Cage sleeve type pressure reducing throttle valve

Abstract

The cage sleeve type pressure reducing throttle valve comprises a valve body, a valve cover, a valve seat and a valve rod, a fluid inlet hole and a fluid outlet hole are formed in the valve body, a valve element is arranged between the fluid inlet hole and the fluid outlet hole, and the valve element comprises a third-level cage sleeve, a second-level cage sleeve, a first-level cage sleeve and an outer cage sleeve which are sequentially and fixedly connected from inside to outside; the valve seat is connected with the bottom end of the inner side wall of the third-stage cage sleeve in a sealed mode, gradually-changing through holes are formed in the side walls of the third-stage cage sleeve, the second-stage cage sleeve and the first-stage cage sleeve, the sizes of the gradually-changing through holes are gradually changed in the thickness direction of the cage sleeves, and the bottom of the valve rod is inserted into the third-stage cage sleeve and can slide up and down relative to the third-stage cage sleeve so that the opening degree of the cage sleeves can be adjusted. According to the cage sleeve type pressure reduction throttling valve, the pressure drop range of the throttling valve can be widened, simultaneous pressure reduction through a plurality of throttling valves is avoided, meanwhile, the flow control capacity of the throttling valve is improved, potential safety hazards of the throttling valve are reduced, and the operation cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas engineering, and particularly relates to a cage sleeve type pressure reducing throttle valve. BACKGROUND

[0002] The throttle valve is a basic equipment for oil and gas exploitation. The wellhead of natural gas often has high pressure, and the pressure that some oil wells and natural gas gathering pipelines can withstand is limited. Therefore, it is necessary to throttle and reduce the pressure of natural gas at the wellhead. At present, various types of throttle and pressure reducing valves are used at the wellhead of natural gas. The mainstream throttle valves can be divided into needle valves, wedge valves, cage sleeve valves and flat plate valves according to the structure. The cage sleeve throttle valve is widely used in oil and gas fields due to its good pressure drop and flow control capacity.

[0003] At present, the most common cage sleeve throttle valve on the market is a single-layer or double-layer cage sleeve, that is, there is only one or two layers of throttle holes arranged in a certain order on the cage sleeve. The number of throttle holes is changed by moving the valve stem up and down in the cage sleeve to realize pressure and flow regulation. However, the throttling effect of the single-layer and double-layer cage sleeve is limited, and the cage sleeve and valve core are easily eroded and damaged after being impacted by high-speed gas. According to statistics, in order to adapt to the harsh conditions of high-pressure gas fields, the cage sleeve throttle valves produced by foreign well-known companies are used in natural gas exploitation and transportation pipelines in China at present. The price is expensive, but in actual use, different degrees of cage sleeve erosion and erosion failure occur without exception. The cage sleeve is replaced every 2 months on average, the service life of the cage sleeve is short, and the production efficiency is seriously affected. And in a wide range of pressure reduction, multiple throttle valves are often used to work, which greatly prolongs the working time. SUMMARY

[0004] The main purpose of the present application is to provide a cage sleeve type pressure reducing throttle valve, which aims to improve the pressure drop range and reduce the operation cost.

[0005] In order to achieve the above purpose, the present application provides a cage sleeve type pressure reducing throttle valve, which comprises a valve body, a valve cover, a valve seat and a valve stem. The valve body is provided with a fluid inlet hole and a fluid outlet hole. The valve core is arranged between the fluid inlet hole and the fluid outlet hole. The valve core comprises a three-stage cage sleeve, a two-stage cage sleeve, a one-stage cage sleeve and an outer cage sleeve which are fixedly connected in sequence from inside to outside. The valve seat is sealingly connected with the inner side wall bottom end of the three-stage cage sleeve. The side walls of the three-stage cage sleeve, the two-stage cage sleeve and the one-stage cage sleeve are all provided with gradient through holes. The gradient through hole refers to the size of the cage sleeve gradually changes in the thickness direction. The bottom of the valve stem is inserted into the three-stage cage sleeve and can slide up and down relative to the three-stage cage sleeve to realize the opening degree adjustment of the cage sleeve.

[0006] Preferably, the gradient through hole on the side wall of the one-stage cage sleeve is a gradually changing round hole, the gradient through hole of the two-stage cage sleeve is a gradually changing rectangular hole, and the gradient through hole of the three-stage cage sleeve is a gradually changing trapezoidal hole.

[0007] Preferably, the aperture of the gradually changing circular hole gradually decreases from outside to inside, the aspect ratio of the gradually changing rectangular hole gradually increases from outside to inside, and the gradually changing angle of the gradually changing trapezoidal hole gradually increases from outside to inside.

[0008] Preferably, the gradually changing rectangular holes on the secondary cage are staggered, and the gradually changing trapezoidal holes and the gradually changing through holes are arranged in multiple columns and multiple rows.

[0009] Preferably, the primary cage, the secondary cage and the tertiary cage are in a cylindrical structure, the primary cage and the secondary cage are connected by a first trapezoidal connecting rod, the larger area end of the first trapezoidal connecting rod is arranged towards the side of the secondary cage, the secondary cage and the tertiary cage are connected by a first trapezoidal connecting rod, and the larger area end of the second trapezoidal connecting rod is arranged towards the side of the secondary cage.

[0010] Preferably, the valve seat comprises a first throttle seat, a second throttle seat and a third throttle seat fixedly connected in sequence from top to bottom, the first throttle seat is sealingly connected with the bottom end of the inner side wall of the tertiary cage, and the first throttle seat, the second throttle seat and the third throttle seat are all provided with throttle holes in communication with the fluid outlet holes on the valve body.

[0011] Preferably, the diameters of the throttle holes on the first throttle seat, the second throttle seat and the third throttle seat gradually increase, and the throttle holes on the first throttle seat, the second throttle seat and the third throttle seat are staggered in the height direction.

[0012] Preferably, the bottom end face of the valve seat is threadedly connected with a snap ring, and the snap ring is fixed in the interior of the valve body.

[0013] Preferably, the mounting port between the valve cover and the valve stem is provided with a primary gland, a primary sealing packing, a secondary gland, a secondary sealing packing, a tertiary gland and a tertiary sealing packing in sequence from top to bottom.

[0014] Preferably, the inner side wall of the outer cage is provided with multiple flow guide grooves arranged uniformly.

[0015] The cage type pressure reducing throttle valve has the following beneficial effects: 1. The cage type pressure reducing throttle valve uses a valve core with a tertiary cage and an outer cage, and compared with a traditional single-stage, double-stage and three-stage throttle valve, the pressure drop range is improved due to the arrangement of the gradually changing through holes, the number of throttle valves during operation can be effectively reduced, and the operation time and cost are reduced. 2. The cage type pressure reducing throttle valve uses gradually changing circular holes, gradually changing rectangular holes arranged staggered, and gradually changing trapezoidal holes, which can effectively reduce the erosion and damage of the valve core caused by fluid power, and can make the fluid flow stably in the flow passage, greatly increasing the service life of the throttle valve. 3. The cage sleeve type pressure reducing throttle valve, the throttle valve seat is composed of three layers of throttle valve seat, a plurality of gradually changing round holes are arranged on each layer, so that the stress concentration position of throttling operation is changed to the throttle valve seat, the throttle valve seat is designed in this way to grade dissipate energy, prolong the service life of the throttle valve, and realize high-efficiency throttling and equipment protection at the same time; 4. The cage sleeve type pressure reducing throttle valve, multi-stage packing seal is used between the valve cover and the valve body, which greatly improves the sealing performance of the throttle valve under high pressure conditions; 5. The cage sleeve type pressure reducing throttle valve, the throttle valve seat is provided with a snap ring which is threadedly connected with the valve core, so that the throttle valve seat can be replaced conveniently, and the maintenance cost is greatly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a sectional view of the cage sleeve type pressure reducing throttle valve of the present application; Figure 2 It is a structural schematic view of the valve core in the cage sleeve type pressure reducing throttle valve of the present application; Figure 3 It is a partial sectional view of the valve core in the cage sleeve type pressure reducing throttle valve of the present application; Figure 4 It is a structural schematic view of the outer cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 5 It is a three-dimensional structural schematic view of the cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 6 It is a longitudinal sectional structural schematic view of the cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 7 It is a three-dimensional structural schematic view of the first cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 8 It is a three-dimensional structural schematic view of the second cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 9 It is a three-dimensional structural schematic view of the third cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 10 It is a partial structural schematic view of the cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 11 It is a distribution diagram of the throttle holes of each stage of cage sleeve in the cage sleeve type pressure reducing throttle valve of the present application; Figure 12 It is a three-dimensional structural schematic view of the valve seat in the cage sleeve type pressure reducing throttle valve of the present application; Figure 13 It is a transverse sectional view of the valve seat in the cage sleeve type pressure reducing throttle valve of the present application; Figure 14 It is a distribution diagram of the throttle holes of each layer of the valve seat in the cage sleeve type pressure reducing throttle valve of the present application.

[0017] In the diagram, 1-fluid inlet, 2-safety relief valve, 3-valve body, 4-valve cover, 5-third-stage gland, 6-valve stem, 7-third-stage sealing packing, 8-second-stage gland, 9-second-stage sealing packing, 10-first-stage gland, 11-first-stage sealing packing, 12-O-ring seal, 13-outer cage, 1301-outer cage clearance, 14-guide groove, 15-first-stage cage, 16-gradient circular hole, 17-second-stage cage. 18-Gradual rectangular hole, 19-Three-stage cage sleeve, 20-Gradual trapezoidal hole, 21-First-layer throttling valve seat, 2101-First connecting disc, 22-First-layer valve seat gradual circular hole, 23-Second-layer throttling valve seat, 2301-Second connecting disc, 24-Second-layer valve seat gradual circular hole, 25-Third-layer throttling valve seat, 2501-Third connecting disc, 26-Third-layer valve seat gradual circular hole, 27-Snap ring, 28-Fluid outlet.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0020] It should be noted that in the description of this invention, the terms "lateral," "longitudinal," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] Reference Figures 1 to 6 In this preferred embodiment, a cage-type pressure reducing throttle valve includes a valve body 3, a valve cover 4, a valve seat, and a valve stem 6. The valve body 3 has a fluid inlet 1 and a fluid outlet 28. A valve core is provided between the fluid inlet 1 and the fluid outlet 28. The valve core includes a three-stage cage 19, a two-stage cage 17, a one-stage cage 15, and an outer cage 13, which are fixedly connected from the inside to the outside. The valve seat is sealed to the bottom of the inner side wall of the three-stage cage 19. The side walls of the three-stage cage 19, the two-stage cage 17, and the one-stage cage 15 are all provided with a gradual through hole. The gradual through hole refers to the gradual change in size (including both gradual increase and gradual decrease) in the thickness direction of the cage. The bottom of the valve stem 6 is inserted into the interior of the three-stage cage 19 and can slide up and down relative to it to adjust the opening degree of the cage.

[0022] The three-stage cage sleeve 19, the second-stage cage sleeve 17, the first-stage cage sleeve 15, and the outer cage sleeve 13 are coaxially arranged. The outer cage sleeve 13 and the first-stage cage sleeve 15 are fixed by an interference fit, and the valve core is positioned by the internal structure of the valve body 3.

[0023] Specifically, in this embodiment, referring to Figures 5 to 11 The gradual through holes on the side wall of the first-stage cage sleeve 15 are gradual round holes 16, the gradual through holes on the second-stage cage sleeve 17 are gradual rectangular holes 18, and the gradual through holes on the third-stage cage sleeve 19 are gradual trapezoidal holes 20.

[0024] The diameter of the gradient circular holes 16 gradually decreases from the outside to the inside, the aspect ratio of the gradient rectangular holes 18 gradually increases from the outside to the inside, and the gradient angle of the gradient trapezoidal holes 20 gradually increases from the outside to the inside. The gradient rectangular holes 18 on the secondary cage sleeve 17 are staggered, and the gradient trapezoidal holes 20 and the gradient through holes are provided in multiple columns and rows.

[0025] In this embodiment, the gradient circular holes 16 are set to 20 columns with 12 holes per row, the gradient rectangular holes 18 are set to 20 columns and are staggered, and the gradient trapezoidal holes 20 are set to 20 columns with 6 holes per row.

[0026] In this embodiment, refer to Figure 5 The first-stage cage sleeve 15, the second-stage cage sleeve 17, and the third-stage cage sleeve 19 are cylindrical structures. The first-stage cage sleeve 15 and the second-stage cage sleeve 17 are connected by a first trapezoidal connecting rod. The larger end of the first trapezoidal connecting rod is set towards the second-stage cage sleeve 17. The second-stage cage sleeve 17 and the third-stage cage sleeve 19 are connected by a first trapezoidal connecting rod. The larger end of the second trapezoidal connecting rod is set towards the second-stage cage sleeve 17.

[0027] Specifically, refer to Figures 12 to 14 The valve seat comprises a first-layer throttling valve seat 21, a second-layer throttling valve seat 23, and a third-layer throttling valve seat 25, which are fixedly connected from top to bottom. The first-layer throttling valve seat 21 is sealed to the bottom of the inner wall of the third-stage cage 19. Each of the first-layer throttling valve seat 21, the second-layer throttling valve seat 23, and the third-layer throttling valve seat 25 is provided with a throttling orifice communicating with the fluid outlet 28 on the valve body 3. In order to change the stress concentration range, achieve efficient throttling, and reduce the erosion wear and erosion damage to the valve core, the valve seat adopts a three-layer structure.

[0028] Reference Figure 14The diameter of the throttling orifices on the first-layer throttling valve seat 21, the second-layer throttling valve seat 23, and the third-layer throttling valve seat 25 gradually increases, and the throttling orifices on the first-layer throttling valve seat 21, the second-layer throttling valve seat 23, and the third-layer throttling valve seat 25 are staggered in the height direction. The first-layer throttling valve seat 21, the second-layer throttling valve seat 23, and the third-layer throttling valve seat 25 are respectively provided with a first-layer valve seat gradual circular hole 22, a second-layer valve seat gradual circular hole 24, and a third-layer valve seat gradual circular hole 26. The distribution pattern of the first-layer valve seat gradual circular hole 22, the second-layer valve seat gradual circular hole 24, and the third-layer valve seat gradual circular hole 26 is the same, only the size is different. Specifically, the gradual circular holes 16 on each layer of throttling valve seat are staggered by 15° in each layer. The bottom face of the valve seat is threaded to the retaining ring 27, which is fixed inside the valve body 3. The retaining ring 27 is screwed onto the bottom of the throttle valve seat, which facilitates the disassembly and maintenance of the valve seat.

[0029] The mounting port between the valve cover 4 and the valve stem 6 is provided with, from top to bottom, a primary gland 10, a primary sealing packing 11, a secondary gland 8, a secondary sealing packing 9, a tertiary gland 5, and a tertiary sealing packing 7. Several O-rings 12 are also provided between the inner wall of the mounting port and the primary sealing packing 11 to improve sealing performance.

[0030] The inner wall of the outer cage 13 is provided with multiple evenly arranged guide grooves 14. The flow of fluid is guided by the guide grooves 14.

[0031] The working process of this cage-type pressure reducing throttle valve is as follows: First, the fluid enters the flow channel of the valve body 3 through the fluid inlet 1. The fluid enters the outer cage 13 through the inlet of the outer cage 13. Within the outer cage gap 1301, the fluid's own collision reduces its own power, thus weakening the fluid's energy before it enters the first-stage cage 15. The fluid passes through the gradually changing circular hole 16 between the outer cage gap 1301 and the first-stage cage 15, and enters the gap between the first-stage cage 15 and the second-stage cage 17. The fluid energy is further dissipated through the gradually changing circular hole 16. Furthermore, the fluid passes through the gradually changing rectangular hole 18 on the inner wall of the second-stage cage 17, and enters the gap between the second-stage cage 17 and the third-stage cage 19. The fluid turbulence is reduced and the fluid energy is further reduced through the gradually changing rectangular hole 18. Finally, the fluid passes through the gradually changing trapezoidal hole 20 on the inner wall of the third-stage cage 19, and enters the gap between the third-stage cage 19 and the valve stem 6. The fluid energy is further reduced through the gradually changing trapezoidal hole 20, thus stabilizing the fluid flow. By sliding the valve stem 6 up and down, the number of throttling holes on the valve core can be controlled, thereby controlling the flow rate and pressure. When the fluid flows from the gap between the three-stage cage sleeve 19 and the valve stem 6 to the fluid outlet 28, the fluid will pass through the throttling device composed of three-layer throttling valve seats 25, thereby further controlling the fluid dynamics to maintain the stability of the fluid flow, thereby achieving control of the fluid flow rate and pressure.

[0032] The cage-type pressure-reducing throttle valve proposed in this embodiment has the following beneficial effects: 1. Cage-type pressure reducing throttle valve, which uses a valve core with a three-stage cage sleeve 19 and an outer cage sleeve 13, compared with traditional single-stage, double-stage and three-stage throttle valves, improves the pressure drop range by setting a gradual through hole, which can effectively reduce the number of throttle valves during operation, reduce operation time and operation cost. 2. This cage-type pressure reducing throttle valve utilizes gradually changing round holes 16, gradually changing rectangular holes 18 arranged in an alternating pattern, and gradually changing trapezoidal holes 20. This effectively reduces hydrodynamic forces, lowers the erosion and wear on the valve core, and enables the fluid to flow stably in the flow channel, greatly increasing the lifespan of the throttle valve. 3. Cage-type pressure reducing throttle valve, the throttle valve seat is composed of three layers of throttle valve seat 25, each layer is provided with several gradually changing circular holes 16, so that the stress concentration position of throttle operation is changed to the throttle valve seat. This design of the throttle valve seat can dissipate energy in stages, extend the service life of the throttle valve, and achieve efficient throttle and equipment protection at the same time. 4. This cage-type pressure reducing throttle valve uses multi-stage packing seal between the valve cover 4 and the valve body 3, which greatly improves the sealing performance of the throttle valve under high pressure conditions. 5. Cage-type pressure reducing throttle valve: The throttle valve seat is equipped with a retaining ring 27, which is threadedly connected to the valve core, making it easy to replace and greatly reducing maintenance costs.

[0033] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A cage-type pressure-reducing throttle valve, comprising a valve body, a valve cover, a valve seat, and a valve stem, wherein the valve body has a fluid inlet and a fluid outlet, and a valve core is disposed between the fluid inlet and the fluid outlet, characterized in that, The valve core includes a three-stage cage sleeve, a two-stage cage sleeve, a one-stage cage sleeve, and an outer cage sleeve that are fixedly connected from the inside to the outside. The valve seat is sealed to the bottom of the inner side wall of the three-stage cage sleeve. The side walls of the three-stage cage sleeve, the two-stage cage sleeve, and the one-stage cage sleeve are all provided with a gradual through hole. The gradual through hole refers to the gradual change in size in the thickness direction of the cage sleeve. The bottom of the valve stem is inserted into the interior of the three-stage cage sleeve and can slide up and down relative to it to adjust the opening degree of the cage sleeve.

2. The cage-type pressure-reducing throttle valve as described in claim 1, characterized in that, The gradual through holes on the side wall of the first-level cage are gradual circular holes, the gradual through holes on the second-level cage are gradual rectangular holes, and the gradual through holes on the third-level cage are gradual trapezoidal holes.

3. The cage-type pressure-reducing throttle valve as described in claim 2, characterized in that, The diameter of the gradient circular hole gradually decreases from the outside to the inside, the aspect ratio of the gradient rectangular hole gradually increases from the outside to the inside, and the gradient angle of the gradient trapezoidal hole gradually increases from the outside to the inside.

4. The cage-type pressure-reducing throttle valve as described in claim 2, characterized in that, The gradient rectangular holes on the secondary cage are arranged in an alternating pattern, and the gradient trapezoidal holes and gradient through holes are arranged in multiple columns and rows.

5. The cage-type pressure-reducing throttle valve as described in claim 1, characterized in that, The first-level cage sleeve, the second-level cage sleeve, and the third-level cage sleeve are cylindrical structures. The first-level cage sleeve and the second-level cage sleeve are connected by a first trapezoidal connecting rod, with the larger end of the first trapezoidal connecting rod facing the second-level cage sleeve. The second-level cage sleeve and the third-level cage sleeve are connected by a first trapezoidal connecting rod, with the larger end of the second trapezoidal connecting rod facing the second-level cage sleeve.

6. The cage-type pressure-reducing throttle valve as described in claim 1, characterized in that, The valve seat includes a first-layer throttling valve seat, a second-layer throttling valve seat, and a third-layer throttling valve seat that are fixedly connected from top to bottom. The first-layer throttling valve seat is sealed to the bottom of the inner wall of the third-stage cage. The first-layer throttling valve seat, the second-layer throttling valve seat, and the third-layer throttling valve seat are all provided with throttling holes that communicate with the fluid outlet holes on the valve body.

7. The cage-type pressure-reducing throttle valve as described in claim 6, characterized in that, The diameter of the throttling orifice on the first-layer, second-layer, and third-layer throttling valve seats gradually increases, and the throttling orifices on the first-layer, second-layer, and third-layer throttling valve seats are staggered in the height direction.

8. The cage-type pressure-reducing throttle valve as described in claim 1, characterized in that, The bottom end face of the valve seat is threadedly connected to the retaining ring, which is fixed inside the valve body.

9. The cage-type pressure-reducing throttle valve as described in claim 1, characterized in that, The mounting port between the valve cover and the valve stem is provided with a first-stage gland, a first-stage sealing packing, a second-stage gland, a second-stage sealing packing, a third-stage gland, and a third-stage sealing packing in sequence from top to bottom.

10. The cage-type pressure-reducing throttle valve as described in any one of claims 1 to 9, characterized in that, The inner wall of the outer cage is provided with multiple evenly arranged guide grooves.

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