Valve assemblies for high-temperature wells

Abstract

A valve assembly suitable for use in a high temperature well, such as a geothermal well. The valve assembly comprises a tubular housing having ports to allow fluid communication between a fluid passageway in the valve assembly and the outside of the valve assembly, an outer sleeve longitudinally slidable in the tubular housing, and an inner sleeve longitudinally slidable in the outer sleeve. The outer and inner sleeves are slidable to various positions to prevent, allow or restrict flow through the ports. The valve assembly may include sealing assemblies that can withstand high temperatures, frangible plugs in the ports that can be sheared to open the ports, and/or a coupling member for coupling the inner and outer sleeve while the ports are being opened. The valve assembly may have ports configured in a manner that allows for sequential opening of the ports.

Dependencies are inferred from the claim text.