Plug valve

• US 4,262,880 A
• Filed: 06/29/1979
• Issued: 04/21/1981
• Est. Priority Date: 06/29/1979
• Status: Expired due to Term

• Current Assignee: Nupro Co. (Swagelok Company)
• Original Assignee: Nupro Co. (Swagelok Company)
• Inventors: Danko, Oliver L., Steiss, William C., Tobbe, William P., Shufflebarger, Earl D., Gardner, Thomas J., Amor, William H. Jr.
• Primary Examiner(s): Cohan, Alan
• Assistant Examiner(s): Spiegel, H. Jay
• Application Number:
  US06/053,549
• Time in Patent Office: 662 Days
• Field of Search: 251/288, 251/209, 251/309, 251/317, 251/DIG. 1
• US Class Current: 251/288
• CPC Class Codes: F16K 5/0407 with particular plug arrangements, e.g. particular shape or built-in means
• CPC Class Codes: F16K 5/12 Arrangements for modifying the way in which the rate of flow varies during the actuation of the valve
• CPC Class Codes: Y10S 251/90 Valves with o-rings

Abstract

A plug valve having a valve body with a cylindrical plug receiving opening extending therethrough having at least one terminal end thereof outwardly chamfered. Fluid inlet and outlet passageways communicate with the receiving opening and are chamfered at the areas of communication therewith. A plug member includes a cylindrical plug portion closely received in the body receiving opening. This plug portion has a transverse fluid flow passage which is selectively rotatable into and out of alignment with the valve body inlet and outlet passageways. Axially spaced apart circumferential sealing members disposed on both sides of the flow passage prevent fluid flow outwardly of the receiving opening. An inlet passageway sealing means disposed in the plug portion side wall intermediate the opposite flow passage ends sealingly surrounds the passageway in the valve closed position. A fluid relief channel communicating between the flow passage and plug portion side wall relieves fluid pressure through the outlet passageway as the valve is moved to the closed position. The plug portion advantageously includes a thin coating of plastic material for enhancing its fluid sealing relationship with the receiving opening and for improving ease of rotation between the valve opened and closed positions. The plug member is axially retained in position in the receiving opening by a snap ring at one end and by a handle at the other end. The handle is rotatable only between positively defined maximum valve opened and closed positions. Spaced apart circumferential grooves included in the plug portion side wall receive the axially spaced apart sealing members and at least the bottom walls of these grooves are also coated with the plastic material.

Claims

1. A plug type valve comprising:

a valve body having a generally cylindrical plug member receiving opening therethrough between opposite actuating and locking end faces, fluid inlet and outlet openings communicating with said opening generally radially thereof, a plug member including a generally cylindrical plug portion rotatably received in said valve body opening and having an outer surface, opposite actuating and locking ends, and a lateral flow passage therethrough with inlet and outlet ends, circumferential seal receiving grooves in said outer surface adjacent said actuating and locking ends, seals received in said seal receiving grooves and being in sealing engagement with the periphery of said plug member receiving opening, said locking end of said plug portion extending outwardly beyond said locking face on said valve body and having a circumferential snap ring groove therein removably receiving a snap ring extending outwardly in overlapping relationship to said locking end face, a continuous groove in said outer surface intermediate said seal receiving grooves and said inlet and outlet ends, a continuous seal received in said continuous groove and being in sealing engagement with the periphery of said valve body opening, said continuous seal encompassing a closed seal area for sealingly surrounding said inlet passageway, a pressure relief groove extending generally circumferentially of said plug portion from said outlet end of said flow passage over a small arc in said outer surface located on the opposite side of said inlet and outlet ends from said continuous groove, said outer surface of said plug portion being smooth and ungrooved adjacent said inlet and outlet ends of said flow passage except for said pressure relief groove, a manual actuator on said plug member at said actuating end and including a generally flat actuator face extending outwardly beyond said plug portion outer surface in overlapping relationship to said actuating end face on said valve body, said actuator face having a recess therein with opposite recess ends defining stop surfaces, a projection on said valve body extending into said recess for cooperation with said stop surfaces to limit rotation of said valve body between a closed position in which said continuous seal surrounds said inlet passageway and an open position in which said inlet and outlet ends of said flow passage are in fluid communication with said inlet and outlet passageways, said pressure relief groove passing across said outlet passageway subsequent to complete movement of said inlet end past said inlet passageway during movement of said plug portion from said open position toward said closed position, and said recess and projection cooperating for providing complete insertion of said plug portion through said valve body opening for positioning a snap ring in said snap ring groove only when said plug portion is properly rotatably oriented for insuring alignment of said continuous seal in surrounding relationship with said inlet passageway and of said inlet and outlet ends respectively with said inlet and outlet passageways when said plug portion is rotated between said closed and open positions.

2. The valve as defined in claim 1 wherein said outer surface of said plug portion between said circumferential seal receiving grooves is roughened for good adhesion of a coating thereto and is coated with a thin layer of plastic material having a smooth outer surface and a low coefficient of friction, said circumferential seal receiving grooves being smooth and unroughened and being at least partly coated with said plastic material.

3. The valve as defined in claim 2 wherein said valve body plug receiving opening has a longitudinal axis and said inlet and outlet passageways enter said plug receiving opening at outwardly chamfered inlet and outlet openings, said inlet and outlet passageways having centerlines substantially intersecting said axis, each said inlet and outlet opening having opposite portions on opposite sides of said centerlines in directions parallel to said axis which are outwardly chamfered about a first radius intersecting each said centerline, and each said inlet and outlet opening having opposite portions on opposite sides of said centerlines in directions around said axis which are outwardly chamfered about a second radius intersecting each said centerline and being substantially smaller than said first radius, said chamfered openings having inner edges positioned inwardly away from the periphery of the valve body opening whereby abrading of the continuous seal on the edges as the continuous seal moves thereacross is avoided.

4. The valve as defined in claim 1 wherein said continuous groove has generally parallel inner and outer side walls and a bottom wall, said inner wall having a depth greater than said outer wall and said bottom wall being out of perpendicular relationship to said inner and outer walls by being sloped away from said plug portion outer surface in a direction from said outer wall toward said inner wall.

5. A body for a plug type valve comprising:

a valve body including a generally cylindrical plug receiving opening therethrough having a longitudinal axis, generally circular inlet and outlet passageways extending generally radially of said axis and entering said plug receiving opening at outwardly chamfered inlet and outlet openings, said passageways having centerlines substantially intersecting said axis, each said inlet and outlet opening having opposite portions on opposite sides of said centerlines in directions parallel to said axis which are outwardly chamfered about a first radius intersecting each said centerline, and each said inlet and outlet opening having opposite portions on opposite sides of said centerlines in directions around said axis which are outwardly chamfered about a second radius intersecting each said centerline and being substantially smaller than said first radius, said chamfered openings having inner edges positioned inwardly away from the periphery of the valve body opening whereby abrading of the continuous seal on the edges as the continuous seal moves thereacross is avoided.

6. The valve body of claim 5 wherein said first radius is longer than the radius of said plug receiving opening and said second radius is shorter than the radius of said plug receiving opening.

7. A plug member for a plug valve comprising:

an elongated generally cylindrical plug portion having an outer surface and opposite stem and locking ends, circumferential seal receiving grooves adjacent said stem and locking ends, seals received in said seal receiving grooves, a circumferential snap ring receiving groove in said outer surface between said locking end and said seal receiving groove which is adjacent said locking end, a lateral flow passage through said plug portion intermediate said seal receiving grooves and having inlet and outlet ends, a continuous groove in said outer surface intermediate said seal receiving grooves and intermediate said inlet and outlet ends, said continuous groove having generally parallel inner and outer side walls and a bottom wall, said inner side wall having a depth greater than the depth of said outer groove side wall such that said groove bottom wall tapers inwardly away from said plug portion outer surface in a direction from said outer groove side wall toward said inner groove side wall and does not extend perpendicular to either of said groove side walls, a continuous seal received in said continuous groove and encompassing a closed seal area for sealingly surrounding an inlet passageway in a plug valve body, a pressure relief groove in said outer surface extending from said outlet end of said flow passage over a short circumferential arc on the opposite side of said outlet end from said continuous groove, said outer surface being smooth and ungrooved adjacent said inlet and outlet ends of said flow passage except for said pressure relief groove, an integral stem extending outwardly from said stem end, a handle secured to said stem and having a generally flat face extending generally radially outwardly beyond said outer surface of said plug portion, a recess in said flat face for receiving a projection on a valve body, said recess having opposite stop surfaces spaced over an arc for cooperation with a projection on a valve body to limit rotation of said plug member over an angle generally the same as the angle between the center of said closed seal area and the center of said inlet end of said flow passage, and said recess and stop surfaces having a predetermined relationship to said inlet and outlet ends and said continuous seal for insuring proper installation of said plug portion in a plug body.

8. The plug member of claim 7 wherein said outer surface between said circumferential seal receiving grooves is coated with a thin layer of plastic material having a low coefficient of friction, said outer surface between said circumferential seal receiving grooves being roughened for enhancing adhesion of said plastic material thereto, and said circumferential seal receiving grooves being at least partially smooth and unroughened and being at least partly coated with said plastic material.

9. The plug member of claim 7 wherein said plug portion has a longitudinal axis and said outlet end of said flow passage has a centerline intersecting said axis, said pressure relief groove extending from said flow passage outlet end to a pressure relief groove end, a reference line extending from said axis to said pressure relief groove end forming an included angle of approximately 60°

with said centerline.

10. A plug type valve comprising:

a valve body having a generally cylindrical plug member receiving opening extending therethrough, fluid inlet and outlet passageways communicating with said opening generally radially thereof, a plug member including a generally cylindrical plug portion rotatably received in said valve body opening and having a lateral flow passage therethrough with inlet and outlet ends, said plug portion having an outer surface, a continuous groove in said outer surface intermediate said inlet and outlet ends, a continuous seal received in said continuous groove and engaging the peripheral surface of said valve body opening, said continuous seal encompassing an area greater than the area of said inlet passageway at said valve body opening, said plug member being rotatable between a closed position in which said continuous seal surrounds said inlet passageway for blocking flow therethrough and an open position in which said inlet and outlet ends of said flow passage are in fluid flow communication with said inlet and outlet passageways, said continuous groove having generally parallel inner and outer groove side walls and a groove bottom wall, said inner side wall having a depth greater than the depth of said outer wall such that said groove bottom wall tapers inwardly away from said plug portion outer surface in a direction from said outer groove side wall toward said inner groove side wall and is not perpendicular to either of said groove side walls.