Abstract: A technique facilitates improved sealing with respect to safety valve pistons so as to improve reliable safety valve operation. According to an embodiment, a safety valve piston seal assembly is positioned about a safety valve piston and comprises components which divert a load path to the safety valve piston rather than to susceptible components of the seal assembly. For example, the seal assembly may comprise a load ring and spacers to energize a V-ring when pressure is applied to a metal spring energized (MSE) seal. However, the components are arranged so the load path is diverted to the safety valve piston when pressure occurs behind the V-ring instead of allowing the loading to act against the MSE seal.

Abstract: A technique facilitates improved sealing with respect to safety valve pistons so as to improve reliable safety valve operation. According to an embodiment, a safety valve piston seal assembly is positioned about a safety valve piston and comprises components which divert a load path to the safety valve piston rather than to susceptible components of the seal assembly. For example, the seal assembly may comprise a load ring and spacers to energize a V-ring when pressure is applied to a metal spring energized (MSE) seal. However, the components are arranged so the load path is diverted to the safety valve piston when pressure occurs behind the V-ring instead of allowing the loading to act against the MSE seal.

Abstract: An endoscopic surgical instrument for performing a procedure inside a patient. The instrument includes a handle assembly including a grip for holding the instrument and controls for controlling movement of the instrument. An elongate shaft having a grip end is mounted on the handle assembly. The shaft has a working end opposite the grip end. The shaft has a proximal portion adjacent the grip end and a distal portion adjacent the working end. The proximal portion has a centerline and is selectively rotatable with respect to the handle assembly. The distal portion has a centerline and is selectively articulatable relative to the proximal portion of the shaft. The instrument includes an end effector mounted on the working end of the elongate shaft. The end effector is selectively rotatable about the distal portion of the shaft.