Butterfly valve with soft and hard double-sealing structure

Abstract

According to the technical scheme, the butterfly valve is characterized by comprising a butterfly plate and a valve seat which can form sealing mutually, the butterfly plate comprises a bottom plate connected with a valve rod, a cover plate covering the bottom plate, and a sealing set limited between the bottom plate and the cover plate and capable of being attached to the valve seat, the sealing group comprises a plurality of soft sealing rings and hard sealing rings which are alternately arranged, the plurality of soft sealing rings are provided with a plurality of through holes which take the axis of the butterfly plate as the center and are circumferentially distributed, and the two end surfaces of the plurality of hard sealing rings are respectively provided with ejector rods which can penetrate through the through holes in a one-to-one correspondence manner and limiting grooves into which the end parts of the ejector rods can be inserted; the cover plate and the bottom plate jointly clamp the sealing set so that the ejector rods can abut against the groove bottoms of the corresponding limiting grooves, and the problems that in the prior art, the sealing effect is poor, and opening and closing are difficult are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of butterfly valves, and more particularly to a butterfly valve with a soft and hard double sealing structure. Background Art

[0002] The existing butterfly valve sealing design between the butterfly plate and the valve seat mostly adopts soft and hard sealing, that is, a plurality of soft sealing rings and hard sealing rings are arranged alternately at the edge of the butterfly plate and the outer wall of the soft sealing ring can be tightly attached to the valve seat. For example, the Chinese patent publication number CN219510150U discloses a fluorine-lined butterfly valve with a multi-layer stainless steel sheet sealing ring. The soft sealing ring used is a rubber sheet and the hard sealing ring is a stainless steel sheet. Although the soft and hard double seal can effectively improve the sealing between the butterfly plate and the valve seat, it still has defects. The elastic deformation ability of the multiple clamped soft sealing rings is different, resulting in each soft sealing ring being relatively The extended lengths in the diameter direction of the butterfly plate are different. The edges of some soft sealing rings are raised relative to the edges of the adjacent hard sealing rings, and the edges of some soft sealing rings are recessed relative to the edges of the adjacent hard sealing rings. This will cause the overall edge surfaces of the soft and hard sealing rings to be uneven, resulting in increased friction when the butterfly plate is screwed in or out of the valve seat, requiring greater torque and reduced sealing effect between the butterfly plate and the valve seat. Furthermore, there are machining errors in the inner diameters of the hard and soft sealing rings, which cause them to move radially relative to the butterfly plate. This will further aggravate the unevenness of the overall circumferential wall surface of the sealing ring, further affecting the sealing performance and opening and closing efficiency. Utility Model Content

[0003] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a butterfly valve which is easy to open and close, has a smooth sealing surface and a stable sealing effect.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a butterfly valve with a soft and hard double sealing structure, comprising a butterfly plate and a valve seat that can form a seal with each other, the butterfly plate comprising a bottom plate connected to the valve stem, a cover plate covering the bottom plate, and a sealing group limited between the bottom plate and the cover plate and capable of fitting with the valve seat, the sealing group comprising a plurality of soft sealing rings and hard sealing rings arranged alternately, the plurality of soft sealing rings are each provided with a plurality of through holes centered on the axis of the butterfly plate and distributed in a circular pattern, the two end faces of the plurality of hard sealing rings are respectively provided with push rods that can pass through the through holes in a one-to-one correspondence and limiting grooves for inserting the ends of the push rods, the sealing group is clamped together by the cover plate and the bottom plate so that the push rods touch the bottom of the corresponding limiting grooves.

[0005] As a further improvement of the present invention, the number of the hard sealing rings is equal to the number of the soft sealing rings, the bottom plate is in close contact with the adjacent soft sealing rings and is provided with a bottom groove having the same structure as the limiting groove.

[0006] As a further improvement of the present invention, the number of the hard sealing rings is greater than the number of the soft sealing rings, and the bottom plate is provided with grooves for accommodating the top rods of adjacent hard sealing rings.

[0007] As a further improvement of the present invention, the number of the hard sealing rings is less than the number of the soft sealing rings, the bottom plate is provided with a bottom rod having the same structure as the top rod and capable of passing through adjacent soft sealing rings, and the cover plate is provided with a cover groove for accommodating the end of the top rod.

[0008] As a further improvement of the present invention, the end edges of the push rod are chamfered.

[0009] The beneficial effects of the present invention are as follows: the cover plate and the bottom plate jointly clamp the sealing group so that the push rod touches the bottom of the corresponding limit groove. Compared with the existing technology, this design makes the push rod touch the nearest hard sealing ring so that the soft sealing ring no longer deforms, ensuring that the deformations of multiple soft sealing rings are the same or similar, thereby ensuring that the sealing surfaces of the sealing group and the valve seat are kept flush, effectively improving the sealing stability between the valve seat and the sealing group; at the same time, it effectively compensates for the uneven sealing surface defects of the sealing group, and the friction force generated between the sealing group and the valve seat is within a reasonable range, which facilitates the smooth rotation of the butterfly plate relative to the valve seat and improves the opening and closing efficiency of the butterfly plate; further, the design of the push rod and the limit groove plug-in can ensure that the coaxiality of the two hard sealing rings with similar distances is high, and the push rod passes through the adjacent soft sealing rings, thereby ensuring that multiple hard sealing rings and multiple soft sealing rings are all on the same axis, further reducing the unevenness of the peripheral wall of the sealing group, and indirectly improving the sealing effect of the sealing group. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is the main sectional view of the utility model;

[0011] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0012] Figure 3 for Figure 2 State diagram when the number of medium-hard sealing rings is greater than that of soft sealing rings;

[0013] Figure 4 for Figure 2 State diagram when the number of medium-hard sealing rings is less than that of soft sealing rings;

[0014] Figure 5 for Figure 2 The diagram shows the state when no seal is formed with the valve seat and no cover is installed.

[0015] Figure numerals: 1, butterfly plate; 11, bottom plate; 111, bottom groove; 112, groove; 113, bottom rod; 12, cover plate; 121, cover groove; 13, sealing group; 14, soft sealing ring; 15, hard sealing ring; 16, through hole; 17, push rod; 18, limit groove; 2, valve seat. DETAILED DESCRIPTION

[0016] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments, wherein the same components are denoted by the same reference numerals.

[0017] Reference Figures 1 to 5 As shown, a butterfly valve with a soft and hard dual sealing structure of this embodiment includes a butterfly plate 1 and a valve seat 2 that can form a seal with each other. The butterfly plate 1 includes a base plate 11 connected to the valve stem, a cover plate 12 covering the base plate 11, and a sealing group 13 limited between the base plate 11 and the cover plate 12 and capable of affixing to the valve seat 2. The sealing group 13 includes a plurality of soft sealing rings 14 and hard sealing rings 15 arranged alternately.

[0018] Based on the above-mentioned prior art, multiple soft sealing rings 14 are each provided with multiple through holes 16 located on the same circumference and coaxial with the butterfly plate 1. A push rod 17 that can penetrate the through holes 16 and a limiting groove 18 for inserting the end of the push rod 17 are respectively processed on the two end faces of the multiple hard sealing rings 15. When the sealing group 13 is not tightened by the base plate 11 and the cover plate 12, the peripheral wall of the sealing group 13 is uneven, and the end of the push rod 17 extends into the corresponding limiting groove 18 and there is a gap with the bottom of the limiting groove 18. The quantitative relationship and assembly relationship between the soft sealing ring 14 and the hard sealing ring 15 are roughly the following three situations:

[0019] The first one is specific reference Figure 2 and Figure 5As shown, the number of hard sealing rings 15 is equal to the number of soft sealing rings 14, and the bottom plate 11 is provided with a bottom groove 111 with the same structure as the limit groove 18 and the same number as the top rod 17. Then, during the assembly process of the butterfly plate 1, the bottom plate 11 is laid flat on the ground, and then the soft sealing ring 14 is installed on the bottom plate 11 and the through hole 16 on the soft sealing ring 14 is correspondingly connected to the bottom groove 111. Then, one end face of the hard sealing ring 15 with the top rod 17 is fitted on the soft sealing ring 14, and multiple top rods 17 respectively pass through the corresponding through holes 16 and extend into the bottom groove 111. There is a gap between the end of the top rod 17 and the bottom of the bottom groove 111. Then, the remaining soft sealing rings 14 and hard sealing rings 15 are placed on the bottom plate 11 in turn, and multiple hard sealing rings 15 are placed on the bottom plate 11 in turn. The plurality of soft sealing rings 14 are stacked together, and the push rod 17 passes through the adjacent soft sealing ring 14 and extends into the limiting groove 18 of the nearest hard sealing ring 15. There is a gap between the push rod 17 and the bottom of the corresponding limiting groove 18. Finally, the cover plate 12 is covered on the bottom plate 11 and fixed together with bolts. The cover plate 12 and the bottom plate 11 are fully fitted with the adjacent soft sealing ring 14 and the hard sealing ring 15 respectively. The cover plate 12 and the bottom plate 11 jointly clamp the sealing group 13. Under the action of the extrusion force of the sealing group 13, the plurality of soft sealing rings 14 are elastically compressed and radially extended, and the thickness of the plurality of soft sealing rings 14 is reduced until the push rod 17 touches the bottom of the bottom groove 111 or the limiting groove 18 into which it is inserted, and then all the soft sealing rings 14 are no longer deformed.

[0020] Second, specific reference Figure 3 As shown, the number of hard sealing rings 15 is one more than the number of soft sealing rings 14, and the bottom plate 11 is provided with a groove 112 for accommodating the push rod 17 of the adjacent hard sealing ring 15. In the assembly process of the butterfly plate 1, the bottom plate 11 is laid flat on the ground, and then a hard sealing ring 15 is placed on the bottom plate 11 and the push rod 17 on the hard sealing ring 15 is inserted into the groove 112, and then the soft sealing ring 14 is placed on the aforementioned hard sealing ring 15 and the through hole 16 is connected to the limiting groove 18 accordingly, and then another hard sealing ring 15 is processed with an end face of the push rod 17 to fit on the aforementioned soft sealing ring 14, and multiple push rods 17 respectively pass through the corresponding through holes. The hole 16 is inserted into the limiting groove 18, and there is a gap between the end of the push rod 17 and the bottom of the limiting groove 18. Then, the remaining soft sealing rings 14 and the hard sealing rings 15 are placed on the bottom plate 11 in turn, so that multiple hard sealing rings 15 and multiple soft sealing rings 14 are superimposed together, and the cover plate 12 and the bottom plate 11 are fully fitted with the adjacent hard sealing rings 15 and clamp the sealing group 13. Under the action of the extrusion force of the sealing group 13, the multiple soft sealing rings 14 are elastically compressed and radially extended, and the thickness of the multiple soft sealing rings 14 is reduced until the push rod 17 touches the bottom of the limiting groove 18 into which it is inserted, and then all the soft sealing rings 14 are no longer deformed;

[0021] The third type, specific reference Figure 4 As shown, the number of hard sealing rings 15 is one less than the number of soft sealing rings 14, the bottom plate 11 is provided with a bottom rod 113 having the same structure as the top rod 17 and capable of passing through the adjacent soft sealing rings 14, and the cover plate 12 is provided with a cover groove 121 for accommodating the end of the top rod 17. During the assembly process of the butterfly plate 1, the bottom plate 11 is laid flat on the ground, and then the multiple through holes 16 of the soft sealing ring 14 are respectively sleeved on the outside of the multiple bottom rods 113, and then the hard sealing ring 15 and the remaining soft sealing rings 14 are placed on the bottom plate 11 in turn, so that the multiple hard sealing rings 15 and the multiple soft sealing rings 14 are stacked. Together, the end of the bottom rod 113 passes through the soft sealing groove 14 and extends into the limiting groove 18, and there is a gap with the bottom of the limiting groove 18. Finally, the cover plate 12 is covered on the bottom plate 11. The cover plate 12 and the bottom plate 11 are fully fitted with the adjacent soft sealing rings 14 respectively. The cover plate 12 and the bottom plate 11 jointly clamp the sealing group 13. Under the action of the extrusion force of the sealing group 13, the multiple soft sealing rings 14 are elastically compressed and radially extended, and the thickness of the multiple soft sealing rings 14 is reduced until the top rod 17 touches the bottom of the limiting groove 18 into which it is inserted, and then all the soft sealing rings 14 are no longer deformed.

[0022] Compared with the prior art, this design makes the soft sealing ring 14 no longer deformed by the push rod 17 contacting the nearest hard sealing ring 15, ensuring that the deformation of multiple soft sealing rings 14 is the same or similar, thereby ensuring that the sealing surface of the sealing group 13 and the valve seat 2 remain flush, effectively improving the sealing stability between the valve seat 2 and the sealing group 13; at the same time, it effectively compensates for the uneven sealing surface defect of the sealing group 13, and the friction force generated between the sealing group 13 and the valve seat 2 is within a reasonable range, which facilitates the smooth rotation of the butterfly plate 1 relative to the valve seat 2, improving the butterfly plate 1 The opening and closing efficiency is improved; furthermore, the design of the connection between the top rod 17 and the limiting groove 18 can ensure that the coaxiality of the two hard sealing rings 15 with a close distance is high, and the top rod 17 passes through the adjacent soft sealing ring 14, thereby ensuring that the multiple hard sealing rings 15 and the multiple soft sealing rings 14 are all on the same axis, further reducing the unevenness of the surrounding walls of the sealing group 13; the bottom groove 111, the groove 112 or the bottom rod 113 provided on the bottom plate 11 can improve the coaxiality between the sealing group 13 and the bottom plate 11, thereby indirectly improving the sealing effect of the sealing group 13.

[0023] As a specific embodiment of the improvement, refer to Figure 5 As shown, the end edges of the push rod 17 are chamfered. Such a design can improve the smoothness of the push rod 17 entering the corresponding limiting groove 18, bottom groove 111, groove 112 or cover groove 121 during assembly.

[0024] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, certain improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A butterfly valve with a soft and hard double sealing structure, comprising a butterfly plate (1) and a valve seat (2) capable of forming a seal with each other, the butterfly plate (1) comprising a base plate (11) connected to the valve stem, a cover plate (12) covering the base plate (11), and a sealing group (13) limited between the base plate (11) and the cover plate (12) and capable of affixing to the valve seat (2), the sealing group (13) comprising a plurality of soft sealing rings (14) and hard sealing rings (15) arranged alternately, characterized in that: The plurality of soft sealing rings (14) are each provided with a plurality of through holes (16) centered on the axis of the butterfly plate (1) and distributed in a circumferential manner. The two end faces of the plurality of hard sealing rings (15) are respectively provided with push rods (17) that can pass through the through holes (16) in a one-to-one correspondence and limit grooves (18) for inserting the ends of the push rods (17). The sealing group (13) is clamped together by the cover plate (12) and the bottom plate (11) so that the push rods (17) touch the bottom of the corresponding limit grooves (18).

2. A butterfly valve with a soft and hard double sealing structure according to claim 1, characterized in that: The number of the hard sealing rings (15) is equal to the number of the soft sealing rings (14); the bottom plate (11) is in close contact with adjacent soft sealing rings (14) and is provided with a bottom groove (111) having the same structure as the limiting groove (18).

3. The butterfly valve with a soft and hard double sealing structure according to claim 1, characterized in that: The number of the hard sealing rings (15) is greater than the number of the soft sealing rings (14), and the bottom plate (11) is provided with grooves (112) for accommodating the top rods (17) of adjacent hard sealing rings (15).

4. The butterfly valve with a soft and hard double sealing structure according to claim 1, characterized in that: The number of the hard sealing rings (15) is less than the number of the soft sealing rings (14); the bottom plate (11) is provided with a bottom rod (113) having the same structure as the top rod (17) and capable of penetrating adjacent soft sealing rings (14); and the cover plate (12) is provided with a cover groove (121) for accommodating the end of the top rod (17).

5. A butterfly valve with a soft and hard double sealing structure according to claim 1, 2, 3 or 4, characterized in that: The end edges of the push rod (17) are all chamfered.

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