| 摘要 |
A pressure seal assembly for use in a high pressure control device for sealing a bonnet assembly that is removably received by an access port defined by a body portion of the high pressure control device. The seal assembly inhibits leakage between the body portion and the bonnet assembly and includes an annular graphite gasket that has a tapered portion defining an angled surface engageable with a complementally-formed angled surface on the bonnet assembly. A first anti-extrusion ring associated with the tapered portion of the annular graphite seal is urged into sealing engagement with a surface defined by the access port when clamping pressure is applied to the annular graphite gasket. A pair of inner and outer anti-extrusion rings, are urged into sealing contact with an access port surface and bonnet assembly surface, respectively, when the clamping force is applied to the gasket. The rings are urged by camming surfaces, which may be defined by the annular graphite gasket and/or a thrust washer. The bonnet assembly includes a reduced diameter section which at least partially defines a seal assembly receiving cavity between the bonnet assembly and the body portion. The anti-extrusion rings include overlapped ends, which allow expansion and contraction while maintaining overlapping contact with the ends of the rings. When the camming surfaces are defined by the annular graphite gasket, the surfaces may include retaining segments which operate to maintain the inner and outer extrusion rings in an assembled relation prior to installation. |
