Patent ID: 9388663
Filing Date: 2016-07-12
CPC Classification: E21B

Claim Text:
1. A downhole circulating valve comprising: a generally tubular outer housing having an axially extending internal passageway including an internal seat having a spherical segment and at least one generally radially extending opening formed through the housing intersecting the spherical segment of the internal seat; and a valve element rotatably disposed within the internal passageway, the valve element having an axially extending internal bore and a head portion disposed at least partially within the internal seat, the head portion including at least one metal seal element extending generally radially from an outer surface of the head portion, the valve element having a first position relative to the housing wherein the at least one seal element is not aligned with the at least one opening allowing fluid communication between the at least one opening and the internal passageway and a second position relative to the housing wherein the at least one seal element is aligned with the at least one opening and wherein the at least one seal element comprises a pair of concentric seal rings each having a circular cross section and forms a metal-to-metal seal with the internal seat preventing fluid communication between the at least one opening and both the internal passageway and the axially extending internal bore.