section is the same as the diameter of the throttling hole section. The diameters of the flow holes are equal. The throttling flow holes, the throttling stepped holes 56 on the secondary valve sleeve 52, the throttling stepped holes 56 on the tertiary valve sleeve 53, the throttling stepped holes 56 on the quaternary valve sleeve 54, and the throttling stepped holes 56 on the main valve sleeve 55 are connected in sequence in a one-to-one correspondence. The lower side of the throttling flow hole is aligned with the lower side of the corresponding expansion hole section on the secondary valve sleeve 52. The lower sides of the contraction hole sections on the secondary valve sleeve 52, the tertiary valve sleeve 53, and the quaternary valve sleeve 54 are all aligned with the lower side of the corresponding expansion hole section on the inner circumference.

[0035] The upper end of the main valve sleeve 55 is connected to the valve cover 13, and the inner periphery of the bottom of the main valve sleeve 55 cooperates with the outer periphery of the valve seat 3. The first-level valve sleeve 51 is located in the valve cavity, and a working space is provided between the outer periphery of the first-level valve sleeve 51 and the side wall of the valve cavity. The outer periphery of the valve core 6 slides with the inner periphery of the main valve sleeve 55 to close or open the several throttling stepped holes 56 on the main valve sleeve 55. The top end of the inner periphery of the valve seat 3 is provided with a first sealing cone surface, and the bottom end of the outer periphery of the valve core 6 is provided with a second sealing cone surface. The first sealing cone surface and the second sealing cone surface are abutted against each other for sealing or separation. The lower end of the valve stem 10 is connected to the valve core 6, and the upper end of the valve stem 10 passes through the valve cover 13 and slides and seals with the valve cover 13. The actuator is mounted on the valve cover 13 through a bracket, and the upper end of the valve stem 10 is threadedly connected to the output end of the actuator.

[0036] There is enough space between the throttling sleeve assembly 5 and the valve cavity, so that the medium can evenly pass through the throttling sleeve assembly 5 from the surrounding and be decompressed. The pressure-reducing and muffler orifice 2 at the medium inlet can undertake part of the pressure reduction task, thereby helping to reduce the vibration of the throttling sleeve assembly 5. The contraction hole section can decompress and throttle the medium, and the expansion hole section can fully expand the medium. When the medium flows through the throttling sleeve assembly 5, it flows through the corresponding throttling flow hole, the several throttling stepped holes 56 on the secondary valve sleeve 52, the several throttling stepped holes 56 on the third valve sleeve 53, the several throttling stepped holes 56 on the fourth valve sleeve 54 and the several throttling stepped holes 56 on the main valve sleeve 55 in sequence, so that the medium is first throttled and reduced in pressure. The pressure is then expanded and then throttled four times. The pressure difference of the medium flowing through the throttling sleeve assembly 5 is borne jointly by the main valve sleeve 55, the fourth-level valve sleeve 54, the third-level valve sleeve 53, the second-level valve sleeve 52 and the first-level valve sleeve 51. Since the lower side of the throttling flow hole is aligned with the lower side of the expansion hole section corresponding to the second-level valve sleeve 52, the lower sides of the contraction hole sections on the second-level valve sleeve 52, the third-level valve sleeve 53 and the fourth-level valve sleeve 54 are all aligned with the lower side of the expansion hole section corresponding to the inner circumference. Compared with the prior art, when the medium flows through the throttling sleeve assembly 5, the flow direction of the medium is forced to be upward, the resistance that the medium needs to overcome is greater, and the energy consumed by the medium is greater, thereby better suppressing the vibration of the valve core 6 and more significantly reducing the valve noise.

[0037] The operating environment of the present invention is as follows: when the unit is running during the day, the temperature of the molten salt medium flowing through the present invention is about 575° C., and the unit stops running at night.

[0038] Since the lower side of the throttling hole is aligned with the lower side of the expansion hole section corresponding to the secondary valve sleeve 52, the lower sides of the contraction hole sections on the secondary valve sleeve 52, the tertiary valve sleeve 53 and the quaternary valve sleeve 54 are all aligned with the lower side of the expansion hole section corresponding to the inner periphery, the throttling hole is 1.5 mm lower than the corresponding contraction hole section on the main valve sleeve 55, and a pressure-reducing structure is formed from the throttling hole to the throttling stepped hole 56 on the corresponding main valve sleeve 55, which can enable the molten salt medium to be freely discharged from the throttling hole under the action of gravity when the unit is stopped, thereby avoiding valve blockage and failure caused by crystallization of the molten salt; when the opening is below 20%, the throttling holes are small and evenly distributed, and when the opening is above 20%, the aperture is large and evenly distributed, so that the valve adjustment characteristics are corrected linear, the adjustable ratio of the valve is increased, and high-precision adjustment can be achieved under both minimum and maximum operating conditions.

[0039] The inner hole of the valve seat 3 is composed of a straight hole section and a tapered hole section connected up and down, so that the outlet medium slowly expands and gradually reduces the medium flow rate, avoiding valve vibration caused by high flow rate. The valve seat 3 is welded to the valve body 1, reducing internal leakage points and improving sealing performance.

[0040] The main valve sleeve 55 is welded and sealed to the valve cover 13 to reduce leakage points between the throttle sleeve assembly 5 and the valve core 6.

[0041] The pressure-reducing and muffler orifice plate 2 comprises an outer ring plate portion 23, a tapered sleeve portion 22, and a central circular plate portion 21. The smaller diameter end of the tapered sleeve portion 22 is connected to the outer periphery of the central circular plate portion 21, while the larger diameter end of the tapered sleeve portion 22 is connected to the inner periphery of the outer ring plate portion 23. The central circular plate portion 21 is raised against the direction of the medium flow. The pressure-reducing holes 24 on the outer ring plate portion 23 are perpendicular to the outer ring plate portion 23, the pressure-reducing holes 24 on the tapered sleeve portion 22 are perpendicular to the sidewall of the tapered sleeve portion 22, and the pressure-reducing holes 24 on the central circular plate portion 21 are perpendicular to the central circular plate portion 21. The tapered sleeve portion 22 has a taper angle of 120° to 160°, which is used to change the direction of medium flow, effectively preventing the impact of the medium on the throttling sleeve assembly 5 after entering the valve body 1 from the medium inlet. It also allows the medium to converge toward the center as it flows from the medium outlet to the valve body 1, thereby reducing the impact of the medium on the inner wall of the pipeline and protecting the pipeline. In the prior art, for example, Chinese invention patent publication number CN 116006767A discloses a novel multi-stage adjustable step-down regulating valve and a conical pressure-stabilizing and noise-reducing plate. Compared with the pressure-reducing and muffler hole plate 2 of the present application, the conical pressure-stabilizing and noise-reducing plate differs in that the conical pressure-stabilizing and noise-reducing plate does not have pressure-reducing holes 24 on its edge. Research has shown that if all pressure-reducing holes 24 are arranged perpendicular to the conical surface, when the medium flows through the conical pressure-stabilizing and noise-reducing plate, a significant vortex will be formed at the rear edge of the conical pressure-stabilizing and noise-reducing plate. Figure 5 The medium streamlines extracted through simulation analysis are given. It can be seen that obvious vortices are formed at the rear edge of the conical pressure-stabilizing and noise-reducing plate, causing the medium to rub and impact the inner wall of the valve body 1, aggravating the wear of the pipeline and generating noise. Figure 6 The medium streamline diagram extracted from the pressure-reducing and silencer orifice plate 2 of the present application through simulation analysis is given. It can be seen that the medium streamlines at the outer edge are parallel to the pipeline, and the internal medium streamlines converge toward the center. The medium energy is consumed through interaction, which can reduce the impact force of the medium on downstream parts. Compared with the prior art, the pressure-reducing and silencer orifice plate 2 in the present invention can eliminate the vortex formed on the pressure-reducing side and extend the service life of the valve body 1.

[0042] The lower end of the valve stem 10 is provided with a frustum structure that gradually converges from bottom to top, and the axis of the valve core 6 is provided with a conical hole structure that gradually converges from bottom to top. The frustum structure cooperates with the conical hole structure. A clamping ring 8 is threadedly sleeved on the valve stem 10, and the valve cover 13 and the clamping ring 8 are pin-connected by a tapered pin 9. The lower end surface of the clamping ring 8 is abutted against the upper end surface of the valve core 6.

[0043] The upper end surface of the valve cover 13 is provided with a heat-conducting column structure, through which the valve stem 10 passes. The heat-conducting column is wrapped with a heat tracing device 12. The upper end surface of the heat tracing device 12 is slightly higher than the lower end of the packing assembly 14 to prevent the molten salt medium from crystallizing and affecting the sealing performance of the packing assembly 14.

[0044] A stuffing box is machined on the upper end surface of the heat-conducting column structure. The valve stem 10 passes through the valve cover 13 through the stuffing box. A packing assembly 14 is installed in the stuffing box. The packing gland 4 is connected to the valve cover 13. The packing gland 4 presses the packing assembly 14 against the bottom surface of the stuffing box through a compression sleeve. The valve cover 13 and the valve stem 10 are slidably sealed by the packing assembly 14. The packing assembly 14 is a packing assembly specially designed for molten salt and can effectively prevent the leakage of the medium.

[0045] The diameter of the expansion hole section is 2 to 3 times the diameter of the contraction hole section.

[0046] Three annular grooves are machined into the upper outer circumference of the valve core 6, and metal piston rings 7 are installed in these annular grooves. The valve core 6 slides with the inner circumference of the main valve sleeve 55 through the three metal piston rings 7, so that the valve core 6 is guided throughout its entire stroke, avoiding both sticking and vibration of the valve core 6. Several vertically transparent balancing holes are drilled in the valve core 6 to connect the valve cavities on the upper and lower sides of the valve core 6, thereby preventing unbalanced force on the valve core 6.

[0047] The valve cover 13 and valve body 1 are sealed together via an octagonal gasket 11. A recessed stopper is machined into the lower end surface of the main valve sleeve 55. The circumference of the recessed stopper slides with the outer periphery of the valve seat 3, with a gap provided between the end surface of the recessed stopper and the upper end surface of the valve seat 3. The valve cover 13 and valve body 1 are connected via fastening bolts. Tightening the bolts seals the octagonal gasket 11, preventing leakage of media at the connection between the valve body 1 and the valve cover 13. The compression of the octagonal gasket 11 is not limited by other components. If the octagonal gasket 11 fails due to the alternating temperature environment of high daytime media temperatures and low nighttime temperatures during shutdown, further tightening of the fastening bolts can cause further compression and deformation of the octagonal gasket 11. A 3mm to 4mm assembly gap is reserved between the end surface of the recessed stopper and the upper end surface of the valve seat 3, providing space for the main valve sleeve 55 to move downward.

[0048] The above embodiments are merely illustrative of the present invention and do not limit its scope of protection. Those skilled in the art may make partial changes thereto, which are within the scope of protection of the present invention as long as they do not exceed the spirit of the present invention.

Claims

1. An angle-type large pressure difference molten salt regulating valve, comprising a valve body (1), a valve stem (10) and a valve core (6), characterized in that: The valve body (1) is provided with a valve cavity, and the upper opening, lower opening and side opening of the valve body (1) are connected through the valve cavity. The side opening of the valve body (1) is a medium inlet, and the lower opening of the valve body (1) is a medium outlet. A valve seat (3) and a pressure-reducing and sound-reducing orifice plate (2) are provided above and below the diameter of the medium outlet. A pressure-reducing and sound-reducing orifice plate (2) is provided in the diameter of the medium inlet, and a plurality of pressure-reducing holes (24) are provided on the pressure-reducing and sound-reducing orifice plate (2). The valve cover (13) closes the upper opening. The throttling sleeve assembly (5) includes a main valve sleeve (55), a fourth-stage valve sleeve (54), a third-stage valve sleeve (53), a second-stage valve sleeve (52) and a first-stage valve sleeve (51) which are sequentially sleeved on the main valve sleeve (55) from the inside to the outside. The first-stage valve sleeve (51) is provided with a plurality of throttling flow holes. The fourth-stage valve sleeve (54), the third-stage valve sleeve (53), the second-stage valve sleeve (52) and the main valve sleeve (55) are all provided with a plurality of throttling stepped holes (56). The throttling stepped holes (56) are composed of a contraction hole section and an expansion hole section which are connected inside and outside. The diameter of the expansion hole section is larger than the diameter of the contraction hole section. The diameter of the contraction hole section is the same as that of the first-stage valve sleeve (51). The throttling holes have the same diameter, and the throttling holes, the throttling stepped holes (56) on the secondary valve sleeve (52), the throttling stepped holes (56) on the tertiary valve sleeve (53), the throttling stepped holes (56) on the quaternary valve sleeve (54), and the throttling stepped holes (56) on the main valve sleeve (55) are connected in sequence one by one, and the lower side of the throttling holes is aligned with the lower side of the corresponding expansion hole section on the secondary valve sleeve (52), and the lower sides of the contraction hole sections on the secondary valve sleeve (52), the tertiary valve sleeve (53), and the quaternary valve sleeve (54) are all aligned with the lower side of the corresponding expansion hole section on the inner circumference; The upper end of the main valve sleeve (55) is connected to the valve cover (13), the inner periphery of the bottom of the main valve sleeve (55) cooperates with the outer periphery of the valve seat (3), the first-level valve sleeve (51) is located in the valve cavity, and a working space is provided between the outer periphery of the first-level valve sleeve (51) and the side wall of the valve cavity. The outer periphery of the valve core (6) slides with the inner periphery of the main valve sleeve (55) to close or open a plurality of throttling stepped holes (56) on the main valve sleeve (55). The top end of the inner periphery of the valve seat (3) is provided with a first sealing cone surface, and the bottom end of the outer periphery of the valve core (6) is provided with a second sealing cone surface. The first sealing cone surface and the second sealing cone surface are abutted against each other for sealing or separation. The lower end of the valve stem (10) is connected to the valve core (6), and the upper end of the valve stem (10) passes through the valve cover (13) and slides and seals with the valve cover (13).

2. The angular large pressure difference molten salt regulating valve according to claim 1, characterized in that: The inner hole of the valve seat (3) is composed of a straight hole section and a tapered hole section connected up and down, and the valve seat (3) is connected to the valve body (1) by welding.

3. The angular large pressure difference molten salt regulating valve according to claim 1, characterized in that: The main valve sleeve (55) is connected to the valve cover (13) by welding and sealing.

4. The angular large pressure difference molten salt regulating valve according to claim 1, characterized in that: The pressure-reducing sound-absorbing orifice plate (2) comprises an outer ring plate portion (23), a cone sleeve portion (22) and a center circular plate portion (21); the small-diameter end of the cone sleeve portion (22) is connected to the outer periphery of the center circular plate portion (21); the large-diameter end of the cone sleeve portion (22) is connected to the inner periphery of the outer ring plate portion (23); the center circular plate portion (21) is raised in the opposite direction of the medium flow; the pressure-reducing hole (24) on the outer ring plate portion (23) is arranged perpendicular to the outer ring plate portion (23); the pressure-reducing hole (24) on the cone sleeve portion (22) is arranged perpendicular to the side wall of the cone sleeve portion (22); and the pressure-reducing hole (24) on the center circular plate portion (21) is arranged perpendicular to the center circular plate portion (21).

5. The angular large pressure difference molten salt regulating valve according to claim 1, characterized in that: The lower end of the valve stem (10) is provided with a cone structure that gradually converges from bottom to top, and the axis of the valve core (6) is provided with a cone hole structure that gradually converges from bottom to top. The cone structure and the cone hole structure cooperate with each other. A clamping ring (8) is threadedly sleeved on the valve stem (10), and the valve cover (13) and the clamping ring (8) are connected by a tapered pin (9). The lower end face of the clamping ring (8) is in contact with the upper end face of the valve core (6).

6. The angle-type large pressure difference molten salt regulating valve according to claim 1, characterized in that: A heat-conducting column structure is provided on the upper end surface of the valve cover (13), and the valve stem (10) passes through the valve cover (13) through the heat-conducting column structure. A heating device (12) is wound around the heat-conducting column.

7. The angle-type large pressure difference molten salt regulating valve according to claim 6, characterized in that: A stuffing box is machined on the upper end surface of the heat-conducting column structure, and the valve stem (10) passes through the valve cover (13) from the stuffing box. A stuffing assembly (14) is provided in the stuffing box. The stuffing gland (4) is connected to the valve cover (13). The stuffing gland (4) presses the stuffing assembly (14) onto the bottom surface of the stuffing box through a pressing sleeve. The valve cover (13) and the valve stem (10) are slidably sealed through the stuffing assembly (14).

8. The angle-type large pressure difference molten salt regulating valve according to claim 1, characterized in that: The diameter of the expansion hole section is 2 to 3 times the diameter of the contraction hole section.

9. The angle-type large pressure difference molten salt regulating valve according to claim 1, characterized in that: Three annular grooves are machined on the outer circle upper part of the valve core (6), and metal piston rings (7) are installed in the annular grooves. The valve core (6) is slidably matched with the inner circumference of the main valve sleeve (55) through the three metal piston rings (7). A plurality of balance holes that are transparent from top to bottom are drilled on the valve core (6).

10. An angular large pressure difference molten salt regulating valve according to any one of claims 1 to 9, characterized in that: The valve cover (13) and the valve body (1) are sealed and connected via an octagonal gasket (11). A concave stop is machined on the lower end surface of the main valve sleeve (55). The circumference of the concave stop is matched with the outer circumference of the valve seat (3). A gap is provided between the end surface of the concave stop and the upper end surface of the valve seat (3).

Images