Extreme service plug valve

Abstract

A valve assembly for managing a flow of fluids in hydrocarbon development and production operations includes a valve body having an internal body cavity and a body bore intersecting the body cavity. A valve plug is located within the body cavity and is rotatable between an open position and a closed position. A sleeve is located between the valve plug and the valve body and is rotationally fixed to the valve body and remains rotationally static relative to the valve body as the valve plug rotates. A seal groove is located on a sidewall surface of the sleeve and circumscribes one of the sleeve openings. A seal assembly has a seal ring that is U shaped in cross section with an inner leg that engages the seal groove and an outer leg that extends out of the seal groove and engages one of the valve body and the valve plug.

1 . (canceled) 
     
     
         2 . A valve assembly for managing a flow of fluids in hydrocarbon drilling, production and processing operations, the valve assembly comprising:
 a valve body having an internal body cavity, a valve aft opening, and a body bore extending through the valve body and intersecting the body cavity;   a valve plug located within the body cavity, the valve plug having a plug through bore and being rotatable between an open position where the plug through bore registers with the body bore and a closed position where the valve plug prevents a flow of a fluid through the body bore;   a sleeve located between the valve plug and the valve body, the sleeve having a central bore and a pair of sleeve openings through a sidewall of the sleeve that align with the body bore, the sleeve being rotationally fixed to the valve body so that the sleeve remains rotationally static relative to the valve body as the valve plug rotates within the sleeve between the open position and the closed position;   a seal groove located on a sidewall surface of the sleeve, the seal groove circumscribing one of the sleeve openings;   a valve aft cover to cover the valve aft opening, the valve aft cover sealingly engaging the valve body; and   a seal assembly located within the seal groove, the seal assembly having a seal ring being U shaped in cross section with an inner leg that engages the seal groove and an outer leg that extends out of the seal groove and engages one of the valve body and the valve plug.   
     
     
         3 . The valve assembly according to  claim 2 , further including a valve stem extending from the valve plug through the valve body, the valve stem being a separate member from the valve plug, wherein the valve plug is operable to float within the sleeve. 
     
     
         4 . The valve assembly according to  claim 2 , further including a bearing assembly, the bearing assembly circumscribing a valve stem that extends from the valve plug through the valve body, the bearing assembly being releasably secured to the valve body and engaging a shoulder of the valve stem. 
     
     
         5 . The valve assembly according to  claim 2 , further including a coating on an outer surface of the sleeve, the coating varying in thickness over a coverage area on the outer surface of the sleeve. 
     
     
         6 . The valve assembly according to  claim 2 , further including a coating on an inner surface of the sleeve, the coating varying in thickness over a coverage area on the inner surface of the sleeve. 
     
     
         7 . The valve assembly according to  claim 2 , wherein the seal assembly includes a metallic seal in engagement with the seal ring, the metallic seal having a polymer coating. 
     
     
         8 . The valve assembly according to  claim 2 , wherein the sleeve is expandable in a hoop direction, the sleeve having one or more axially oriented cuts extending from a surface of the sleeve into the sidewall of the sleeve. 
     
     
         9 . A method of forming a valve assembly for managing a flow of fluids in hydrocarbon drilling, production and processing operations, the method comprising:
 using a valve body having an internal body cavity, a valve aft opening, and a body bore extending through the valve body and intersecting the body cavity;   using a sleeve having a central bore and a pair of sleeve openings through a sidewall of the sleeve;   forming a pair of seal grooves on a sidewall surface of the sleeve, each seal groove circumscribing one of the sleeve openings;   locating a seal assembly within the seal groove, the seal assembly having a seal ring that is U shaped in cross section;   locating a valve plug within the sleeve, the valve plug having a plug through bore;   passing the sleeve and the valve plug through the valve aft opening;   rotationally fixing the sleeve within the valve body so that the pair of sleeve openings align with the body bore, and so that an inner leg of the seal ring engages the seal groove and an outer leg of the seal ring extends out of the seal groove and engages one of the valve body and the valve plug, and so that the valve plug is rotatable between an open position where the plug through bore registers with the body bore and a closed position where the valve plug prevents a flow of a fluid through the body bore, the sleeve remaining rotationally static relative to the valve body as the valve plug rotates within the sleeve between the open position and the closed position; and   securing a valve aft cover to cover the valve aft opening, the valve aft cover sealingly engaging the valve body.   
     
     
         10 . The method according to  claim 9 , further comprising circumscribing a valve stem that extends through the valve body with a bearing assembly, the bearing assembly being releasably secured to the valve body and engaging a shoulder of the valve stem. 
     
     
         11 . The method according to  claim 9 , further comprising coating an outer surface of the sleeve with a coating, the coating varying in thickness over a coverage area on the outer surface of the sleeve. 
     
     
         12 . The method according to  claim 9 , further comprising coating an inner surface of the sleeve with a coating, the coating varying in thickness over a coverage area on the inner surface of the sleeve. 
     
     
         13 . The method according to  claim 9 , further comprising providing the sleeve with an area adjacent to the sleeve opening that circumscribes the sleeve opening that has a reduced sidewall thickness. 
     
     
         14 . The method according to  claim 9 , further comprising providing the sleeve that is unsymmetrical about a central axis, the sleeve having multiple inner diameters. 
     
     
         15 . The method according to  claim 9 , further comprising forming axially oriented cuts in the sleeve, the cuts extending from a surface of the sleeve into the sidewall of the sleeve, so that the sleeve is expandable in a hoop direction. 
     
     
         16 . A method of managing a flow of fluids in hydrocarbon drilling, production and processing operations with a valve assembly, the method comprising:
 using a valve body having an internal body cavity, a valve aft opening, and a body bore extending through the valve body and intersecting the body cavity;   using a valve plug within the valve body, the valve plug having a plug through bore;   using a valve aft cover to cover the valve aft opening, the valve aft cover sealingly engaging the valve body;   rotationally fixing a sleeve in the valve body between the valve body and the valve plug, the sleeve having a central bore, a pair of sleeve openings through a sidewall of the sleeve, and a seal assembly located within each of a pair of seal grooves on a sidewall surface of the sleeve, each seal groove circumscribing one of the sleeve openings and, wherein the seal assembly has a seal ring that is U shaped in cross section with an inner leg of the seal ring engaging the seal groove and an outer leg of the seal ring extending out of the seal groove and forming a seal with one of the valve body and the valve plug; and   rotating the valve plug between an open position where the plug through bore registers with the body bore and a closed position where the valve plug prevents a flow of a fluid through the body bore.   
     
     
         17 . The method according to  claim 16 , further comprising transferring an axial force of a valve stem that extends from the valve plug through the valve body with a bearing assembly, the bearing assembly being releasably secured to the valve body and including a thrust bearing that engages a shoulder of the valve stem. 
     
     
         18 . The method according to  claim 16 , further comprising providing a coating on an outer surface of the sleeve, the coating varying in thickness over a coverage area on the outer surface of the sleeve. 
     
     
         19 . The method according to  claim 16 , further comprising providing a coating on an inner surface of the sleeve, the coating varying in thickness over a coverage area on the inner surface of the sleeve. 
     
     
         20 . The method according to  claim 16 , further comprising providing an area of the sleeve adjacent to the sleeve opening that circumscribes the sleeve opening with a reduced sidewall thickness. 
     
     
         21 . The method according to  claim 16 , further comprising providing one or more axially oriented cuts in the sleeve, the cuts extending from a surface of the sleeve into the sidewall of the sleeve so that the sleeve is expandable in a hoop direction.