Special anti-crystallization three-way ball valve for urea

Abstract

The utility model discloses an anti-crystallization three-way ball valve special for urea, relates to the technical field of design and manufacture of three-way reversing valves used in chemical production, and aims to provide the anti-crystallization three-way ball valve special for urea production, which can effectively solve the anti-crystallization effect of the valve on a urea medium production line. And long-period online safe operation is achieved. The three-way valve comprises a three-way flow channel, a valve rod mechanism, a valve body and an executing mechanism. The three-way flow channel comprises a hexagon nut, a bolt, a metal wound gasket, a valve seat, a valve body, a valve cover and a ball body, and the three-way flow channel comprises an inlet flow channel, a first outlet flow channel and a second outlet flow channel; three flow channels of a three-way flow channel formed by the inlet flow channel, the first outlet flow channel and the second outlet flow channel are equally divided by 360 degrees, and the included angle of each flow channel is a large obtuse angle of 120 degrees; and the spherical surface of the sphere is matched with the three runners and is set to be a large obtuse angle of 120 degrees.

Description

Technical Field

[0001] The invention discloses a three-way ball valve for preventing crystallization of urea, which is used for three-way switching of a fluid production line and relates to the technical field of design and manufacturing of three-way reversing valves used in chemical production. Background Art

[0002] The three-way ball valve is a relatively new type of ball valve. It has some advantages unique to its structure, such as no friction when switching, the seal is not easy to wear, and the opening and closing torque is small. The use of a three-way ball valve can reduce the specifications of the actuator. If a multi-turn electric actuator is configured, it can also achieve regulation and strict shutoff of the medium. Therefore, the three-way ball valve is widely used in environments requiring strict shutoff, such as petroleum, chemical industry, and urban water supply and drainage.

[0003] The working principle of the three-way ball valve is to rotate the valve core to make the valve unblocked or blocked. The ball valve is easy to open and close, small in size, can be made into a large caliber, and has reliable sealing, simple structure, easy maintenance, the sealing surface and the spherical surface are often in a closed state, and are not easily eroded by the medium. It is widely used in various industries.

[0004] The three-way ball valve dedicated to urea production is installed at the top of the granulation tower of the urea outlet device. It is the last valve on the urea production line. Urine enters the granulation tower after passing through the urea three-way ball valve. The liquid is sprayed from high altitude and rapidly cooled to form white granular urea particles. Therefore, this valve is extremely important in the entire system. Urine begins to crystallize when the temperature is around 140°C. The temperature at this position just reaches the edge of crystallization. Therefore, it is difficult for many manufacturers' valves to avoid crystallization at this position. In addition, the basic insulation measure of manufacturers is to use steam pipes, wrap the steam pipes around the valve body for several turns, and pass the steam pipes through the valve body. Steam is added for insulation, but the insulation effect is not good. Once the production medium crystallizes, the valve body, ball, and valve seat are prone to jamming, seriously affecting the normal operation of the entire device. Because this valve is extremely important, many chemical companies choose imported brands, but imported brands are not only expensive and have slow delivery, but also may get stuck due to crystallization. Some companies also choose T-type three-way ball valves for simple processing and production. Since the flow channel of the T-type three-way ball valve is designed to be 90 degrees, it is easier to form crystals of the medium. Therefore, the use of T-type three-way ball valves will seriously affect long-term operation.

[0005] A medical anti-crystallization three-way reversing valve with announcement number CN212899888U includes a valve body with three medium inlets and outlets, a rotatable valve core connected to the lower end of the valve stem, two or three medium flow channels are provided in the valve core and the three medium inlets and outlets of the valve body are switched correspondingly, a sealing soft bushing is filled in the gap space between the outer surface of the valve core and the inner cavity of the valve body, the side wall of the sealing soft bushing is provided with three openings corresponding to the three medium inlets and outlets of the valve body, and the sealing soft bushing and the valve core are dynamically sealed. The utility model is a special valve used in the field of pharmaceutical production, does not have the anti-crystallization feature, and is therefore not suitable for use in urea production lines. Utility Model Content

[0006] The object of the present invention is to provide a three-way ball valve for preventing crystallization specially used in urea production, which can effectively solve the effect of preventing crystallization of the valve on the crystallization production line and achieve long-term online safe operation;

[0007] The urea-specific anti-crystallization three-way ball valve of the present invention comprises a three-way flow channel, a valve stem mechanism, a valve body and an actuator;

[0008] The three-way flow channel includes hexagonal nuts and bolts, a metal wound gasket, a valve seat, a valve body, a valve cover, and a ball. The three-way flow channel includes an inlet flow channel, a first outlet flow channel, and a second outlet flow channel;

[0009] The three flow channels of the three-way flow channel formed by the inlet flow channel, the first outlet flow channel and the second outlet flow channel are evenly divided into 360°, and the included angle of each flow channel is a large obtuse angle of 120°; the spherical surface of the sphere is matched with the three flow channels and is set to a large obtuse angle of 120°;

[0010] The three valve covers are all provided with sealing grooves on one side facing the sphere, and the valve seats are embedded in the sealing grooves provided on the valve covers;

[0011] The valve seat is made of polytetrafluoroethylene material;

[0012] The diameter of the sealing groove on the valve cover is larger than the diameter of the valve seat, and the thickness of the valve seat is larger than the depth of the sealing groove;

[0013] The valve body is provided with a steam flow channel inlet, a heat preservation chamber under the valve body, a steam flow channel, a heat preservation chamber on the valve body and a steam flow channel outlet;

[0014] The valve stem mechanism includes a valve stem, a packing, a hexagonal bolt, a washer, a hexagonal nut, a split nut, a bracket, and a connecting block. A step is provided between the connecting ball and the valve seat, and a packing is provided on the upper end surface of the step.

[0015] A bracket is arranged at the upper end of the valve seat, and a split nut and a connecting block are arranged in the bracket; the valve stem is assembled from the inside of the valve body to the outside, and the top diameter of the valve stem is larger than the outer diameter of the packing;

[0016] The valve stem is symmetrically provided with a packing at each of the upper and lower ends, and a gasket is provided at the upper end of the packing;

[0017] The actuator is mounted on the top end of the valve stem via a connecting block.

[0018] The beneficial effects of the utility model are as follows:

[0019] 1. In the utility model, the three flow channels of the three-way flow channel composed of the inlet flow channel, the first outlet flow channel and the second outlet flow channel are evenly divided into 360°, and the flow channel angle is a large obtuse angle of 120°, which can achieve smooth flow of the medium; the spherical flow channel is set to a large obtuse angle of 120°, and the flow channel has a smooth transition, which can be well matched with the three flow channels of the three-way flow channel.

[0020] 2. In the utility model, the diameter of the sealing groove arranged on the valve cover is larger than the diameter of the valve seat, and the thickness of the valve seat is larger than the depth of the sealing groove. Since the valve seat is made of polytetrafluoroethylene material and has a certain compressibility, when the valve seat is pressed tightly by the bolts, the valve seat will be squeezed into the sealing groove, which can not only play a sealing role, but also protect the sealing surface of the valve seat from being damaged by the medium.

[0021] 3. In the utility model, the steam used for heat preservation enters the heat preservation chamber at the lower part of the valve body through the steam flow channel inlet, then reaches the heat preservation chamber at the upper part of the valve body through three steam flow channels arranged on the valve body, and finally flows out through the steam flow channel outlet. The steam continuously flows inside the valve body to form a cycle, which can achieve the best heat preservation effect and prevent the medium from crystallizing.

[0022] 4. In the utility model, the valve stem is assembled from the inside of the valve body to the outside, and the diameter of the top end of the valve stem is larger than the outer diameter of the packing, which can effectively prevent the valve stem from being ejected when subjected to the pressure of the medium. When the valve stem is installed in the valve body, since a packing is symmetrically installed at the upper and lower ends, and a gasket is installed at the upper end of the packing, it can be prevented from generating a rotational force when tightening the hexagonal nut, thereby preventing the sealing performance of the packing from being destroyed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the assembly structure;

[0024] Figure 2 It is a schematic diagram of the cross-sectional structure of the three-channel assembly;

[0025] Figure 3 for Figure 2 Schematic diagram of the enlarged structure of Figure No. 16, 17, 18;

[0026] Figure 4 for Figure 1 Schematic diagram of the enlarged structure in circle A.

[0027] In the figure:

[0028] Hexagon nuts and bolts-01, metal wound gasket-02, valve seat-03, valve body-04, steam flow channel inlet-401, valve body lower insulation chamber-402, steam flow channel-403, valve body upper insulation chamber-404, steam flow channel outlet-405, valve cover-05, ball-06, valve stem-07, packing-08, hexagon head bolts-09, washers-10, hexagon nuts-11, split nuts-12, brackets-13, connecting blocks-14, actuators-15, inlet flow channel-16, first outlet flow channel-17, second outlet flow channel-18. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the utility model clearer, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments.

[0030] Therefore, based on the embodiments of the present utility model, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of the present utility model.

[0031] Example 1

[0032] See attached Figure 1-4 The urea-specific anti-crystallization three-way ball valve of the present invention comprises a three-way flow channel, a valve stem mechanism, a valve body and an actuator, wherein the three-way flow channel comprises a hexagonal nut and bolt 01, a metal winding gasket 02, a valve seat 03, a valve body 04, a valve cover 05 and a sphere 06; the three-way flow channel is assembled by a valve body 04, three valve covers 05 and a sphere 06, and the three-way flow channel comprises an inlet flow channel 16, a first outlet flow channel 17 and a second outlet flow channel 18. In order to achieve smooth flow of the medium, the three-way flow channel composed of the inlet flow channel 16, the first outlet flow channel 17 and the second outlet flow channel 18 is evenly divided into 360°, and the angle of each flow channel is a large obtuse angle of 120°. The spherical surface of the sphere 06 is also set to a large obtuse angle of 120° according to the flow channel, maintaining a smooth transition between the spherical surface and the flow channel, so as to achieve smooth coordination with the three-way flow channel.

[0033] See attached Figure 1 , 23. The valve seat 03 is made of polytetrafluoroethylene material, which can effectively protect the valve seat 03 and enhance the strength of the valve seat, ensuring the sealing performance of the valve; the three valve covers 05 are all provided with sealing grooves at one end facing the sphere 06, and the valve seat 03 is embedded in the sealing grooves provided on the valve covers 05; since the diameter of the sealing groove provided on the valve covers 05 is larger than the diameter of the valve seat 03, the thickness of the valve seat 03 is larger than the depth of the sealing groove, and since the valve seat 03 is made of polytetrafluoroethylene material and has a certain compressibility, when the installed valve covers 05 press the valve seat 03 under the tight pressure of the bolts, the valve seat 03 will be squeezed into the sealing groove, so that it can not only play a sealing role, but also protect the sealing surface of the valve seat 03 from being damaged by the medium;

[0034] See attached Figure 1 , 2 4: For the purpose of heat preservation, a steam flow channel inlet 401, a heat preservation chamber 402 under the valve body, a steam flow channel 403, a heat preservation chamber 404 on the valve body and a steam flow channel outlet 405 are provided on the valve body 04. The heat preservation steam enters the heat preservation chamber 402 at the lower part of the valve body through the steam flow channel inlet 401, and then reaches the heat preservation chamber 404 at the upper part of the valve body through the three steam flow channels 403 provided on the valve body 04, and finally flows out through the steam flow channel outlet 405. The steam continuously flows inside the valve 04 to form a cycle, which can achieve the best heat preservation effect and prevent the medium from crystallizing.

[0035] See attached Figure 1 , 4 The valve stem mechanism includes a valve stem 07, a packing 08, a hexagonal bolt 09, a washer 10, a hexagonal nut 11, a split nut 12, a bracket 13, and a connecting block 14. A step is provided between the connecting ball 06 and the valve seat 04, and a packing 08 is provided on the upper end surface of the step for sealing; a bracket 13 is provided at the upper end of the valve body 04, and a split nut 12 and a connecting block 14 are provided in the bracket 13; the valve stem 07 is assembled from the inside of the valve body 04 to the outside, and the top diameter of the valve stem 07 is larger than the outer diameter of the packing 08, which can effectively prevent the valve stem from being ejected when subjected to the pressure of the medium;

[0036] When the valve stem 07 is installed into the valve body 04, a packing 08 is symmetrically installed at the upper and lower ends, and a gasket 10 is installed at the upper end of the packing 08. The gasket 10 can prevent the rotation force generated when the hexagonal nut 11 is tightened, thereby destroying the sealing performance of the packing 08;

[0037] Specifically, when the hexagonal nut 11 is tightened, the packings 08 at the upper and lower ends are compressed. The fewer the packings 08 are, the smaller the friction is, and the less likely it is to get stuck. An actuator 15 is installed at the top of the valve stem 07. The actuator 15 is the actuator of the three-way ball valve and is connected and installed by the connecting block 14. The actuator 15 can be pneumatic, electric, or a combination of manual and pneumatic or electric. It should be noted that the actuator is not the key point of the present invention. The structure and control method of the actuator are easily conceivable by ordinary technicians in this technical field, so they are not described in detail here.

Claims

1. A three-way ball valve for preventing crystallization of urea, characterized by: It includes a three-way flow channel, a valve stem mechanism, a valve body and an actuator; The three-way flow channel comprises a hexagonal nut and a bolt (01), a metal wound gasket (02), a valve seat (03), a valve body (04), a valve cover (05), and a ball (06); the three-way flow channel comprises an inlet flow channel (16), a first outlet flow channel (17), and a second outlet flow channel (18); The three flow channels of the three-way flow channel formed by the inlet flow channel (16), the first outlet flow channel (17) and the second outlet flow channel (18) are evenly divided into 360°, and the angle of each flow channel is a large obtuse angle of 120°; the spherical surface of the sphere (06) cooperates with the three flow channels and is set to a large obtuse angle of 120°.

2. The urea-specific anti-crystallization three-way ball valve according to claim 1, characterized in that: The three valve covers (05) are all provided with sealing grooves on the side facing the sphere (06), and the valve seat (03) is embedded in the sealing grooves provided on the valve covers (05).

3. The urea-specific anti-crystallization three-way ball valve according to claim 1, characterized in that: The valve seat (03) is made of polytetrafluoroethylene material.

4. The urea-specific anti-crystallization three-way ball valve according to claim 1, characterized in that: The diameter of the sealing groove on the valve cover (05) is larger than the diameter of the valve seat (03), and the thickness of the valve seat (03) is larger than the depth of the sealing groove.

5. The urea-specific anti-crystallization three-way ball valve according to claim 1, characterized in that: The valve body (04) is provided with a steam flow channel inlet (401), a valve body lower insulation chamber (402), a steam flow channel (403), a valve body upper insulation chamber (404) and a steam flow channel outlet (405).

6. The urea-specific anti-crystallization three-way ball valve according to claim 1, characterized in that: The valve stem mechanism comprises a valve stem (07), a packing (08), a hexagonal bolt (09), a washer (10), a hexagonal nut (11), a split nut (12), a bracket (13), and a connecting block (14); a step is provided between the ball (06) and the valve seat (03); and a packing (08) is provided on the upper end surface of the step; A bracket (13) is arranged at the upper end of the valve body (04), and a split nut (12) and a connecting block (14) are arranged inside the bracket (13); the valve stem (07) is assembled from the inside of the valve body (04) to the outside, and the top diameter of the valve stem (07) is larger than the outer diameter of the packing (08).

7. The urea-specific anti-crystallization three-way ball valve according to claim 1, characterized in that: A packing (08) is symmetrically mounted on the upper and lower ends of the valve stem (07), and a gasket (10) is mounted on the upper end of the packing (08).

8. The urea-specific anti-crystallization three-way ball valve according to claim 1, characterized in that: It also includes an actuator (15), which is installed on the top end of the valve stem (07) through a connecting block (14).

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