CN113464715B

CN113464715B - Three-stage pressure reducing cage sleeve type throttle valve

Info

Publication number: CN113464715B
Application number: CN202110819561.4A
Authority: CN
Inventors: 周群; 余波; 聂涛; 刘成; 胡贵川; 李显勇
Original assignee: Chongqing University of Science and Technology
Current assignee: Chongqing University of Science and Technology
Priority date: 2021-07-20
Filing date: 2021-07-20
Publication date: 2022-09-02
Anticipated expiration: 2041-07-20
Also published as: CN113464715A

Abstract

The invention discloses a three-stage pressure reducing cage type throttle valve which comprises a valve body and a valve cover arranged on the valve body, wherein a valve rod is arranged on the valve cover through a first mounting hole, a hand wheel is arranged at the upper end of the valve rod, an inlet flow passage and an outlet flow passage are formed in the valve body, a throttle valve core is arranged between the inlet flow passage and the outlet flow passage, the throttle valve core comprises a first-stage cage sleeve, a second-stage cage sleeve and a third-stage cage sleeve which are coaxially nested from outside to inside, a first-stage throttle hole, a second-stage throttle hole and a third-stage throttle hole are respectively formed in the side walls of the first-stage cage sleeve, the second-stage cage sleeve and the third-stage cage sleeve, the number of the third-stage throttle holes is 3, 2, 5, 4, 1 and 6 in sequence on the cylindrical surface of the third-stage cage sleeve, and the lower end of the valve rod extends into the third-stage cage sleeve through a second mounting hole formed in the valve body. The invention aims to provide a three-stage pressure reducing cage sleeve type throttle valve which can reduce the operation cost by improving the pressure drop range.

Description

Three-stage decompression cage sleeve type throttle valve

Technical Field

The invention relates to the technical field of throttle valves, in particular to a three-stage decompression cage sleeve type throttle valve.

Background

The throttle valve is widely applied to various industries at home and abroad, and particularly plays a significant role in hydraulic engineering, transportation engineering, petroleum engineering, chemical industry and the like. In some oil production wells of oil fields, natural gas transportation pipelines, sewage treatment and drainage projects and the like, throttle valves are required to complete corresponding throttling. Because of this, the quality of the throttle valve performance has a significant influence on the oil and gas extraction efficiency and safety. The main flow throttle valves can be divided into needle valves, wedge valves, cage valves, plate valves and the like according to the structure, and can be divided into single-stage throttle valves and double-stage throttle valves according to the arrangement number of the throttle elements.

Taking the most common two-stage cage type throttle valve in the market as an example, the traditional two-stage cage type throttle valve is a throttle valve which is formed by coaxially nesting two cages with small holes, and takes the two cages as two throttling elements. The double-layer cage type throttle valve mainly comprises a valve cover, a packing box, a sleeve, a cage assembly (comprising a first layer of cage and a second layer of cage), a valve body and a valve sleeve assembly. The sleeve is used for fixing the first layer of cage. The valve sleeve is positioned between the first layer of cage sleeve and the second layer of cage sleeve, and the two layers of cage sleeves share one valve sleeve. The valve sleeve can move between the two layers of cage sleeves, the opening of the throttle valve is changed, and the function of adjusting the technological parameters is realized, however, the structure at least has the following two problems:

when the medium pressure is very high, the medium backflow has very high impact force on the internal structure of the two-stage throttle valve, so that the outlet flow is too small, the phenomenon of blockage is easy to occur, and the medium transmission efficiency is influenced;

secondly, the pressure drop of the two-stage throttle valve is larger, which means that the valve core needs to bear medium impact to a larger degree, so that the first layer of cage sleeve and the second layer of cage sleeve are seriously abraded and eroded, and the service life of the throttle valve is shortened.

Disclosure of Invention

The invention aims to provide a three-stage decompression cage sleeve type throttle valve which can reduce the operation cost by improving the pressure drop range and aims to solve the technical problems explained in the background technology.

In order to achieve the above purpose, the invention firstly provides a three-stage pressure reducing cage type throttle valve, which comprises a valve body and a valve cover arranged on the valve body, wherein a valve rod is arranged on the valve cover through a first mounting port, a hand wheel is arranged at the upper end of the valve rod, the key point is that an inlet flow passage and an outlet flow passage are arranged on the valve body, a throttle valve core is arranged between the inlet flow passage and the outlet flow passage, the throttle valve core comprises a first-stage cage sleeve, a second-stage cage sleeve and a third-stage cage sleeve which are coaxially nested from outside to inside, a first-stage throttle hole, a second-stage throttle hole and a third-stage throttle hole are respectively arranged on the side walls of the first-stage cage sleeve, the second-stage cage sleeve and the third-stage cage sleeve, the three-stage throttle holes are sequentially arranged on the cylindrical surface of the third-stage cage sleeve in a row by 3, 2, 5, 4, 1 and 6, and the lower end of the valve rod extends into the third-stage cage sleeve through a second mounting port arranged on the valve body, and the opening degree of the throttling valve core is adjusted by matching with the three-level throttling hole.

Furthermore, a valve rod nut which is sleeved with the valve rod is arranged in the first mounting opening, and a locking nut is further sleeved on the valve rod at the upper end of the valve rod nut.

Furthermore, a packing seat is arranged in the second mounting port, the packing seat is sleeved with the valve rod through a packing gland, and a plurality of O-shaped sealing rings are hermetically connected between the inner wall of the second mounting port and the packing seat.

Furthermore, the primary throttle holes and the secondary throttle holes are uniformly distributed in multiple rows around the axial lead of the tertiary cage sleeve respectively.

Furthermore, the included angle of the axial leads of two adjacent primary orifices at the same height is 60 DEG

Furthermore, the axial lead angle of two adjacent secondary orifices at the same height is 60 degrees.

Further, the number of each row of primary orifices and each row of secondary orifices is 6.

Further, the primary orifice and the secondary orifice of the same height are offset.

Furthermore, the primary throttle hole is communicated with the inlet flow channel, the lower end of the tertiary cage sleeve is also provided with a throttle seat, and the throttle seat is provided with a plurality of four-stage throttle holes communicated with the outlet flow channel.

Compared with the prior art, the invention has the remarkable effects that:

(1) compared with the traditional single-stage or double-stage throttle valve, the three-stage cage sleeve type throttle valve core is utilized, the range of pressure drop is enlarged, the number of throttle valves used in the operation process can be reduced, and the operation cost is greatly reduced;

(2) the specially arranged three-level throttling holes are utilized, the pressure drop range is further enlarged, the operation cost is reduced, and the method is particularly suitable for ultrahigh-pressure operation scenes; meanwhile, under the action of the three-level throttling hole, the speed of the medium is changed very uniformly, so that the medium speed and the opening degree of the three-level cage sleeve are ensured to be in a substantially proportional relation;

(3) the flowing direction of the medium can be changed for many times through the primary throttling hole and the secondary throttling hole which are distributed in a staggered manner, the front and back throttling pressure difference is increased by a certain amount in a cavity formed between two adjacent layers of cage sleeves, and finally the total pressure drop ratio is increased by one grade;

(4) the throttling seat is added on the outlet flow passage, so that the position of stress concentration in the operation process of the throttling valve is changed, and the position of the cage sleeve is transferred to the throttling seat, thereby reducing the abrasion of a throttling element in the valve core and prolonging the service life of the throttling valve;

(5) the throttle seat is arranged at the lower end of the three-level cage sleeve, so that the throttle seat is convenient to replace, the maintenance period is shortened, and the maintenance cost is obviously reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic overall structure diagram of the first embodiment;

FIG. 2 is a perspective view of a throttle body in accordance with a first embodiment;

FIG. 3 is a half sectional view of a throttle body in accordance with a first embodiment;

FIG. 4 is an axial cross-sectional view of a throttle valve cartridge of an embodiment;

FIG. 5 is a distribution diagram of tertiary orifices after cylindrical deployment of a tertiary cage in accordance with one embodiment;

FIG. 6 is a schematic diagram showing the change of the valve core opening degree and the medium pressure in the first embodiment;

FIG. 7 is a schematic diagram illustrating the variation of the valve spool opening and the fluid velocity according to one embodiment;

reference numbers in the figures: the four-stage throttling valve comprises a valve body 1, a valve cover 2, a valve rod 3, a hand wheel 4, an inlet runner 5, an outlet runner 6, a throttling valve core 7, a primary cage sleeve 8, a secondary cage sleeve 9, a tertiary cage sleeve 10, a primary throttling hole 11, a secondary throttling hole 12, a tertiary throttling hole 13, a valve rod nut 14, a locking nut 15, a packing seat 16, a packing gland 17, an O-shaped sealing ring 18, a throttling seat 19 and a throttling hole 20.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. In addition, in the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

Fig. 1 to 3 show a first exemplary embodiment of the invention: a three-level pressure reduction cage type throttle valve comprises a valve body 1 and a valve cover 2 arranged on the valve body 1, wherein a valve rod 3 is installed on the valve cover 2 through a first installation opening, a hand wheel 4 is arranged at the upper end of the valve rod 3, the key point is that an inlet flow passage 5 and an outlet flow passage 6 are arranged on the valve body 1, a throttle valve core 7 is arranged between the inlet flow passage 5 and the outlet flow passage 6, the throttle valve core 7 comprises a first-level cage sleeve 8, a second-level cage sleeve 9 and a third-level cage sleeve 10 which are coaxially nested from outside to inside, a first-level throttle hole 11, a second-level throttle hole 12 and a third-level throttle hole 13 are respectively arranged on the side walls of the first-level cage sleeve 8, the second-level cage sleeve 9 and the third-level cage sleeve 10, the third-level throttle hole 13 is sequentially provided with 3, 2, 5, 4, 1 and 6 on the cylindrical surface of the third-level cage sleeve 10, and the lower end of the valve rod 3 extends into the tertiary cage 10 through a second mounting port formed in the valve body 1 and is matched with the tertiary throttle hole 13 to realize the opening adjustment of the throttle valve core 7.

As shown in fig. 1, in specific implementation, a valve stem nut 14 sleeved with the valve stem 3 is arranged in the first mounting port, and a lock nut 15 is further sleeved on the valve stem 3 at the upper end of the valve stem nut 14. A packing seat 16 is arranged in the second mounting port, the packing seat 16 is sleeved with the valve rod 3 through a packing gland 17, and a plurality of O-shaped sealing rings 18 are hermetically connected between the inner wall of the second mounting port and the packing seat 16.

As shown in fig. 3, in order to optimize the circulation path of the medium in the throttle body 7, a plurality of rows of primary orifices 11 and secondary orifices 12 are uniformly arranged around the axial center line of the tertiary cage 10. The axial lead included angle of two adjacent primary throttle holes 11 at the same height is 60 degrees. The axial lead included angle of two adjacent secondary throttle holes 12 at the same height is 60 degrees. The primary throttle holes 11 and the secondary throttle holes 12 at the same height are arranged in a staggered manner.

Referring to fig. 5, the three-stage orifices 13 are preferably arranged in six rows, and the number of the three-stage orifices 13 in the six rows of the three-stage orifices 13 is preferably 3, 2, 5, 4, 1, and 6.

In the present embodiment, the same point (0.005 m plane center point from the base orifice) inside the throttle valve body 7 is designated for the throttle valve body 7 which normally operates at different opening degrees, and the internal static pressure and the opening degree change as shown in fig. 6. The throttle area is increased along with the increase of the opening degree, the pressure at the outlet is slowly reduced, and the pressure drop is relatively gentle after the opening degree is 42 mm. For different flow rates of the medium, the larger the flow rate, the larger the corresponding pressure.

Fig. 7 shows the relationship between the opening degree and the speed, and it can be seen from the graph that the larger the opening degree is, the larger the flow rate is, and the larger the flow rate of the gas passing through per unit time is, and the larger the speed is. However, since the three-stage orifices on the three-stage cage 105 are distributed as shown in fig. 5, the speed change is very uniform, and as can be seen from fig. 7, the speed and the opening degree are in a substantially proportional relationship, so that the layout of the three-stage orifices 13 is also verified.

As shown in fig. 3 and 4, in order to change the stress concentration range and reduce the wear on the throttle valve core 7, the primary throttle hole 11 is communicated with the inlet flow passage 5, the lower end of the tertiary cage 10 is further provided with a throttle seat 19, and the throttle seat 19 is provided with a plurality of four-stage throttle holes 20 communicated with the outlet flow passage 6.

In conclusion, compared with the traditional single-stage or double-stage throttle valve, the throttle valve core 7 with the three-stage cage 10 type is utilized, so that the pressure drop range is enlarged, the number of the throttle valves used in the operation process can be reduced, and the operation cost is greatly reduced; the three-level throttling hole 13 which is specially arranged is utilized, the pressure drop range is further improved, the operation cost is reduced, and the method is particularly suitable for ultrahigh pressure operation scenes; meanwhile, under the action of the three-level throttling hole 13, the medium speed changes very uniformly, so that the medium speed is ensured to be in a substantially direct proportion relation with the opening degree of the three-level cage 10; the flowing direction of the medium can be changed for many times through the primary throttle holes 11 and the secondary throttle holes 12 which are distributed in a staggered manner, the front-back throttle pressure difference is increased by a certain amount in a cavity formed between two adjacent layers of cages, and finally the total pressure drop ratio is increased by one grade; by adding the throttle seat 19 on the outlet flow passage 6, the position of stress concentration in the operation process of the throttle valve is changed, and the stress concentration position is transferred to the throttle seat 19 from the position of the cage sleeve, so that the abrasion of a throttle element in the valve core is reduced, and the service life of the throttle valve is prolonged; the throttle seat 19 is arranged at the lower end of the three-stage cage 10, so that the replacement is convenient, the maintenance period is shortened, and the maintenance cost is obviously reduced.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims

1. A three-level pressure reduction cage type throttle valve comprises a valve body and a valve cover arranged on the valve body, wherein a valve rod is arranged on the valve cover through a first mounting port, a hand wheel is arranged at the upper end of the valve rod, the throttle valve is characterized in that an inlet flow passage and an outlet flow passage are arranged on the valve body, a throttle valve core is arranged between the inlet flow passage and the outlet flow passage, the throttle valve core comprises a first-level cage sleeve, a second-level cage sleeve and a third-level cage sleeve which are coaxially nested from outside to inside, a first-level throttling hole, a second-level throttling hole and a third-level throttling hole are respectively arranged on the side walls of the first-level cage sleeve, the second-level cage sleeve and the third-level cage sleeve, the number of the third-level throttling holes is 3, 2, 5, 4, 1 and 6 in sequence on the cylindrical surface of the third-level cage sleeve, and the lower end of the valve rod extends into the third-level cage sleeve through a second mounting port arranged on the valve body, and the opening degree of the throttling valve core is adjusted by matching with the three-level throttling hole.

2. The three-stage pressure reduction cage type throttle valve according to claim 1, wherein a valve stem nut is disposed in the first mounting opening and is sleeved with the valve stem, and a locking nut is further sleeved on the valve stem at the upper end of the valve stem nut.

3. The three-stage pressure reduction cage-type throttle valve according to claim 2, wherein a packing seat is arranged in the second mounting port, the packing seat is sleeved with the valve rod through a packing gland, and a plurality of O-ring seals are further connected between the inner wall of the second mounting port and the packing seat in a sealing manner.

4. The three-stage pressure reduction cage type throttle valve according to any one of claims 1 to 3, wherein the primary throttle holes and the secondary throttle holes are respectively and uniformly arranged in a plurality of rows around the axial lead of the three-stage cage.

5. The three-stage pressure reducing cage-type throttling valve according to claim 4, wherein the axial lead angle of two adjacent primary throttling holes at the same height is 60 degrees.

6. The three-stage pressure reducing cage-type throttle valve according to claim 5, wherein the axial lead angle between two adjacent two secondary orifices at the same height is 60 °.

7. The three-stage pressure reducing cage-type throttle valve according to claim 6, wherein the number of each row of primary orifices and each row of secondary orifices is 6.

8. The three-stage pressure reducing cage-type throttle valve according to claim 7, wherein the primary throttle hole and the secondary throttle hole at the same height are distributed with a dislocation.

9. The three-stage pressure reducing cage type throttle valve according to claim 1, wherein the primary throttle hole is communicated with the inlet flow passage, the lower end of the three-stage cage is further provided with a throttle seat, and the throttle seat is provided with a plurality of four-stage throttle holes communicated with the outlet flow passage.