Patent Application
20180335149
Not Applicable.
The disclosure relates to improvements for valve discs, stems, and assemblies, and in particular resilient butterfly valve and valve assemblies.
There is a need for butterfly valve disc-stem assemblies utilizing a disc-stem having no cavities, pins, or fasteners, and which feature improved control and flow characteristics.
The disclosure relates to a unitary disc-stem apparatus for a valve, which has a disc defining a circumference around the disc; a first hub integral to the disc; a second hub integral to the disc; a first stem portion joining the disc at the first hub and a second stem portion joining to the disc at the second hub; a curved extended edge which is transposed on opposite sides of the disc, wherein the curved extended edge is progressively longer moving circumferentially away from the first hub and the second hub along the circumference of the disc, and longest at a position where the opposite curved extended edges of the disc are along an axis perpendicular to the first stem portion and the second stem portion.
The disclosure further relates to the unitary or one piece disc/stem designed to have no cavities, pins or fasteners of any kind like typical two piece butterfly valve discs with a shaft running through the disc. The design allows for control bi-directionally—or as the fluid media flows in either directions. In addition, the design-feature allows for control and optimization of required torque while positioning the disc-stem for seating and unseating.
As used herein, the terms “rotational,” “rotating,” “rotatably”, or the like in regards to movement or motion shall refer to movement around or about an axis, as defined by the valve stem of the valve system.
The embodiments may be better understood, and numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings. These drawings are used to illustrate only typical embodiments of this invention, and are not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
The description that follows includes exemplary apparatus, methods, techniques, and instruction sequences that embody techniques of the inventive subject matter. However, it is understood that the described embodiments may be practiced without these specific details.
The design of this unitary disc-stem 30 may be completely symmetrical. Fluid can travel through the flow path 19 in both directions. The unitary disc-stem 30 allows a bi-directional control valve with the same control characteristic and flow curve when fluid travels in a pipe in either direction around this disc/stem.
The variable length of the disc extended edge 40 (for variable length see wedge-like region represented or defined between lines a-a, b-b and c-c; except that the true length 44 of extended edge 40 at each interstitial position around disc 32 is defined from one end of these lines to the opposite flat disc face 38 for example see line e-e) provides a variable area where during the stroke of the disc 32 from closed to open, the variable area between the disc edge 40 and the valve body seat 20 is extended where the area is largest at the disc edge 40 perpendicular to the stem 18 at the outer edges of the disc 36, which creates a longer and straightening path for the fluid. This accelerates the fluid more gradually, creating a Venturi effect variable through the circumference of the disc edge 40, and spreading the flow and velocity more evenly around the disc opening (defined between the disc edge 40 and the seat 20 and variable depending upon the rotational position of the disc 32 relative to the seat 20) and further increasing rangeability.
Controlling the pressure drop and fluid velocity only at the edge of the disc 40 is very important since any other shape on the disc 32 makes the control characteristic less than ideal. Therefore, the need to use a flat or planar disc face 38 without a hump where you would typically see a shaft running through the valve disc, bolts, or offset shafts from the sealing edge is very important. This assures that the flow characteristic of the disc 32 is controlled at the disc edge 40 and can be shaped for any control characteristic from equal percentage, linear or any other characteristic required.
The disc edge 40 can be spherically shaped 40B and the sphere center offset from the center of the disc so a portion of the edge 40 is always in contact with the seat 20 and the edge 40 can be shaped to include a characterized shape.
The disc edge 40 can be shaped and positioned to minimize seat 20-disc 32 interference while achieving zero flow at spherically machined disc edge 36 which is concentric to the disc stem shaft throughout the lifecycle of the valve 10. This assures low-torque requirements throughout the valve's life.
The unitary disc-stem 30 may be designed to have no cavities, pins or fasteners of any kind. This design without fasteners is suited for use in pharmaceutical, food or any sanitary service where a smooth valve control element is essential in creating a final control element with the best control characteristics without the typical high acceleration through a conventional butterfly valve disc, resulting in high velocity on the disc edge and subsequent disturbance of the fluid and cavitation. This is important in certain processes where control is important and higher than acceptable pressure drop exists for a typical butterfly valve and where that process physical state cannot be altered through the valve 10 through better control at the initial angle of opening through most of its travel. The design allows for this type of control bi-directionally—or as the fluid media flows in either directions. In addition, the design-feature allows for control and optimization of required torque while positioning the disc/stem for seating and unseating.
While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions and improvements are possible. For example, the techniques used herein may be applied to any valve system or assembly used for piping systems. Additionally, the valve assembly 10 may be used on any size of valve and, moreover, the figures included within this disclosure depict merely some exemplary embodiments. By way of example, the valve body 12 may be of a wafer style, lug style or double flanged style. On double flanged style valves, the width of the body 12 may be much larger than wafer and lug style valves that have the same width; this may mean the seat 40 may be adjusted or “stretched”, however the performance and features mentioned in this disclosure will be the same.
Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter.
| Number | Date | Country | |
|---|---|---|---|
| 62507608 | May 2017 | US |
