Dual seal fire safe stem packing orientation

A packing assembly for sealing an annular space between a valve stem with an axis and a valve body assembly, the packing assembly comprising:

• a first packing retainer having a collar with a first end surface, and a first retainer body defining an inner cavity with a bottom surface, the collar having a smaller outer diameter than the first retainer body;
• a first stem packing, the first stem packing located axially between the first end surface of the collar of the first packing retainer and the valve body assembly and forming a seal between the valve stem and the valve body assembly;
• a fire resistant stem packing located in the inner cavity of the first packing retainer;
• a second packing retainer that limits axial movement of the fire resistant stem packing;
• and
• a piston member located axially between the first stem packing and the fire resistant stem packing, the piston member being moveable to apply axial force to one of the first stem packing and the fire resistant stem packing.

A method of sealing a valve with a packing assembly, the method comprising:

• providing a valve having:
• a valve body assembly defining a flow passage and a body cavity perpendicular to the flow passage, the valve body assembly further defining a bore extending from an exterior of the valve body assembly into the body cavity, the bore having an second bore portion with an enlarged diameter defined by an inner surface of the bore;
• and
• a valve stem extending from the body cavity to an exterior of the valve body assembly through the bore for moving a valve member from a closed position to an open position, the valve stem having an axis;
• circumscribing a first portion of the valve stem with a first stem packing, forming a seal between the valve stem and the valve body assembly in the second bore portion;
• limiting axial movement of the first stem packing with a first packing retainer having a collar and having a first retainer body defining an inner cavity;
• circumscribing a second portion of the valve stem with a second stem packing located in the inner cavity of the first packing retainer;
• limiting axial movement of the second stem packing with a second packing retainer;
• and
• locating a piston member axially between the first stem packing and the second stem packing, the piston member being moveable to apply axial force to one of the first stem packing and the second stem packing.