DOME VALVE ADJUSTABLE TOP PLATE

Abstract

A valve with a valve upper plate defining an inlet, a valve body defining an outlet, and a fluid passage. A closure member is disposed in the fluid passage between the inlet and the outlet and has a convex sealing surface and is rotatable between a closed position in which the closure member extends across the fluid passage with the convex sealing surface oriented towards the inlet and an open position in which fluid is able to flow through the fluid passage from the inlet to the outlet. A resilient sealing ring, when the closure member is in the closed position, is moveable between a first configuration in which the sealing ring forms a seal around a circumference of the convex sealing surface and a second configuration in which the valve comprises a circumferential gap between the convex sealing surface and the sealing ring.

Claims

1. A valve comprising: a valve upper plate having an inlet; a valve body having an outlet; a fluid passage extending between the inlet and the outlet; a closure member disposed in the fluid passage between the inlet and the outlet; a convex sealing surface, wherein the closure member is rotatable between a closed position in which the closure member extends across the fluid passage with the convex sealing surface oriented towards the inlet and an open position in which fluid is able to flow through the fluid passage from the inlet to the outlet; a resilient sealing ring attached to the valve upper plate and extending around the fluid passage, and, when the closure member is in the closed position, is moveable between a first configuration in which the sealing ring forms a seal around a circumference of the convex sealing surface and a second configuration in which the valve comprises a circumferential gap between the convex sealing surface and the sealing ring; and at least two movable adjustors, wherein the plurality of movable adjustors are capable of adjusting and/or defining the size of the circumferential gap between the convex sealing surface and the sealing ring.

2. The valve according to claim 1, wherein the sealing ring is attached to the valve upper plate via an insert ring.

3. The valve according to claim 1, wherein the at least two movable adjustors are adapted to be adjusted without removing the valve upper plate.

4. The valve according to claim 1, wherein the sealing ring comprises an inflatable portion which in use is pressurized and depressurized to facilitate movement of the sealing ring between the first and second configurations.

5. The valve according to claim 1, wherein the valve upper plate is attached to the valve body with a plurality of upper plate fasteners, and wherein the plurality of movable adjustors are located inside the valve upper plate.

6. The valve according to claim 1, wherein the valve further comprises an intermediate plate located between the valve body and the valve upper plate, and wherein the at least two movable adjusters are located in the intermediate plate.

7. The valve according to claim 7, wherein the valve upper plate is attached to the intermediate plate with the plurality of upper plate fasteners, and the intermediate plate is attached to the valve body with a plurality of valve body fasteners.

8. The valve according to claim 7, wherein the intermediate plate comprises a plurality of seals, wherein at least one seal is located between the intermediate plate and the valve upper plate, and at least one seal is located between the intermediate plate and the valve body.

9. The valve according to claim 1, wherein to adjust or define the circumferential gap size, the at least two movable adjustors are used to displace the valve upper plate relative to the valve body.

10. The valve according to claim 1, wherein the at least two movable adjustors are grub screws.

11. The valve according to claim 1, wherein the at least two movable adjustors are accessible through the valve upper plate.

12. A method of adjusting a circumferential gap between a convex sealing surface and a resilient inflatable sealing ring of a valve, the valve comprising a valve upper plate defining an inlet, a valve body defining an outlet, and a fluid passage extending between the inlet and the outlet, a closure member having a convex sealing surface disposed in the fluid passage, a resilient sealing ring attached to the valve upper plate extending around the fluid passage, and, when the closure member is in the closed position, the resilient sealing ring is moveable between a first configuration in which the sealing ring forms a seal around a circumference of the convex sealing surface and a second configuration in which the valve comprises a circumferential gap between the convex sealing surface and the sealing ring, and a plurality of movable adjustors, wherein the plurality of movable adjustors are capable of adjusting and/or defining the size of the circumferential gap between the convex sealing surface and the sealing ring, the method comprising: measuring the circumferential gap between the convex sealing surface and the sealing ring to obtain a measurement of the circumferential gap; and moving the plurality of adjustors to displace the valve upper plate from the valve body thereby adjusting the size of the circumferential gap.

13. The method according to claim 12, wherein the plurality of adjustors are moved via through-holes arranged in the valve upper plate without removing the valve upper plate.

14. The method according to claim 12, wherein before moving the plurality of adjustors, a plurality of upper plate fasteners are loosened to allow the valve upper plate to be displaced from the valve body.

15. A kit of parts for a valve comprising: a valve upper plate defining an inlet, suitable for housing a resilient sealing ring and suitable for being attached onto a valve body defining an outlet; a closure member disposed in a fluid passage between the inlet and the outlet, the closure member having a convex sealing surface, wherein the valve upper plate has a series of features arranged in a circular pattern to allow fasteners to be inserted into, to allow the valve upper plate to be attached to the valve body, and to allow a plurality of movable adjustors to be inserted into, wherein the plurality of adjustors are movable in the way that the size of a circumferential gap between the convex sealing surface and the sealing ring can be adjusted.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0061] FIG. 1 is a cross-sectional elevation view of a dome valve;

[0062] FIG. 2 is cross-sectional end elevation view of the valve in FIG. 1;

[0063] FIG. 3 is a cross-sectional elevation view of a valve, showing the valve upper plate, valve body, valve closure member, insert ring, sealing ring, valve upper plate fasteners and gasket shims;

[0064] FIG. 4 is a top view of an embodiment according to the present invention, showing a new upper plate design and valve body fasteners according to an embodiment of the present invention;

[0065] FIG. 5 is a cross-sectional view of the embodiment shown in FIG. 4 along the section line A-A, showing a new upper plate design, valve body, valve closure member, insert ring, sealing ring, seals, intermediate plate, and valve body fasteners according to an embodiment of the present invention;

[0066] FIG. 6 is another cross-sectional view of the embodiment shown in FIG. 4 along the section line B-B, showing amongst other items, the new upper plate design and the adjustors.

[0067] FIG. 7 is a cross-sectional view of the embodiment shown in FIGS. 5 and 6, rotated 90 degrees about the vertical axis.

[0068] FIG. 8 is a detailed view of the sealing ring shown in the first configuration (inflated).

[0069] FIG. 9 is a detailed view of the sealing ring shown in the second configuration (deflated).

DETAILED DESCRIPTION

[0070] FIGS. 1, 2 and 3 show cross sections of a dome valve 1, having an inlet 3 and an outlet 5 defined by a body or housing 9, and an upper plate 7. In use, the outlet is typically at a lower pressure than the inlet. The inlet may for example be connected to a pressure vessel, and the outlet to a conveying pipeline.

[0071] Particulate material may be delivered using a flow of carrier gas, for example air, from the inlet 3 to the outlet 5, via a fluid passage indicated generally as 4.

[0072] In the embodiment shown, the body 9 is bolted at its outlet end to a flange 11 at the inlet to a conveying pipeline. Other connections may be used, such as a tri-clover fitting or the like. At its inlet end, the body 9 is similarly coupled to the outlet of a pressure vessel or hopper.

[0073] As seen best in FIG. 1, the valve 1 includes diametrically opposite disposed bearing arrangements 17 and 19 around a drive shaft 21 and a pivot shaft 23 respectively.

[0074] Drive shaft 21 extends outwardly beyond bearing arrangement 17 to an external drive motor 29, by which the closure member 37 is rotated between opened and closed positions, in use.

[0075] The inward ends of drive shaft 21 and pivot shaft 23 are each attached to a respective downwardly depending portion 31, 33 of the closure member 37.

[0076] The closure member 37 includes a domed portion, which defines a convex sealing surface 38, oriented towards the inlet 3, when the closure member 37 is in the closed position as shown in FIG. 1.

[0077] Integral with portions 31 and 33 is a closure member 37, which has the shape of part of a spherical shell. The arrangement is such that the common axis of shafts 21 and 23 passes through the center of the spherical shell of which closure member 37 forms a part. Rotation of drive shaft 21 by means of motor 29, through an angle of approximately 90 degrees in this embodiment, causes closure member 37 to move from its closed position to its open position as shown by the dotted lines in FIG. 2, in which the closure member is moved out of the fluid passage 4 and fluid is able to flow through the fluid passage 4 from the inlet 3 to the outlet 5.

[0078] The valve comprises a longitudinal central axis 57, which runs down the center of the valve from the inlet 4 to the outlet 5. The valve further comprises a transverse axis 56, which is perpendicular and intersects with the longitudinal central axis 57. The closure member rotates about this transverse axis 56. The fluid passage, closure member 37 and sealing ring are circularly symmetric about the central axis 57. Accordingly, the sealing surface 38 is a part spherical surface. In alternative embodiments, as disclosed above, other geometries are used.

[0079] The valve 1 comprises an upper plate 7, which includes an annular surface 43, which is contoured to match the curvature of closure member 37. When the closure member 37 is in its closed position curved surface 43 lies closely adjacent the convex sealing surface 38. An annular recess 45 is formed in surface 43 and located in recess 45 is an inflatable sealing ring 47. The inflatable sealing ring 47 is bonded or otherwise coupled to the walls of recess 45 except at a central portion thereof, where a pressurisable volume, annular space 55 is defined between the sealing ring 47 and the body 9. The inflatable sealing ring 47 is made of a flexible and resilient hard-wearing material, such as an elastomer as disclosed herein. Extending through the inlet portion 12 of valve assembly 1 is a bore 49, which opens at one end into the annular space 55 and is connected at a connector 51 to a compressed air line 53.

[0080] When closure member 37 is in its closed position, the sealing ring 47 is moveable between a first configuration in which the sealing ring 47 forms a seal around a circumference of the convex sealing surface 38; and a second position in which the valve 1 comprises a circumferential seal gap 60 (visible in FIG. 8) between the convex sealing surface and the sealing ring. Such movement can be affected by pressurizing and depressurizing the annular space 55 defined between the sealing ring 47 and the body 7, via the bore 49. When the sealing ring 47 is in its second configuration, the valve can be opened by rotating the closure member 37 to its open position (dotted lines, FIG. 2). The circumferential gap between the sealing ring 47 and sealing surface 38 ensures that the closure member 37 does not slide against the sealing ring 47 during such rotation, which would otherwise contribute to wear on the relatively soft material of the sealing ring.

[0081] The resilient material of the sealing ring 47 is capable of conforming to the sealing surface 38 to form a seal even when small particles are trapped there between. Consequently, dome valves of this general type find use in the field of particulate material processing. It will be appreciated that, provided the air pressure in space 55 is greater than the pressure difference across the closure member 37, then a gas-tight seal will be maintained between the inlet 3 and outlet 5.

[0082] The circumferential seal gap 60 is checked and adjusted during the initial valve assembly and after any maintenance on the valve i.e. replacement of the inflatable seal 47. The seal gap 60 must be big enough to allow opening and closing of the closure member 37 without the possibility of debris catching and eroding the seal, and at the same time be small enough to ensure that when the seal is inflated there is an airtight connection made.

[0083] In FIG. 3, the valve further comprises an insert ring 64, which provides support for the resilient sealing ring 47 and keeps it in place. As described earlier, the gasket shim design is for adjusting the circumferential seal gap. Gasket shims 62 are used to adjust the distance between the valve upper plate 7 and the valve body 9; and since the sealing ring 47 is attached to the insert ring 64 and the valve upper plate 7, the distance between the sealing ring 47 and the sealing surface 38 of the closure member 37 is also adjusted. The method of adjusting the circumferential seal gap 60 is described below:

[0084] With the closure member 37 (dome) in the closed position, and the resilient/inflatable seal 47 in the deflated configuration, feeler gauges are used to measure the circumferential seal gap 60 between the closure member sealing surface 38 and the inflatable seal 47. If the gap is too big the seal gap 60 is reduced by removing gasket shims 62. If the gap is too small the seal gap 60 is increased by adding gasket shims 62. For this, the upper plate fasteners 66 securing the valve upper plate 7 to the valve body 9 have to be unfastened and removed. After this the valve upper plate 7 has to be removed from the assembly 1. Then the inflatable seal 47, intermediate plate 70, and the insert ring 64 have to be lifted out. An appropriate number of gasket shims 62 have to add or to be removed to give the required seal gap 60. Afterward the insert ring 64, inflatable seal 47, intermediate plate 70, and the valve upper plate 7 have to be refitted. Again, the seal gap 60 has to be rechecked using feeler gauges. These steps have to be repeated as necessary until the required seal gap 60 is achieved, and then the upper plate 7 to the body 9 has to be fastened with the upper plate fasteners 66.

[0085] As will be appreciated, this process is time consuming and can be physically demanding if the valve is large and therefore heavy. Furthermore, the inflatable seal 47 may be damaged in the process of removing from the assembly, for example when placing on the ground.

[0086] FIG. 4 shows a top view of an embodiment of the valve 101 of the present invention. Upper plate fasteners 166 and valve body fasteners 168 are arranged circumferally around axis 157.

[0087] FIGS. 5 and 6 show cross sections of embodiments of the valve 101 shown in FIG. 4, where the closure member 137 is in its closed position. Features in common with valve 1 are provided with like reference numerals incremented by 100.

[0088] FIGS. 5 and 6 show a similar valve to the valves described in FIGS. 1-3, however the valve 101 does not comprise gasket shims 62, used to adjust the circumferential gap 160.

[0089] Instead, the valve 101 comprises a plurality of movable adjustors 180, which are used to adjust the size of the circumferential gap, 160 (see FIGS. 7 and 8). Furthermore, the valve 101 comprises an insert ring 164, an intermediate plate 170, a plurality of valve body fasteners 168, and a plurality of seals 172,174.

[0090] The intermediate plate 170 is attached to the valve body 109 via the plurality of valve body fasteners 168 and is attached to the valve upper plate 107 via the plurality of upper plate fasteners 166. Both sets of fasteners 166, 168 may be arranged in circular patterns which are offset relative to each other around the longitudinal central axis 157 of the valve 101. The offset ensures access to the valve body fasteners 168 through the valve upper plate 107, enabling the intermediate plate 170 to be detached from the valve body 109 without removing the upper plate 107. There may be a plurality such as 4 to 24 upper plate fasteners 166 and a plurality of such as 4 to 24 valve body fasteners 168. The fasteners may, for example, be about M12 to M36 screws.

[0091] The intermediate plate 170 houses the plurality of movable adjustors 180. There may be a plurality such as 4 to 12 movable adjustors 180, which are also arranged in a circular pattern about the longitudinal central axis 157 of the valve 101. The movable adjustors 180 are accessible through the valve upper plate 107, therefore the valve 101 does not need to be disassembled to adjust the circumferential seal gap 160. The adjustors 180 may be screws, ranging in size from about M8 to M27. With the valve body fasteners 168 loose, the movable adjustors 180 as shown in FIG. 6, are screwed in or out of the intermediate plate 170 thereby protruding onto the valve body 109 by varying distances, thus controlling the distance between the valve body 109 and the intermediate plate 170.

[0092] FIGS. 5 and 6 also show the plurality of seals 172, 174, which are usually O-rings. A seal 172 is provided between the intermediate plate 170 and the valve body 109, and a seal 174 is provided between the intermediate plate 170 and the upper plate 107. These seals may be in different locations from the locations shown in the figures, and there also may be more than one seal between each component of the valve 101.

[0093] This arrangement allows the seal gap 160 to be set, for example, as follows: With the closure member (dome) 137 in the closed position, and the resilient/inflatable seal 147 in its second/deflated configuration, feeler gauges are used to measure the circumferential seal gap 160 between the closure member sealing surface 138 and the inflatable seal 147. If the gap is too big the seal gap 160 is reduced by turning the adjusting fasteners 180 anti-clockwise. If the gap is too small the seal gap 160 is increased by turning the adjusting fasteners 180 clockwise. The valve body fasteners 168 securing the intermediate plate 170 to the valve body 109 are loosened.

[0094] A tool is then used to turn the adjustors 180 to give the required seal gap 160. The gap 160 is then checked with feeler gauges.

[0095] With the seal gap 160 set, the valve body fasteners 168 securing the intermediate plate 170 to the valve body 109 are re-tightened.

[0096] The feeler gauges can be inserted at various locations around the circumference of the resilient seal 147, to ascertain the size of the gap. The valve body fasteners 168 in step 2 may be removed from the assembly if loosening is not sufficient to adjust the movable adjustors 180. The plurality of movable adjustors 180 must be adjusted in a similar way, to ensure the intermediate plate 170 and the valve body 109 stay aligned to each other along the longitudinal central axis 157. Ideally, the intermediate plate 170 and the connected components should be displaced at a right angle along the central axis 157 from the valve body 109 to ensure a consistent circumferential gap 160 between the convex sealing surface 138 and the sealing ring 147.

[0097] As can be appreciated, the method above is beneficial to the user as all of the fasteners 166, 168 and movable adjustors 180 can be accessed through the upper plate 107, and the upper plate 107 does not need to be removed to adjust the circumferential seal gap 160. The new design allows the seal gap 160 to be set in less time when compared to valves in the prior art. When maintenance on large valves 101 is carried out, components such as the upper plate, 107 can be heavy and cumbersome to remove. The new design therefore also requires less physical effort to set the seal gap 160, since the upper plate 107 does not need to be removed.

[0098] A further benefit of the new design is manifested during valve maintenance, as the resilient sealing ring 147 can be accessed by removing the valve upper plate 107 only. When the valve upper plate 107 is removed both the sealing ring 147 and the retaining ring 164 can be lifted clear of the intermediate plate 170. No fixings are used to hold the sealing ring 147 and retaining ring 164 to the intermediate plate 170. The sealing ring 147 wraps around the retaining ring 164 as the sealing ring 147 is produced from a flexible rubber compound.

[0099] This is beneficial as it allows the intermediate plate 170 to stay in the same position, therefore keeping the ‘factory set’ circumferential seal gap 160.

[0100] The new adjustable design may be retrofitted to existing valves, allowing existing users to benefit also.

[0101] In FIGS. 5 and 6, the valve comprises a valve upper plate 107, an intermediate plate 170, and a body 109, however the invention disclosed could also work if there was no intermediate plate 170, and the resilient sealing ring 147 was attached directly or indirectly to the upper plate 107. This configuration would result in only one set of fasteners to assemble the valve, attaching the valve upper plate 107 to the valve body 109.

[0102] FIG. 7 is a cross-sectional view of the embodiment shown in FIGS. 5 and 6, rotated 90 degrees about the vertical axis. The transverse axis 156 is orientated into the page and the closure member 137 rotates about this axis, moving between the open and closed positions.

[0103] FIG. 8 shows is a detailed view of the sealing ring 147 shown in the first configuration (inflated), with the seal gap 160 exaggerated for clarity.

[0104] FIG. 9 is a detailed view of the sealing ring 147 shown in the second configuration (deflated), with the seal gap 160 exaggerated for clarity.

[0105] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.