Top-entry ball valve assembly having camming surfaces

• US 20030193036A1
• Filed: 04/12/2002
• Published: 10/16/2003
• Est. Priority Date: 04/12/2002
• Status: Active Grant

• Current Assignee: Jeff Mike
• Original Assignee: Jeff Mike
• Inventors: Mike, Jeff
• Granted Patent: US 6,681,793 B2
• Time in Patent Office: Days
• US Class Current: 251/315.01
• CPC Class Codes: F16K 5/0636 the spherical plug being insertable from the top of the housing
• CPC Class Codes: F16K 5/201 with the housing or parts of the housing mechanically pressing the seal against the plug
• CPC Class Codes: Y10T 137/0508 Ball valve or rotary ball valve

Abstract

A top-entry ball valve assembly that includes top and bottom camming plates which are coupled to top and bottom shoulders of the ball valve member. The camming plates include a first pair of opposing camming corner-surfaces to displace the spring-biased valve seat from the perimeter of the ball valve member when it is rotated between open and closed positions. The plates further include a second pair of opposing camming corner-surfaces to fully retract the spring-biased valve seat when being serviced so that the retraction tool can be inserted to hold the seats in place with little or no damage to the forward end of the seats.

Claims

1. A ball valve assembly comprising:

a ball valve member having a stem;

a pair of spring-biased valve seats adapted to be retracted; and

,

a pair of camming plates fixedly couple to the top and bottom of the ball valve member about the stem and which rotate in unison with said stem, each camming plate includes a pair of opposing camming corner-surfaces for retracting the spring-biased valve seats a predetermined distance as the ball valve member is rotated between open and closed positions.

2. The assembly of claim 1, wherein said each camming plate further comprises:

a second pair of opposing camming corner-surfaces for retracting the spring-biased valve seats a second predetermined distance wherein the second predetermined distance is greater than said predetermined distance.

3. The assembly of claim 2, further comprising:

a top-entry ball valve housing;

a bonnet removably coupled to the housing;

a stop plate coupled to said stem exterior to said housing;

a stop screw coupled to said bonnet to limit the rotation of said stop plate as said stem is rotated between said open position and said closed position.

4. The assembly of claim 3, wherein removal of said stop plate and said stop screw allows said stem to be rotated so that said second pair of opposing camming corner-surfaces for retract said spring-biased valve seats said second predetermined distance.

5. The assembly of claim 2, wherein said each camming plate is a quasi-square shaped plate with truncated corners wherein the first pair of opposing camming corner-surfaces has a first arc-length and a first radius measured from a longitudinal axis of said stem to a center of said first arc-length;

and said second pair of opposing camming corner-surfaces has a second arc-length and second radius measured from said longitudinal axis of said stem to a center of said second arc-length.

6. The assembly of claim 5, wherein the truncation creates a slightly curved corner so that as said ball valve member is rotated about said stem, the camming operations are smooth.

7. The assembly of claim 1, wherein said each camming plate further includes:

two pairs of opposing parallel sides which are essentially straight and a first pair of opposing parallel sides is designed to abut in direct surface-to-surface contact with a forward annular flange of said spring-biased seats when the ball valve member is in its open position.

8. The assembly of claim 7, wherein a second pair opposing parallel sides is designed to abut in direct surface-to-surface contact with a forward annular flange of said spring-biased seats when the ball valve member is in its closed position.

9. The assembly of claim 1, wherein said ball valve member is sealed in said spring-biased seat when in said open position.

10. A method of minimizing wearing in a ball valve assembly comprising the method steps of:

retaining valve seats in sealing engagement with a ball valve member when the ball valve member is open; and

,

simultaneously, while rotating said ball valve member to a closed position, applying an opposing camming corner-surfaces to the valve seats to retract and displace the valve seats to thereby minimize surface-to-surface contact and wearing.

11. The method of claim 10, further comprising the method steps of:

removing a stop plate and stop screw;

simultaneously, while rotating said ball valve member, applying second opposing camming corner-surfaces to the valve seats to fully retract and displace the valve seats;

removing a retraction maintaining screw and seal from a port; and

,

inserting a retraction maintaining tool in said port.

12. The method of claim 11, further comprising the step of:

rotating said ball valve member to remove the second opposing camming corner-surfaces from the valve seats;

holding the valve seats fully retracted with said retraction maintaining tool; and

,

removing the ball valve member.

13. A ball valve assembly comprising the method steps of:

ball valve member;

valve seats;

means for retaining said valve seats in sealing engagement with the ball valve member when the ball valve member is in a open position;

means for rotating said ball valve member to a closed position; and

,

means for applying an opposing camming corner-surfaces to said valve seats to retract and displace said valve seats to minimize surface-to-surface contact and wearing.

14. The assembly of claim 13, further comprising:

means for limiting rotation of said ball valve member;

wherein said means for applying said opposing camming corner-surfaces to said valve seats includes means for applying second opposing camming corner-surfaces to the valve seats to fully retract and displace the valve seats.

15. The assembly of claim 14, further comprising:

means for holding said valve seats fully retracted even after the application of said second opposing camming corner-surfaces is removed.

16. The assembly of claim 15, wherein said applying means comprises a quasi-square shaped plate with truncated corners wherein said opposing camming corner-surfaces has a first arc-length and a first radius measured from a longitudinal axis of said ball valve member to a center of said first arc-length;

and the second opposing camming corner-surfaces has a second arc-length and second radius measured from said longitudinal axis of said stem to a center of said second arc-length.

17. The assembly of claim 16, wherein the truncation creates a slightly curved corner so that as said ball valve member is rotated the camming operations are smooth.

18. The assembly of claim 16, wherein said plate further includes:

two pairs of opposing parallel sides which are essentially straight and a first pair of opposing parallel sides is designed to abut in direct surface-to-surface contact with a forward annular flange of said seats when the ball valve member is in its open and closed position.