High pressure ball valve and packing

摘要

A ball valve for ultra-high pressure wherein the inner annular surface(s) of the valve seat(s) has an sealing face in sealing engagement with the flow control element, support surfaces adjacent the sealing face in contact with the flow control element, and vent grooves between adjacent support surfaces and the sealing face. A method to utilize the ball valve involves rotating the control element and maintaining a pressure of 275.8 MPa (40,000 psi) or more for at least 1 hour without leaking before opening or after closing the valve.

主权项

1. A method comprising:
locating a flow control assembly in a fluid flow bore disposed through a valve body, the fluid flow bore having an inlet end and an outlet end, the flow control assembly comprising a flow control element disposed between inlet and outlet valve seats and having an outer surface for sealing contact with an inner annular surface of the inlet and outlet valve seats; biasing the inlet valve seat against the flow control element with a Belleville spring; extending a valve stem from an outer end, with respect to the flow control element, through a packing bore disposed radially around the valve stem in the valve body to an inner end, with respect to the flow control element, of the valve stem to rotationally engage the inner end of the valve stem with a recess disposed in the flow control element; rotating the valve stem to rotate the flow control element between open and closed positions; applying a first pressurized fluid to the outlet end of the fluid flow bore to form a first fluid seal between a sealing face on a portion of the inner annular surface of the inlet valve seat in physical contact with the outer surface of the fluid flow control element; physically contacting the outer surface of the flow control element with a first plurality of support surfaces located on the inner annular surface adjacent the sealing face of the inlet valve seat; separating adjacent ones of the first plurality of support surfaces with a like plurality of vent grooves on the inner annular surface of the inlet valve seat between adjacent ones of the first plurality of support surfaces; and separating the first plurality of support surfaces from the sealing face of the inlet valve seat with an annular vent groove on the inner annular surface of the inlet valve seat between the respective sealing face and the support surfaces.