High-temperature three-eccentric center butterfly valve with elastic compensation

Abstract

The high-temperature three-eccentric center butterfly valve comprises a valve body, a butterfly plate installed in the valve body, a valve rod arranged in the valve body in a penetrating mode and connected with the butterfly plate, a valve cover fixed to the top of the valve body and an end cover fixed to the bottom of the valve body, and a thrust washer is arranged at the bottom of the valve rod in a cushioned mode. The thrust washer is supported on the end cover, and a belleville spring is arranged between the thrust washer and the end cover. The thrust washer and the belleville spring are arranged, and elastic compensation is provided for movement of the valve rod through compression and extension of the belleville spring under different working conditions. Under the high-temperature working condition, when the valve rod is heated to extend, the belleville spring below the thrust washer can be extruded, a compensation space is reserved for thermal expansion, and the shaft end of the valve rod cannot be tightly ejected; under the normal temperature condition, the thrust washer can abut against the shaft end of the valve rod under the action of the belleville spring, the valve rod is kept at the stable relative position, and therefore it is guaranteed that the valve plate is vertically guided and fixed when the valve is opened and closed.

Description

Technical Field

[0001] The invention relates to the technical field of valves, and in particular to a high-temperature three-eccentric butterfly valve with elastic compensation. Background Art

[0002] The three-eccentric butterfly valve is a specially designed valve that achieves efficient fluid control through three eccentric designs (valve body, valve stem, valve seat). The sealing performance between the butterfly plate and the valve seat has been significantly improved, and the leakage rate is extremely low. The three-eccentric butterfly valve has a compact and light structure, strong corrosion resistance, strong fluid control ability, good adjustment performance, and high safety. It is widely used in chemical industry, heating, environmental protection, food and pharmaceutical, water treatment and other fields.

[0003] The high-temperature three-eccentric butterfly valve is suitable for high-temperature environments and can withstand high temperatures and pressures. It has excellent performance in fluid control. However, after the high-temperature three-eccentric butterfly valve is opened, under high-temperature conditions, the valve stem that first contacts the medium will be the first to expand due to heat. Since the valve stem and the disc plate are connected by pins and cannot move in series, the valve stem will expand and stretch to both ends, causing the valve stem shaft end to be squeezed and stuck, resulting in operational failures. Summary of the invention

[0004] The main purpose of the present invention is to provide a high-temperature three-eccentric butterfly valve with elastic compensation which can avoid the valve stem shaft end from being stuck.

[0005] To achieve the above-mentioned objectives, the present invention provides a high-temperature three-eccentric butterfly valve with elastic compensation, comprising a valve body, a disc plate installed in the valve body, a valve stem inserted in the valve body and connected to the disc plate, a valve cover fixed to the top of the valve body and an end cover fixed to the bottom of the valve body, a thrust washer is provided at the bottom of the valve stem, the thrust washer is supported on the end cover and a disc spring is provided between the thrust washer and the end cover.

[0006] Furthermore, a mounting groove is formed on the top surface of the end cover, and the thrust washer is located in the mounting groove.

[0007] Furthermore, a limiting groove is provided on the bottom wall of the installation groove, and a limiting block is provided at the bottom of the thrust washer, and the limiting block is clamped in the limiting groove.

[0008] Furthermore, a hardening layer is provided on the top surface of the thrust washer.

[0009] Furthermore, a thrust bearing is sleeved on the lower end of the valve stem, a first key groove is opened on the inner side of the bottom of the thrust bearing, a second key groove is opened at the lower end of the valve stem at a position corresponding to the first key groove, and connecting keys are installed in the first key groove and the second key groove.

[0010] Furthermore, the connecting key is in the shape of a flat, oval block.

[0011] Furthermore, the upper part of the valve stem is sequentially sleeved with a shaft spacer, a sealing ring and an upper bearing from top to bottom, the valve stem is partially hardened corresponding to the upper bearing, and an upper dust ring is provided between the lower end of the upper bearing and the valve stem.

[0012] Furthermore, a lower bearing is sleeved on the lower part of the valve stem, a portion of the valve stem corresponding to the lower bearing is hardened, and a lower dust ring is provided between the upper end of the lower bearing and the valve stem.

[0013] Furthermore, the hardening design is achieved by spraying or surfacing a hardening layer.

[0014] Furthermore, the valve cover is an elongated structure, and a packing pressure plate, a packing and a packing seat are sequentially sleeved between the valve stem and the valve cover from top to bottom. A circle of steps is opened on the upper inner circumference of the valve cover, and the packing pressure plate, the packing and the packing seat are located in the step.

[0015] The beneficial effects of the present invention are embodied in: The present invention provides elastic compensation for the movement of the valve stem by arranging a thrust washer and a disc spring, and by compressing and extending the disc spring under different working conditions. Under high temperature conditions, when the valve stem is heated and extended, the disc spring below the thrust washer will be squeezed, and the compensation space reserved for thermal expansion will not cause the valve stem shaft end to be stuck; under normal temperature conditions, the thrust washer will press the valve stem shaft end under the action of the disc spring, so that the valve stem maintains a stable relative position, thereby ensuring the fixation of the upper and lower guides of the valve plate when the valve is switched. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The figure is a schematic cross-sectional structure diagram of a high-temperature triple-eccentric butterfly valve with elastic compensation according to an embodiment of the present invention.

[0017] Figure 2 for Figure 1 Enlarged view of point A in .

[0018] Figure 3 for Figure 1 Schematic diagram of the structure of the thrust gasket in the butterfly valve shown.

[0019] Figure 4 for Figure 1 A partial exploded view of the installation structure of the thrust washer and disc spring in the butterfly valve is shown.

[0020] Figure 5 for Figure 1 A partial exploded view of the installation structure of the connecting key in the butterfly valve is shown.

[0021] Explanation of the accompanying drawings: 1. valve body; 2. disc plate; 3. valve stem; 31. second keyway; 4. valve cover; 5. end cover; 51. mounting groove; 52. limit groove; 6. thrust washer; 61. limit block; 62. hardened layer; 7. disc spring; 8. thrust bearing; 81. first keyway; 9. connecting key; 10. shaft spacer; 11. sealing ring; 12. upper bearing; 13. upper dust ring; 14. lower bearing; 15. lower dust ring; 16. packing pressure plate; 17. packing; 18. packing seat; 19. bearing gasket. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0024] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist.

[0025] See also Figures 1 to 5 .

[0026] The high-temperature three-eccentric butterfly valve with elastic compensation of the present invention comprises a valve body 1, a disc plate 2 installed in the valve body 1, a valve stem 3 inserted in the valve body 1 and connected to the disc plate 2, a valve cover 4 fixed on the top of the valve body 1 and an end cover 5 fixed on the bottom of the valve body 1, a thrust washer 6 is provided at the bottom of the valve stem 3, the thrust washer 6 is supported on the end cover 5 and a disc spring 7 is provided between the thrust washer 6 and the end cover 5.

[0027] The present invention provides elastic compensation for the movement of the valve stem by arranging a thrust washer and a disc spring, and by compressing and extending the disc spring under different working conditions. Under high temperature conditions, when the valve stem is heated and extended, the disc spring below the thrust washer will be squeezed, and the compensation space reserved for thermal expansion will not cause the valve stem shaft end to be stuck; under normal temperature conditions, the thrust washer will press the valve stem shaft end under the action of the disc spring, so that the valve stem maintains a stable relative position, thereby ensuring the fixation of the upper and lower guides of the valve plate when the valve is switched.

[0028] In one embodiment, a mounting groove 51 is formed on the top surface of the end cover 5, and the thrust washer 6 is located in the mounting groove 51. With this design, the installation of the thrust washer and the disc spring is limited, and the structure is more stable.

[0029] In one embodiment, a limiting groove 52 is formed on the bottom wall of the installation groove 51, and a limiting block 61 is provided at the bottom of the thrust washer 6, and the limiting block 61 is clamped in the limiting groove 52. In the prior art, the valve stem lacks positioning, and when the valve is switched, the valve stem rotates with the disc plate, and other positioning components also rotate. The present invention makes the above design, and through the positioning cooperation of the limiting block and the limiting groove, the thrust washer will not rotate with the valve stem when the valve stem rotates, thereby ensuring the stability of the disc spring working space and working height.

[0030] In a specific implementation, the limiting groove 52 and the limiting block 61 may be in a rectangular shape, or other non-circular cross-sectional shapes, as long as the rotation of the thrust washer can be limited. In addition, the anti-rotation structure may also be replaced by a pin anti-rotation structure.

[0031] In one embodiment, the top surface of the thrust washer 6 is provided with a hardened layer 62. This design forms a certain hardness difference with the valve stem shaft end, reduces wear and metal adhesion, and ensures service life.

[0032] In one embodiment, the lower end of the valve stem 3 is sleeved with a thrust bearing 8, a first keyway 81 is formed on the inner side of the bottom of the thrust bearing 8, a second keyway 31 is formed at the lower end of the valve stem 3 at a position corresponding to the first keyway 81, and a connecting key 9 is installed in the first keyway 81 and the second keyway 31. In the prior art, there is no fixed fit at the connection between the valve stem and the thrust bearing, the movement direction is not accurate, and the connection is unstable. The present invention can ensure a high-precision and stable connection between the thrust bearing and the valve stem by setting a keyway to fit the connecting key, and at the same time, the thrust bearing can move closely and synchronously with the valve stem, realizing a more accurate thrust function when the valve stem moves upward.

[0033] In a specific implementation, two pairs of connecting keys 9 can be symmetrically arranged on both sides of the valve stem 3 and the thrust bearing 8, and the effect is more reliable. In addition, the top surface of the thrust bearing 8 can be hardened so that the surface can achieve smooth relative movement with the bearing or spacer above, thereby ensuring accurate positioning during operation.

[0034] In one embodiment, the connecting key 9 is in the shape of a flat, oval block.

[0035] In one embodiment, the upper portion of the valve stem 3 is sequentially sleeved with a shaft spacer 10, a sealing ring 11 and an upper bearing 12 from top to bottom. The valve stem 3 is partially hardened corresponding to the upper bearing 12, and an upper dust ring 13 is provided between the lower end of the upper bearing 12 and the valve stem 3.

[0036] In one embodiment, a lower bearing 14 is sleeved on the lower portion of the valve stem 3 , a portion of the valve stem 3 corresponding to the lower bearing 14 is hardened, and a lower dust ring 15 is provided between the upper end of the lower bearing 14 and the valve stem 3 .

[0037] In the prior art, the valve stem is an integrated design. Under high temperature conditions, the normal fit between the valve stem and the bearing will also be affected due to the reduction in the hardness of the metal material and the decline in mechanical properties. If the hardness of the valve stem is too low, it is easy to be squeezed and deformed by the bearing during operation, resulting in an increase in the fit clearance between the bearing and the valve stem, which in turn affects the sealing performance and transmission accuracy.

[0038] The present invention hardens the parts of the valve stem corresponding to the upper and lower bearings to construct a hardness difference between the valve stem and the contact surface of the bearing, thereby reducing wear, forming a good matching relationship, and ensuring the reliability of the seal.

[0039] The hardening design in the present invention is achieved by spraying or surfacing a hardening layer.

[0040] The hardened layer of the present invention can be made of hard alloy such as Stellite, nickel-based alloy, or sprayed tungsten carbide, etc., with a hardness of HRC40 or above, and the present invention does not make any special restrictions.

[0041] In a specific implementation, a bearing gasket 19 is provided between the lower bearing 14 and the thrust bearing 8 .

[0042] In one embodiment, the valve cover 4 is an extended structure, and a packing plate 16, a packing 17 and a packing seat 18 are sequentially sleeved between the valve stem 3 and the valve cover 4 from top to bottom. A circle of steps is opened on the upper inner circumference of the valve cover 4, and the packing plate 16, the packing 17 and the packing seat 18 are located in the steps. In a high-temperature environment, the temperature and pressure of the medium of a shorter valve cover may affect the sealing performance of the valve. The present invention lengthens the valve cover (according to the actual working temperature, the length can be extended by 150~600mm, as long as the high-temperature medium does not affect the packing seal, and the present invention does not make special restrictions). The present invention prevents the high-temperature medium from entering the packing through a multi-channel sealing structure, provides better protection for the packing, reduces the direct impact and erosion of the high-temperature medium on the packing, and thus improves the sealing performance of the valve. In addition, the lengthened valve cover can also increase the length of the connection part between the valve and the pipeline, making the sealing surface tighter and further preventing medium leakage.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-temperature three-eccentric butterfly valve with elastic compensation, comprising a valve body, a disc plate installed in the valve body, a valve stem inserted in the valve body and connected to the disc plate, a valve cover fixed on the top of the valve body, and an end cover fixed on the bottom of the valve body, characterized in that: The bottom of the valve stem is padded with a thrust washer, the thrust washer is supported on the end cover, and a disc spring is arranged between the thrust washer and the end cover.

2. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 1, characterized in that: A mounting groove is formed on the top surface of the end cover, and the thrust washer is located in the mounting groove.

3. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 2, characterized in that: A limiting groove is formed on the bottom wall of the installation groove, and a limiting block is provided at the bottom of the thrust washer, and the limiting block is clamped in the limiting groove.

4. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 1, 2 or 3, characterized in that: The top surface of the thrust washer is provided with a hardened layer.

5. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 1, 2 or 3, characterized in that: The lower end of the valve stem is sleeved with a thrust bearing, the inner side of the bottom of the thrust bearing is provided with a first key groove, the lower end of the valve stem is provided with a second key groove at a position corresponding to the first key groove, and connecting keys are installed in the first key groove and the second key groove.

6. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 5, characterized in that: The connecting key is in the shape of a flat oblong block.

7. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 1, 2 or 3, characterized in that: The upper part of the valve stem is sequentially sleeved with a shaft spacer, a sealing ring and an upper bearing from top to bottom. The portion of the valve stem corresponding to the upper bearing is hardened, and an upper dust ring is provided between the lower end of the upper bearing and the valve stem.

8. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 7, characterized in that: The lower part of the valve stem is sleeved with a lower bearing, the part of the valve stem corresponding to the lower bearing is hardened, and a lower dust ring is arranged between the upper end of the lower bearing and the valve stem.

9. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 8, characterized in that: The hardening design is achieved by spraying or cladding a hardening layer.

10. The high temperature triple eccentric butterfly valve with elastic compensation according to claim 1, 2 or 3, characterized in that: The valve cover is an elongated structure, and a packing pressure plate, a packing and a packing seat are sequentially sleeved between the valve stem and the valve cover from top to bottom. A circle of steps is opened on the upper inner circumference of the valve cover, and the packing pressure plate, the packing and the packing seat are located in the step.

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