Ball valve with single piece packing

• US 20060060810A1
• Filed: 01/17/2003
• Published: 03/23/2006
• Est. Priority Date: 01/18/2002
• Status: Active Grant

• Current Assignee: Swagelok Company
• Original Assignee: Swagelok Company
• Inventors: Kvarda, Eric M, Gotch, James E, Lippucci, Thomas A, Fry, Brandon J, Timko, Jared S
• Granted Patent: US 7,887,024 B2
• Time in Patent Office: Days
• US Class Current: 251/314
• CPC Class Codes: F16K 11/0873 the plug being only rotatable around one spindle
• CPC Class Codes: F16K 27/067 with spherical plugs
• CPC Class Codes: F16K 5/0636 the spherical plug being insertable from the top of the housing
• CPC Class Codes: F16K 5/0668 Single packings
• CPC Class Codes: F16K 5/0684 on the plug
• CPC Class Codes: F16K 5/0689 between housing and plug
• CPC Class Codes: F16K 5/0694 Spindle sealings
• CPC Class Codes: Y10T 137/0508 Ball valve or rotary ball valve

Abstract

A ball valve includes a valve element (22) and a single piece packing (32) that seals the valve element within a valve cavity (20). The single piece packing is called over the valve element at room temperature or may be molded n. The valve element may include a flow control element such as a ball (24) and upper (28) and lower (30) trunnions. The various dimensions of the valve element and packing are selected to facilitate room temperature assembly and to substantially reduce the volume of packing material, thereby improving the performance of the valve over wider temperature ranges and pressure ratings.

Claims

1-34. -34. (canceled)

35. A valve comprising:

a valve body having a valve cavity therein;

a valve element for controlling flow through the valve based on rotational position of the valve element about an axis, and

a packing that surrounds said valve element and seals said valve element within said valve cavity;

wherein said valve element comprises a ball and adjacent upper and lower trunnions;

said lower trunnion extending axially past a lower end of said packing;

said valve cavity being dimensioned to closely receive said valve element while permitting said valve element to axially shift to compensate for temperature effects on said packing.

36. The valve of claim 35 wherein the packing is a single piece packing that is dimensioned to be installed on said valve element within a room temperature range.

37. The valve of claim 36 wherein said room temperature range is about 65-100°

F.

38. The valve of claim 36 wherein said packing has a generally cylindrical outer surface defined by a height H and an outer diameter D4, said packing having a ratio H/D4 of about 0.75 to about 0.85.

39. The valve of claim 38 wherein said ratio H/D4 is about 0.8.

40. The valve of claim 35 wherein said ball has an outer diameter D1 and at least one of said trunnions having an outer diameter D3;

wherein said valve element has a ratio D3/D1 of about 0.7 to about 0.9.

41. The valve of claim 40 wherein said ratio D3/D1 is about 0.8.

42. The valve of claim 36 wherein said packing has a generally cylindrical outer surface defined by a height H and an outer diameter D4, said packing having a ratio H/D4 of about 0.75 to about 0.85;

and wherein said ball has an outer diameter D1 and at least one of said trunnions having an outer diameter D3;

wherein said valve element has a ratio D3/D1 of about 0.7 to about 0.9.

43. The valve of claim 42 wherein said ratio H/D4 is about 0.8 and said ratio D3/D1 is about 0.8.

44. The valve of claim 35 wherein said packing comprises a polymer.

45. The valve of claim 44 wherein said polymer is selected from the group comprising polytetrafluoroethylene (PTFE), polyethylene, polyetheretherketone (PEEK) and fluorinated ethylene propylene.

46. The valve of claim 35 wherein said valve element comprises a non-spherical flow control element.

47. The valve of claim 36 wherein said packing has an inner surface that forms an interference fit with said valve element when said packing is installed thereon prior to loading said packing within said valve body.

48. The valve element of claim 36 wherein said packing has an interference fit with said valve cavity when said packing is installed on said valve element and inserted into said valve cavity prior to loading said packing within said valve cavity.

49. The valve of claim 35 wherein said packing comprises a polymer that is selected from the group consisting of:

PFA, filled PFA, polytetrafluoroethylene (PTFE), filled PTFE, polyethylene, polyetheretherketone (PEEK) and fluorinated ethylene propylene.

50. The valve of claim 35 wherein said packing is dimensioned to be installed on said valve element at a temperature below which said packing deforms.

51. The valve of claim 50 wherein said temperature is room temperature.

52. The valve of claim 50 wherein said packing is a single piece packing.

53. The valve of claim 50 wherein said packing is over molded onto said valve element.

54. The valve of claim 35 wherein said packing is a multi-piece packing.

55. The valve of claim 35 wherein said ball has an outer diameter D1 and at least one of said trunnions having an outer diameter D3;

wherein said valve element has a ratio D3/D1 that facilitates assembly of said packing onto said valve element at room temperature.

56. The valve of claim 35 wherein said valve cavity comprises a reduced diameter bore that receives said lower trunnion and prevents packing material from creeping below said lower trunnion.

57. The valve of claim 35 wherein said packing is live loaded.

58. The valve of claim 35 wherein said packing comprises a plastic polymer.

59. The valve of claim 35 wherein said polymer comprises PTFE.