阅读说明：本技术 圆顶阀可调节顶板 (Adjustable top plate of dome valve ) 是由 迈克尔·牛顿 于 2020-04-09 设计创作，主要内容包括：一种阀,其设置有限定入口的阀上板、限定出口的阀体以及在入口和出口之间延伸的流体通道,其中,封闭构件布置在入口和出口之间的流体通道中,封闭构件具有凸形密封面并且可在关闭位置和打开位置之间旋转,在关闭位置中,封闭构件在凸形密封面朝向入口定向的情况下延伸跨过流体通道,在打开位置中,流体能够穿过流体通道从入口流到出口；弹性密封环被安装到阀上板并围绕流体通道延伸,并且当封闭构件处于关闭位置时,弹性密封环可在第一构造和第二构造之间移动,在第一构造中,密封环围绕凸形密封面的圆周形成密封,在第二构造中,阀包括凸形密封面和密封环之间的周向间隙；此外,阀设置有多个可移动调节器,其中多个可移动调节器能够调节和/或限定凸形密封面与密封环之间的周向间隙的尺寸。(A valve provided with an upper valve plate defining an inlet, a valve body defining an outlet, and a fluid passage extending between the inlet and the outlet, wherein a closure member is arranged in the fluid passage between the inlet and the outlet, the closure member having a convex sealing surface and being 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 can flow through the fluid passage from the inlet to the outlet; an elastomeric sealing ring mounted to the valve upper plate and extending around the fluid passage and movable between a first configuration in which the sealing ring forms a seal around the circumference of the male sealing surface and a second configuration in which the valve includes a circumferential gap between the male sealing surface and the sealing ring when the closure member is in the closed position; furthermore, the valve is provided with a plurality of movable regulators, wherein the plurality of movable regulators are capable of adjusting and/or defining the size of the circumferential gap between the male sealing surface and the sealing ring.)

1. A valve (101), comprising:

-a valve upper plate (107) defining an inlet (103),

-a valve body (109) defining an outlet (105), and

a fluid channel extending between the inlet (103) and the outlet (105),

the valve (101) further comprises:

-a closure member (137) arranged in the fluid passage between the inlet (103) and the outlet (105),

-having a convex sealing surface (138), wherein the closure member (137) is rotatable between a closed position, in which the closure member (137) extends across the fluid passage with the convex sealing surface (138) oriented towards the inlet (103), and an open position, in which fluid can flow through the fluid passage from the inlet (103) to the outlet (105),

-an elastic sealing ring (147) mounted to the valve upper plate (107) and extending around the fluid passage and movable between a first configuration in which the sealing ring (147) forms a seal around the circumference of the male sealing surface (138) and a second configuration in which the valve comprises a circumferential gap (160) between the male sealing surface (138) and the sealing ring (147) when the closure member (137) is in the closed position, and

-a plurality of movable adjusters (180), wherein the plurality of movable adjusters (180) are capable of adjusting and/or defining a size of a circumferential gap (160) between the male sealing surface (138) and the sealing ring (147).

2. The valve (101) of claim 1, wherein the sealing ring (147) is mounted to the valve upper plate (107) via an insert ring (164).

3. The valve (101) of any one of the preceding claims, wherein the plurality of movable regulators (180) are adjustable without removing the valve upper plate (107).

4. The valve (101) according to any one of the preceding claims, wherein the sealing ring (147) comprises an expandable portion which is pressurised and depressurised in use to facilitate movement of the sealing ring (147) between the first configuration and the second configuration.

5. The valve (101) of any of the preceding claims, wherein the valve upper plate (107) is mounted to the valve body (109) with a plurality of upper plate fasteners (166) and the plurality of movable regulators (180) are located within the valve upper plate (107).

6. The valve (101) of any of claims 2 to 6, wherein the valve (101) further comprises an intermediate plate (170) located between the valve body (109) and the valve upper plate (107), wherein the plurality of movable regulators (180) are located in the intermediate plate (170).

7. The valve (101) of claim 7, wherein the valve upper plate (107) is mounted to the intermediate plate (170) with the plurality of upper plate fasteners (166) and the intermediate plate (170) is mounted to the valve body (109) with a plurality of valve body fasteners (168).

8. The valve (101) of any of claims 7 to 8, wherein the intermediate plate (170) comprises a plurality of seals, wherein at least one seal (174) is located between the intermediate plate (170) and the valve upper plate (107) and at least one seal (172) is located between the intermediate plate (170) and the valve body (109).

9. The valve according to any of the preceding claims, wherein for adjusting or defining the circumferential gap size, the valve upper plate (107) is displaced relative to the valve body (109) using the plurality of movable adjusters (180).

10. A valve according to any of the preceding claims, wherein the plurality of regulators (180) are grub screws.

11. The valve according to any of the preceding claims, wherein the plurality of regulators (180) are accessible through the valve upper plate (107).

12. A method of adjusting a circumferential gap (160) between a convex sealing surface (138) of a valve (101) and an elastically expandable sealing ring (147),

-the valve (101) comprises an upper valve plate (107) defining an inlet, a valve body (109) defining an outlet, and a fluid passage extending between the inlet and the outlet, a closure member (139) having a convex sealing surface (138) arranged in the fluid passage,

-an elastic sealing ring (147) mounted to the valve upper plate (107) extending around the fluid passage and movable between a first configuration in which the sealing ring (147) forms a seal around the circumference of the male sealing surface (138) and a second configuration in which the valve (101) comprises a circumferential gap (160) between the male sealing surface (138) and the sealing ring (147) when the closure member (137) is in the closed position, and

-a plurality of movable adjusters (180), wherein the plurality of movable adjusters (180) are capable of adjusting and/or defining the size of the circumferential gap (160) between the male sealing surface (138) and the sealing ring (147) using the steps of:

-measuring the circumferential gap (160) between the male sealing face (138) and the sealing ring (147) to obtain a measurement of the circumferential gap (160);

-moving the plurality of adjusters (180) to displace the valve upper plate (107) from the valve body (109) to adjust the size of the circumferential gap (160).

13. The method of claim 12, wherein the plurality of regulators are moved via through holes configured in the valve upper plate (107) without removing the valve upper plate (107).

14. The method of claim 12 or 13, wherein prior to moving the plurality of regulators (180), a plurality of upper plate fasteners (168) are loosened to allow the valve upper plate (107) to be displaced from the valve body (109).

15. A kit of parts for a valve (101), comprising:

-an upper valve plate (107) defining an inlet,

is adapted to receive an elastic sealing ring (147), an

-a valve body (109) adapted to be mounted to define an outlet,

-the valve (101) comprises a closure member (137) arranged in a fluid passage between the inlet and the outlet,

-the closure member (137) has a convex sealing surface (138),

wherein

-said valve upper plate (107) having

-a series of features arranged in a circular pattern

To allow the insertion of fasteners (166, 168),

-to allow mounting of said valve upper plate (107) to said valve body (109), and

-to allow insertion of a plurality of movable adjusters (180);

wherein the plurality of adjusters are movable in a manner that enables adjustment of a size of a circumferential gap between the male sealing face and the seal ring.

Technical Field

The present invention relates to a valve, in particular a valve for pneumatic conveying of particulate material.

Background

Pneumatic conveying by pressure or vacuum is a technique for transporting particulate material along a pipeline. These techniques are typically used to transport materials over distances typically in the range of 10m to 500m, and in some cases even further. Pneumatic transport avoids the need to use conveyor belts and the like, which can be bulky and costly to maintain.

Pneumatic transport techniques are particularly useful where the material must be transported along a complex path or must be transported to multiple delivery points. These techniques also ensure that the particulate material is contained entirely within the duct, which can avoid the need to handle dust or contamination from the material along the path of the conveying duct.

Other stages of pneumatic conveying and material handling may be performed at elevated pressures, or pressure differentials between different parts of a conveying or material handling facility may be used. For example, dense phase positive pressure or vacuum pneumatic conveyance is often used to transport dense phase particles that are not suitable for conveyance by suspension in a gas stream, such as materials that are prone to particle breakage, or particularly abrasive or brittle materials.

Conventional pressurized dense phase pneumatic conveying systems include a hopper from which particulate material is delivered into a pressure vessel. The pressure vessel is typically pressurized with compressed air and the particulate material is delivered under pressure into a conveying pipeline. The pressurized air in the pressure vessel expands into the transport conduit and propels the particulate material along the conduit to a delivery point at a lower (e.g., atmospheric) pressure.

The inlet valve between the pressure vessel and the conveying pipe, or indeed any valve that delivers a flow comprising particulate material across a pressure differential, must be able to open and close in the presence of particulates, and must have a suitable working life.

GB1539079 (macherber Engineering) describes an inlet valve for use with a container containing pressurised powder. The valve described in GB1539079 is commonly referred to as a "dome valve" and is now commonly used in particulate material processing such as dense phase transport and process injection techniques. A conventional dome valve is shown in fig. 1 and 2 and described in further detail below.

The dome valve includes a closure member having a convex sealing surface that generally defines a portion of a spherical surface. When the valve is closed, the closure member blocks a passage extending through the valve.

A key aspect of the valve is its elastomeric/expandable seal design to avoid wear. The sealing member provides a non-contacting gap when the valve is moved between the open and closed positions and provides a gas-tight seal when the valve is closed, even in the presence of powder contamination. The size of the non-contact gap to be set is determined by the material of the valve. The particle size of the material can vary between 1 μm and 200mm in diameter.

The non-contact spacing or seal gap between the convex sealing surface of the dome and the inflatable seal is adjusted in prior art designs by using a gasket between the valve body and the valve upper plate (note that the non-contact spacing is set when the inflatable seal is deflated). Adding the gasket shims raises the top plate relative to the valve body, which increases the size of the circumferential seal gap, and reducing the number of gasket shims reduces the size of the circumferential seal gap. The gasket design can be seen in fig. 3.

The process of setting the seal clearance in the prior art is as follows:

with the closure member (dome) in the closed position and the elastomeric/inflatable seal in the collapsed configuration, a feeler gauge is used to measure the sealing gap between the dome and the inflatable seal. If the gap is too large, the seal gap is reduced by removing the gasket. If the gap is too small, the seal gap is increased by adding a gasket.

Therefore, the fastener for fixing the upper plate of the valve must be loosened and removed. The valve upper plate must then be removed from the assembly. The inflatable seal, intermediate plate and insert ring must then be removed.

In this position, an appropriate number of gasket washers can be added or removed to provide the desired sealing gap. Thereafter, the insert ring, intermediate plate, inflatable seal and upper valve plate must be reassembled, and the seal gap must be rechecked using a feeler.

All the mentioned steps must be repeated as often as necessary until the desired sealing gap is reached. The upper plate can then be secured to the body with the upper plate fasteners.

Setting the seal gap in this manner is a time consuming process and also physically demanding for larger valves. Furthermore, after valve maintenance, the seal clearance may be set incorrectly due to inexperience of customer maintenance engineers. Improper setting of the seal gap may result in premature failure of the replacement inflatable sealing ring.

For the reasons stated above, there remains a need to solve or mitigate at least one or more of the problems described above.

It is an object of the present invention to provide an improved valve for pneumatic conveyance of particulate material.

Disclosure of Invention

According to a first aspect of the present invention, there is provided a valve comprising an upper valve plate defining an inlet, a valve body defining an outlet, and a fluid passage extending between the inlet and the outlet. The valve further comprises: a closure member disposed in the fluid passage between the inlet and the outlet, having 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 toward the inlet, and an open position in which fluid can flow through the fluid passage from the inlet to the outlet; a resilient sealing ring extending around the fluid passage between an inlet and an outlet and mounted to the valve upper plate and movable between a first configuration in which the sealing ring forms a seal around the circumference of the male sealing face and a second configuration in which the valve includes a circumferential gap between the male sealing face and the sealing ring when the closure member is in the closed position; and a plurality of adjusters capable of adjusting a size of a circumferential gap between the male sealing surface and the seal ring.

The sealing ring may be mounted to the valve upper plate via an insert ring. The insert ring may be located between the valve upper plate and the sealing ring, and may be mounted to the valve upper plate, the valve intermediate plate, or both.

The insert ring may serve to hold the sealing ring in place and it may provide a chamber for compressed gas to expand into, thereby inflating the seal. The insert ring may hold the seal concentrically in the upper plate.

The circumferential gap size may be adjusted by displacing the valve upper plate relative to the valve body. The plurality of movable adjusters may be adjusted to protrude to different degrees onto the valve body, thereby increasing or decreasing the distance between the upper plate and the main body.

The valve body may include a plurality of seats or plates to receive the movable adjuster to prevent wear of the valve body. The movable adjuster may be a grub screw having, for example, a hex head (which may be adjusted by a wrench such as a hex wrench). Alternatively, the movable adjuster may be a screw having a slotted head, a crosshead, a quincunx, or the like.

The plurality of movable adjusters can be adjusted without removing the upper plate. This allows the movable regulator to be adjusted without disassembling the valve.

The sealing ring may be substantially annular or ring-shaped about a substantially longitudinal or longitudinal central axis of the valve. The scan profile of the seal ring may be constant about a generally longitudinal or longitudinal central axis. The longitudinal central axis is shown in fig. 5 and 6(157) and passes through the line: this line would be formed if it intersected the center point of the respective circular geometries of the upper plate, seal ring and valve body.

The fluid passage may be substantially symmetrical or symmetrical around the central axis, at least in the region of the sealing ring. The sealing ring may be substantially circularly symmetric or may be described as elliptically symmetric. In some embodiments, other symmetries such as square or rectangular symmetries (e.g., where the seal ring is saddle-shaped) are also possible when viewed along the axis.

The valve body may be substantially symmetrical or symmetrical around the centre axis, at least in the parts defining the fluid passage in the area of the sealing ring and the fluid guiding surface.

The fluid passage may extend along a central axis.

The closure member may be rotatable about an axis that is substantially perpendicular or perpendicular to the central axis. Typically, the closure member is rotatable about a transverse axis substantially perpendicular to the longitudinal central axis of the valve. The rotation of the closure member may be achieved electromechanically, mechanically, or may be actuated by a fluid (e.g., hydraulically or pneumatically). The valve may be a solenoid valve. The valve may be a pneumatic valve or a hydraulic valve.

The sealing ring may comprise an elastomeric material such as an elastomer. Elasticity refers to the ability of a material to deform and recover its original shape. Any suitable elastomeric material may be used for the sealing ring, such as a fluoropolymer (e.g., viton or teflon), polyurethane, neoprene or organo-fat material, nitrile, or polypropylene (e.g., EPDM), among others.

The closure member is rotatable about a transverse axis substantially perpendicular or perpendicular to a substantially longitudinal or longitudinal central axis of the valve. The transverse axis is shown at 156 in fig. 5 and 6.

The rotation of the closure member may be achieved electromechanically, mechanically, or may be actuated by a fluid (e.g., hydraulically or pneumatically). The valve may be a solenoid valve. The valve may be a pneumatic valve or a hydraulic valve.

The convex sealing surface may be generally oriented toward the inlet when the closure member is in the closed position. When the closure member is in the open position, the closure member may be rotated up to 90 degrees or more, thereby moving the convex sealing surface out of the fluid passage or as far to its side as possible in order to maximize the flow area through the valve.

The convex sealing surface may be a part-spherical surface (e.g., where the fluid passage in its region is circularly symmetric) or may be a part-ovoid surface or a part-cylindrical surface in alternative embodiments.

The sealing ring may comprise an expandable portion. For example, a pressurizable volume may be defined between the seal ring and the body. The expandable member or pressurized volume may be pressurized and depressurized to facilitate movement of the sealing ring between the first configuration and the second configuration.

The valve upper plate may be mounted to the valve body with a plurality of upper plate fasteners, and wherein the plurality of movable regulators may be located inside the valve upper plate. The upper plate fastener may be a hex head screw adjustable with a hex wrench. Alternatively, the fasteners may be screws having a socket head, crosshead, quincunx, or the like. The movable adjuster may be adjusted from within the valve upper plate to project onto the valve body to vary the distance between the valve upper plate and the valve body to adjust and/or define the distance between the resilient sealing ring and the convex sealing surface.

The valve may further include an intermediate plate located between the valve body and the valve upper plate, wherein the intermediate plate enables removal of the upper plate without removing the sealing ring and the insert ring. This facilitates inspection of the seal ring, since the seal gap is not disturbed as it would be if there were no intermediate plate.

The valve upper plate may be mounted to the intermediate plate with a plurality of upper plate fasteners and the intermediate plate may be mounted to the valve body with a plurality of valve body fasteners. Similar to the upper plate fastener, the valve body fastener may be a hex head screw that is adjustable with a hex wrench. Alternatively, the fasteners may be screws having a socket head, crosshead, quincunx, or the like. The upper plate fasteners and the valve body fasteners are both accessible through the valve upper plate, allowing the intermediate plate to be removed with the valve upper plate still mounted to the intermediate plate.

The plurality of valve body fasteners may be oriented about the longitudinal axis in a generally circular pattern. The generally circular pattern may be oriented away from the pattern of upper plate fasteners to allow access to the valve body fasteners through the valve upper plate.

The valve upper plate, the intermediate plate and the valve body may each have a centrally located symmetrical bore that is generally circular about the longitudinal central axis of the valve. A series of holes describe fluid passages that may extend from an inlet to an outlet of the valve.

The intermediate plate may include a plurality of seals, wherein at least one seal may be located between the intermediate plate and the valve upper plate, and at least one seal may be located between the intermediate plate and the valve body. The plurality of seals may be "O-rings". Alternatively, they may have other cross-sections, including X-shaped, square, etc. The seal may prevent fluid and gas from escaping from the fluid passageway of the valve. The seals may be housed in seats between the components they seal. The seal may be made of any synthetic rubber or thermoplastic.

The circumferential clearance dimension may be described as the shortest linear distance between the convex sealing surface and the sealing ring. In most cases, the straight-line distance is perpendicular to the convex sealing surface. If the convex sealing surface is spherical in the shape of a dome and the line defining the size of the gap extends into the dome, it will pass through the centre of curvature of the dome. Ideally, the gap size around the circumference of the seal ring would remain consistent, giving only one linear gap size. To this end, the various parts of the assembly must be adjusted to have equal distances along the longitudinal axis of the valve by using an adjuster. If the movable adjuster is adjusted in a different manner, the size of the gap at different positions around the circumference of the sealing ring may vary. The shortest linear distance may be oriented substantially perpendicular to the convex sealing surface and the sealing ring.

The circumferential gap size may be from 0 (direct contact) to 1.5 mm. The plurality of movable adjusters may be oriented generally about the longitudinal axis in a circular pattern. The movable adjuster may be a circular pattern similar to the fasteners described above while maintaining a suitable offset to enable access to the movable adjuster through the valve upper plate. If the middle plate is included in the assembly, the upper plate fasteners, the valve body fasteners, and the movable regulator are all accessible from the valve upper plate. This allows access to the fasteners and the regulator without removing the upper valve plate.

To adjust the circumferential gap size, a plurality of movable adjusters may be used to move the valve upper plate relative to the valve body. This may be done in a manner similar to when displacing the intermediate plate relative to the valve body. As previously mentioned, the components may preferably be displaced perpendicularly to each other, ideally along the longitudinal centre axis.

The plurality of upper panel fasteners may be oriented about the longitudinal axis in a generally circular pattern.

The closure member may be dome shaped. The plurality of movable regulators may be accessible through the valve top plate.

In another aspect, the invention extends to a method of adjusting a circumferential clearance between a male sealing surface of a valve and an elastomeric seal ring, the method comprising: providing a valve having an upper valve 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 between the inlet and the outlet; providing an elastomeric sealing ring extending around the fluid passage between the inlet and the outlet; providing a plurality of regulators; the closure member is in a closed position and the sealing ring is in a retracted position, thereby forming a circumferential gap between the male sealing face and the sealing ring; measuring the circumferential clearance between the male sealing face and the seal ring to obtain a measurement of the circumferential clearance; adjusting the plurality of adjusters to displace the valve upper plate from the valve body to adjust the size of the circumferential gap.

The method may include allowing adjustment of the plurality of movable adjusters without removing the valve upper plate.

In this method, the sealing ring may be annular about a longitudinal central axis of the valve.

In the method, prior to adjusting the plurality of movable adjusters, the plurality of upper plate fasteners may be loosened to allow the valve upper plate to be displaced from the valve body.

In the method, the valve may further include an intermediate plate between the valve body and the valve upper plate, which may allow the valve upper plate to be removed without removing the sealing ring from the valve body.

In another aspect, the invention extends to a kit of parts for a valve, comprising: an upper valve plate defining an inlet adapted to receive an elastomeric sealing ring and adapted to be mounted to a valve body; wherein the valve upper plate has a series of features arranged in a circular pattern to allow insertion of fasteners to allow mounting of the valve upper plate to the valve body, and a series of features arranged in a circular pattern to allow insertion of a plurality of movable adjusters; wherein the valve comprises a valve body defining an outlet, a closure member arranged in a fluid passage between the inlet and the outlet, the closure member having a male sealing face, wherein the plurality of movable adjusters are capable of adjusting the size of a circumferential gap between the male sealing face and the sealing ring.

In another aspect, the invention extends to a pressure vessel having an outlet coupled to the inlet of the valve of the first aspect. The valves may be coupled directly, or via a length of conduit or tubing.

The pressure vessel may form part of a pneumatic system for the particulate material. The particulate material pneumatic system may be, for example, a particulate material transport system, such as a dense phase transport system, for transporting dense phase particulate material, such as sodium sulfate, sodium carbonate, sand, gypsum, alumina, metallurgical coke, clinker, metal dust and concentrate, or other inorganic salts, and catalyst supports, among others. Particulate material pneumatic systems may be used to transport fuels such as coal, biomass or waste. The pressure vessel may for example be a conveyor for a particulate material conveying apparatus.

The particulate material pneumatic system may be a batch feed system in which particulate material such as the above-mentioned materials are dispensed from a holding container in batches of predetermined size. The particulate material system may be an open phase transport system (also known as "dilute phase" transport, where the ratio of transport product to transport gas (and typically also transport gas pressure) is lower than dense phase or medium phase pneumatic transport).

The particulate material pneumatic system may be a gravity feeder in which the batch size is determined by monitoring weight changes in a part of the apparatus. Typically, a gravity feeder comprises a holding container and the batch size is determined by monitoring the weight change of the holding container (and any auxiliary equipment that cannot be implemented independently of the holding container, e.g. by a flexible conduit).

Further optional features relating to various aspects of the invention correspond to further optional features of various other aspects of the invention.

Drawings

Non-limiting exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

figure 1 is a cross-sectional elevation view of a dome valve according to the prior art.

Fig. 2 is a cross-sectional end elevation view of the valve of fig. 1 according to the prior art.

FIG. 3 is a cross-sectional elevation view of a valve showing a valve upper plate, a valve body, a valve closure member, an insert ring, a sealing ring, a valve upper plate fastener and a gasket according to the prior art.

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.

FIG. 5 is a cross-sectional view of the embodiment of FIG. 4 along section line A-A, illustrating the new upper plate design, valve body, valve closure member, insert ring, seal, intermediate plate, and valve body fastener according to an embodiment of the present invention.

FIG. 6 is another cross-sectional view of the embodiment shown in FIG. 4 along section line B-B, showing the new upper plate design and the regulator.

Fig. 7 is a cross-sectional view of the embodiment of fig. 5 and 6 rotated 90 degrees about a vertical axis.

Figure 8 is a detailed view of the seal ring shown in a first configuration (expanded).

Figure 9 is a detailed view of the seal ring shown in a second configuration (collapsed).

Detailed Description

Figures 1, 2 and 3 show a cross-section of a prior art dome valve 1, the prior art 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 may be connected to a delivery conduit.

A flow of carrier gas, for example air, may be used to deliver the particulate material from the inlet 3 to the outlet 5 via a fluid channel generally indicated at 4.

In the embodiment shown, the body 9 is bolted at its outlet end to a flange 11 at the inlet of a conveying pipe (not shown). Other connections such as a clover assembly or the like may be used. At its inlet end, the body 9 is similarly coupled to the outlet of a pressure vessel or hopper.

As best shown in fig. 1, the valve 1 comprises bearing means 17 and 19 arranged diametrically opposite around the drive shaft 21 and the pivot shaft 23, respectively.

The drive shaft 21 extends outwardly beyond the bearing arrangement 17 to the external drive motor 29, and in use the closure member 37 is rotated between the open and closed positions by the external drive motor 29.

The inner ends of the drive shaft 21 and the pivot shaft 23 are each mounted to a respective downwardly depending portion 31, 33 of the closure member 37.

The closure member 37 comprises 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 shown in figure 1.

Integral with the portions 31 and 33 is a closure member 37 having the shape of a portion of a spherical shell. This arrangement is such that the common axis of the shafts 21 and 23 passes through the centre of the spherical shell of which the closure member 37 forms part. In the present embodiment, rotation of the drive shaft 21 by means of the motor 29 through an angle of approximately 90 degrees causes the closure member 37 to move from its closed position to its open position as shown in chain line in fig. 2, in which the closure member is moved out of the fluid passage 4 and fluid can flow through the fluid passage 4 from the inlet 3 to the outlet 5.

The valve comprises a longitudinal centre axis 57 extending from the inlet 4 down the centre of the valve to the outlet 5. The valve also includes a transverse axis 56 perpendicular to and intersecting the longitudinal central axis 57. The closure member rotates about this transverse axis 56. The fluid passage, the closure member 37 and the sealing ring are circularly symmetric about the central axis 57. Thus, the sealing surface 38 is a part spherical surface. In alternative embodiments, other geometries are used, as described above.

The valve 1 comprises an upper plate 7 comprising an annular face 43 contoured to match the curvature of the closure member 37. The curved surface 43 abuts the convex sealing surface 38 when the closure member 37 is in its closed position. An annular recess 45 is formed in face 43, and located in recess 45 is an inflatable sealing ring 47. The inflatable sealing ring 47 is bonded or otherwise coupled to the wall of the recess 45 except at its central portion where the sealing ring 47 and the main body 9 define a pressurizable volume, annular space 55 therebetween. The inflatable sealing ring 47 is made of a flexible and resilient wear resistant material, such as the elastomers disclosed herein. A bore 49 extends through the inlet portion 12 of the valve assembly 1, the bore 49 opening at one end into the annular space 55 and connecting to a compressed air line 53 at a connector 51.

When the closure member 37 is in its closed position, the sealing ring 47 is movable between a first configuration in which the sealing ring 47 forms a seal around the circumference of the male sealing face 38, and a second position in which the valve 1 includes a circumferential sealing gap 60 (visible in fig. 8) between the male sealing face and the sealing ring. This movement can be performed by pressurising and depressurising an annular space 55 defined between the sealing ring 47 and the main body 7 via the aperture 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 (dash-dot-dash line, fig. 2). The circumferential clearance between the sealing ring 47 and the sealing surface 38 ensures that the closure member 37 does not slip against the sealing ring 47 during such rotation, which would otherwise contribute to wear of the relatively soft material of the sealing ring.

The resilient material of the sealing ring 47 is able to conform to the sealing surface 38 to form a seal even when small particles are trapped therebetween. Accordingly, dome valves of this general type are useful in the field of particulate material processing. It will be appreciated that if the air pressure in the space 55 is greater than the pressure differential across the closure member 37, an airtight seal will be maintained between the inlet 3 and the outlet 5.

The circumferential seal gap 60 is inspected and adjusted during initial valve assembly and after any maintenance on the valve (i.e., replacement of the expandable seal 47). The seal gap 60 must be large enough to allow opening and closing of the closure member 37 without debris catching and eroding the seal, and at the same time small enough to ensure that an air tight connection is formed when the seal expands.

In fig. 3, the valve further includes an insert ring 64 which provides support for and holds the resilient sealing ring 47 in place. As previously mentioned, the gasket shim is designed to adjust the circumferential seal gap. The gasket washer 62 is used for adjusting the distance between the valve upper plate 7 and the valve body 9; and since the seal ring 47 is fitted to the insert ring 64 and the valve upper plate 7, the distance between the seal 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 as follows:

with the closure member 37 (dome) in the closed position and the resilient/expandable seal 47 in the collapsed configuration, a feeler gauge is used to measure the circumferential seal gap 60 between the closure member sealing surface 38 and the expandable seal 47. If the gap is too large, the seal gap 60 is reduced by removing the gasket 62. If the gap is too small, the seal gap 60 is increased by adding a gasket washer 62. To do so, the upper plate fasteners 66 securing the valve upper plate 7 to the valve body 9 must be loosened and removed. Thereafter, the valve upper plate 7 must be removed from the assembly 1. The inflatable seal 47, intermediate plate 70 and insert ring 64 must then be removed. An appropriate number of gasket washers 62 must be added or removed to provide the desired seal gap 60. The insert ring 64, inflatable seal 47, intermediate plate 70 and upper valve plate 7 must then be reassembled. Again, the seal gap 60 must be rechecked using a feeler. These steps must be repeated as necessary until the desired seal gap 60 is achieved, and then the upper plate 7 must be secured to the body 9 with the upper plate fasteners 66.

It will be appreciated that if the valve is large and therefore heavy, the process is time consuming and requires physical effort. Furthermore, the inflatable seal 47 may be damaged during removal from the assembly, for example when placed on the ground.

Fig. 4 shows a top view of an embodiment of the valve 101 of the present invention. An upper plate fastener 166 and a valve body fastener 168 are circumferentially disposed about the axis 157.

Fig. 5 and 6 show a cross-section of the embodiment of the valve 101 shown in fig. 4 with the closure member 137 in its closed position. Similar reference numerals increased by 100 are provided for features common with the valve 1.

Fig. 5 and 6 show a valve similar to the valve described in fig. 1 to 3, but the valve 101 does not comprise a gasket washer 62 for adjusting the circumferential gap 160.

Instead, the valve 101 includes a plurality of movable adjusters 180 for adjusting the size of the circumferential gap 160 (see fig. 7 and 8). In addition, valve 101 includes insert ring 164, intermediate plate 170, a plurality of valve body fasteners 168, and a plurality of seals 172, 174.

The intermediate plate 170 is mounted to the valve body 109 via a plurality of valve body fasteners 168 and to the valve upper plate 107 via a plurality of upper plate fasteners 166. The two sets of fasteners 166, 168 may be arranged in a circular pattern that is offset relative to each other about 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 such that the intermediate plate 170 can be detached from the valve body 109 without removing the upper plate 107. There may be a plurality (such as 4 to 24) of upper plate fasteners 166 and a plurality (such as 4 to 24) of valve body fasteners 168. The fasteners may be, for example, approximately M12 to M36 screws.

The intermediate plate 170 houses a plurality of movable adjusters 180. There may be a plurality (such as 4 to 12) of movable adjusters 180 also arranged in a circular pattern about the longitudinal center axis 157 of the valve 101. The movable adjuster 180 is accessible through the valve upper plate 107, thus eliminating the need to disassemble the valve 101 to adjust the circumferential seal gap 160. The adjuster 180 may be a screw ranging in size from about M8 to M27. As the valve body fastener 168 is loosened, the movable adjuster 180, as shown in FIG. 6, is threaded into or out of the intermediate plate 170 to project a varying distance onto the valve body 109, thereby controlling the distance between the valve body 109 and the intermediate plate 170.

Fig. 5 and 6 also show a plurality of seals 172, 174, typically 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. The location of these seals may be different from that shown in the figures, and there may be more than one seal between the various components of the valve 101.

This configuration 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/collapsed configuration, a feeler gauge is 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 large, the seal gap 160 is reduced by rotating the adjustment fastener 180 counterclockwise. If the gap is too small, the seal gap 160 is increased by rotating the adjustment fastener 180 clockwise. Valve body fasteners 168 securing intermediate plate 170 to valve body 109 are loosened.

The tool is then used to rotate the adjuster 180 to provide the desired seal clearance 160. The gap 160 is then checked with a feeler gauge.

With the seal gap 160 set, the valve body fasteners 168 securing the intermediate plate 170 to the valve body 109 are retightened.

A feeler can be inserted at multiple locations around the circumference of the elastomeric seal 147 to determine the size of the gap. If the loosening is not sufficient to adjust the movable adjuster 180, the valve body fastener 168 of step 2 may be removed from the assembly. The plurality of movable adjusters 180 must be adjusted in a similar manner to ensure that the intermediate plate 170 and the valve body 109 remain aligned with one another along the longitudinal center axis 157. Ideally, the intermediate plate 170 and the connected components should be displaced from the valve body 109 at a right angle along the central axis 157 to ensure a consistent circumferential gap 160 between the convex sealing surface 138 and the sealing ring 147.

As can be appreciated, the above-described method is beneficial to the user because all of the fasteners 166, 168 and the movable adjuster 180 are accessible through the upper plate 107 and do not require removal of the upper plate 107 to adjust the circumferential seal gap 160. The new design allows the seal gap 160 to be set in a shorter time when compared to prior art valves. When performing maintenance on a large valve 101, components such as the upper plate 107 may be heavy and cumbersome to remove. Thus, the new design also requires less physical effort to set the seal gap 160 because the upper plate 107 does not need to be removed.

Another benefit of the new design is represented during valve maintenance because the resilient sealing ring 147 can be accessed by simply removing the valve upper plate 107. When the valve upper plate 107 is removed, both the sealing ring 147 and the retaining ring 164 may be lifted off the intermediate plate 170. There are no fasteners used to hold the seal ring 147 and the retaining ring 164 to the intermediate plate 170. When the sealing ring 147 is made of a flexible rubber compound, the sealing ring 147 surrounds the retaining ring 164.

This is beneficial because it allows the intermediate plate 170 to remain in the same position, thus maintaining a "factory set" circumferential seal gap 160.

The new adjustable design can be retrofitted to existing valves, allowing existing users to also benefit.

In fig. 5 and 6, the valve includes a valve upper plate 107, an intermediate plate 170, and a main body 109, but the disclosed invention may also function if there is no intermediate plate 170 and the resilient sealing ring 147 is mounted directly or indirectly to the upper plate 107. This configuration would result in the valve being assembled with only one set of fasteners, mounting the valve upper plate 107 to the valve body 109.

Fig. 7 is a cross-sectional view of the embodiment of fig. 5 and 6 rotated 90 degrees about a vertical axis. The transverse axis 156 is oriented into the plane of the paper and the closure member 137 rotates about that axis, moving between an open position and a closed position.

FIG. 8 is a detailed view of the seal ring 147 shown in the first configuration (expanded), with the seal gap 160 enlarged for clarity.

Fig. 9 is a detailed view of the seal ring 147 shown in a second configuration (collapsed), with the seal gap 160 enlarged for clarity.

While various exemplary embodiments have been disclosed, it should be understood that variations, modifications, and combinations of the valves and methods disclosed herein may be made without departing from the scope of the appended claims.