Three-way flush shut-off valve of ammonia carbon analyzer

Abstract

This utility model discloses a three-way flushing shut-off valve for an ammonia-carbon analyzer, comprising a valve body, a main valve core, and a three-way flow channel disposed within the valve body, each communicating with a medium inlet flow channel and two medium outlet flow channels respectively. A main valve seat is provided on the flow channel communicating with the medium inlet flow channel. The lower valve head of the main valve core is located in the main valve seat, and its upper end passes through the upper valve cover and connects to the main actuator. Secondary valve assemblies for connecting to manual control mechanisms are provided on the flow channels communicating with the two medium outlet flow channels respectively. The medium inlet flow channel is mounted on the lower valve body, and a guide hole communicating with the medium inlet flow channel is opened at the top of the lower valve body. A hollow guide post with a flow channel hole is provided at the lower end of the valve head of the main valve core, slidingly engaging with the guide hole. The lower valve body and the upper valve cover are detachably connected to the valve body via bolts and nuts. This utility model features a simple structure, easy disassembly, easy maintenance, good sealing effect, smooth valve operation, and long-term safe online operation.

Description

Technical Field

[0001] This utility model relates to a valve structure, specifically a three-way flushing shut-off valve for an ammonia carbon analyzer. Background Technology

[0002] The ammonia-carbon analyzer is primarily used to monitor the molar ratio of NH3 to CO2 in the urea synthesis reaction, ensuring reaction efficiency and preventing equipment corrosion. In the urea plant, the three-way flushing shut-off valve of the ammonia-carbon analyzer is a key component ensuring process safety and analytical accuracy. The function of the three-way shut-off valve is as follows:

[0003] 1) Switching the flow path: Switch the sample flow, bypass or calibration medium when the analyzer is sampling, calibrating or maintaining.

[0004] 2) Safety shut-off: When an abnormality is detected (such as proportional imbalance or excessive pressure), the connection between the analyzer and the process pipeline is quickly shut off to prevent leakage of corrosive media.

[0005] In ammonia and carbon analyzers, the three-way flushing shut-off valve plays a crucial role. The three-way flushing shut-off valve mechanism is relatively complex, requiring multiple interconnected channels (one media inlet channel and two media outlets), necessitating the welding and assembly of multiple channels. Currently, domestic ammonia and carbon analyzer equipment relies heavily on imports, resulting in high prices. During operation, it is prone to problems such as external leakage, internal leakage (due to deformation of the valve body sealing surface after extensive welding, affecting valve sealing), jamming, valve malfunction due to crystallization, and damage to the sealing surface. Furthermore, the welded valve body to the pipeline results in an irregularly shaped valve body, hindering simple maintenance and repair, and making repair impossible. Summary of the Invention

[0006] The purpose of this utility model is to solve the above-mentioned technical problems and provide a three-way flushing shut-off valve for an ammonia carbon analyzer that is simple in structure, easy to disassemble, easy to maintain, has good sealing effect, smooth valve operation, and can operate safely online for a long period of time.

[0007] The technical solution includes a valve body, a main valve core, and a three-way flow channel disposed within the valve body, each communicating with a medium inlet flow channel and two medium outlet flow channels respectively. A main valve seat is provided on the flow channel communicating with the medium inlet flow channel of the three-way flow channel. The lower valve head of the main valve core is located in the main valve seat, and its upper end passes through the upper valve cover and connects to the main actuator. Secondary valve assemblies for connecting to manual control mechanisms are provided on the flow channels communicating with the two medium outlet flow channels of the three-way flow channel respectively. The medium inlet flow channel is mounted on the lower valve body, and a guide hole communicating with the medium inlet flow channel is opened at the top of the lower valve body. A hollow guide post with a flow channel hole is provided at the lower end of the valve head of the main valve core, which slides in cooperation with the guide hole. The guide post has a flow channel hole. The lower valve body and the upper valve cover are detachably connected to the valve body by bolts and nuts.

[0008] A main sealing packing assembly is installed between the upper valve cover and the main valve core. The main sealing packing assembly consists of, from bottom to top, a first guide sleeve, a lower packing pad, a lower packing, a third guide sleeve, an upper packing, a packing gland, and a packing pressure plate. The first guide sleeve contains a second guide sleeve, and the packing gland contains a fourth guide sleeve. The packing pressure plate is detachably connected to the upper valve cover by bolts and nuts to compress the upper and lower packing.

[0009] The secondary valve assembly includes a secondary valve seat located on the flow channel that connects the three-way flow channel and the medium outlet flow channel. The front end of the secondary valve core is located in the secondary valve seat, and the rear end passes through the valve body and the outer bracket and is connected to the manual control mechanism.

[0010] A secondary sealing packing assembly is provided between the secondary valve core and the valve body. The secondary sealing packing assembly includes a packing box and a secondary packing pad, secondary packing, secondary packing gland and secondary packing pressure plate installed from front to back in the packing box. The secondary packing pressure plate is detachably connected to the outer bracket in front by bolts and nuts for pressing the secondary packing.

[0011] The front end of the secondary valve seat has a front sealing surface that mates with the front end of the valve head of the secondary valve core, and the front end of the stuffing box has a rear sealing surface that mates with the rear end of the valve head of the secondary valve core.

[0012] Two media outlet channels are installed in two branch outlet pipe fittings, which are detachably connected to the valve body via bolts and nuts.

[0013] The valve body is provided with a steam flow channel, and the branch outlet pipe fitting is also provided with a steam flow channel. The steam flow channel on one side of the branch outlet pipe fitting is connected to one end of the steam flow channel on the valve body via a steam pipe, and the other end of the steam flow channel on the valve body is connected to the steam flow channel on the other side of the branch outlet pipe fitting via another steam pipe.

[0014] The two ends of the steam pipe are connected to the diversion outlet pipe fitting and the valve body respectively via loose threaded connections.

[0015] Beneficial effects:

[0016] A guide hole communicating with the medium inlet channel is opened at the top of the lower valve body. A hollow guide post is provided at the lower end of the valve head of the main valve core, which slides in cooperation with the guide hole. When the valve is opened or closed, the guide post can slide in the guide hole to guide the movement of the valve head, improve the stability of the valve core, and reduce the occurrence of jamming problems. The bottom of the guide post is a hollow guide post at the lower end of the valve head, with a flow channel hole. The medium can flow from the medium inlet channel, the guide hole, and the guide post into the main valve seat on the three-way flow channel through the flow channel hole. When the valve is closed, the main valve core will be subjected to the counter thrust (upward) from the high-pressure working medium below and the output force (upward) of the main actuator above. The forces in both directions act on the valve head of the main valve core at the same time, so that the sealing surface of the valve head and the sealing surface of the valve seat correspond to and fit tightly, greatly improving the sealing effect.

[0017] The upper valve cover, the lower valve body with a medium inlet flow channel, and the diversion outlet pipe with a medium outlet flow channel are all detachably connected to the main valve body. This ensures a sealing effect and facilitates maintenance, repair, and replacement of parts in case of crystallization or leakage, thus preventing the entire equipment from being scrapped.

[0018] Different packing assemblies are used to effectively seal the main valve core and secondary valve core, further improving guiding and sealing performance, enabling the three-way flushing shut-off valve to operate stably for a long time in corrosive media environments. Furthermore, in the secondary valve assembly, the front end of the secondary valve seat has a front sealing surface that mates with the front end of the valve head of the secondary valve core, and the front end of the packing box has a rear sealing surface that mates with the rear end of the valve head of the secondary valve core. By setting the front and rear sealing surfaces, the valve head of the secondary valve core can seal the media outlet flow channel in the fully closed state and seal the gap between the packing and the valve core in the fully open state, effectively protecting the packing and further improving sealing performance.

[0019] Steam channels are provided in both the valve body and the branch outlet pipe fittings, and the entire equipment is insulated to prevent jamming and crystallization. At the same time, the two ends of the steam pipe are detachably connected to the branch outlet pipe fittings and the valve body, respectively, which is easy to inspect and maintain.

[0020] This utility model has a simple structure, all parts are detachable, meet the needs of rapid maintenance, is easy to maintain, has a good sealing effect, smooth valve operation, and can operate safely online for a long period of time. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of this utility model.

[0022] Figure 2 for Figure 1 A cross-sectional view of MM.

[0023] Figure 3 This is a partial state diagram when the secondary valve core is closed.

[0024] Figure 4 Diagram showing the main valve core's open state.

[0025] Figure 5 Diagram showing the main valve core in closed state.

[0026] Among them, 1-medium inlet flow channel, 2-first medium outlet flow channel, 3-second medium outlet flow channel, 4-valve body, 5-three-way flow channel, 6-main valve seat, 7-main valve core, 7.1-valve head, 7.2-guide post, 7.3-flow channel hole, 8-upper valve cover, 9-main actuator, 10-manual control mechanism, 11-secondary valve assembly, 12-lower valve body, 12.1-guide hole, 13-bolt, 14-nut, 15-main sealing packing assembly, 15.1-first guide sleeve, 15.2-lower packing pad, 15.3-lower packing, 15.4-third guide sleeve, 15.5-upper... 15.6-Packing gland, 15.7-Packing plate, 15.8-Second guide sleeve, 15.9-Fourth guide sleeve, 16-Secondary valve seat, 16.1-Front sealing surface, 16.2-Rear sealing surface, 17-Secondary valve core, 17.1-Valve head, 18-Outer support, 19-Secondary sealing packing assembly, 19.1-Packing box, 19.2-Secondary packing underfill, 19.3-Secondary packing, 19.4-Secondary packing gland, 19.5-Secondary packing plate, 20-First branch outlet fitting, 21-Secondary branch outlet fitting, 22-Steam flow channel, 23-Steam connection, 24-Gasket. Detailed Implementation

[0027] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the invention.

[0028] See Figures 1-2The valve body 4 has a three-way flow channel 5 that communicates with one medium inlet flow channel 1 and two medium outlet flow channels (first medium outlet flow channel 2 and second medium outlet flow channel 3). A main valve seat 6 is provided on the flow channel 5 that communicates with the medium inlet flow channel 1. The valve head 7.1 at the lower end of the main valve core 7 is located in the main valve seat 6, and its upper end passes through the upper valve cover 8 and connects to the main actuator 9. Secondary valve assemblies 11 that connect to the manual control mechanism 10 are provided on the flow channels 5 that communicate with the first medium outlet flow channel 2 and the second medium outlet flow channel 3, respectively. The medium inlet flow channel 1 is installed on the lower valve body 12, and the top of the lower valve body 12 has an opening for communication with the medium inlet flow channel 1. The guide hole 12.1 is connected to the main valve core 7. The lower end of the valve head 7.1 is provided with a hollow guide post 7.2 corresponding to the guide hole 12.1. The guide post 7.2 can slide in the guide hole 12.1. The guide post 7.2 has a flow channel hole 7.3. The medium from the medium inlet flow channel 1 flows into the main valve seat 6 through the hollow guide post 7.2 and the flow channel hole 7.3. Preferably, the lower valve body 12 and the upper valve cover 8 are detachably connected to the valve body 4 by bolts 13 and tightened with nuts 14. As needed, gaskets 24 are used for sealing. With the above connection method, the lower valve body 12 and the upper valve cover 8 can be easily removed from the valve body 4 during maintenance.

[0029] A main sealing packing assembly 15 is installed between the upper valve cover 8 and the main valve core 7. The main sealing packing assembly 15, from bottom to top, consists of a first guide sleeve 15.1, a lower packing pad 15.2, a lower packing 15.3, a third guide sleeve 15.4, an upper packing 15.5, a packing gland 15.6, and a packing pressure plate 15.7. A second guide sleeve 15.8 is housed within the first guide sleeve 15.1, and a fourth guide sleeve 15.9 is housed within the packing gland 15.6. The packing pressure plate 15.7 is threadedly connected to the upper valve cover 8 by bolts 13 and tightened with nuts 14 to compress the upper packing 15.5 and the lower packing 15.3, facilitating quick disassembly and maintenance. The tight fit of the guide sleeves, packing, and pressure plate seals the gap between the main valve core 7 and the upper valve cover 8, preventing media leakage.

[0030] Taking the secondary valve assembly 11 installed on the flow channel connecting the three-way flow channel 5 and the first medium outlet flow channel 2 as an example, the secondary valve assembly 11 includes a secondary valve seat 16 located on the flow channel connecting the three-way flow channel 5 and the first medium outlet flow channel 2, the valve head 17.1 at the front end of the secondary valve core 17 is located in the secondary valve seat 16, and the rear end passes through the valve body 4 and the outer bracket 18 and is connected to the manual control mechanism 10.

[0031] A secondary sealing packing assembly 19 is provided between the secondary valve core 17 and the valve body 4. The secondary sealing packing assembly includes a packing box 19.1 and, installed from front to back within the packing box 19.1, a secondary packing pad 19.2, secondary packing 19.3, a secondary packing gland 19.4, and a secondary packing pressure plate 19.5. The secondary packing pressure plate is threadedly connected to the front outer bracket 18 by bolts 13 and tightened with nuts 14 to compress the secondary packing 19.3. The tight fit of the guide sleeve, packing, and pressure plate seals the gap between the main valve core 7 and the upper valve cover 8, preventing media leakage and facilitating quick disassembly and maintenance. Further details can be found in the following sections. Figure 3 The secondary valve seat 16 has a front sealing surface 16.1 that mates with the front end of the valve head 17.1 of the secondary valve core 17, and the stuffing box 19.1 has a rear sealing surface 16.2 that mates with the valve head 17.1 of the secondary valve core 17, to effectively protect the packing. The upper packing 15.5, lower packing 15.3, and secondary packing 19.3 are preferably made of polytetrafluoroethylene (PTFE), suitable for corrosive media environments, and have good sealing performance.

[0032] The first medium outlet channel 2 and the second medium outlet channel 3 are respectively installed in the first diversion outlet pipe fitting 20 and the first diversion outlet pipe fitting 21. The diversion outlet pipe fittings are arranged opposite each other on both sides of the valve body 4 and are threadedly connected to the valve body 4 by bolts 13 and tightened with nuts 14. The valve body 4 is provided with a steam channel 22, and the diversion outlet pipe fittings are also provided with a steam channel 22. The steam channel 22 on the first diversion outlet pipe fitting 2 is connected to one end of the steam channel 22 on the valve body 4 via a steam pipe 23. The other end of the steam channel 22 on the valve body 4 is connected to the steam channel 22 on the second diversion outlet pipe fitting 21 via another steam pipe 23, so as to achieve the insulation of the valve body 4 and the flow of the two outlet media by steam. Preferably, the two ends of the steam pipe 23 are respectively connected to the diversion outlet pipe fitting and the valve body 4 by a loose thread to meet the needs of quick disassembly and maintenance.

[0033] Working principle:

[0034] See Figure 4 When the main valve is open, the main actuator 9 drives the main valve core 7 to move downward against the pressure of the medium. The guide column 7.2 moves downward steadily under the guidance of the guide hole 12.1, opening the passage between the medium inlet flow channel 1 and the three-way flow channel 5. At the same time, the manual control mechanism 10 controls the secondary valve core 17 of the secondary valve assembly 11 to move backward (moving outward in the figure), opening the passage between the three-way flow channel 5 and the first medium outlet flow channel 2 and the second medium outlet flow channel 3. In the fully open state, the rear end of the valve head 17.1 of the secondary valve core 17 is sealed and fitted with the rear sealing surface 16.2 of the front end of the packing box 19.1, effectively protecting the packing.

[0035] The medium enters through the medium inlet channel 1 of the lower valve body 12, flows through the guide hole 12.1, guide post 7.2, and flow channel hole 7.3 into the main valve seat 6, and then enters the three-way flow channel 5 through the sealing gap between the valve head 7.1 of the main valve core 7 and the main valve seat 6. Finally, it flows out through the corresponding first medium outlet flow channel 2 and second medium outlet flow channel 3 of the two secondary valve seats 16. In addition, according to specific operating conditions, the manual control mechanisms 10 on both sides can control the opening degree of the corresponding secondary valve core 17, or realize the state of only one secondary valve assembly 11 being open and the other secondary valve assembly 11 being closed.

[0036] See Figure 5 When the main valve is closed, the main actuator 9 drives the main valve core 7 to move upward under the pressure of the medium. The guide column 7.2 moves upward steadily under the guidance of the guide hole 12.1, so that the valve head of the main valve core 7 is tightly fitted with the sealing surface of the main valve seat 6, closing the passage between the medium inlet channel 1 and the three-way channel 5. At the same time, the manual control mechanism 10 controls the secondary valve core 17 of the secondary valve assembly 11 to move forward (moving towards the main valve core 7 in the figure), closing the passage between the three-way channel 5 and the first medium outlet channel 2 and the second medium outlet channel 3. In the closed state, the front end of the valve head 17.1 of the secondary valve core 17 is tightly fitted with the front sealing surface 16.1 of the front end of the secondary valve seat 16.

[0037] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of this inventive concept, various simple modifications can be made to the technical solution, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in this utility model and are all within the protection scope of this invention.

Claims

1. A three-way flushing shut-off valve for an ammonia carbon analyzer, comprising a valve body, a main valve core, and a three-way flow channel disposed within the valve body, each communicating with a medium inlet flow channel and two medium outlet flow channels respectively. A main valve seat is disposed on the flow channel communicating with the medium inlet flow channel. The lower valve head of the main valve core is located in the main valve seat, and its upper end passes through an upper valve cover and is connected to a main actuator. The valve is characterized in that... Each of the three-way flow channels, which are connected to the two medium outlet flow channels respectively, is equipped with a secondary valve assembly for connecting a manual control mechanism; the medium inlet flow channel is installed on the lower valve body, and the top of the lower valve body has a guide hole that communicates with the medium inlet flow channel; the lower end of the valve head of the main valve core is provided with a hollow guide post that slides with the guide hole, and the guide post has a flow channel hole; the lower valve body and the upper valve cover are both detachably connected to the valve body by bolts and nuts.

2. The three-way flushing shut-off valve of the ammonia carbon analyzer as described in claim 1, characterized in that, A main sealing packing assembly is installed between the upper valve cover and the main valve core. The main sealing packing assembly consists of, from bottom to top, a first guide sleeve, a lower packing pad, a lower packing, a third guide sleeve, an upper packing, a packing gland, and a packing pressure plate. The first guide sleeve contains a second guide sleeve, and the packing gland contains a fourth guide sleeve. The packing pressure plate is detachably connected to the upper valve cover by bolts and nuts to compress the upper and lower packing.

3. The three-way flushing shut-off valve of the ammonia carbon analyzer as described in claim 1, characterized in that, The secondary valve assembly includes a secondary valve seat located on the flow channel that connects the three-way flow channel and the medium outlet flow channel. The front end of the secondary valve core is located in the secondary valve seat, and the rear end passes through the valve body and the outer bracket and is connected to the manual control mechanism.

4. The three-way flushing shut-off valve of the ammonia carbon analyzer as described in claim 3, characterized in that, A secondary sealing packing assembly is provided between the secondary valve core and the valve body. The secondary sealing packing assembly includes a packing box and a secondary packing pad, secondary packing, secondary packing gland and secondary packing pressure plate installed from front to back in the packing box. The secondary packing pressure plate is detachably connected to the outer bracket in front by bolts and nuts for pressing the secondary packing.

5. The three-way flushing shut-off valve of the ammonia carbon analyzer as described in claim 4, characterized in that, The front end of the secondary valve seat has a front sealing surface that mates with the front end of the valve head of the secondary valve core, and the front end of the stuffing box has a rear sealing surface that mates with the rear end of the valve head of the secondary valve core.

6. The three-way flushing shut-off valve of the ammonia carbon analyzer as described in any one of claims 1-5, characterized in that, Two media outlet channels are installed in two branch outlet pipe fittings, which are detachably connected to the valve body via bolts and nuts.

7. The three-way flushing shut-off valve of the ammonia carbon analyzer as described in claim 6, characterized in that, The valve body is provided with a steam flow channel, and the branch outlet pipe fitting is also provided with a steam flow channel. The steam flow channel on one side of the branch outlet pipe fitting is connected to one end of the steam flow channel on the valve body via a steam pipe, and the other end of the steam flow channel on the valve body is connected to the steam flow channel on the other side of the branch outlet pipe fitting via another steam pipe.

8. The three-way flushing shut-off valve of the ammonia carbon analyzer as described in claim 7, characterized in that, The two ends of the steam pipe are connected to the diversion outlet pipe fitting and the valve body respectively via loose threaded connections.

Images