Opening and closing deflection forced cut-off sealing structure of symmetrical double-hemisphere structure and sealing ball valve

Abstract

The invention relates to the field of ball valves, in particular to an opening and closing deflection forced cut-off sealing structure of a symmetrical double-hemisphere structure and a sealing ball valve. The opening and closing deflection forced cut-off sealing structure of the symmetrical double-hemisphere structure comprises a valve body, two valve seats, a rotating shaft and a ball core, the two valve seats are symmetrically installed in a valve cavity of the valve body, and the sealing surfaces are spherical curved surfaces; the rotating shaft is rotationally mounted in the valve body; the ball core comprises two buckled hemisphere structures, the two hemisphere structures are rotationally installed on the rotating shaft, and the matching faces, used for being attached to the sealing faces, of the hemisphere structures are also spherical curved faces; and the hemispherical structure is configured to rotate around the rotating shaft until the matching surface of the hemispherical structure is in surface contact with the sealing surface of the corresponding valve seat. The height difference between the spherical center of the matching surface of the hemispherical structure and the spherical center of the sealing surface of the valve seat in a closed state is reasonably set, so that the matching surface of the hemispherical structure can be better matched with the sealing surface of the valve seat, surface contact is formed, and the sealing performance of the ball valve during closing is improved.

Description

Technical Field

[0001] The invention relates to the field of ball valves, and in particular to a symmetrical double-hemispherical structure opening and closing deflection forced cutting sealing structure and a sealing ball valve. Background Art

[0002] The double hemisphere structure sealed ball valve has a double hemisphere structure for its ball core. During the opening process of this ball valve, the two double hemisphere structures are first closed, and then rotated until the ball core flow channel is aligned with the valve body flow channel; during the closing process, the two hemisphere structures are first rotated until the ball core flow channel is perpendicular to the valve body flow channel, and then opened and contacted with the valve seat to achieve sealing. For example, the patent with application number CN201120165746.X and the name of the patent is track-type two-way hard-sealed ball valve, which is this kind of sealed ball valve. This sealed ball valve can make the ball core rotate without contacting the valve seat and friction.

[0003] However, in this type of ball valve, when the hemispherical structure of the ball core rotates toward the corresponding valve seat until it abuts against the corresponding valve seat, there is line contact between the ball core and the valve seat. Even if the valve seat is squeezed, the contact area between the ball core and the valve seat is very small, resulting in a poor sealing effect. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a symmetrical double-hemispherical structure opening and closing deflection forced cut-off sealing structure, which reasonably sets the height difference between the center of the hemispherical structure mating surface and the center of the valve seat sealing surface in the closed state, so that the hemispherical structure mating surface can better match the valve seat sealing surface to form surface contact, thereby improving the sealing performance of the ball valve when it is closed.

[0005] In order to solve the above technical problems, the technical solution of the present invention is: a symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure, comprising:

[0006] Valve body;

[0007] Two valve seats are symmetrically mounted in the valve cavity of the valve body, and the sealing surfaces are spherical curved surfaces;

[0008] A rotary shaft, rotatably mounted in the valve body;

[0009] The ball core comprises two buckled hemispherical structures, the two hemispherical structures are respectively rotatably mounted on the rotary shaft, and the mating surfaces of the hemispherical structures for the sealing surface to be attached are also spherical curved surfaces; wherein,

[0010] When the two hemispherical structures are closed, the center of the mating surface of each hemispherical structure is higher than the center of the sealing surface of the corresponding valve seat by h. The calculation formula for h is:

[0011]

[0012] Wherein, L is the horizontal distance between the center of the mating surface of each hemispherical structure and the center of the sealing surface of the corresponding valve seat when the two hemispherical structures are closed, and H is the vertical distance between the center of the rotary shaft and the center of the sealing surface of the valve seat.

[0013] Furthermore, the radius of the matching surface of the hemispherical structure is equal to the radius of the sealing surface of the corresponding valve seat.

[0014] In order to further reduce the rotational torque of the ball core, the rotary shaft is rotatably mounted in the valve body through a thrust needle roller bearing, and the thrust needle roller bearing is mounted at the bottom of the valve body; wherein,

[0015] The lower halves of the two ends of the rotating shaft are respectively provided with contact planes, and the contact planes are placed on the support pads of the thrust needle roller bearing. The part of the rotating shaft located between the two contact planes extends downward beyond the contact planes and is stuck in the center hole of the support pad.

[0016] Furthermore, the support pad is a hardened and ground gasket.

[0017] Furthermore, a sliding bearing is installed at the inner bottom of the valve body, and the thrust needle roller bearing is installed in the sliding bearing.

[0018] Furthermore, after the mating surface of the hemispherical structure is in contact with the sealing surface of the corresponding valve seat, it completely covers the sealing surface of the corresponding valve seat.

[0019] The present invention also relates to a sealing ball valve, comprising:

[0020] Symmetrical double hemisphere structure opening and closing deflection forced cutting off sealing structure;

[0021] A valve cover is installed on the top of the valve body of the symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure;

[0022] The rotary push mechanism is installed on the valve cover and cooperates with the ball core of the symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure to drive the ball core to rotate and open and close.

[0023] After adopting the above technical solution, the present invention calculates and designs the height difference h between the center of the mating surface of each hemispherical structure and the center of the sealing surface of the corresponding valve seat when the two hemispherical structures are closed, so that the mating surface of the ball core can be completely fitted with the sealing surface of the valve seat when the ball core is closed, so that the sealing performance of the valve is better when it is closed, and the service life of the valve seat is extended at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the internal structure of the symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure of the present invention;

[0025] Figure 2 This is a comparison diagram of the two hemisphere structures of the core of the invention in a closed state (initial position) and an open state (sealed state position);

[0026] Figure 3 for Figure 1 A magnified view of part A;

[0027] Figure 4 for Figure 1 A magnified view of part B;

[0028] Figure 5 It is a result schematic diagram of the rotary shaft of the present invention;

[0029] Figure 6 It is a schematic diagram of the internal structure of the sealing ball valve of the present invention;

[0030] In the figure, 1, valve body; 11, valve chamber; 2, valve seat; 21, sealing surface; 3, rotary shaft; 31, contact plane; 4, hemispherical structure; 41, mating surface; 5, thrust needle roller bearing; 51, support pad; 6, mating shaft; 7, sliding bearing; 8, valve cover; 81, middle valve cover; 82, upper valve cover; 9, rotary push mechanism; 91, valve stem; 92, transmission part; 921, track slide groove; 93, track slider. DETAILED DESCRIPTION

[0031] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0032] Embodiment 1

[0033] like Figures 1 to 6 As shown, a symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure comprises:

[0034] Valve body 1;

[0035] Two valve seats 2 are symmetrically mounted in the valve cavity 11 of the valve body 1, and the sealing surface 21 is a spherical curved surface;

[0036] A rotary shaft 3 is rotatably mounted in the valve body 1;

[0037] The ball core includes two buckled hemispherical structures 4, which are rotatably mounted on the rotary shaft 3 respectively, and the mating surface 41 of the hemispherical structure 4 for the sealing surface 21 to fit is also a spherical curved surface;

[0038] The hemispherical structure 4 is configured to be rotatable around the rotary axis 3 until its mating surface 41 is in surface contact with the sealing surface 21 of the corresponding valve seat 2 .

[0039] In this embodiment, the hemispherical structure 4 is rotated until its mating surface 41 is in surface contact with the sealing surface 21 of the corresponding valve seat 2, that is, it is rotated to Figure 2 (b) shows the open state (sealed state position), at this time, the ball core of the mating surface of the hemispherical structure 4 and the ball core of the sealing surface 21 of the valve seat 2 are coincident. Figure 2 (a) is in the closed state (initial position) and rotated to Figure 2 (b) in the open state (sealed state position), the center of the ball will move downward. Therefore, when the two hemispherical structures 4 are closed, the height difference h between the center of the sphere of the matching surface 41 of each hemispherical structure 4 and the center of the sphere of the sealing surface 21 of the corresponding valve seat 2 is used as the compensation leveling amount. The calculation formula of h can be:

[0040]

[0041] Wherein, L is the horizontal distance between the center of the mating surface 41 of each hemispherical structure 4 and the center of the sealing surface 21 of the corresponding valve seat 2 when the two hemispherical structures 4 are closed, and H is the vertical distance between the center of the rotary shaft 3 and the center of the sealing surface 21 of the valve seat 2.

[0042] It should be noted that the hemispherical structure 4 and the mating surface 41 thereon are arranged concentrically, and the radius of the mating surface 41 can be larger than the radius of the hemispherical structure 4. The two hemispherical structures 4 rotate around the axis of the rotating shaft 3 respectively. Figure 2 The letter R in denoted the rotation radius of the center of the hemispherical structure 4 and the matching surface 41 .

[0043] Specifically, this embodiment calculates and designs the height difference h between the center of the mating surface 41 of each hemispherical structure 4 and the center of the sealing surface 21 of the corresponding valve seat 2 when the two hemispherical structures 4 are closed, so that the mating surface 41 of the ball core can be completely in contact with the sealing surface 21 of the valve seat 2 when closed, thereby improving the sealing performance of the valve when closed and extending the service life of the valve seat 2.

[0044] In this embodiment, in order to make the mating surface 41 of the hemispherical structure 4 better match the sealing surface 21 of the corresponding valve seat 2, the radius of the mating surface 41 of the hemispherical structure 4 is equal to the radius of the sealing surface 21 of the corresponding valve seat 2. Of course, considering that the valve seat 2 can be deformed to a certain extent, it is also possible that the radius of the sealing surface 21 of the valve seat 2 is slightly smaller than the radius of the mating surface 41 of the hemispherical structure 4.

[0045] In this embodiment, the width of the mating surface 41 of the hemispherical structure 4 is greater than or equal to the width of the sealing surface 21 of the valve seat 2, and preferably greater than the width of the sealing surface 21 of the valve seat 2. Moreover, after the mating surface 41 of the hemispherical structure 4 is attached to the sealing surface 21 of the valve seat 2, it completely covers the sealing surface 21 of the valve seat 2.

[0046] Embodiment 2

[0047] Based on the first embodiment, Figure 1 , Figure 4 and Figure 6 As shown, the rotary shaft 3 is rotatably mounted in the valve body 1 through the thrust needle roller bearing 5, and the thrust needle roller bearing 5 is mounted at the bottom of the valve body 1; wherein,

[0048] like Figure 5 As shown, the lower halves of the two ends of the rotating shaft 3 are respectively provided with contact planes 31, which are placed on the support pads 51 of the thrust needle roller bearing 5. The portion of the rotating shaft 3 located between the two contact planes 31 extends downward beyond the contact planes 31 and is inserted into the center hole of the support pad 51.

[0049] The thrust needle roller bearing 5 has two support pads 51, one on the top and one on the bottom. The support pads 51 are thicker than the support pads 51 of the conventional thrust needle roller bearing 5. The support pads 51 are used to raise the ball core. By adjusting the thickness of the support pads 51, the hemispherical structure 4 can rotate to Figure 2 When in the open state (sealed state position) of (b), the center of the sphere of the mating surface 41 can coincide with the center of the sphere of the sealing surface 21, and the mating surface 41 fits well with the sealing surface 21 to achieve surface-to-surface contact sealing.

[0050] Specifically, the thrust needle roller bearing 5 can significantly reduce the rotation torque of the ball core during the rotation process, and avoid dry grinding between the ball core or the rotary shaft 5 and the valve body 1. In addition, by reasonably designing the structure of the rotary shaft 3, the rotary shaft 3 can be used in conjunction with the thrust needle roller bearing 5, and the thrust needle roller bearing 5 can be made as large as possible, with better and more uniform force.

[0051] In this embodiment, the support pad 51 is preferably a hardened and ground pad. After the hardened pad is precisely ground, the surface is smoother, the thrust needle roller bearing 5 is more stable during operation, the damping is smaller, and it can withstand the deadweight of the ball core and the downward thrust of the valve stem 91 when the valve is closed.

[0052] In this embodiment, a sliding bearing 7 may be installed at the bottom of the valve body 1, and the thrust needle roller bearing 5 is installed in the sliding bearing 7. In this way, the rotation resistance of the support pad 51 at the upper end of the thrust needle roller bearing 5 can be further reduced.

[0053] Embodiment 3

[0054] like Figures 1 to 6 As shown, a sealing ball valve comprises:

[0055] The symmetrical double hemisphere structure in the first or second embodiment opens and closes and deflects to forcibly cut off the sealing structure;

[0056] The valve cover 8 is mounted on the top of the valve body 1 of the symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure;

[0057] The rotary push mechanism 9 is installed on the valve cover 8 and cooperates with the ball core of the symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure to drive the ball core to rotate and open and close.

[0058] Among them, Figure 6 As shown, the valve cover 8 may include a middle valve cover 81 and an upper valve cover 82 . The middle valve cover 81 is mounted on the upper end of the valve body 1 , and the upper valve cover 82 is mounted on the upper end of the middle valve cover 81 .

[0059] like Figure 6 As shown, the rotary push mechanism 9 includes a valve stem 91, a transmission member 92 and a track slider 93. The valve stem 91 can be slidably installed in the valve cover 8. The transmission member 92 is rotatably connected to the valve stem 91. The transmission member 92 is provided with a track slide 921. The track slide 921 includes a vertical groove in the upper part and a spiral groove in the lower part. The track slider 93 is fixedly installed on the valve cover 8. The two hemispherical structures 4 are respectively provided with two matching shafts 6. The transmission member 92 is also provided with two symmetrical sliding parts. Each sliding part is slidably matched with the corresponding hemispherical structure 4 up and down. The sliding part includes a vertical part located at the bottom and an inclined part located at the top. Each inclined part has an inner inclined surface and an outer inclined surface that are inclined outward from bottom to top. The two configuration shafts 6 of each hemispherical mechanism 4, one is in contact with the inner inclined surface of the corresponding inclined surface, and the other is in contact with the outer inclined surface of the corresponding inclined surface.

[0060] The process of the entire rotary push mechanism 9 closing the ball valve is:

[0061] The valve stem 91 pushes the transmission member 92 to move downward, and the transmission member 92 first moves downward and rotates in cooperation with its spiral groove and the track slider 93, and drives the ball core to rotate through its vertical portion until the ball core flow channel and the valve body 1 flow channel are vertically arranged at 90 degrees. Then, it only moves downward in cooperation with its vertical groove and the track slider 93, and pushes the corresponding mating shaft 6 through the outer inclined surface of its inclined portion, so that the two hemispherical structures 4 rotate toward the corresponding valve seat 2 side to open, until the mating surface of the hemispherical structure 4 is in surface contact with the sealing surface 21 of the valve seat 2 to achieve sealing.

[0062] The process of the entire rotary push mechanism 9 opening the ball valve is:

[0063] The valve stem 91 drives the transmission member 92 to move upward. The transmission member 92 first moves upward with the cooperation of its vertical groove and the track slider 93, and pushes the two hemispherical structures 4 to rotate back to the corresponding valve seats 2 to close through its inner inclined surface. Then, with the cooperation of its spiral groove and the track slider 93, it moves upward while rotating, and drives the ball core through its vertical part to rotate until the ball core flow channel is aligned with the valve body 1 flow channel, and the entire opening process is completed.

[0064] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure, characterized in that: include: Valve body (1); Two valve seats (2) are symmetrically mounted in the valve cavity (11) of the valve body (1), and the sealing surfaces (21) are spherical curved surfaces; A rotary shaft (3) rotatably mounted in the valve body (1); The ball core comprises two buckled hemispherical structures (4), the two hemispherical structures (4) are respectively rotatably mounted on the rotary shaft (3), and the matching surface (41) of the hemispherical structure (4) for abutting the sealing surface (21) is also a spherical curved surface; wherein: When the two hemispherical structures (4) are closed, the center of the matching surface (41) of each hemispherical structure (4) is higher than the center of the sealing surface (21) of the corresponding valve seat (2) by a factor h. The calculation formula for h is: Wherein, L is the horizontal distance between the center of the mating surface (41) of each hemispherical structure (4) and the center of the sealing surface (21) of the corresponding valve seat (2) when the two hemispherical structures (4) are closed, and H is the vertical distance between the center of the rotary shaft (3) and the center of the sealing surface (21) of the valve seat (2).

2. The symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure according to claim 1 is characterized in that: The radius of the matching surface (41) of the hemispherical structure (4) is equal to the radius of the sealing surface (21) of the corresponding valve seat (2).

3. The symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure according to claim 1 is characterized in that: The rotary shaft (3) is rotatably mounted in the valve body (1) via a thrust needle roller bearing (5), and the thrust needle roller bearing (5) is mounted at the bottom of the valve body (1); wherein: The lower halves of the two ends of the rotary shaft (3) are respectively provided with contact planes (31), and the contact planes (31) are placed on the support pads (51) of the thrust needle roller bearing (5). The portion of the rotary shaft (3) located between the two contact planes (31) extends downward beyond the contact planes (31) and is inserted into the center hole of the support pad (51).

4. The symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure according to claim 1 is characterized in that: The support pad (51) is a hardened and ground pad.

5. The symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure according to claim 3 is characterized in that: A sliding bearing (7) is installed at the bottom of the valve body (1), and the thrust needle roller bearing (5) is installed in the sliding bearing (7).

6. The symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure according to claim 1 is characterized in that: After the mating surface (41) of the hemispherical structure (4) is in contact with the sealing surface (21) of the corresponding valve seat (2), it completely covers the sealing surface (21) of the corresponding valve seat (2).

7. A sealed ball valve, characterized in that: include: The symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure as described in any one of claims 1 to 6; A valve cover (8) is mounted on the top of the valve body (1) of the symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure; The rotary push mechanism (9) is installed on the valve cover (8) and cooperates with the ball core of the symmetrical double hemisphere structure opening and closing deflection forced cutting sealing structure to drive the ball core to rotate and open and close.

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