Importance

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Abstract

A downhole, inline well safety shutoff valve has a spring-loaded, normally closed flapper shutoff valve element that may be opened by a downwardly driven movement of an operator tube coaxially and slidably disposed within the tubing string bore. The operator tube is vertically driven by a rod structure disposed in an offset passageway in the safety valve housing and operated by fluid control pressure transmitted thereto from the surface. To substantially preclude undesirable communication in the passageway between pressurized production fluid and pressurized rod control fluid, the rod structure is slidably carried within a specially designed seal structure including a cylindrical sleeve coaxially received in the offset passageway, and a sealing ring captively retained between the top end of the sleeve and an annular ledge formed in the passageway. The sealing ring functions to create a dynamic seal around the rod side surface and a static seal between the ring and the interior passageway surface. Upwardly and downwardly facing annular seating surfaces are formed on the lower end of the sleeve. In response to upward movement of the rod relative to the sleeve, an adapter secured to the reduced diameter rod portion engages and forms a static fluid seal with the downwardly facing seating surface. In response to downward movement of the rod relative to the sleeve, the rod undercut engages and forms a static fluid seal with the upwardly facing seating surface.

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First Claim