초록 ▼

A top entry ball valve (10) has a removable top plate (34) to permit the removal of a ball valve member (80). Valve seat assemblies (98, 100) each include a primary metal seat member (102), a concentric secondary elastomeric seat member (104), and a concentric rigid seat retainer 106. The primary me

A top entry ball valve (10) has a removable top plate (34) to permit the removal of a ball valve member (80). Valve seat assemblies (98, 100) each include a primary metal seat member (102), a concentric secondary elastomeric seat member (104), and a concentric rigid seat retainer 106. The primary metal seal member (104) has a free end portion (108) of a reduced thickness to engage the ball member (80) closely adjacent the bore (82). The valve ball member (80) is mounted for rotation on a lower trunnion (28) of the valve body (12) and an upper trunnion (40) of the top plate (34). A packing (70) about the stem (48) has a downward force exerted thereagainst by Belleville springs (74, 75) that is greater than the maximum internal pressure of the valve (10).

대표청구항 ▼

A top entry ball valve comprising: a valve body having a valve chamber therein and opposed inlet and outlet flow passages in fluid communication with the valve chamber; a top plate removably mounted on the valve body over the valve chamber to provide access to the valve chamber when removed; a spher

A top entry ball valve comprising: a valve body having a valve chamber therein and opposed inlet and outlet flow passages in fluid communication with the valve chamber; a top plate removably mounted on the valve body over the valve chamber to provide access to the valve chamber when removed; a spherical ball valve member having a central bore therethrough and mounted in said valve chamber for movement between open and closed positions relative to said flow passages, said ball valve member being insertable within and removable from said valve chamber upon removal of said top plate; an operating stem connected to said ball valve member and extending through said top plate; means connected to the extending end of said operating stem for rotating said ball valve member between open and closed positions; an annular recess in said valve body at the juncture of the valve chamber with each of the flow passages; an annular valve seat assembly mounted in each of the annular recesses about the adjacent flow passage for sealing about the spherical surface of the valve member and blocking fluid flow between the inlet and outlet flow passages in the closed position of the ball valve member; each valve assembly including a primary annular metal seat member having an extending free end portion positioned closely adjacent the central bore in said ball valve member in the open position thereof for sealing against the ball valve member, a separate secondary elastomeric seat member spaced radially outward of said primary metal seat member and in concentric relation thereto for forming a fluid tight sealing relation with said ball valve member, and a separate generally rigid retainer ring for the elastomeric seat member positioned radially outwardly of said primary seat member and restraining outward radial movement of said primary metal seal member; and means to urge said metal seal member continuously into sealing contact with said ball valve member.