Material angle valve capable of clearing blockage on line

Abstract

The invention belongs to the technical field of polyester chemical production, and particularly relates to a material angle valve capable of online unblocking, which comprises a diaphragm, a valve rod, a valve head, a valve seat, a displacement monitoring alarm device, a gas inlet pipeline, a gas exhaust pipeline and a gas source quick connector, the valve rod comprises a spring a, a piston, a stuffing box, an outer shaft sleeve and an inner shaft; the piston, the stuffing box, the outer shaft sleeve and the inner shaft jointly define a sealing cavity, and the sealing cavity, the air inlet pipeline and the exhaust pipeline are communicated with an air source quick connector at the same time. The displacement monitoring and alarming device is used for giving an alarm when the displacement monitoring and alarming device moves upwards in the inner shaft till the gap between the valve head and the valve seat is 6-8 cm. According to the material angle valve capable of achieving on-line blockage clearing, the gap between the valve head and the valve seat can be enlarged through on-line operation, so that the angle valve has the on-line blockage clearing capacity, the problem that a reaction kettle is forced to stop for overhauling due to material breakage is effectively solved, and then the working efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of polyester chemical production, and in particular relates to a material angle valve capable of clearing blockage online. Background Art

[0002] Polyester (PET), also known as polyester or polyester resin, is currently mainly produced by the reaction of terephthalic acid and ethylene glycol. In polyester chemical enterprises, terephthalic acid and ethylene glycol are mixed in a certain proportion, and an esterification reaction is carried out in an esterification kettle to form an ester (PET monomer). The ester is transported into the prepolymerization kettle through a material pump, and a preliminary polymerization reaction is carried out under vacuum, catalyst, and high temperature conditions to generate a prepolymer with a low degree of polymerization (12-20) and a low viscosity (0.26dl / g). Under the action of the height difference and vacuum difference between the prepolymerization kettle and the final polymerization kettle, the material enters the final polymerization kettle, and the final polymerization reaction is completed under high vacuum, stirring, film drawing and high temperature conditions to form a PET high molecular polymer, which is then extruded and pressurized by a melt discharge pump (gear pump) and filtered by a melt filter for pelletizing and spinning.

[0003] In the polycondensation stage, the power is generated by the position difference between the outlet of the prepolymerization kettle and the inlet of the final polymerization kettle and the pressure difference between the prepolymerization kettle and the final polymerization kettle to transport the materials. Figure 2 In the actual polyester production process, the stability of material flow is very important, which is the key factor in determining product quality. Therefore, in order to control the material flow with high precision and high sensitivity, the material angle valve flux gap is usually designed to be relatively small (the gap between the valve head and the valve seat in the fully open state is only 0.8-1cm).

[0004] In the polyester reaction process, it is basically carried out under high temperature conditions. In the long-term continuous production process, carbonized materials may form on the wall of the prepolymer (especially cationic) prepolymer reactor. Under the continuous flushing of the material, some of these carbonized materials will peel off. As the material is brought into the material angle valve between the prepolymer reactor and the final polymerization reactor, these carbonized materials that are larger than the flux gap of the angle valve will be stuck in front of the valve and gradually accumulate. Due to the relatively large hardness of these carbides, the carbonized materials cannot be squeezed and crushed through by relying solely on the potential difference and pressure difference under a vacuum state, resulting in problems such as poor material passing through the material angle valve and unstable material passing, affecting production stability and PET quality. In severe cases, the material angle valve may be completely blocked due to the bridging effect, and the material cannot pass through, resulting in a material cutoff in the final polymerization reactor, forcing the production unit to be shut down for maintenance.

[0005] From the above, it can be seen that the existing material angle valve is designed entirely based on an ideal production state, without considering the formation of infusible substances such as coke or foreign matter. In the actual continuous production process, the operation cycle of the device is long, and carbides are easily formed on the wall of the gas phase space of the reactor. These carbides gather in front of the valve to form large particles of carbides after the materials enter the angle valve, until the passage is completely blocked, normal materials cannot pass, and the device is forced to stop processing, resulting in large losses. At present, there is no timely and effective treatment method, which has brought great economic losses to many companies in the industry.

[0006] Therefore, it is necessary to improve the structure of the existing material angle valve in order to solve the above problems. Summary of the invention

[0007] The purpose of the present invention is to solve the problems existing in the above-mentioned prior art and to provide a material angle valve which can clear blockage online.

[0008] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0009] A material angle valve capable of clearing blockage online comprises a diaphragm, a valve stem, a valve head and a valve seat, wherein the diaphragm is fixed on the upper part of the valve stem, and further comprises a displacement monitoring alarm device, an air inlet pipeline, an exhaust pipeline and an air source quick connector;

[0010] The valve stem includes a spring a, a piston, a stuffing box, an outer sleeve, and an inner shaft; the spring a, the outer sleeve, and the inner shaft are all arranged vertically;

[0011] The spring a, the piston, the stuffing box and the valve head are arranged at intervals from top to bottom. The spring a and the piston are both located inside the outer sleeve. The upper end of the spring a is fixedly connected to the outer sleeve, and the stuffing box is fixed to the lower end of the outer sleeve.

[0012] The upper end of the inner shaft passes through the stuffing box, the piston and the spring a in sequence, and the lower end of the inner shaft is fixedly connected to the valve head;

[0013] When spring a is in the natural state, the gap between the valve head and the valve seat is d1, and d1 is 0.8-1cm;

[0014] The piston, stuffing box, outer sleeve and inner shaft together form a sealed chamber. The sealed chamber, air inlet pipeline and exhaust pipeline are connected with the air source quick connector at the same time. An air inlet valve is arranged on the air inlet pipeline and an exhaust valve is arranged on the exhaust pipeline.

[0015] The displacement monitoring alarm device is used to alarm when the inner shaft moves upward to the clearance between the valve head and the valve seat is d2, and d2 is 6-8cm.

[0016] As the preferred technical solution:

[0017] As described above, a material angle valve that can be cleared online, the displacement monitoring alarm device includes a limiter and a warning light, the limiter is fixed on the outer wall of the outer shaft sleeve and is located on one side of the spring a, the installation height of the limiter is equal to the height of the upper end of the inner shaft when the inner shaft moves upward to the gap between the valve head and the valve seat is d2, the limiter is used to control the warning light to light up when the height of the upper end of the inner shaft is equal to the installation height of the limiter.

[0018] As described above, a material angle valve that can be cleared for blockage online also includes an operator, which is connected to the air inlet valve and the exhaust valve at the same time. The operator is used to control the closing of the air inlet valve when the prompt light is on.

[0019] As described above, a material angle valve capable of clearing blockage online, the air intake pipeline and the exhaust pipeline are connected to form a Y-shaped pipeline, the Y-shaped pipeline is composed of pipeline I, pipeline II and pipeline III, the air intake valve is installed on pipeline I, the exhaust valve is installed on pipeline II, and pipeline III is connected to the gas source quick connector.

[0020] As described above, a material angle valve capable of clearing blockages online also includes a bracket, a pressure reducing valve and a positioner. The pressure reducing valve is connected to the pipeline I and the positioner at the same time, and the positioner is connected to the bracket.

[0021] As described above, a material angle valve that can be cleared for blockage online also includes a positioning pin located in the bracket, and the positioning pin simultaneously passes through the outer sleeve and the inner shaft horizontally, and the inner shaft and the outer sleeve are fixed and split by the positioning pin.

[0022] As described above, a material angle valve that can be cleared for blockage online also includes a locking device, which includes a slot and a bolt. The slot is fixed on the outer wall of the outer sleeve, and the threaded section of the bolt penetrates into the bracket from the outside of the bracket, and the end is located in the slot.

[0023] As described above, the material angle valve capable of clearing blockages online also includes a valve housing and a bellows fixed in the valve housing, wherein the bellows is sleeved on the inner shaft and has a length of 17-20 cm.

[0024] As described above, the material angle valve capable of online clearing has a valve housing designed as a jacket structure and is equipped with a heat medium inlet and a heat medium outlet, both of which are connected to the interlayer inside the jacket, and the heat medium inlet is located below the heat medium outlet.

[0025] Beneficial Effects

[0026] The material angle valve capable of online clearing of blockages of the present invention can increase the gap between the valve head and the valve seat through online operation, so that the angle valve has the ability of online clearing of blockages, effectively avoiding the problem of forced shutdown and maintenance due to material shortage in the reactor, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a structural schematic diagram of a material angle valve capable of online clearing of blockage according to the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of a material angle valve in the prior art;

[0029] Among them, 1- diaphragm, 2- spring b, 3- indicator plate, 4- positioner, 5- pressure reducing valve, 6- spring a, 7- positioning pin, 8- piston, 9- stuffing box, 10- air source quick connector, 11- limiter, 12- outer sleeve, 13- inner shaft, 14- lip weld, 15- bellows, 16- material outlet, 17- material inlet, 18- valve head, 19- heat medium inlet, 20- heat medium outlet, 21- inlet valve, 22- exhaust valve, 23- fixing screw, 24- locking device, 25- limiter. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0031] A material angle valve that can be cleared online, such as Figure 1 As shown, it includes a diaphragm 1, a spring b2, a valve stem, a valve head 18, a valve seat, a displacement monitoring alarm device, an air intake pipeline, an exhaust pipeline, a gas source quick connector 10, a bracket, a pressure reducing valve 5, a positioner 4, a positioning pin 7, a locking device 24, an operator 25, an indicator 3, an upper flange, a lower flange, a lip weld 14, a fixing screw 23, a valve housing and a bellows 15;

[0032] The diaphragm 1 is fixed above the valve stem, and the spring b2 is used to provide a force for the recovery of the compressed diaphragm 1;

[0033] The valve stem includes a spring a 6, a piston 8, a stuffing box 9, an outer sleeve 12 and an inner shaft 13;

[0034] The spring a6, the outer sleeve 12, and the inner shaft 13 are all arranged vertically; the spring a6, the piston 8, the stuffing box 9, and the valve head 18 are arranged at intervals from top to bottom, the spring a6 and the piston 8 are both located inside the outer sleeve 12, the upper end of the spring a6 is fixedly connected to the outer sleeve 12, and the stuffing box 9 is fixed to the lower end of the outer sleeve 12;

[0035] The upper end of the inner shaft 13 passes through the stuffing box 9, the piston 8 and the lower end of the spring a 6 in sequence, and the lower end of the inner shaft 13 is fixedly connected to the valve head 18;

[0036] When the spring a6 is in the natural state, the gap between the valve head 18 and the valve seat is d1 (0.8-1cm);

[0037] The piston 8, the stuffing box 9, the outer sleeve 12 and the inner shaft 13 together form a sealed chamber;

[0038] The air intake pipeline and the exhaust pipeline are connected to form a Y-shaped pipeline, and the Y-shaped pipeline is composed of pipeline I, pipeline II and pipeline III. Pipeline I is used for air intake and is equipped with an air intake valve 21. Pipeline II is used for exhaust and is equipped with an exhaust valve 22. Pipeline III is connected to the air source quick connector 10, and the air source quick connector 10 is connected to the sealing chamber.

[0039] The pressure reducing valve 5 is connected to the pipeline I and the positioner 4 at the same time, and the positioner 4 is connected to the bracket;

[0040] The positioning pin 7 is located in the bracket and simultaneously passes through the outer sleeve 12 and the inner shaft 13 transversely;

[0041] The locking device 24 includes a slot and a bolt. The slot is fixed on the outer wall of the outer sleeve 12. After the threaded section of the bolt penetrates into the bracket from the outside of the bracket, the end of the bolt is located in the slot.

[0042] The indicator plate 3 is fixed on the upper right side of the bracket, and the scale on the indicator plate corresponding to the pointer is the valve opening;

[0043] The lip weld 14 is located between the upper flange and the lower flange to ensure the sealing of the angle valve under vacuum;

[0044] The fixing screws 23 are used to fix the upper flange and the lower flange together;

[0045] The valve housing is designed as a jacket structure and is equipped with a heat medium inlet 19 and a heat medium outlet 20, both of which are connected with the interlayer inside the jacket, and the heat medium inlet 19 is located below the heat medium outlet 20;

[0046] The bellows 15 is fixed in the valve housing, and the bellows 15 is sleeved on the inner shaft 13 and has a length of 17-20 cm;

[0047] The displacement monitoring alarm device includes a stopper 11 and a warning light. The stopper 11 is fixed on the outer wall of the outer sleeve 12 and is located on one side of the spring a6. The installation height of the stopper 11 is equal to the height of the upper end of the inner shaft 13 when the inner shaft 13 moves upward to the gap between the valve head 18 and the valve seat is d2 (6-8cm). The stopper 11 is used to control the warning light to light up when the height of the upper end of the inner shaft 13 is equal to the installation height of the stopper 11;

[0048] The operator 25 is connected to the intake valve 21 and the exhaust valve 22 at the same time. The operator 25 is used to control the intake valve 21 to close when the warning light is on.

[0049] like Figure 1 As shown, the material enters the angle valve from the material inlet 17. When the material angle valve is blocked, the material amount at the material outlet 16 decreases sharply, and the liquid level curve of the subsequent reactor shows a trend of gradual decline. First, the automatic valve is put into manual state, and the valve is positioned and locked at 100%. At this time, the bolt of the locking device 24 can be aligned with the slot inserted into the locking device 24 to lock the outer sleeve 12 to prevent the reaction force of the subsequent operation of the inner shaft 13 from causing the outer sleeve 12 to slide. Then the on-site operator pulls out the positioning pin 7 to allow the inner shaft 13 to slide in the outer sleeve 12. Then, the operator controls the air intake valve 21 to open through the operator 25 to inflate the sealed chamber surrounded by the piston 8, the stuffing box 9, the outer sleeve 12, and the inner shaft 13. During this process, the inner shaft 13 rises continuously and compresses the spring a. 6. When the inner shaft 13 moves upward to the gap between the valve head 18 and the valve seat is d2, and the height of the upper end of the inner shaft 13 is equal to the installation height of the limiter 11, the limiter 11 controls the prompt light to light up. When the prompt light is on, the operator 25 controls the air inlet valve 21 to close, and the inflation process stops. Finally, after the central control operator confirms that the material angle valve is unobstructed, the on-site personnel control the exhaust valve 22 to open through the operator 25, so that the gas in the sealed cavity surrounded by the piston 8, stuffing box 9, outer shaft sleeve 12, and inner shaft 13 is discharged. In this process, under the reaction of the spring a 6, the inner shaft 13 returns to the initial position, the on-site operator resets the positioning pin 7, pulls the bolt of the locking device 24 out of the slot of the locking device 24, and the angle valve returns to the original control mode. At this point, the operation of unblocking the material angle valve is completed.

[0050] If the operator 25 is not installed, the on-site operator needs to directly control the air inlet valve 21 to open when inflation is required, directly control the air inlet valve 21 to close when the prompt light is on, and directly control the exhaust valve 22 to open when exhaust is required. Relatively speaking, the material angle valve with the operator 25 is more intelligent.

Claims

1. A material angle valve capable of clearing blockage online, comprising a diaphragm (1), a valve stem, a valve head (18), and a valve seat, wherein the diaphragm (1) is fixed above the valve stem, and is characterized in that: It also includes a displacement monitoring alarm device, an air intake pipeline, an air exhaust pipeline and an air source quick connector (10); The valve stem comprises a spring a (6), a piston (8), a stuffing box (9), an outer shaft sleeve (12), and an inner shaft (13); the spring a (6), the outer shaft sleeve (12), and the inner shaft (13) are all arranged vertically; The spring a (6), the piston (8), the stuffing box (9) and the valve head (18) are arranged at intervals from top to bottom, the spring a (6) and the piston (8) are both located inside the outer shaft sleeve (12), the upper end of the spring a (6) is fixedly connected to the outer shaft sleeve (12), and the stuffing box (9) is fixed to the lower end of the outer shaft sleeve (12); The upper end of the inner shaft (13) passes through the stuffing box (9), the piston (8) and the spring a (6) in sequence, and the lower end of the inner shaft (13) is fixedly connected to the valve head (18); When the spring a (6) is in a natural state, the gap between the valve head (18) and the valve seat is d1, and d1 is 0.8-1 cm; The piston (8), the stuffing box (9), the outer sleeve (12) and the inner shaft (13) together form a sealed chamber, and the sealed chamber, the air intake pipeline and the air exhaust pipeline are simultaneously connected to the air source quick connector (10), the air intake pipeline is provided with an air intake valve (21), and the air exhaust pipeline is provided with an air exhaust valve (22); The displacement monitoring alarm device is used to give an alarm when the inner shaft (13) moves upwards to a clearance d2 between the valve head (18) and the valve seat, wherein d2 is 6-8 cm.

2. The material angle valve capable of online clearing of blockage according to claim 1 is characterized in that: The displacement monitoring alarm device comprises a limiter (11) and a warning light. The limiter (11) is fixed on the outer wall of the outer shaft sleeve (12) and is located on one side of the spring a (6). The installation height of the limiter (11) is equal to the height of the upper end of the inner shaft (13) when the inner shaft (13) moves upward to a clearance d2 between the valve head (18) and the valve seat. The limiter (11) is used to control the warning light to light up when the height of the upper end of the inner shaft (13) is equal to the installation height of the limiter (11).

3. The material angle valve capable of online clearing of blockage according to claim 2 is characterized in that: The material angle valve capable of clearing blockage online also comprises an operator (25), which is connected to the air inlet valve (21) and the air outlet valve (22) at the same time. The operator (25) is used to control the air inlet valve (21) to close when the prompt light is on.

4. The material angle valve capable of online clearing of blockage according to claim 2 is characterized in that: The air intake pipeline and the exhaust pipeline are connected to form a Y-shaped pipeline, the Y-shaped pipeline is composed of pipeline I, pipeline II and pipeline III, the air intake valve (21) is installed on pipeline I, the exhaust valve (22) is installed on pipeline II, and pipeline III is connected to the gas source quick connector (10).

5. The material angle valve capable of online clearing of blockage according to claim 4 is characterized in that: The material angle valve capable of clearing blockage online further comprises a bracket, a pressure reducing valve (5) and a positioner (4); the pressure reducing valve (5) is connected to the pipeline I and the positioner (4) at the same time; and the positioner (4) is connected to the bracket.

6. The material angle valve capable of online clearing of blockage according to claim 5 is characterized in that: The material angle valve capable of clearing blockage online further comprises a positioning pin (7) located in the bracket, wherein the positioning pin (7) simultaneously transversely penetrates the outer shaft sleeve (12) and the inner shaft (13).

7. The material angle valve capable of online clearing of blockage according to claim 5, characterized in that: The material angle valve capable of online clearing also includes a locking device (24), the locking device (24) including a slot and a bolt, the slot being fixed on the outer wall of the outer shaft sleeve (12), the threaded section of the bolt being inserted into the bracket from the outside of the bracket, and the end of the bolt being located in the slot.

8. The material angle valve capable of online clearing of blockage according to claim 1, characterized in that: The material angle valve capable of clearing blockage online also comprises a valve housing and a bellows (15) fixed in the valve housing. The bellows (15) is sleeved on the inner shaft (13) and has a length of 17-20 cm.

9. The material angle valve capable of online clearing of blockage according to claim 8, characterized in that: The valve housing is designed as a jacket structure and is equipped with a heat medium inlet (19) and a heat medium outlet (20), both of which are connected to the interlayer inside the jacket, and the heat medium inlet (19) is located below the heat medium outlet (20).

Images