Local position indicator for subsea isolation valve having no external position indication

A subsea hydraulically operated valve assembly for isolation in a tubular string, comprising:

• a valve hydraulically operated through at least one control line between an open and a closed position without a visible indication of position;
• a position indicating assembly operably connected to said at least one control line responsive to a variable volume of hydraulic fluid moving between said control line and said position indicating assembly to visually indicate valve position subsea related to said moving volume.

An indicating method for a subsea hydraulically operated isolation valve having no external indication of its position, comprising:

• connecting a volumetric fluid displacement sensitive position indicator to a control line, said control line used to operate said valve;
• providing a visible indication subsea responsive to displaced hydraulic fluid volume, said displaced volume proportional to movement of said valve between an open and a closed position.

A valve assembly for subsea use, comprising:

• a hydraulically operated flapper valve further comprising a flapper valve housing with a passage therethrough selectively closed by a flapper in said passage;
• a surrounding outer housing for said flapper valve housing, said outer housing comprising flanged ends for connection to a marine riser to said passage;
• at least one opening in said outer housing for sealingly connecting at least one control line for hydraulic operation of said flapper valve through said flapper valve housing.