| 主权项 |
1. A ball valve comprising:
a. a ball valve body having a first valve bore and a second valve bore; b. a ball situated within the ball valve body, said ball comprising a throughbore defining a flow axis; c. a first trunnion bonnet with a proximal end oriented toward the ball and a distal end oriented away from the ball, the trunnion bonnet further defining a trunnion axis perpendicular to the flow axis; d. an outer packing retainer having a proximal end and a distal end, the outer packing retainer adapted to be received by the first trunnion bonnet, an annular space being formed between the outer surface of the outer packing retainer and an inner surface of the first trunnion bonnet; e. an inner packing retainer having a proximal end and a distal end, the inner packing retainer adapted to be received by the outer packing retainer, an annulus being formed between the inner surface of the outer packing retainer and the outer surface of the inner packing retainer; f. a first sealing system between the proximal end of the trunnion bonnet and positioned proximally to the outer packing retainer, wherein the first sealing system comprises a U-pack seal and a polypack seal in stacked relationship to one another; g. a second sealing system between the proximal end of the outer packing retainer and the proximal end of the inner packing retainer, wherein the second sealing system comprises two polypack seals in stacked relationship to one another; h. a trunnion with a proximal end abutting the ball and extending distally from the ball through each of the trunnion bonnet, the first sealing system, the outer packing retainer, the second sealing system and the inner packing retainer, the trunnion further having a distal end connected to a turnwheel; and wherein the first sealing system prevents fluid from escaping from the ball valve, and wherein if the first sealing system fails, the second sealing system prevents fluid from escaping from the ball valve. |
