Valve ball configuration

Details Valve ball configuration Valve ball configuration

1999-06-30

2001-01-16

Shaver, Kevin (Department: 3754)

Valves and valve actuation

Balanced valves

Rotary

C251S315160

Reexamination Certificate

active

06173940

ABSTRACT:

BACKGROUND OF THE INVENTION
This application relates to the art of ball valves and, more particularly, to a physical configuration of a valve ball that minimizes fluid pressure forces tending to rotate the ball when it is partly open. Although the invention will be shown and described with reference to a ball valve that has two seals, it will be appreciated that the improvements can be used in ball valves that have one seal.
Ball valves are used to control or throttle flow rates by adjusting the valve ball to a partly closed position. Fluid pressure acting on the valve ball tends to rotate the valve ball out of its desired position and undesirably change the flow rate. Therefore, braking or locking mechanisms are required to positively hold the valve ball in a desired position for maintaining a substantially constant throttled flow rate. These mechanisms may include manually engaged locks, braking mechanisms that are engaged by movement of the valve ball without an input to the adjustment handle, or adjustment mechanisms that provide inherent braking action such as a worm gear drive. Minimizing the fluid pressure forces that tend to move the valve ball from its desired position would make it possible to simplify or eliminate the locking or braking mechanisms.
SUMMARY OF THE INVENTION
In accordance with the present application, a valve ball is physically configured to minimize rotational forces imparted thereto by fluid pressure acting thereon when the ball is in a partly closed position for regulating the flow rate therethrough. In part, the physical configuration that minimizes the undesired forces includes a hollowed out ball interior and recessed areas on the ball outer surface that allow fluid flow past the exterior of the ball when it is between approximately ¼-¾ open.
In one arrangement, the exterior surface of the valve ball is generally spherical with opposite recessed areas that provide fluid flow past the valve ball seals and around the outer periphery of the ball when it is partly open. The recessed areas have outer surface profiles that preferably are substantially flat and substantially circular. A passage through the ball has a passage periphery that defines a valve ball inner surface that is provided with inner surface profiles located opposite from and substantially corresponding in size and shape to the outer surface profiles.
In a preferred arrangement, the ball has inner and outer surfaces that are geometrically similar except in the vicinity of the intersection of the ball rotational axis with the ball inner and outer surfaces.
In accordance with another aspect of the application, the valve ball is hollowed out so that the passage through the valve ball is enlarged between the passage inlet and outlet openings. In a preferred arrangement, the interior surface shape of the valve ball is substantially the same as the external surface shape of the valve ball so that the wall thickness between the inner and outer surfaces is substantially uniform.
The passage through the valve ball has circular inlet and outlet openings of the same diameter. The circular flat areas on the external surface of the ball may have a diameter that is 55-85% of the passage inlet/outlet opening diameter and more preferably 70-80% of such diameter. The circular flat areas also have a diameter that may be between 35-55% of the diameter of the generally spherical valve ball.
It is a principal object of the present invention to provide an improved valve ball configuration.
It is another object of the invention to provide a valve ball that is configured to minimize fluid pressure forces that tend to rotate the ball out of a desired partly closed position.
It is also an object of the invention to provide an improved valve ball that is economical to manufacture.
It is an additional object of the invention to provide an improved valve ball having both external and internal configurations that aid in minimizing fluid pressure forces that tend to rotate the valve ball from a desired position.
It is another object of the invention to provide a valve ball that is configured to have a more balanced distribution of fluid pressure forces acting thereon with respect to the ball rotational axis.
It is a further object of the invention to provide a valve ball configuration that minimizes pressure forces tending to close the ball when it is in a throttling position.


REFERENCES:
patent: 2545220 (1951-03-01), Wolcott, Jr.
patent: 2765142 (1956-10-01), Ludeman
patent: 3689027 (1972-09-01), Grenier
patent: 3722859 (1973-03-01), Murphy et al.
patent: 3784155 (1974-01-01), Tomlin
patent: 4103868 (1978-08-01), Thompson
patent: 4423749 (1984-01-01), Schmitt
patent: 4542878 (1985-09-01), Kulisek
patent: 5435521 (1995-07-01), Jarecki
patent: 5979873 (1999-11-01), Wu

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